CN107071405B

CN107071405B - A kind of method for video coding and device

Info

Publication number: CN107071405B
Application number: CN201610956784.4A
Authority: CN
Inventors: 沈强; 陆金刚; 洪文先; 方伟
Original assignee: Zhejiang Dahua Technology Co Ltd
Current assignee: Zhejiang Dahua Technology Co Ltd
Priority date: 2016-10-27
Filing date: 2016-10-27
Publication date: 2019-09-17
Anticipated expiration: 2036-10-27
Also published as: CN107071405A

Abstract

The embodiment of the invention discloses a kind of method for video coding and devices, to solve the problems, such as that video coding efficiency is low in the prior art.The described method includes: determining the first brightness histogram of picture frame to be encoded；Determine the second brightness histogram of each reference frame saved in the first brightness histogram and reference frame lists difference and；Select corresponding minimum first difference of the long term reference frame saved in difference reference frame lists with described in and and corresponding minimum second difference of short-term reference frame and；The first threshold of preservation is compared with minimum first difference and is compared with second threshold with minimum second difference, coding mode and reference coding frame is determined, picture frame is encoded.Due in embodiments of the present invention in the coding mode and reference coding frame for determining described image frame, need to only calculate the second brightness histogram of each reference frame in the brightness histogram and reference frame lists of picture frame to be encoded difference and.Calculation amount is small, to improve the speed of coding.

Description

A kind of method for video coding and device

Technical field

The present invention relates to technical field of video coding, in particular to a kind of method for video coding and device.

Background technique

With the continuous progress of science and technology, video technique using more and more extensive, such as online video conferencing, online government affairs, The business such as online school, all videos in these business require to be transmitted, and the data volume of transmission is bigger, simple with expanding Large memories capacity, it is unpractical for increasing the transmission mode of communication trunk, and can effectively be dropped using data compression technique Low amount of transmitting data, this just needs to encode the picture frame in video.

In the prior art, it when being encoded to each picture frame in video, needs current image to be encoded Frame is divided at least two piecemeals, and the picture frame of piecemeal reference is calculated for each piecemeal, and is being directed to picture frame to be encoded When determining the picture frame of each piecemeal reference, calculation amount is larger, if the quantity of piecemeal is relatively more, calculation amount will be bigger, thus The serious efficiency for affecting Video coding.

Summary of the invention

The present invention provides a kind of method for video coding and device, to solve in the prior art for each figure in video It is computationally intensive when determining reference coding frame as frame, the problem of influencing video coding efficiency.

In order to achieve the above objectives, the embodiment of the invention discloses a kind of method for video coding, this method comprises:

According to the brightness value of pixel each in picture frame to be encoded, the first brightness histogram of described image frame is determined Figure；

For the second brightness histogram of each reference frame saved in reference frame lists, the first brightness histogram is determined Figure and second brightness histogram difference and；

For the long term reference frame saved in the reference frame lists, according to determining each long term reference frame corresponding One difference and, using first difference and in minimum value as minimum first difference with；For being protected in the reference frame lists The short-term reference frame deposited, according to determining corresponding second difference of each short-term reference frame and, by second difference and in Minimum value as minimum second difference and；

By the corresponding second threshold of short-term reference frame of the corresponding first threshold of the long term reference frame of preservation and preservation, with length Corresponding minimum first difference of phase reference frame minimum second difference corresponding with short-term reference frame is compared, and determines the figure As the coding mode and reference coding frame of frame, described image frame is carried out according to the reference coding frame using the coding mode Coding.

Further, the difference of the determination first brightness histogram and second brightness histogram and include:

For each brightness section, same brightness region in first brightness histogram and second brightness histogram is determined Between pixel quantity absolute value of the difference；

By the sum of the absolute value of each brightness section, it is determined as first brightness histogram and the second brightness histogram The difference of figure and.

Further, it is determined that the process of the corresponding first threshold of the long term reference frame includes:

Resolution ratio, the first coefficient and the third threshold value for long term reference frame setting for obtaining the video, by institute It states resolution ratio and the product of the third threshold value and is determined as the corresponding first threshold of the long term reference frame；Or

According to encoded first picture frame adjacent with described image frame of preservation and adjacent with the first image frame The brightness histogram of the second encoded picture frame determine the first image frame and the second figure for each brightness section As frame brightness histogram in same brightness section pixel quantity absolute value of the difference, by the absolute value of each brightness section Sum be determined as the first image frame and the second picture frame brightness histogram third difference and, by the third difference and It is determined as the corresponding first threshold of the long term reference frame with the product of the third coefficient of the long term reference frame of preservation；Or

Resolution ratio, the first coefficient and the third threshold value for long term reference frame setting for obtaining the video, by institute It states resolution ratio and the product of the third threshold value and is determined as corresponding first threshold value to be selected of the long term reference frame；According to preservation Encoded first picture frame adjacent with described image frame and encoded second image adjacent with the first image frame The brightness histogram of frame, for each brightness section, in the brightness histogram for determining the first image frame and the second picture frame The sum of the absolute value of each brightness section is determined as described first by the pixel quantity absolute value of the difference of same brightness section The third difference of the brightness histogram of picture frame and the second picture frame and, by the third difference and with the long term reference frame of preservation The product of third coefficient be determined as corresponding second threshold value to be selected of the long term reference frame；By the described first threshold value to be selected and Minimum value in two threshold values to be selected is determined as the corresponding first threshold of the long term reference frame.

Further, it is determined that the process of the corresponding second threshold of the short-term reference frame includes:

Resolution ratio, the second coefficient and the 4th threshold value for short-term reference frame setting for obtaining the video, by institute It states resolution ratio and is determined as the short-term reference frame corresponding with the product of the 4th threshold value described in the Shang Zaiyu of second coefficient Two threshold values；Or

According to encoded first picture frame adjacent with described image frame of preservation and adjacent with the first image frame The brightness histogram of the second encoded picture frame determine the first image frame and the second figure for each brightness section As frame brightness histogram in same brightness section pixel quantity absolute value of the difference, by the absolute value of each brightness section Sum be determined as the first image frame and the second picture frame brightness histogram third difference and；By the third difference and It is determined as the corresponding second threshold of the short-term reference frame with the product of the 4th coefficient of the short-term reference frame of preservation；Or

Resolution ratio, the second coefficient and the 4th threshold value for short-term reference frame setting for obtaining the video, by institute It states resolution ratio and is determined as the short-term reference frame corresponding with the product of the 4th threshold value described in the Shang Zaiyu of second coefficient Three threshold values to be selected；According to encoded first picture frame adjacent with described image frame of preservation and with the first image frame phase The brightness histogram of adjacent the second encoded picture frame determines the first image frame and second for each brightness section The pixel quantity absolute value of the difference of same brightness section in the brightness histogram of picture frame, this by each brightness section are absolute The sum of value be determined as the brightness histogram of the first image frame and the second picture frame third difference and, by the third difference It is determined as corresponding 4th threshold value to be selected of the short-term reference frame with the product of the 4th coefficient of the short-term reference frame of preservation；It will Minimum value in third threshold value to be selected and the 4th threshold value to be selected is determined as corresponding second threshold of the short-term reference coding frame Value.

Further, the corresponding first threshold of the long term reference frame by preservation and the short-term reference frame of preservation are corresponding Second threshold, minimum first difference corresponding with long term reference frame and corresponding minimum second difference of short-term reference frame are compared Compared with determining the coding mode of described image frame and reference coding frame include:

If corresponding minimum first difference of the long term reference frame is greater than the first threshold, and the short-term reference frame Corresponding minimum second difference is greater than the second threshold, determines that the coding mode of described image frame is intraframe coding, the figure As frame is without reference to any picture frame in the reference frame lists；

If corresponding minimum first difference of the long term reference frame is not more than the first threshold, and the short term reference Corresponding minimum second difference of frame is greater than the second threshold, determines that the coding mode of described image frame is to encode with reference to previous frame, Described image frame refers to minimum first difference and corresponding long term reference frame；

If corresponding minimum second difference of the short-term reference frame is not more than the second threshold, described image frame is determined Coding mode be with reference to previous frame encode, described image frame refer to minimum second difference and corresponding short-term reference frame.

Further, the method also includes:

If it is determined that the coding mode of described image frame is intraframe coding, described image frame is without reference to the reference frame lists In any picture frame, the method further includes: the reference frame lists are emptied, using described image frame as long-term ginseng Frame is examined to be added in the reference frame lists；

If it is determined that the coding mode of described image frame is to encode with reference to previous frame, described image frame refers to described minimum first Difference and corresponding long term reference frame, the method further includes: by all short-term reference frames in the reference frame lists It deletes, is added to described image frame as short-term reference frame in the reference frame lists；

If it is determined that the coding mode of described image frame is to encode with reference to previous frame, described image frame refers to described minimum second Difference and corresponding short-term reference frame, the method further includes: it will be with the longest ginseng in described image frame time interval The short-term reference frame examined in frame list removes, and is added to described image frame as short-term reference frame in the reference frame lists.

Further, it is described by with the short-term reference frame in the longest reference frame lists in described image frame time interval Before removal, the method also includes:

Judgement it is described with the short-term reference frame in the longest reference frame lists in described image frame time interval whether be Minimum second difference and corresponding short-term reference frame, if it is not, carrying out subsequent step.

Further, the short-term reference frame with the longest reference frame lists in described image frame time interval is When minimum second difference and corresponding short-term reference frame, the method also includes:

By in addition to minimum second difference and corresponding short-term reference frame with described image frame time interval longest Reference frame lists in short-term reference frame remove.

The embodiment of the invention discloses a kind of video coding apparatus, described device includes:

First determining module determines described image for the brightness value according to pixel each in picture frame to be encoded First brightness histogram of frame；

Second determining module, for the second brightness histogram for each reference frame saved in reference frame lists, really The difference of fixed first brightness histogram and second brightness histogram and；

Third determining module, for being directed to the long term reference frame saved in the reference frame lists, according to each of determining Corresponding first difference of long term reference frame and, using first difference and in minimum value as minimum first difference with；For The short-term reference frame saved in the reference frame lists, according to determining corresponding second difference of each short-term reference frame and general Second difference and in minimum value as minimum second difference and；

The short-term reference frame of coding module, the corresponding first threshold of long term reference frame and preservation for that will save is corresponding Second threshold, minimum first difference corresponding with long term reference frame and minimum second difference corresponding with short-term reference frame are compared Compared with the coding mode and reference coding frame of described image frame being determined, using the coding mode according to the reference coding frame pair Described image frame is encoded.

Further, second determining module is specifically used for being directed to each brightness section, determines that first brightness is straight The pixel quantity absolute value of the difference of same brightness section in side's figure and second brightness histogram；By being somebody's turn to do for each brightness section The sum of absolute value, be determined as first brightness histogram and second brightness histogram difference and.

Further, described device further include:

First threshold determining module, for obtaining the resolution ratio of the video, the first coefficient and for the long term reference The resolution ratio and the product of the third threshold value are determined as the long term reference frame corresponding the by the third threshold value of frame setting One threshold value；Or according to encoded first picture frame adjacent with described image frame of preservation and adjacent with the first image frame The brightness histogram of the second encoded picture frame determine the first image frame and the second figure for each brightness section As frame brightness histogram in same brightness section pixel quantity absolute value of the difference, by the absolute value of each brightness section Sum be determined as the first image frame and the second picture frame brightness histogram third difference and, by the third difference and It is determined as the corresponding first threshold of the long term reference frame with the product of the third coefficient of the long term reference frame of preservation；Or obtain institute State the resolution ratio of video, the first coefficient and the third threshold value for long term reference frame setting, by the resolution ratio with it is described The product of third threshold value is determined as corresponding first threshold value to be selected of the long term reference frame；According to preservation and described image frame phase The brightness histogram of adjacent the first encoded picture frame and encoded second picture frame adjacent with the first image frame, For each brightness section, the picture of same brightness section in the brightness histogram of the first image frame and the second picture frame is determined The sum of the absolute value of each brightness section is determined as the first image frame and the second image by vegetarian refreshments quantity absolute value of the difference The third difference of the brightness histogram of frame and, by the third difference and product with the third coefficient of the long term reference frame of preservation It is determined as corresponding second threshold value to be selected of the long term reference frame；By in the described first threshold value to be selected and the second threshold value to be selected most Small value is determined as the corresponding first threshold of the long term reference frame.

Further, described device further include:

Second threshold determining module, for obtaining the resolution ratio of the video, the second coefficient and for the short term reference The product of 4th threshold value described in the Shang Zaiyu of the resolution ratio and second coefficient is determined as institute by the 4th threshold value of frame setting State the corresponding second threshold of short-term reference frame；Or according to encoded first picture frame adjacent with described image frame of preservation and The brightness histogram of encoded second picture frame adjacent with the first image frame determines institute for each brightness section The pixel quantity absolute value of the difference for stating same brightness section in the brightness histogram of the first picture frame and the second picture frame, will be every The third that the sum of the absolute value of a brightness section is determined as the brightness histogram of the first image frame and the second picture frame is poor Value and；It is determined as the short-term reference frame pair by the third difference and with the product of the 4th coefficient of the short-term reference frame of preservation The second threshold answered；Or obtain resolution ratio, the second coefficient and the 4th threshold for short-term reference frame setting of the video The product of 4th threshold value described in the Shang Zaiyu of the resolution ratio and second coefficient is determined as the short-term reference frame pair by value The third answered threshold value to be selected；According to encoded first picture frame adjacent with described image frame of preservation and with first figure As the brightness histogram of adjacent the second encoded picture frame of frame determines the first image frame for each brightness section With the pixel quantity absolute value of the difference of same brightness section in the brightness histogram of the second picture frame, by each brightness section The sum of the absolute value be determined as the brightness histogram of the first image frame and the second picture frame third difference and, by described the Three differences and to be determined as the short-term reference frame with the product of the 4th coefficient of the short-term reference frame of preservation corresponding 4th to be selected Threshold value；It is corresponding that minimum value in third threshold value to be selected and the 4th threshold value to be selected is determined as the short-term reference coding frame Second threshold.

Further, the coding module, if it is big to be specifically used for corresponding minimum first difference of the long term reference frame In the first threshold, and corresponding minimum second difference of the short-term reference frame is greater than the second threshold, determines the figure As frame coding mode be intraframe coding, described image frame is without reference to any picture frame in the reference frame lists；If institute Corresponding minimum first difference of long term reference frame is stated no more than the first threshold, and the short-term reference frame corresponding minimum the Two differences are greater than the second threshold, determine that the coding mode of described image frame is to encode with reference to previous frame, the reference of described image frame Minimum first difference and corresponding long term reference frame；If corresponding minimum second difference of the short-term reference frame is not more than The second threshold determines that the coding mode of described image frame is to encode with reference to previous frame, and described image frame is with reference to described minimum the Two differences and corresponding short-term reference frame.

Further, described device further include:

First removing module, for if it is determined that the coding mode of described image frame is intraframe coding, described image frame to be not With reference to any picture frame in the reference frame lists, the reference frame lists are emptied, using described image frame as long-term ginseng Frame is examined to be added in the reference frame lists；

Second removing module, for if it is determined that the coding mode of described image frame is with reference to previous frame coding, described image Frame refers to minimum first difference and corresponding long term reference frame, and all short-term reference frames in the reference frame lists are deleted It removes, is added to described image frame as short-term reference frame in the reference frame lists；

Third removing module, for if it is determined that the coding mode of described image frame is with reference to previous frame coding, described image Frame refers to minimum second difference and corresponding short-term reference frame, will be with the longest reference in described image frame time interval Short-term reference frame in frame list removes, and is added to described image frame as short-term reference frame in the reference frame lists.

Further, described device further include:

Judgment module, for by with the short-term reference frame in the longest reference frame lists in described image frame time interval Before removal, judgement it is described with the short-term reference frame in the longest reference frame lists in described image frame time interval whether be Minimum second difference and corresponding short-term reference frame.

Further, described device further include:

4th removing module, the result for judgment module be when being, will be except minimum second difference and corresponding short Being removed with the short-term reference frame in the longest reference frame lists in described image frame time interval except phase reference frame.

The embodiment of the invention discloses a kind of method for video coding and devices, which comprises according to figure to be encoded As the brightness value of pixel each in frame, the first brightness histogram of described image frame is determined；For being saved in reference frame lists Each reference frame the second brightness histogram, determine the difference of first brightness histogram and second brightness histogram With；It is corresponding first poor according to determining each long term reference frame for the long term reference frame saved in the reference frame lists Value and, using first difference and in minimum value as minimum first difference with；For what is saved in the reference frame lists Short-term reference frame, according to determining corresponding second difference of each short-term reference frame and, by second difference and in minimum Value as minimum second difference and；The short-term reference frame of the corresponding first threshold of the long term reference frame of preservation and preservation is corresponding Second threshold, minimum first difference corresponding with long term reference frame and minimum second difference corresponding with short-term reference frame are compared Compared with the coding mode and reference coding frame of described image frame being determined, using the coding mode according to the reference coding frame pair Described image frame is encoded.Due in embodiments of the present invention according to the first brightness histogram of picture frame to be encoded and ginseng Examine the difference and corresponding with the long term reference frame of preservation of the second brightness histogram of each reference frame saved in frame list One threshold value and the corresponding second threshold of the short-term reference frame of preservation are compared, the coding mode and volume of determining described image frame Code reference frame, need to only calculate it is primary, and calculate be picture frame to be encoded brightness histogram and reference frame lists in protect The difference of second brightness histogram of each reference frame deposited and, calculation amount is small, to improve the efficiency of Video coding.

Detailed description of the invention

In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is only this Some embodiments of invention for those of ordinary skill in the art without creative efforts, can be with It obtains other drawings based on these drawings.

Figure 1A is a kind of video coding process schematic diagram that the embodiment of the present invention 1 provides；

Figure 1B is a kind of first brightness histogram of picture frame provided in an embodiment of the present invention；

Fig. 2A is a kind of reference frame lists provided in an embodiment of the present invention；

Fig. 2 B is a kind of video coding process schematic diagram that the embodiment of the present invention 4 provides；

Fig. 3 is a kind of video coding apparatus structure chart that the embodiment of the present invention 1 provides；

Fig. 4 is a kind of video coding apparatus structure chart that the embodiment of the present invention 4 provides.

Specific embodiment

When in order to reduce Video coding, the calculation amount of the reference coding frame of each picture frame is determined, improve Video coding effect Rate, the embodiment of the invention provides a kind of method for video coding and devices.

Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other Embodiment shall fall within the protection scope of the present invention.

Embodiment 1:

Figure 1A be a kind of video coding process schematic diagram provided in an embodiment of the present invention, the process the following steps are included:

S101: according to the brightness value of pixel each in picture frame to be encoded, the first brightness of described image frame is determined Histogram.

The embodiment of the invention provides a kind of method for video coding, this method can be applied to electronic equipment, the electronics Equipment can be PC, can also be monitoring device, and electronic equipment can obtain picture frame to be encoded from video source, can also be from Picture frame to be encoded is obtained in the video locally saved.

There is the pixel of identical quantity in each picture frame of same video, pixel is more, and the resolution ratio of picture is got over The height, image the fine and smooth true to nature.The brightness value of pixel is different, constitutes the picture of different color brightness.Because in picture frame Brightness range can be divided at least two brightness regions generally within a brightness range by the brightness value of pixel Between, each brightness section counts each brightness according to the brightness value of pixel each in picture frame as a brightness degree Pixel quantity under grade.Using horizontal axis as brightness section, the longitudinal axis is that pixel quantity constructs coordinate system, thus according to picture frame In all corresponding brightness value of pixel, statistics is located at the pixel quantity of each brightness section, and then determines brightness histogram Figure.

For example, the brightness value of pixel is located in 0~255 range in a picture frame, then 0~255 range can be drawn It is divided into N number of brightness section, wherein the value of N is not more than 256, and it is integer that N, which is greater than 1, N,.If taking N is 32, by 0~255 Be divided into 0~7,8~15,16~23,24~31,32~39 ..., 248~255, this 32 brightness sections are denoted as bright respectively Section i is spent, i is the integer between 1 to 32.It counts in described image frame, brightness value is located at the pixel of each brightness section Quantity will be denoted as Hi positioned at the pixel quantity of brightness section i, i.e. H0 indicates the brightness value of described image frame between 0~7 Pixel quantity, H1 indicate described image frame brightness value be 8~15 between pixel quantity, and so on.

As shown in Figure 1B, be the first brightness histogram of picture frame, the longitudinal axis be brightness section 0~7,8~15,16~23, 24~31,32~39 ..., 248~255, horizontal axis is pixel quantity, and wherein brightness value is located at the pixel of brightness section 0~7 Point is 9, and the pixel that brightness value is located at brightness section 8~15 is 6, and brightness value is located at the pixel of brightness section 16~23 It is 10, the pixel that brightness value is located at brightness section 248~255 is 2 ... ..., and brightness value is located at other brightness sections Pixel quantity and brightness value are located at the pixel quantity statistical method of brightness section 0~7,8~15,16~23,248~255 Equally, pixel quantity can be any integer value.

In embodiments of the present invention when determining the brightness histogram of each picture frame, all drawn using identical brightness section The mode of dividing, thereby may be ensured that the accuracy of subsequent comparison.

S102: for the second brightness histogram of each reference frame saved in reference frame lists, determine that described first is bright Spend histogram and second brightness histogram difference and.

At least one in store reference frame in reference frame lists, can be true for each reference frame in reference frame lists Its fixed corresponding each brightness histogram, and brightness histogram can be stored in histogram storage unit.Using certain When the brightness histogram of a reference frame, it need to only be directly acquired from the histogram storage unit of electronic equipment, no longer need to determine, into One step improves the efficiency of Video coding.Second brightness histogram of in store each reference frame in histogram storage unit, In include in second brightness histogram brightness section and the first brightness histogram in include brightness section it is identical.

For each second brightness histogram, in the difference for determining first brightness histogram and second brightness histogram Value and when, for each brightness section, determine same brightness region in first brightness histogram and second brightness histogram Between pixel quantity absolute value of the difference；By the sum of the absolute value of each brightness section, it is determined as the first brightness histogram Figure and second brightness histogram difference and.

S103: for the long term reference frame saved in the reference frame lists, according to determining each long term reference frame pair The first difference for answering and, using first difference and in minimum value as minimum first difference with；For the reference frame list The short-term reference frame saved in table, according to determining corresponding second difference of each short-term reference frame and, by second difference Minimum value in as minimum second difference and.

Reference frame is specifically preserved in reference frame lists, and is directed to each mark for having the reference frame with reference to frame recording Information and each reference frame are long term reference frame or short-term reference frame.Wherein long reference frame can be in reference frame lists Keep longer time.Reference frame lists as shown in Figure 2 A, it can be seen that include two long term references in the reference frame lists Frame and three short-term reference frames.

Multiple reference frames are generally had in one reference frame lists, and long term reference can be existed simultaneously in most cases Frame and short-term reference frame.It is calculated in S102 each in the first brightness histogram and the reference frame lists of described image frame The difference of corresponding second brightness histogram of reference frame and, and to have each reference frame be to join for a long time to record in reference frame lists Examine frame or short-term reference frame, therefore can be for the long term reference frame saved in the reference frame lists, according to determining every Corresponding first difference of a long term reference frame and, using first difference and in minimum value as minimum first difference and, institute As soon as state the first difference and may be, that using this first difference and as minimum first difference and, if at least two, Just using first difference and in minimum value as minimum first difference with.It is short-term for being saved in the reference frame lists Reference frame, according to determining corresponding second difference of each short-term reference frame and, by second difference and in minimum value make For minimum second difference and, as soon as second difference and may be that is using this second difference and as minimum first Difference and, if at least two, just using second difference and in minimum value as minimum the second difference with.

S104: by corresponding second threshold of the short-term reference frame of the corresponding first threshold of the long term reference frame of preservation and preservation Value, minimum first difference corresponding with long term reference frame and minimum second difference corresponding with short-term reference frame are compared, really The coding mode and reference coding frame for determining described image frame, using the coding mode according to the reference coding frame to the figure As frame is encoded.

The corresponding first threshold of in store long term reference frame and the corresponding second threshold of short-term reference frame in the electronic device, The first threshold and second threshold are directly proportional to the resolution ratio of video, and the resolution ratio of video is bigger, and value is bigger.Described first Threshold value and second threshold, which can be user and be manually entered into electronic equipment, save, and electronic equipment calculating is also possible to It is automatically saved after out.

By the corresponding first threshold of the long term reference frame of preservation minimum first difference corresponding with long term reference frame and progress Compare, and by the corresponding second threshold of the short-term reference frame of preservation minimum second difference corresponding with short-term reference frame and compares Compared with determining the coding mode and reference coding frame of described image frame, and using the coding mode according to the reference coding frame Described image frame is encoded.

According to comparison result, when determining reference frame of the described image frame in coding, it is confirmed that a reference coding frame, The reference coding frame can be the long term reference frame saved in reference frame lists, be also possible to save in reference frame lists short-term Reference frame, described image frame can also be without reference to any reference frames in reference frame lists in coding.

Due in embodiments of the present invention according in the first brightness histogram of picture frame to be encoded and reference frame lists The difference and first threshold corresponding with the long term reference frame of preservation of second brightness histogram of each reference frame saved and guarantor The corresponding second threshold of the short-term reference frame deposited is compared, the coding mode and reference coding frame of determining described image frame, It need to only calculate primary, and what is calculated is each ginseng for saving in the brightness histogram and reference frame lists of picture frame to be encoded Examine the second brightness histogram of frame difference and, calculation amount is small, to improve the efficiency of Video coding.

Embodiment 2:

When determining first threshold and second threshold, it can be determined in the method in above-described embodiment, other can also be used Method determines, in embodiments of the present invention, determines that the process of the corresponding first threshold of the long term reference frame includes:

According to encoded first picture frame adjacent with described image frame of preservation and adjacent with the first image frame The brightness histogram of the second encoded picture frame determine the first image frame and the second figure for each brightness section As frame brightness histogram in same brightness section pixel quantity absolute value of the difference, by the absolute value of each brightness section Sum be determined as the first image frame and the second picture frame brightness histogram third difference and；By the third difference and It is determined as the corresponding first threshold of the long term reference frame with the product of the third coefficient of the long term reference frame of preservation；Or

In embodiments of the present invention, when determining the corresponding first threshold of the long term reference frame, it can be and obtain the view The resolution ratio of frequency, the first coefficient and the third threshold value for long term reference frame setting, by the resolution ratio and described first The product of third threshold value described in the Shang Zaiyu of coefficient is determined as the corresponding first threshold of the long term reference frame.The third threshold value It is the preset threshold unrelated with the resolution of video image, which, which can be used for adjusting, judges the image to be encoded The sensitivity of the difference of long term reference frame in frame and reference frame lists.When determining first threshold, specifically can according to Lower formula calculates:

THresh_long=(image_width*image_height/2^N)*thresh_long_pre

Wherein, Thresh_long is the first threshold；Image_width*image_height is point of the video Resolution；2^NFor the first coefficient；Thresh_long_pre is third threshold value.The Nth power that first coefficient is 2 preferably can Think 26 powers, as 64.

Histogram storage unit in electronic equipment preserves encoded first picture frame adjacent with described image frame And the brightness histogram of encoded second picture frame adjacent with the first image frame.Because of first picture frame and second Picture frame is all encoded picture frame, when encoding to each picture frame, can all determine the brightness histogram of the picture frame Figure can be by first picture frame and the therefore after the brightness histogram of first picture frame and the second picture frame has been determined The brightness histogram of two picture frames is added in histogram storage unit.

Third coefficient is preserved also directed to the long term reference frame in reference frame lists in electronic equipment, the third coefficient Value range can be 1~100.

When determining the corresponding first threshold of the long term reference frame, can be according to being saved in histogram storage unit Encoded first picture frame adjacent with described image frame and encoded second image adjacent with the first image frame The brightness histogram of frame first determines that same brightness section is corresponding in the brightness histogram of the first image frame and the second picture frame Pixel number third difference, the third difference is taken absolute value, then by the sum of the absolute value of the third difference with The product of the third coefficient of the long term reference frame of preservation is determined as the corresponding first threshold of the long term reference frame；By the third The product of 4th coefficient of the short-term reference frame of the absolute value and preservation of difference is determined as the short-term reference frame corresponding second Threshold value.

When determining the corresponding first threshold of the long term reference frame, it is also possible to obtain the resolution ratio of the video, first Coefficient and the third threshold value set for the long term reference frame, the product of the resolution ratio and the third threshold value is determined as Corresponding first threshold value to be selected of the long term reference frame；According to encoded first image adjacent with described image frame of preservation The brightness histogram of frame and encoded second picture frame adjacent with the first image frame, for each brightness section, really Determine the pixel quantity absolute value of the difference of same brightness section in the brightness histogram of the first image frame and the second picture frame, The sum of the absolute value of each brightness section is determined as the of the brightness histogram of the first image frame and the second picture frame Three differences and, be determined as the long term reference by the third difference and with the product of the third coefficient of the long term reference frame of preservation Corresponding second threshold value to be selected of frame；Minimum value in described first threshold value to be selected and the second threshold value to be selected is determined as described long-term The corresponding first threshold of reference frame.In this way when first threshold to be compared with minimum first difference, determining institute can be made Coding mode and the reference coding frame for stating picture frame are more accurate, improve the accuracy of coding.

The process for determining the corresponding second threshold of the short-term reference frame includes:

In embodiments of the present invention, it when determining the corresponding second threshold of the short-term reference frame, can be described in acquisition The resolution ratio of video, the second coefficient and the 4th threshold value for short-term reference frame setting, by the resolution ratio and described the The product of 4th threshold value described in the Shang Zaiyu of two coefficients is determined as the corresponding second threshold of the short-term reference frame.4th threshold Value is the preset threshold unrelated with the resolution ratio of video image, and the 4th threshold value, which can be used for adjusting, judges the figure to be encoded As the sensitivity of the difference of the short-term reference frame in frame and reference frame lists.It, specifically can basis when determining second threshold Following formula calculates:

THresh_short=(image_width*image_height/2^N)*thresh_short_pre

Wherein, Thresh_short is the second threshold；Image_width*image_height is the video Resolution ratio；2^NFor the second coefficient；Thresh_short_pre is the 4th threshold value.The Nth power that second coefficient is 2, preferably, Can be 26 powers, as 64.

The 4th coefficient is preserved also directed to the short-term reference frame in reference frame lists in electronic equipment, the 4th coefficient Value range can be 1~100.

When determining the corresponding second threshold of the short-term reference frame, can be according to being saved in histogram storage unit Encoded first picture frame adjacent with described image frame and encoded second image adjacent with the first image frame The brightness histogram of frame first determines that same brightness section is corresponding in the brightness histogram of the first image frame and the second picture frame Pixel number third difference, the third difference is taken absolute value, then by the sum of the absolute value of the third difference with The product of 4th coefficient of the short-term reference frame of preservation is determined as the corresponding second threshold of the short-term reference frame；By the third The product of 4th coefficient of the short-term reference frame of the absolute value and preservation of difference is determined as the short-term reference frame corresponding second Threshold value.When calculating, the third coefficient and the 4th coefficient can be identical value, be also possible to different values.

When determining the corresponding first threshold of the long term reference frame, it is also possible to obtain the resolution ratio of the video, second Coefficient and the 4th threshold value for short-term reference frame setting, will be described in the Shang Zaiyu of the resolution ratio and second coefficient The product of 4th threshold value is determined as the corresponding third of short-term reference frame threshold value to be selected；According to preservation and described image frame phase The brightness histogram of adjacent the first encoded picture frame and encoded second picture frame adjacent with the first image frame, For each brightness section, the picture of same brightness section in the brightness histogram of the first image frame and the second picture frame is determined The sum of the absolute value of each brightness section is determined as the first image frame and the second image by vegetarian refreshments quantity absolute value of the difference The third difference of the brightness histogram of frame and, by the third difference and product with the 4th coefficient of the short-term reference frame of preservation It is determined as corresponding 4th threshold value to be selected of the short-term reference frame；By in third threshold value to be selected and the 4th threshold value to be selected most Small value is determined as the corresponding second threshold of the short-term reference coding frame.It is carried out in this way by second threshold and minimum second difference When comparing, the coding mode of determining described image frame and reference coding frame can be made more accurate, improve the accurate of coding Property.

When determining the first threshold and the second threshold, identical method can be taken to determine, can also be used Different methods determines.

Embodiment 3:

On the basis of the various embodiments described above, according to the comparison result and second threshold of first threshold and minimum first difference With the comparison result of minimum second difference, the coding mode and reference coding frame of described image frame can be determined, of the invention real It applies in example, the corresponding second threshold of short-term reference frame of the corresponding first threshold of the long term reference frame by preservation and preservation, Minimum first difference corresponding with long term reference frame and corresponding minimum second difference of short-term reference frame are compared, described in determination The coding mode and reference coding frame of picture frame include:

In the present invention is implemented, the corresponding first threshold of long term reference frame is preserved in electronic equipment and preserves short-term ginseng Examine the corresponding second threshold of frame, electronic equipment by the first threshold of preservation minimum first difference corresponding with long term reference frame and into Row compares, and by the second threshold of preservation minimum second difference corresponding with short-term reference frame and is compared, and ties according to comparing Fruit determines the coding mode and reference coding frame of described image frame.

If corresponding minimum first difference of long term reference frame is greater than the first threshold, and the short-term reference frame is corresponding The second difference of minimum be greater than the second threshold, then show that all reference frames in described image frame and reference frame lists have Larger difference, it is determined that need for the picture frame to be encoded to I frame, corresponding type of coding is intraframe coding.Because by image Frame is encoded to I frame without reference to frame, and all reference frames in described image frame and reference frame lists have larger difference, therefore should Intraframe coding method is without reference to frame.The process that picture frame is encoded to I frame is wherein belonged to by existing skill by intraframe coding method Art, in embodiments of the present invention to the process without repeating.

If corresponding minimum first difference of the long term reference frame is not more than the first threshold, and the short term reference Corresponding minimum second difference of frame is greater than the second threshold, then shows described image frame and minimum first difference and corresponding length The difference of phase reference frame is smaller, it is determined that needs for the picture frame to be encoded to P frame, corresponding type of coding is to compile with reference to previous frame Code.P frame needs to refer to coded picture frame in reference frame lists when encoding, described image frame and minimum first difference and right The difference for the long term reference frame answered is smaller, it is therefore desirable to which the reference coding frame for determining picture frame in embodiments of the present invention should The reference coding frame of picture frame is determined as minimum first difference and corresponding long term reference frame.Wherein by reference to previous frame coding staff The process that picture frame is encoded to P frame is belonged to the prior art by formula, in embodiments of the present invention to the process without repeating.

If corresponding minimum second difference of the short-term reference frame is not more than the second threshold, show described image The difference of frame and minimal difference and corresponding short-term reference frame is minimum, it is determined that needs the picture frame being encoded to P frame, correspond to Type of coding be with reference to previous frame encode.Corresponding minimum first difference of long term reference frame can be greater than first threshold at this time Value, might be less that the first threshold, can also be equal to the first threshold.P frame needs to refer to reference frame lists when encoding In the difference of coded picture frame, described image frame and minimal difference and corresponding short-term reference frame it is minimum, it is therefore desirable to Determine the reference coding frame of picture frame, it is poor that the reference coding frame of the picture frame is determined as minimum second in embodiments of the present invention Value and corresponding short-term reference frame.Wherein the process that picture frame is encoded to P frame is belonged to by reference to preceding frame coding mode existing Technology, in embodiments of the present invention to the process without repeating.

The coding mode of described image frame can be intraframe coding, be also possible to encode with reference to previous frame.

Reference frame of the described image frame in coding can be the long term reference frame saved in reference frame lists, be also possible to The short-term reference frame saved in reference frame lists, described image frame can also be without reference to any in reference frame lists in coding Picture frame.Reference frame of the described image frame in coding is at most a reference frame in reference frame lists.

Embodiment 4:

The reference frame lists can also be carried out more in the coding mode and reference coding frame for determining described image frame Newly, so that the subsequent picture frame for needing to encode is more accurate when determining coding mode and reference coding frame, in above-mentioned each reality On the basis of applying example, in embodiments of the present invention, the method also includes:

If it is determined that the coding mode of described image frame is to encode with reference to previous frame, described image frame refers to described minimum second Difference and corresponding short-term reference frame, the method further includes: by the reference frame lists farthest from described image frame In short-term reference frame remove, be added to described image frame as short-term reference frame in the reference frame lists.

In embodiments of the present invention, after the coding mode and reference coding frame that described image frame has been determined, also to reference Reference frame in frame list is updated, specifically, if it is determined that the coding mode of described image frame is intraframe coding, the figure As frame is without reference to any picture frame in the reference frame lists, the method further includes: the reference frame lists are clear Sky is added to described image frame as long term reference frame in the reference frame lists, and by the reference frame labeled as long-term Reference frame.

If it is determined that the coding mode of described image frame is to encode with reference to previous frame, described image frame refers to described minimum first Difference and corresponding long term reference frame, the method further includes: by all short-term reference frames in the reference frame lists It deletes, is added to described image frame as short-term reference frame in the reference frame lists.

Embodiment 5:

It is described in embodiments of the present invention in order to guarantee the accuracy of accuracy when coding and the reference frame lists of update By before removing with the short-term reference frame in the longest reference frame lists in described image frame time interval, the method is also wrapped It includes:

If not being the minimum with the short-term reference frame in the longest reference frame lists in described image frame time interval Second difference and corresponding short-term reference frame, so that it may will in the longest reference frame lists in described image frame time interval Short-term reference frame remove.

The short-term reference frame with the longest reference frame lists in described image frame time interval is the minimum When the second difference and corresponding short-term reference frame, the method also includes:

If reference frame lists are updated before described image frame coding, because with the longest institute in described image frame time interval Stating short-term reference frame is minimum second difference and corresponding short-term reference frame, is needed to refer to when described image frame is in coding Second difference of minimum and corresponding short-term reference frame then cannot remove it from reference frame lists, at this time will be except described in most Except small second difference and corresponding short-term reference frame with it is short in the longest reference frame lists in described image frame time interval Phase reference frame removes.Ensure the accuracy of coding.

If updating reference frame lists after described image frame coding, because described minimum the second of the reference of described image frame Difference and corresponding short-term reference frame and described image frame difference are minimum, adjacent uncoded first picture frame of described image frame Minimum second difference and corresponding short-term reference frame of the reference of described image frame are probably referred in coding, so if It is minimum second difference and right with the short-term reference frame in the longest reference frame lists in described image frame time interval The short-term reference frame answered, then cannot by with the short-term reference frame in the longest reference frame lists in described image frame time interval Remove, but by addition to minimum second difference and corresponding short-term reference frame with described image frame time interval longest Reference frame lists in short-term reference frame remove.Ensure the accuracy of the reference frame lists of update.

, can be using first judging whether first threshold is greater than minimum first difference when being compared, whether second threshold Method greater than minimum second difference is compared, specifically can be as shown in Figure 2:

Fig. 2 B be a kind of video coding process schematic diagram provided in an embodiment of the present invention, the process the following steps are included:

S105: by corresponding second threshold of the short-term reference frame of the corresponding first threshold of the long term reference frame of preservation and preservation Value, minimum first difference corresponding with long term reference frame and minimum second difference corresponding with short-term reference frame are compared.

S201: judge whether that corresponding minimum first difference of the long term reference frame is greater than the first threshold, and short Corresponding minimum second difference of phase reference frame is greater than the second threshold, if so, S202 is carried out, if it is not, then carrying out S204.

S202: the coding mode for determining described image frame is intraframe coding, and described image frame is without reference to the reference frame list Any picture frame in table.

S203: the reference frame lists are emptied, and are added to the reference frame for described image frame as long term reference frame In list.

S204: judging whether corresponding minimum second difference of the short-term reference frame is greater than the second threshold, if so, S205 is carried out, if it is not, then carrying out S207.

S205: the coding mode for determining described image frame is to encode with reference to previous frame, and described image frame is with reference to described minimum the One difference and corresponding long term reference frame.

S206: by all short term reference frame deletions in the reference frame lists, using described image frame as short term reference Frame is added in the reference frame lists.

S207: the coding mode for determining described image frame is to encode with reference to previous frame, and described image frame is with reference to described minimum the Two differences and corresponding short-term reference frame.

S208: judgement is described to be with the short-term reference frame in the longest reference frame lists in described image frame time interval No is minimum second difference and corresponding short-term reference frame, if so, S209 is carried out, if it is not, carrying out S2010.

S209: by addition to minimum second difference and corresponding short-term reference frame with described image frame time interval Short-term reference frame in longest reference frame lists removes.

S2010: it will be removed with the short-term reference frame in the longest reference frame lists in described image frame time interval.

Fig. 3 is a kind of video coding apparatus structure chart that the embodiment of the present invention 1 provides, and described device includes:

First determining module 31 determines the figure for the brightness value according to pixel each in picture frame to be encoded As the first brightness histogram of frame；

Second determining module 32, for being directed to the second brightness histogram of each reference frame saved in reference frame lists, Determine first brightness histogram and second brightness histogram difference and；

Third determining module 33, for for the long term reference frame saved in the reference frame lists, according to determining every Corresponding first difference of a long term reference frame and, using first difference and in minimum value as minimum first difference with；Needle To the short-term reference frame saved in the reference frame lists, according to determining corresponding second difference of each short-term reference frame and, Using second difference and in minimum value as minimum second difference with；

The short-term reference frame of coding module 34, the corresponding first threshold of long term reference frame and preservation for that will save is corresponding Second threshold, minimum first difference corresponding with long term reference frame and minimum second difference corresponding with short-term reference frame carry out Compare, the coding mode and reference coding frame of described image frame is determined, using the coding mode according to the reference coding frame Described image frame is encoded.

Second determining module 32, be specifically used for be directed to each brightness section, determine first brightness histogram and The pixel quantity absolute value of the difference of same brightness section in second brightness histogram；By the absolute value of each brightness section Sum, be determined as first brightness histogram and second brightness histogram difference and.

Described device further include:

The coding module 34, if being specifically used for corresponding minimum first difference of the long term reference frame is greater than described the One threshold value, and corresponding minimum second difference of the short-term reference frame is greater than the second threshold, determines the volume of described image frame Code mode is intraframe coding, and described image frame is without reference to any picture frame in the reference frame lists；If the long-term ginseng Corresponding minimum first difference of frame is examined no more than the first threshold, and corresponding minimum second difference of the short-term reference frame is big In the second threshold, determine that the coding mode of described image frame is to encode with reference to previous frame, described image frame refers to the minimum First difference and corresponding long term reference frame；If corresponding minimum second difference of the short-term reference frame is not more than described second Threshold value determines that the coding mode of described image frame is to encode with reference to previous frame, described image frame with reference to minimum second difference and Corresponding short-term reference frame.

Fig. 4 is a kind of video coding apparatus structure chart that the embodiment of the present invention 4 provides, on the basis of Fig. 1, described device Further include:

First removing module 41, for if it is determined that the coding mode of described image frame is intraframe coding, described image frame Without reference to any picture frame in the reference frame lists, the reference frame lists are emptied, using described image frame as long-term Reference frame is added in the reference frame lists；

Second removing module 42, for if it is determined that the coding mode of described image frame is with reference to previous frame coding, the figure Picture frame refers to minimum first difference and corresponding long term reference frame, by all short-term reference frames in the reference frame lists It deletes, is added to described image frame as short-term reference frame in the reference frame lists；

Third removing module 43, for if it is determined that the coding mode of described image frame is with reference to previous frame coding, the figure Picture frame refers to minimum second difference and corresponding short-term reference frame, will be with the longest ginseng in described image frame time interval The short-term reference frame examined in frame list removes, and is added to described image frame as short-term reference frame in the reference frame lists.

Described device further include:

Judgment module 44, for by with the short term reference in the longest reference frame lists in described image frame time interval Before frame removes, whether the judgement short-term reference frame with the longest reference frame lists in described image frame time interval For minimum second difference and corresponding short-term reference frame.

Described device further include:

4th removing module 45, the result for judgment module be when being, will be except minimum second difference and corresponding Being removed with the short-term reference frame in the longest reference frame lists in described image frame time interval except short-term reference frame.

For systems/devices embodiment, since it is substantially similar to the method embodiment, so the comparison of description is simple Single, the relevent part can refer to the partial explaination of embodiments of method.

It should be noted that, in this document, relational terms such as first and second and the like are used merely to a reality Body or an operation are distinguished with another entity or another operation, without necessarily requiring or implying these entities Or there are any actual relationship or orders between operation.

It should be understood by those skilled in the art that, embodiments herein can provide as method, system or computer program Product.Therefore, complete hardware embodiment, complete software embodiment or reality combining software and hardware aspects can be used in the application Apply the form of example.Moreover, it wherein includes the computer of computer usable program code that the application, which can be used in one or more, The computer program implemented in usable storage medium (including but not limited to magnetic disk storage, CD-ROM, optical memory etc.) produces The form of product.

The application is referring to method, the process of equipment (system) and computer program product according to the embodiment of the present application Figure and/or block diagram describe.It should be understood that every one stream in flowchart and/or the block diagram can be realized by computer program instructions The combination of process and/or box in journey and/or box and flowchart and/or the block diagram.It can provide these computer programs Instruct the processor of general purpose computer, special purpose computer, Embedded Processor or other programmable data processing devices to produce A raw machine, so that being generated by the instruction that computer or the processor of other programmable data processing devices execute for real The device for the function of being specified in present one or more flows of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions, which may also be stored in, is able to guide computer or other programmable data processing devices with spy Determine in the computer-readable memory that mode works, so that it includes referring to that instruction stored in the computer readable memory, which generates, Enable the manufacture of device, the command device realize in one box of one or more flows of the flowchart and/or block diagram or The function of being specified in multiple boxes.

These computer program instructions also can be loaded onto a computer or other programmable data processing device, so that counting Series of operation steps are executed on calculation machine or other programmable devices to generate computer implemented processing, thus in computer or The instruction executed on other programmable devices is provided for realizing in one or more flows of the flowchart and/or block diagram one The step of function of being specified in a box or multiple boxes.

Although the preferred embodiment of the application has been described, it is created once a person skilled in the art knows basic Property concept, then additional changes and modifications can be made to these embodiments.So it includes excellent that the following claims are intended to be interpreted as It selects embodiment and falls into all change and modification of the application range.

Obviously, those skilled in the art can carry out various modification and variations without departing from the essence of the application to the application Mind and range.In this way, if these modifications and variations of the application belong to the range of the claim of this application and its equivalent technologies Within, then the application is also intended to include these modifications and variations.

Claims

1. a kind of method for video coding, which is characterized in that the described method includes:

According to the brightness value of pixel each in picture frame to be encoded, the first brightness histogram of described image frame is determined；

For the second brightness histogram of each reference frame saved in reference frame lists, determine first brightness histogram and The difference of second brightness histogram and；

It is corresponding first poor according to determining each long term reference frame for the long term reference frame saved in the reference frame lists Value and, using first difference and in minimum value as minimum first difference with；For what is saved in the reference frame lists Short-term reference frame, according to determining corresponding second difference of each short-term reference frame and, by second difference and in minimum Value as minimum second difference and；

By the corresponding second threshold of short-term reference frame of the corresponding first threshold of the long term reference frame of preservation and preservation, with long-term ginseng It examines corresponding minimum first difference of frame minimum second difference corresponding with short-term reference frame to be compared, determines described image frame Coding mode and reference coding frame, described image frame is compiled according to the reference coding frame using the coding mode Code.

2. the method according to claim 1, wherein the determination first brightness histogram and this is second bright It spends the difference of histogram and includes:

For each brightness section, same brightness section in first brightness histogram and second brightness histogram is determined Pixel quantity absolute value of the difference；

By the sum of the absolute value of each brightness section, it is determined as first brightness histogram and second brightness histogram Difference and.

3. the method according to claim 1, wherein determining the mistake of the corresponding first threshold of the long term reference frame Journey includes:

Resolution ratio, the first coefficient and the third threshold value for long term reference frame setting of the video are obtained, it will be described point Resolution and the product of the third threshold value are determined as the corresponding first threshold of the long term reference frame；Or

According to encoded first picture frame adjacent with described image frame of preservation and it is adjacent with the first image frame The brightness histogram of second picture frame of coding determines the first image frame and the second picture frame for each brightness section Brightness histogram in same brightness section pixel quantity absolute value of the difference, by the sum of the absolute value of each brightness section Be determined as the brightness histogram of the first image frame and the second picture frame third difference and, by the third difference and with guarantor The product of the third coefficient for the long term reference frame deposited is determined as the corresponding first threshold of the long term reference frame；Or

Resolution ratio, the first coefficient and the third threshold value for long term reference frame setting of the video are obtained, it will be described point Resolution and the product of the third threshold value are determined as corresponding first threshold value to be selected of the long term reference frame；According to preservation and institute State adjacent the first encoded picture frame of picture frame and encoded second picture frame adjacent with the first image frame Brightness histogram determines same in the brightness histogram of the first image frame and the second picture frame for each brightness section The sum of the absolute value of each brightness section is determined as the first image by the pixel quantity absolute value of the difference of brightness section The third difference of the brightness histogram of frame and the second picture frame and, by the third difference and with the long term reference frame of preservation the The product of three coefficients is determined as corresponding second threshold value to be selected of the long term reference frame；By the described first threshold value to be selected and second to The minimum value in threshold value is selected to be determined as the corresponding first threshold of the long term reference frame.

4. method according to claim 1 or 3, which is characterized in that determine the corresponding second threshold of the short-term reference frame Process include:

Resolution ratio, the second coefficient and the 4th threshold value for short-term reference frame setting of the video are obtained, it will be described point Resolution and the product of the 4th threshold value described in the Shang Zaiyu of second coefficient are determined as corresponding second threshold of the short-term reference frame Value；Or

According to encoded first picture frame adjacent with described image frame of preservation and it is adjacent with the first image frame The brightness histogram of second picture frame of coding determines the first image frame and the second picture frame for each brightness section Brightness histogram in same brightness section pixel quantity absolute value of the difference, by the sum of the absolute value of each brightness section Be determined as the brightness histogram of the first image frame and the second picture frame third difference and；By the third difference and with guarantor The product of 4th coefficient of the short-term reference frame deposited is determined as the corresponding second threshold of the short-term reference frame；Or

Resolution ratio, the second coefficient and the 4th threshold value for short-term reference frame setting of the video are obtained, it will be described point Resolution and the product of the 4th threshold value described in the Shang Zaiyu of second coefficient are determined as the corresponding third of the short-term reference frame and wait for Select threshold value；According to encoded first picture frame adjacent with described image frame of preservation and adjacent with the first image frame The brightness histogram of the second encoded picture frame determines the first image frame and the second image for each brightness section The pixel quantity absolute value of the difference of same brightness section in the brightness histogram of frame, by the absolute value of each brightness section With the third difference of the brightness histogram that is determined as the first image frame and the second picture frame and, by the third difference and with The product of 4th coefficient of the short-term reference frame of preservation is determined as corresponding 4th threshold value to be selected of the short-term reference frame；It will be described Minimum value in third threshold value to be selected and the 4th threshold value to be selected is determined as the corresponding second threshold of the short-term reference frame.

5. the method according to claim 1, wherein the corresponding first threshold of the long term reference frame by preservation Second threshold corresponding with the short-term reference frame of preservation, minimum first difference corresponding with long term reference frame and short-term reference frame pair The second difference of minimum answered is compared, and determines the coding mode of described image frame and reference coding frame includes:

If corresponding minimum first difference of the long term reference frame is greater than the first threshold, and the short-term reference frame is corresponding The second difference of minimum be greater than the second threshold, determine described image frame coding mode be intraframe coding, described image frame Without reference to any picture frame in the reference frame lists；

If corresponding minimum first difference of the long term reference frame is not more than the first threshold, and the short-term reference frame pair The second difference of minimum answered is greater than the second threshold, determines that the coding mode of described image frame is to encode with reference to previous frame, described Picture frame refers to minimum first difference and corresponding long term reference frame；

If corresponding minimum second difference of the short-term reference frame is not more than the second threshold, the volume of described image frame is determined Code mode is to encode with reference to previous frame, and described image frame refers to minimum second difference and corresponding short-term reference frame.

6. according to the method described in claim 5, it is characterized in that, the method also includes:

If it is determined that the coding mode of described image frame is intraframe coding, described image frame is without reference in the reference frame lists Any picture frame, the method further includes: the reference frame lists are emptied, using described image frame as long term reference frame It is added in the reference frame lists；

If it is determined that the coding mode of described image frame is to encode with reference to previous frame, described image frame refers to minimum first difference With corresponding long term reference frame, the method further includes: by all short term reference frame deletions in the reference frame lists, It is added to described image frame as short-term reference frame in the reference frame lists；

If it is determined that the coding mode of described image frame is to encode with reference to previous frame, described image frame refers to minimum second difference With corresponding short-term reference frame, the method further includes: will be with the longest reference frame in described image frame time interval Short-term reference frame in list removes, and is added to described image frame as short-term reference frame in the reference frame lists.

7. according to the method described in claim 6, it is characterized in that, described will be longest described with described image frame time interval Before short-term reference frame in reference frame lists removes, the method also includes:

Whether the judgement short-term reference frame with the longest reference frame lists in described image frame time interval is described Minimum second difference and corresponding short-term reference frame, if it is not, carrying out subsequent step.

8. the method according to the description of claim 7 is characterized in that the described and longest ginseng in described image frame time interval When to examine short-term reference frame in frame list be minimum second difference and corresponding short-term reference frame, the method also includes:

By in addition to minimum second difference and corresponding short-term reference frame with described image frame time interval longest ginseng The short-term reference frame examined in frame list removes.

9. a kind of video coding apparatus, which is characterized in that described device includes:

First determining module determines described image frame for the brightness value according to pixel each in picture frame to be encoded First brightness histogram；

Second determining module determines institute for the second brightness histogram for each reference frame saved in reference frame lists State the first brightness histogram and second brightness histogram difference and；

Third determining module, for being directed to the long term reference frame saved in the reference frame lists, according to each of determining long-term Corresponding first difference of reference frame and, using first difference and in minimum value as minimum first difference with；For described The short-term reference frame saved in reference frame lists, according to determining corresponding second difference of each short-term reference frame and, will be described Second difference and in minimum value as minimum second difference and；

Coding module, the short-term reference frame corresponding second of the corresponding first threshold of long term reference frame and preservation for that will save Threshold value, minimum first difference corresponding with long term reference frame and minimum second difference corresponding with short-term reference frame are compared, The coding mode and reference coding frame for determining described image frame, using the coding mode according to the reference coding frame to described Picture frame is encoded.

10. device according to claim 9, which is characterized in that second determining module is specifically used for for each bright Section is spent, determines the pixel quantity difference of same brightness section in first brightness histogram and second brightness histogram Absolute value；By the sum of the absolute value of each brightness section, it is determined as first brightness histogram and the second brightness histogram The difference of figure and.

11. device according to claim 9, which is characterized in that described device further include:

First threshold determining module, for obtaining the resolution ratio of the video, the first coefficient and being set for the long term reference frame The resolution ratio and the product of the third threshold value are determined as corresponding first threshold of the long term reference frame by fixed third threshold value Value；Or according to encoded first picture frame adjacent with described image frame of preservation and it is adjacent with the first image frame The brightness histogram of second picture frame of coding determines the first image frame and the second picture frame for each brightness section Brightness histogram in same brightness section pixel quantity absolute value of the difference, by the sum of the absolute value of each brightness section Be determined as the brightness histogram of the first image frame and the second picture frame third difference and, by the third difference and with guarantor The product of the third coefficient for the long term reference frame deposited is determined as the corresponding first threshold of the long term reference frame；Or obtain the view The resolution ratio of frequency, the first coefficient and the third threshold value for long term reference frame setting, by the resolution ratio and the third The product of threshold value is determined as corresponding first threshold value to be selected of the long term reference frame；According to the adjacent with described image frame of preservation The brightness histogram of encoded the first picture frame and encoded second picture frame adjacent with the first image frame, for Each brightness section determines the pixel of same brightness section in the brightness histogram of the first image frame and the second picture frame The sum of the absolute value of each brightness section is determined as the first image frame and the second picture frame by quantity absolute value of the difference The third difference of brightness histogram and, determined by the third difference and with the product of the third coefficient of the long term reference frame of preservation For corresponding second threshold value to be selected of the long term reference frame；By the minimum value in the described first threshold value to be selected and the second threshold value to be selected It is determined as the corresponding first threshold of the long term reference frame.

12. the device according to claim 9 or 11, which is characterized in that described device further include:

Second threshold determining module, for obtaining the resolution ratio of the video, the second coefficient and being set for the short-term reference frame The product of 4th threshold value described in Shang Zaiyu of the resolution ratio with second coefficient is determined as described short by the 4th fixed threshold value The corresponding second threshold of phase reference frame；Or according to encoded first picture frame adjacent with described image frame of preservation and with institute The brightness histogram for stating adjacent the second encoded picture frame of the first picture frame determines described for each brightness section The pixel quantity absolute value of the difference of same brightness section in the brightness histogram of one picture frame and the second picture frame, will be each bright Spend section the absolute value sum be determined as the first image frame and the second picture frame brightness histogram third difference with； It is corresponding to be determined as the short-term reference frame by the third difference and with the product of the 4th coefficient of the short-term reference frame of preservation Second threshold；Or resolution ratio, the second coefficient and the 4th threshold value for short-term reference frame setting of the video are obtained, it will It is corresponding that the resolution ratio with the product of the 4th threshold value described in the Shang Zaiyu of second coefficient is determined as the short-term reference frame Third threshold value to be selected；According to encoded first picture frame adjacent with described image frame of preservation and with the first image frame The brightness histogram of adjacent the second encoded picture frame determines the first image frame and for each brightness section The pixel quantity absolute value of the difference of same brightness section in the brightness histogram of two picture frames, this by each brightness section are exhausted To the sum of value be determined as the brightness histogram of the first image frame and the second picture frame third difference and, the third is poor Value and it is determined as corresponding 4th threshold value to be selected of the short-term reference frame with the product of the 4th coefficient of the short-term reference frame of preservation； Minimum value in third threshold value to be selected and the 4th threshold value to be selected is determined as the corresponding second threshold of the short-term reference frame.

13. device according to claim 9, which is characterized in that the coding module, if being specifically used for the long-term ginseng Corresponding minimum first difference of frame is examined greater than the first threshold, and corresponding minimum second difference of the short-term reference frame is greater than The second threshold determines that the coding mode of described image frame is intraframe coding, and described image frame is without reference to the reference frame list Any picture frame in table；If corresponding minimum first difference of the long term reference frame is not more than the first threshold, and institute Corresponding minimum second difference of short-term reference frame is stated greater than the second threshold, determines the coding mode of described image frame for reference Previous frame coding, described image frame refer to minimum first difference and corresponding long term reference frame；If the short-term reference frame Corresponding minimum second difference is not more than the second threshold, determines that the coding mode of described image frame is to encode with reference to previous frame, Described image frame refers to minimum second difference and corresponding short-term reference frame.

14. device according to claim 13, which is characterized in that described device further include:

First removing module, for if it is determined that described image frame coding mode be intraframe coding, described image frame without reference to Any picture frame in the reference frame lists, the reference frame lists are emptied, using described image frame as long term reference frame It is added in the reference frame lists；

Second removing module, for if it is determined that the coding mode of described image frame is to encode with reference to previous frame, described image frame to be joined Minimum first difference and corresponding long term reference frame are examined, by all short term reference frame deletions in the reference frame lists, It is added to described image frame as short-term reference frame in the reference frame lists；

Third removing module, for if it is determined that the coding mode of described image frame is to encode with reference to previous frame, described image frame to be joined Minimum second difference and corresponding short-term reference frame are examined, it will be with the longest reference frame list in described image frame time interval Short-term reference frame in table removes, and is added to described image frame as short-term reference frame in the reference frame lists.

15. device according to claim 14, which is characterized in that described device further include:

Judgment module, for will be removed with the short-term reference frame in the longest reference frame lists in described image frame time interval Before, whether the judgement short-term reference frame with the longest reference frame lists in described image frame time interval is described Minimum second difference and corresponding short-term reference frame.

16. device according to claim 15, which is characterized in that described device further include:

4th removing module, the result for judgment module are that when being, will remove minimum second difference and corresponding short-term ginseng Examine removing except frame with the short-term reference frame in the longest reference frame lists in described image frame time interval.