CN101453556B - Method and apparatus for deblurring images by pixel-based processing - Google Patents

Abstract

A method for removing image blur, comprising: performing motion detection on two pixels respectively located at corresponding positions of two continuous images of a video to generate a detection result; and adjusting the brightness of the two pixels according to the detection result, wherein when the detection result indicates that the two pixels belong to the dynamic image, one of the two pixels is brightened, and the other pixel is darkened.

Description

Method and apparatus for deblurring images by pixel-based processing

technical field

The present invention relates to a solution to motion image blur of a hold type display device, in particular to a method and device for eliminating image blur through pixel-based processing.

Background technique

For a hold type display device, such as an active matrix liquid crystal display (AMLCD), motion image blur is a widely discussed issue. Causes of moving image blur include: slow liquid crystal response time, capacitance changes in pixels, and so-called "sample and hold artifacts."

According to known technologies, the former two can be solved by using methods such as voltage overdrive. However, the latter is relatively difficult to deal with because it is a combination of the sampling characteristics of the active matrix liquid crystal display and the smooth motion tracking characteristics of the user's visual system, so it is still widely present in the liquid crystal display on the market. . The solutions for sampling and holding artifacts in the prior art are not perfect. For example, in a known solution, the sense of visual continuity is broken by intermittently replacing part of the image data with the data of a completely black image, in order to destroy the effect of sampling and maintaining artifacts. For another example, in another known solution, the visual sense of continuity is broken by intermittently turning off the backlight power of the liquid crystal display, so as to break the effect of sampling and holding artifacts. However said known solutions all have the problem of darkening of the image.

In addition, the solutions provided by the known technologies often require rather complex control mechanisms and consume relatively high R&D/manufacturing costs, which are not conducive to introducing products on the market.

Contents of the invention

Therefore, one object of the present invention is to provide a method and device for eliminating image blur, so as to solve the above problems.

Another object of the present invention is to provide a method and device for eliminating image blur, so as to solve the motion image blur problem of a hold type display device.

Another object of the present invention is to provide a method and an apparatus for eliminating image blurring to deal with sample and hold artifacts of an image displayed on a display device.

In a preferred embodiment of the present invention, a method for removing blurring of an image is provided. The method includes: performing motion detection on two pixels respectively located at corresponding positions of two consecutive images of a video to generate a detection result; and adjusting the brightness of the two pixels according to the detection result, wherein when the detection When the result indicates that the two pixels belong to a dynamic image, one of the two pixels is brightened, and the other pixel is dimmed.

While providing the above method, the present invention also correspondingly provides a device for eliminating image blur. The device includes a motion detector and an adjustment circuit, wherein the adjustment circuit is coupled to the motion detector. The motion detector is used for motion detection of two pixels located at corresponding positions of two consecutive images of a video to generate a detection result. The adjustment circuit is used to adjust the brightness of the two pixels according to the detection result, wherein when the detection result indicates that the two pixels belong to a dynamic image, one of the two pixels is brightened, and the other is brightened. Pixel dimmed.

Description of drawings

FIG. 1 is a schematic diagram of a device for eliminating image blur according to a first embodiment of the present invention.

FIG. 2 shows implementation details of the device shown in FIG. 1 in an embodiment, where this embodiment is a variation of the first embodiment.

FIG. 3 shows a schematic diagram of a conversion function that can be utilized by the adjustment circuit shown in FIG. 1 in a variation of the first embodiment.

Fig. 4 shows the implementation details of the device shown in Fig. 1 in another embodiment, where this embodiment is another variation of the first embodiment and also a variation of the embodiment shown in Fig. 2 .

Fig. 5 is a schematic diagram of a device for eliminating image blur provided according to a second embodiment of the present invention, wherein the second embodiment is another variation example of the first embodiment, also shown in Fig. 4 Variations of the embodiments are shown.

FIG. 6 is a schematic diagram of the dynamic adjustment and response time acceleration module shown in FIG. 5 .

Description of reference symbols

100, 200 A device for eliminating image blur 110,210 pixel comparison engine 120   Adjustment circuit 122 static image comparison table 124 Dynamic image comparison table 126   Gain adjustment unit 128 Multiplexer 130   Response time acceleration circuit 140 external memory 150 decision unit 200M   Dynamic adjustment and response time acceleration module C0, C1, C2 conversion function

Detailed ways

Please refer to FIG. 1. FIG. 1 is a schematic diagram of a device 100 for eliminating image blur provided according to a first embodiment of the present invention, wherein the device 100 of this embodiment can be set on a hold type display device (hold type display device), such as: active matrix liquid crystal display (AMLCD), and can be used to eliminate the blurring of the image of the sustaining display device, especially to eliminate the above-mentioned sampling and maintaining artifacts (sample and hold artifact) .

The device 100 includes a pixel-based motion detector; for the sake of brevity, it will be referred to as a motion detector hereinafter. In this embodiment, the motion detector is used to perform motion detection on two pixels at corresponding positions in two consecutive images of a video to generate a detection result. As shown in FIG. 1 , the motion detector of this embodiment is a pixel comparison engine (pixelcomparison engine) 110, which detects the difference between two pixels respectively located at corresponding positions (for example: the same position) in the two consecutive images. Whether the difference is greater than a threshold value (threshold value), to determine whether the detection result corresponds to a static image or a dynamic image. According to this embodiment, if the difference is greater than the threshold, the detection result corresponds to a dynamic image; otherwise, the detection result corresponds to a static image. In addition, as shown in FIG. 1 , the device 100 also includes an adjustment circuit 120, which can adjust the values of the two pixels at corresponding positions of the two consecutive images according to the comparison table corresponding to the detection results. brightness.

According to this embodiment, the detection result is represented by the state of the motion index (motion index, MI) MI shown in FIG. 1 . In this way, the movement index MI carrying the detection result can control the operation of the adjustment circuit 120 . When the detection result indicates that the two pixels belong to a dynamic image, the motion index MI is in a first state (for example: logic value 1); in this case, the adjusting circuit 120 will brighten one of the two pixels, The other pixel is dimmed to interrupt the motion tracking of the user's visual system to avoid blurry images. On the contrary, when the detection result indicates that the two pixels belong to the static image, the motion index MI is in a second state (for example: logic value 0); in this case, the adjustment circuit 120 will perform the same gamma on the two pixels Ma (GAMMA) conversion. In a variation of this embodiment, when the detection result indicates that the two pixels belong to a static image, the adjustment circuit 120 does not perform any adjustment on the two pixels.

Since the cause of sampling and maintaining artifacts is closely related to the visual sense of continuity, the above-mentioned brightness adjustment mechanism will destroy the visual sense of continuity, and when adjusting the brightness, it selectively performs a clear-cut for every two consecutively transmitted images Darkness adjustment, so the present invention can eliminate the above-mentioned sampling and holding artifacts, and the average brightness can maintain the proper brightness of the image, without causing the problem of darkening the image as in the known technology.

FIG. 2 shows implementation details of the device 100 shown in FIG. 1 in an embodiment, where this embodiment is a variation of the first embodiment. As shown in FIG. 2 , the device 100 further includes an external memory 140 for temporarily storing image data of the video. In this embodiment, the external memory 140 is a synchronous dynamic random access memory (Synchronous Dynamic Random Access Memory, SDRAM).

The previous data PRE_DATA and the current data CURR_DATA shown in FIG. 2 respectively represent pixel data of two consecutive images. For example: when the current data CURR_DATA represents the pixel data of the frame F(n), the previous data PRE_DATA represents the pixel data of the frame F(n-1). In addition, the adjusted current data CURR_DATA_ADJ represents the result of processing the current data CURR_DATA by the adjustment circuit 120 .

According to this embodiment, the adjustment circuit 120 includes a plurality of look-up tables (LUTs), so that the adjustment of the brightness of the video can be completed by looking up the tables. As shown in FIG. 2 , the multiple lookup tables include a static image lookup table 122 and at least one dynamic image lookup table 124 . When the detection result indicates that the two pixels belong to a static image, the adjustment circuit 120 adjusts the brightness of the two pixels by querying the static image comparison table 122; when the detection result indicates that the two pixels belong to a dynamic image, the adjustment circuit 120 The brightness of the two pixels is adjusted by querying the dynamic image comparison table 124 .

As shown in FIG. 2 , the adjustment circuit 120 further includes a multiplexer 128 . The multiplexer 128 of this embodiment is based on the detection result represented by the motion index MI, from the adjusted pixel data of the two pixels obtained by using the static image comparison table 122 and the two pixels obtained by using the dynamic image comparison table 124 Among the adjusted pixel data, one is selected as the output of the adjustment circuit 120 . In this way, through the selective operation of the multiplexer 128 , the adjustment circuit 120 of this embodiment can use the static image lookup table 122 or the dynamic image lookup table 124 to adjust the brightness of the two pixels.

In this embodiment, the content (that is, the value/data) in the comparison table represents a "conversion function". The still image lookup table 122 stores data representing a conversion function for adjusting the two pixels, for example: the still image lookup table 122 includes a lookup table value representing the function C0. In addition, the dynamic image lookup table 124 stores data representing two different conversion functions for adjusting the two pixels, for example: the dynamic image lookup table 124 includes a lookup table value representing function C1 and a lookup table representing function C2 value, where the function C2 is used to lighten the brightness of the image, and the function C1 is used to darken the brightness of the image.

FIG. 3 shows a schematic diagram of transfer functions available to the adjustment circuit 120 shown in FIG. 1 in a variation of the first embodiment. The curve shapes of the functions C0, C1, and C2 shown in this variation example are only one example of many possible variations, and are not intended to limit the scope of the present invention. For example: in another variation of the first embodiment, the shape of the curve of the function C0 is not a straight line.

According to another variation of the first embodiment, the two conversion functions provided by the dynamic image comparison table 124 are selected from a group of predetermined conversion functions. Especially in this modification example, the conversion function provided by the static image comparison table 122 and the conversion function provided by the dynamic image comparison table 124 are all gamma conversion functions, wherein each conversion function corresponds to a gamma value .

For example: when the detection result indicates that the two pixels belong to a static image, the adjustment circuit 120 uses the same conversion function corresponding to the same gamma value GAMMA0 as the adjustment mechanism in two consecutive images, wherein the gamma value GAMMA0 is between Between the two gamma values GAMMA1 and GAMMA2; thus, the adjustment circuit 120 uses the same gamma value GAMMA0 to preset (default) the pixels belonging to the static image in the frames F(n) and F(n+1) Gamma conversion.

On the other hand, when the detection result indicates that the two pixels belong to a dynamic image, the adjustment circuit 120 uses the conversion functions corresponding to different gamma values GAMMA1 and GAMMA2 as the adjustment mechanism in the two consecutive images; thus, the adjustment The circuit 120 can use the gamma value GAMMA2 to respectively brighten the pixels belonging to the dynamic image in the frame F(n), and use the gamma value GAMMA1 to respectively dim the pixels belonging to the dynamic image in the frame F(n+1).

Fig. 4 shows the implementation details of the device 100 shown in Fig. 1 in another embodiment, where this embodiment is another variation of the first embodiment and also a variation of the embodiment shown in Fig. 2 example. As shown in FIG. 4 , the adjustment circuit 120 further includes a gain adjustment unit 126 . The function provided by the gain adjustment unit 126 in the lower path of the adjustment circuit 120 is further described as follows.

In this embodiment, the two conversion functions provided by the dynamic image look-up table 124 are selected from a group of predetermined conversion functions, and each predetermined conversion function corresponds to a predetermined gain adjustment amount. The gain adjustment unit 126 of this embodiment adjusts the gain after looking up the table according to a predetermined gain adjustment amount G, so as to adjust the brightness of the video; =0, 1, ..., n, (n+1), ...) determine the appropriate gain adjustment amount G for use by the gain adjustment unit 126, so the gain adjustment amount G can also be written as the gain adjustment amount G _N . In this embodiment, the gain adjustments used in two consecutive frames, such as _Gn and Gn _+1, correspond to each other, so that the look-up table value of the function C2 and the gain adjustment _Gn are combined into a function ( _Gn *C2), And the look-up table value of the function C1 is combined with the gain adjustment amount Gn ₊₁ to form a function (Gn ₊₁ *C1).

The decision unit 150 of this embodiment will control the adjustment circuit 120 to select two predetermined conversion functions from the predetermined conversion functions according to the frame characteristics, so as to serve as the two pixels when the detection result indicates that the two pixels belong to a dynamic image. conversion function. In this embodiment, the aforementioned frame characteristic corresponds to the degree of movement of at least one object in the detected image. In practice, the moving degree can be the moving range of the object, the moving speed of the object, or the moving vector of the object.

As shown in Figure 4, in this embodiment, the device 100 also includes a response time acceleration circuit (Response Time Enhancement Circuit, RTE Circuit) 130, which is used to selectively perform overdrive (Overdrive, OD) processing, wherein the overdrive The data OD_DATA represents the pixel data output by the response time acceleration circuit 130 . Multiple components in the device 100 of this embodiment, such as the pixel comparison engine 110 , the adjustment circuit 120 , and the response time acceleration circuit 130 , are integrated into one chip. In practice, the comparison table is implemented by using an embedded memory (Embedded Memory) in the chip and a corresponding memory access control circuit.

The aforementioned moving index MI can control the adjustment circuit 120 and the response time acceleration circuit 130 at the same time. When the detection result indicates that the two pixels belong to a dynamic image, the motion index MI is in the first state (for example: logic value 1); Pixels are overdriven. On the contrary, when the detection result indicates that the two pixels belong to the static image, the motion index MI is in the second state (for example, logic value 0); in this case, the response time acceleration circuit 130 disables the overdrive process.

In addition, according to a variation of this embodiment, the conversion functions corresponding to red, green, and blue color channels (R/G/B color channel) are different, and the adjustment circuit 120 in this variation is based on Sets of transfer functions corresponding to the red, green, and blue color channels operate.

Please refer to Figure 5 and Figure 6. Fig. 5 is a schematic diagram of a device 200 for eliminating image blur provided according to a second embodiment of the present invention, and Fig. 6 is a dynamic adjustment and response time acceleration module (Dynamic Adjustment and Response) shown in Fig. 5 Schematic diagram of Time EnhancementModule, Dynamic Adjustment and RTE Module) 200M. The second embodiment is a modification example of the embodiment shown in FIG. 4 , and the differences are described as follows. In the second embodiment, the data path of the previous data PRE_DATA does not pass through the pixel comparison engine 210 , as shown in FIGS. 5 and 6 . According to this structure, the pixel comparison engine 210 compares the current data CURR_DATA with the next data NEXT_DATA. For example, the previous data PRE_DATA, the current data CURR_DATA, and the next data NEXT_DATA respectively correspond to frame data of frames F(n−1), F(n), and F(n+1). Since the current data CURR_DATA to be displayed by the display device coupled to the device 200 is processed by the device 200, the next data NEXT_DATA has already entered the device 200 for comparison, so this embodiment can adjust the current data according to the next data NEXT_DATA in real time. Data CURR_DATA.

Compared with the embodiment shown in FIG. 4, the device 200 can simultaneously compare the previous data PRE_DATA, the current data CURR_DATA, and the next data NEXT_DATA so as to dynamically determine whether to use the static image comparison table 122 or use the dynamic image comparison table. 124, and the adjusted current data CURR_DATA_ADJ is further processed by the response time acceleration circuit 130 immediately to generate overdrive data OD_DATA for real-time display by the display device.

One of the advantages of the present invention is that the method and apparatus provided by the present invention can eliminate image blur, especially eliminate sampling and hold artifacts, through pixel-based processing. Therefore, through the adjustment of the present invention, the image viewed by the user will not have the problem of brightness distortion or insufficient brightness.

The above descriptions are only preferred embodiments of the present invention, and all equivalent changes and modifications made according to the claims of the present invention shall fall within the scope of the present invention.

Claims (14)

1. one kind is used for the fuzzy method of removal of images, and it includes:

Two pixels of the opposite position of two consecutive images that lay respectively at a video are moved detect to produce a testing result; And

Adjust the brightness of these two pixels according to this testing result, wherein when this testing result points out that these two pixels belong to dynamic image, then the pixel in these two pixels is lightened, and another pixel is dimmed through inquiring about a dynamic image table of comparisons;

When this testing result points out that these two pixels belong to still image, adjust the brightness of these two pixels through inquiring about a still image table of comparisons.

2. the method for claim 1, wherein this dynamic image table of comparisons has the data of representing two transfer functions, and a transfer function in these two transfer functions is used for lightening the brightness of image, and another transfer function is used for dimming the brightness of image.

3. method as claimed in claim 2, wherein these two transfer functions are selected from the predetermined transfer function of a group.

4. method as claimed in claim 3, wherein said transfer function are the gamma conversion function, and each transfer function is corresponding to a gamma value.

5. the method for claim 1, wherein this still image table of comparisons has the data of representing a gamma conversion function.

6. the method for claim 1 also comprises:

According to this testing result, to the processing of overdriving of these two pixels.

7. one kind is used for the fuzzy device of removal of images, and it includes:

One moving detector is used for two pixels to the opposite position of two consecutive images laying respectively at a video to move and detect to produce a testing result; And

One adjustment circuit; Be coupled to this moving detector; Be used for brightness according to these two pixels of this testing result adjustment; Wherein this adjustment circuit comprises a dynamic image table of comparisons and a still image table of comparisons, and this adjustment circuit can be adjusted the brightness of these two pixels through inquiring about this still image table of comparisons;

Wherein when this testing result pointed out that these two pixels belong to dynamic image, then this adjustment circuit can lighten a pixel in these two pixels through inquiring about this dynamic image table of comparisons, and one other pixel is dimmed;

When this testing result pointed out that these two pixels belong to still image, then this adjustment circuit can be adjusted the brightness of these two pixels through inquiring about this still image table of comparisons.

8. device as claimed in claim 7, wherein this dynamic image table of comparisons has the data of representing two transfer functions, and a transfer function in these two transfer functions is used for lightening the brightness of image, and another transfer function is used for dimming the brightness of image.

9. device as claimed in claim 8, wherein these two transfer functions are selected from the predetermined transfer function of a group.

10. device as claimed in claim 9, wherein said transfer function are the gamma conversion function, and each transfer function is corresponding to a gamma value.

11. device as claimed in claim 7, wherein this still image table of comparisons has the data of representing a gamma conversion function.

12. device as claimed in claim 7, wherein this adjustment circuit also includes:

One multiplexer; Couple this moving detector, this dynamic image table of comparisons and this still image table of comparisons; Be used for according to this testing result; From these two adjusted pixel datas of pixel that utilize this still image table of comparisons gained with utilize in these two adjusted pixel datas of pixel of this dynamic image table of comparisons gained, select the output of one of which as this adjustment circuit.

13. device as claimed in claim 7 also comprises:

One decision unit is in order to determine a yield value; And

One gain adjusting unit is coupled to output and this decision unit of this dynamic image table of comparisons, in order to adjust the dateout of this dynamic image table of comparisons according to this yield value.

14. device as claimed in claim 7, wherein this moving detector and this adjustment are circuit integrated in a chip; This device also includes:

One external memory storage is coupled to this moving detector, is used for temporarily storing the view data of this video.

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