CN118921447A - Image display method and device - Google Patents

Abstract

An image display method and device are disclosed, relating to the technical field of multimedia. The image display method comprises the following steps: the video processing equipment adjusts the video time sequence adopted by the displayed images, and when the total display time length of each frame of images is the same and the difference between the time length of the blanking period and the time length of the effective period in the adjusted video time sequence is smaller than or equal to a threshold value, the time length of the blanking period and the time length of the effective period tend to be similar or identical, and the liquid crystal crosstalk rate caused by liquid crystal inversion is reduced. And compared with the problem that the duration of the backlight is shorter due to the fact that the duration of the blanking period and the duration of the effective period tend to be similar or identical, the duration of the blanking period is increased under the condition that the total display duration of each frame of image is the same, the duration of the backlight is increased by the video processing equipment, and the display brightness of the image and the display effect of the video to which the image belongs are improved.

Description

Image display method and device

Technical Field

The present application relates to the field of multimedia technology, and in particular to an image display method and device.

Background Art

Three-dimensional (3D) display technology can provide a display experience that is closer to the visual effect of the human eye. In order to enable viewers to obtain a stereoscopic display effect without wearing any auxiliary equipment, the display device refreshes the liquid crystal and backlight based on the directional backlight technology, and loads the left and right eye images in turn. In order to reduce the visual image overlap caused by liquid crystal crosstalk, the controller in the display device cooperates with the flipping of the liquid crystal to control the lighting or shutting down of the backlight unit. For example, the controller lights up the backlight unit during the blanking period and turns off the backlight unit during the active period. However, the blanking period is short, resulting in a shorter lighting time of the backlight unit, which reduces the display brightness of the image and deteriorates the display effect of the video. Therefore, how to improve the display effect of the video while reducing liquid crystal crosstalk has become a problem that needs to be solved urgently.

Summary of the invention

The present application provides an image display method and device, which solves the problem of reduced image display brightness and deteriorated video display effect caused by a short backlight lighting time.

In the first aspect, the present application provides an image display method. The method can be applied to a video processing device or a display device, or a display system including a physical device that executes the image display method, such as the physical device may include a chip or a chip system. Taking the video processing device executing the image display method as an example, the image display method includes: the video processing device obtains the video timing of the displayed first image, and updates the video timing according to the set first threshold value, and obtains the updated video timing. Among them, the video timing of the first image indicates: the first blanking period for lighting the backlight for the first image and the first valid period for turning off the backlight, and the sum of the duration of the first blanking period and the first valid period is the first duration; the updated video timing indicates: the second blanking period and the second valid period, the difference between the duration of the second blanking period and the second valid period is less than or equal to the first threshold, and the sum of the duration of the second blanking period and the second valid period is the first duration. And, the video processing device lights the backlight for the second image to be displayed in the second blanking period according to the updated video timing.

The video processing device adjusts the video timing used to display the image, and when the total display time of each frame of the image is the same and the difference between the blanking period and the effective period in the adjusted video timing is less than or equal to the threshold, the blanking period and the effective period are made close or consistent, thereby reducing the liquid crystal crosstalk rate caused by liquid crystal flipping. In addition, compared with the problem of a shorter backlighting time caused by a shorter blanking period, since the blanking period and the effective period are close or consistent, when the total display time of each frame of the image is the same, the blanking period is increased, and the time the video processing device turns on the backlight is increased, which is beneficial to improving the display brightness of the image and the display effect of the video to which the image belongs.

As a feasible example, the duration of the aforementioned second blanking period is consistent with the duration of the second valid period.

In an optional implementation, the video timing of the first image further indicates: a first pixel clock frequency for lighting the backlight for the first image; and the updated video timing further indicates: a second pixel clock frequency for lighting the backlight for the second image. The second pixel clock frequency is greater than the first pixel clock frequency.

In the present application, the video processing device updates the video timing so that in the updated video timing, while the number of pixels output each time remains unchanged, the pixel clock frequency (pixel clock, PCLK) increases, thereby increasing the number of pixels that the video processing device can output per unit time, which is beneficial to maintaining the screen refresh rate of the video timing before and after the update, and avoiding the problem of a reduced screen refresh rate of the video due to the unchanged pixel clock frequency in the video timing before and after the update.

In an optional implementation manner, the displayed first image and the second image to be displayed belong to a first stream (such as a video stream or a data stream), and the screen refresh rate corresponding to the first stream is a first value.

The video timing of the aforementioned first image includes: a first vertical blanking pixel number and a vertical effective pixel number used to display the first image; the first value, the first vertical blanking pixel number and the vertical effective pixel number are used to determine a first blanking period and a first effective period.

The updated video timing includes: a second vertical blanking pixel number and a vertical effective pixel number used to display the second image; the first value, the second vertical blanking pixel number and the vertical effective pixel number are used to determine a second blanking period and a second effective period.

The second vertical blanking pixel number is greater than the first vertical blanking pixel number, and the difference between the second vertical blanking pixel number and the vertical effective pixel number is less than or equal to a second threshold.

For different images belonging to the same stream, the video processing device can increase the number of vertical blanking pixels in the video timing so that the duration of the blanking period determined by the number of vertical blanking pixels adjusted by the video processing device is increased. The duration for which the video processing device lights up the backlight for the image to be displayed is increased, which is beneficial to improving the display brightness of the image and the display effect of the video to which the image belongs.

In an optional implementation, the image display method provided by the present application further includes: the video processing device turns off the backlight during the second validity period according to the updated video timing. Usually, the total display time (first time) of a single frame image is short, and the video processing device turns off the backlight during the second validity period. Relying on the visual persistence characteristics of the human eye, the second image is still displayed during the second validity period, avoiding the problem of poor video display effect caused by turning off the backlight.

In an optional implementation, before the video processing device turns on the backlight for the second image to be displayed in the second blanking period, the image display method provided by the present application further includes: the video processing device obtains the display capability of the image source screen, and if the display capability of the image source screen supports the updated video timing, the video processing device turns on the backlight for the second image to be displayed in the second blanking period. The image source screen is used to display an image according to the light source provided by the backlight, and the display capability of the image source screen indicates that the image source screen can support the video timing of the displayed video. Before the video processing device uses the image display method provided by the present application, the video processing device can also analyze the display capability of the image source screen. Only when the display capability of the image source screen supports the updated video timing, the video processing device turns on the backlight for the second image in the second blanking period, thereby avoiding the problem of garbled characters or image overlap in the display process of the second image due to insufficient display capability (hardware capability) of the image source screen, which is conducive to improving the display effect of the image.

In a second aspect, the present application provides an image display device. The image display device includes a module or unit that executes the first aspect or any optional implementation method of the first aspect. Exemplarily, the image display device includes: an acquisition module, a timing module, and a control module. The acquisition module is used to acquire the video timing of the displayed first image, and the video timing indicates: the first blanking period for lighting the backlight for the first image and the first valid period for turning off the backlight, and the sum of the duration of the first blanking period and the first valid period is the first duration. The timing module is used to update the video timing according to the set first threshold value, and acquire the updated video timing; the updated video timing indicates: the second blanking period and the second valid period, the difference between the duration of the second blanking period and the second valid period is less than or equal to the first threshold, and the sum of the duration of the second blanking period and the second valid period is the first duration. The control module is used to light the backlight for the second image to be displayed in the second blanking period according to the updated video timing.

Optionally, the video timing of the first image further indicates: a first pixel clock frequency for lighting the backlight for the first image; and the updated video timing further indicates: a second pixel clock frequency for lighting the backlight for the second image. The second pixel clock frequency is greater than the first pixel clock frequency.

Optionally, the first image and the second image belong to a first stream, and the screen refresh rate corresponding to the first stream is a first value. The video timing of the first image includes: a first vertical blanking pixel number and a vertical effective pixel number used to display the first image, and the first value, the first vertical blanking pixel number and the vertical effective pixel number are used to determine a first blanking period and a first effective period; the updated video timing includes: a second vertical blanking pixel number and a vertical effective pixel number used to display the second image, and the first value, the second vertical blanking pixel number and the vertical effective pixel number are used to determine a second blanking period and a second effective period. The second vertical blanking pixel number is greater than the first vertical blanking pixel number, and the difference between the second vertical blanking pixel number and the vertical effective pixel number is less than or equal to a second threshold.

Optionally, the control module is further used to: turn off the backlight within the second validity period according to the updated video timing.

Optionally, the acquisition module is further used to: acquire the display capability of the image source screen, the image source screen is used to display the image according to the light source provided by the backlight, and the display capability indicates the video timing of the video that the image source screen can support to display. If the display capability of the image source screen supports the updated video timing, the control module lights up the backlight for the second image to be displayed during the second blanking period.

In a third aspect, the present application provides a video processing device. The video processing device includes: a communication interface and a controller. The communication interface is used to receive a bit stream of a video to be displayed; the controller is used to parse the bit stream to implement the operation steps of the method of the first aspect or any optional implementation method of the first aspect.

Exemplarily, the video processing device may be a set-top box, a TV box, a smart TV, a smart screen, a smart projector, or other device for providing a video source.

In a fourth aspect, the present application provides a display device. The display device includes: a processor and an imaging unit. The processor is used to parse the bit stream of the video to be displayed, and implement the operation steps of the method of the first aspect or any optional implementation method of the first aspect. The imaging unit is used to display the reconstructed image of the aforementioned bit stream according to the backlight lit by the processor.

Exemplarily, the display device may be, but is not limited to: a smart TV, a smart screen, a home projector, a cinema projector, a car head-up display (HUD), etc., or a micro-projection system, etc.

In a fifth aspect, the present application provides a display system. The display system includes: an image source screen and a video processing device provided in the third aspect; the image source screen is used to display a reconstructed image of a bit stream according to a backlight lit by the video processing device. For example, the display system is a projection system for a cinema, a smart TV with communication function, a smart screen, or a car HUD, etc., or a system including the above products, etc.

In a sixth aspect, the present application provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the operation steps of the method of the first aspect or any optional implementation manner of the first aspect are implemented.

In a seventh aspect, the present application provides a computer program product. When the computer program product is run on a processor, the processor is caused to execute the operation steps of the method described in the first aspect or any optional implementation of the first aspect.

Regarding the beneficial effects of any of the second to seventh aspects above, reference may be made to the description of the first aspect or any optional implementation of the first aspect, and no further description is given here. Based on the implementations provided in the above aspects, this application can also be further combined to provide more implementations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the structure of a display system provided by the present application;

FIG2A is a schematic diagram 1 of an image display provided by the present application;

FIG2B is a second schematic diagram of an image display provided by the present application;

FIG3 is a schematic diagram of an image transmission provided by the present application;

FIG4 is a flowchart diagram 1 of an image display method provided by the present application;

FIG5 is a second flow chart of an image display method provided by the present application;

FIG6 is a schematic diagram of a video timing comparison provided by the present application;

FIG. 7 is a schematic diagram of the structure of the image display device provided in the present application.

DETAILED DESCRIPTION

The technical solutions involved in this application may be applied not only to the high definition multimedia interface (HDMI) protocol, but also to the display port (DP) protocol, and may also be applied to the future HDMI protocol or DP protocol, etc. The terms used in the implementation method of this application are only used to explain the specific embodiments of this application, and are not intended to limit this application.

The following is a brief introduction to some concepts that may be involved in this application.

Binocular parallax is an important way to achieve stereoscopic display. Binocular parallax uses the characteristics of human visual displacement and visual persistence. By accurately projecting images with left and right eye information to the left and right eyes of the person, the viewer receives two images at the same time, and uses the brain to resolve these images with parallax to achieve a stereoscopic effect.

Naked-eye stereoscopic display refers to a display technology that allows viewers to experience stereoscopic display without wearing any auxiliary equipment. Its mainstream technical paths include directional backlight technology, cylindrical lens technology, light barrier technology, etc. The principle is to use lenses or gratings to make light produce precise directionality and project it to the left and right eyes of a person to produce binocular time difference. Among them, directional backlight technology requires time-division refresh of liquid crystal and backlight rotation to produce left and right eye images. In order to avoid flickering, the screen refresh frequency (screen refresh rate) is generally 120 Hertz (Hz) or above.

Video contains multiple continuous images. When the continuous images change more than 24 frames per second, according to the principle of visual persistence, the human eye cannot distinguish a single static picture, and the smooth and continuous multiple pictures are video. In the field of video coding, the terms "picture", "frame" or "image" can be used as synonyms.

Bitstream (data rate) refers to the binary stream generated after encoding an image or video. Bitstream is also called code stream or code rate, which is the number of bits transmitted per unit time. It is an important part of picture quality control in image coding. For images of the same resolution, the larger the image bitstream, the smaller the compression ratio and the better the picture quality.

The implementation methods of the present application are described below with reference to the accompanying drawings.

1 is a schematic diagram of the structure of a display system provided by the present application, and the display system includes: a human eye detector 110 , an image source 120 , a controller 130 , a controllable backlight unit 140 , an optical lens 150 and an image source screen 160 .

The eye detector 110 is used to obtain eye information of the viewer, which includes horizontal, vertical and depth information. For example, the eye detector 110 may be a depth camera or other types of sensors.

Image source 120, a device for providing a standard stereoscopic video stream, can be a device of any form, including but not limited to: a personal computer (PC), a mobile phone, a tablet computer or a smart camera and other devices with video stream processing functions. For example, the image source 120 is any type of source video generation device, such as a computer graphics processor for generating computer animation scenes or any type of device for acquiring and/or providing source video, computer-generated source video. Image source 120 can be any type of memory or storage for storing the above-mentioned source video. The above-mentioned source video can include multiple video streams (bit streams) or images acquired by multiple video acquisition devices (such as cameras).

The controller 130 is the computing core and control core of the display system. It is used to adjust the video timing provided by the image source 120 and input the new timing video to the image source screen 160. In addition, the controller 130 can also combine the human eye information (such as the position of the human eye) input by the human eye detector 110 to turn on the backlight unit at the corresponding position in the controllable backlight unit 140. Exemplarily, the controller 130 can be a very large-scale integrated circuit. The controller 130 is installed with an operating system and other software programs, so that the controller 130 can access the image source 120 and various peripheral component interconnect express (PCIe) devices. The controller 130 includes one or more processor cores. The processor core in the controller 130 is, for example, a central processing unit (CPU) or other application specific integrated circuit (ASIC). The controller 130 may also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA), or any other programmable logic devices that provide video protocol interfaces such as HDMI/DP, discrete gate or transistor logic devices, discrete hardware components, etc. In practical applications, the display system may also include multiple controllers 130.

The controllable backlight unit 140 is used to provide a light source for the display system. For example, the controllable backlight unit 140 may include, but is not limited to, a light-emitting diode (LED) light source, Mini-LED, Micro LED, an organic light-emitting diode (OLED) or other types of controllable light sources.

The optical lens 150 makes the light provided by the controllable backlight unit 140 directional and can be projected to the positions of the two eyes, such as the left eye or the right eye in FIG. 1. For example, the optical lens 150 can be, but is not limited to, a Fresnel lens, also known as a spiral lens. The Fresnel lens is mostly a thin sheet made of polyolefin material injection molding, and can also be made of glass. One side of the lens surface is smooth, and the other side is engraved with concentric circles from small to large. Its texture is designed according to the interference and perturbation of light, as well as the relative sensitivity and receiving angle requirements.

The image source screen 160 is used to provide a time-division refreshed display image, and sequentially loads the left eye image and the right eye image. The image source screen 160 does not emit light, so a controllable backlight unit 140 is required to provide a light source, such as the image source screen 160 is a liquid crystal display (LCD).

It is worth noting that the display system shown in FIG. 1 may include more or fewer devices, which is not limited in the present application.

In a first optional implementation, when the display system includes at least a controller 130 and a communication interface, the display system may also be referred to as a video processing device. For example, the communication interface may be implemented by an interface circuit, such as the communication interface is used to implement communication between the video processing device and an external device or component. In this embodiment, the communication interface is used to exchange data with other devices (such as the image source screen 160, the image source 120, etc.). The description of the controller 130 may refer to the relevant contents of the aforementioned embodiment, and will not be repeated here.

Exemplarily, the video processing device may include but is not limited to: a set-top box, a TV box, a smart TV, a smart screen, a smart projector, or other devices for providing video sources.

In a second optional implementation, when the display system includes at least the controller 130 and the imaging unit, the display system may also be referred to as a display device. For example, the imaging unit may include the controllable backlight unit 140, the optical lens 150, and the image source screen 160 shown in FIG1 . For another example, the imaging unit may refer to a projection unit, which includes the controllable backlight unit 140 and the optical lens 150 shown in FIG1 .

Exemplarily, the display device may be, but is not limited to: a smart TV, a smart screen, a home projector, a cinema projector, a car HUD, or a micro-projection system, etc.

For example, when the video processing device includes an imaging unit or an image source screen, the video processing device may also be referred to as a display device.

In a feasible scenario, the components included in the display system provided in FIG1 may be integrated into a physical device. When the display system is integrated into a physical device, the physical device may be a smart TV or a smart screen, etc.

In another feasible scenario, the components included in the display system provided in FIG. 1 may be independently configured or partially integrated. For example, the human eye detector 110, the image source 120, the controller 130, the controllable backlight unit 140, the optical lens 150, and the image source screen 160 may be independently configured. In another example, the human eye detector 110, the image source 120, and the controller 130 may be integrated on one physical device, and the controllable backlight unit 140, the optical lens 150, and the image source screen 160 may be integrated on another physical device.

In conjunction with the display system shown in FIG. 1 , the following FIGS. 2A and 2B provide display effect diagrams of a left-eye image and a right-eye image, respectively.

FIG2A is a schematic diagram of an image display provided by the present application. The controllable backlight unit in FIG2A can be used to implement the function of the controllable backlight unit 140 in FIG1 , the lens in FIG2A can be used to implement the function of the optical lens 150 in FIG1 , and the pixel (unit) in FIG2A can be used to implement the function of the image source screen 160 in FIG1 , which will not be described in detail here. In FIG2A , when the controller detects that the left eye image is displayed at the current time, the controller turns on the controllable backlight unit corresponding to the left eye according to the position of the human eye. Accordingly, the left eye receives the image, while the right eye does not receive the image; the image here refers to the image that the human eye can effectively receive and present.

FIG2B is a second schematic diagram of an image display provided by the present application. The hardware used in FIG2B is the same as that in FIG2A, except that: in FIG2B, when the controller detects that the right eye image is displayed at the current time, the controller turns on the controllable backlight unit corresponding to the right eye according to the position of the human eye. Accordingly, the right eye receives the image, while the left eye does not receive the image; the image here refers to the image that the human eye can effectively receive and present.

In combination with the image display solutions provided in Figures 2A and 2B, the controller loads the left and right eye images to the image source screen (pixels) in sequence, and turns on the controllable backlight unit synchronously, so that the display system sequentially presents the left eye image + left backlight on, the right eye image + right backlight in time division, and at the same time turns on the controllable backlight unit at the corresponding position according to the position of the human eye, thereby realizing a movable directional backlight stereoscopic display for the viewer.

With respect to the method of loading left and right eye images provided in FIG. 2A and FIG. 2B , the following provides a video timing (video time) that is used only when the video stream to which the left and right eye images belong is transmitted using the HDMI protocol, and FIG. 3 is a schematic diagram of an image transmission provided by the present application. As shown in FIG. 3 , the HDMI transmission phase can be divided into a blanking period and an active period. Among them, the blanking period includes the Vblanking part at the top of FIG. 3 and the Hblanking part on the left; the active period includes the dark area on the lower right side of FIG. 3 .

The pixels transmitted in the active period are the pixels that the image source screen actually displays. Usually, the pixels that are actually displayed are called image resolution or screen resolution. For example, the actual display pixels of the image transmitted in Figure 3 are 720×480.

During the blanking period, synchronization or control commands such as horizontal synchronization (HSYNC) and vertical synchronization (VSYNC) are transmitted.

The total pixels of the image to be transmitted in FIG3 are 858×525, where 858 are horizontal pixels (add lines) and 525 are vertical pixels (total pixels). Among them, the horizontal active pixels (active lines) are 720 and the vertical active pixels (active pixels) are 480.

When describing the video timing of a video, the video timing information includes: the horizontal blanking pixel number (H blankpixel), the horizontal effective pixel number (H active pixel), and the horizontal total pixel number (H total pixel) determined by adding the horizontal blanking pixel number and the horizontal effective pixel number; the vertical blanking pixel number (V blank line), the vertical effective pixel number (V active line), and the vertical total pixel number (V total line) determined by adding the vertical blanking pixel number and the vertical effective pixel number; and the pixel clock frequency (pixel clock) and the refresh rate (refresh rate).

In some possible examples, the horizontal blanking pixel number is also called the line blanking pixel number, the horizontal effective pixel number is also called the line effective pixel number, and the horizontal total pixel number is also called the line total pixel number; the vertical blanking pixel number is also called the field blanking pixel number, the vertical effective pixel number is also called the field effective pixel number, and the vertical total pixel number is also called the field total pixel number.

The relationship between the parameters included in the video timing information includes:

V total line＝ V blank line + V blank line formula (1)

H total pixel＝ H blank pixel+ H active pixel formula (2)

pixel clock＝ V total line × H total pixel × refresh rate formula (3)

Among them, refresh rate, V blank line and V active line are used to determine the blanking period and active period in the video timing.

The image display method provided in the present application is described in detail below by taking the display system being a video processing device as an example.

FIG4 is a flowchart of an image display method provided by the present application. The image display method is executed by a video processing device, which at least includes a controller and a communication interface. The specific content of the video processing device may refer to the relevant description of FIG1. In FIG4, image 1 may be referred to as a first image, image 2 may be referred to as a second image, blanking period 2 may be referred to as a second blanking period, and valid period 2 may be referred to as a second valid period.

As shown in FIG. 4 , the image display method provided in the embodiment of the present application may include the following steps S410 to S440 .

S410 , the video processing device obtains the video timing of the displayed image 1 .

The displayed video timing indication of the image 1 includes: a blanking period 1 for turning on the backlight of the image 1 and an effective period 1 for turning off the backlight; the sum of the durations of the blanking period 1 and the effective period 1 is the first duration.

S420: The video processing device updates the video timing according to the set first threshold value, and obtains the updated video timing.

Among them, the updated video timing indication is: blanking period 2 and valid period 2, the difference between the duration of blanking period 2 and valid period 2 is less than or equal to the first threshold, and the sum of the duration of blanking period 2 and valid period 2 is the first duration.

In a possible example, taking the case where image 1 and image 2 to be displayed belong to a video with a screen refresh rate of 120 Hz, the following Table 1 shows a possible example before and after the video timing is updated, in milliseconds (ms).

Table 1

The total duration is determined according to the screen refresh rate, 1s/120Hz≈8.33ms. The durations of the blanking period 2 and the valid period 2 provided in Table 1 above are only examples provided in this embodiment and should not be construed as limiting the present application.

As a feasible implementation, the first threshold value may be determined according to the screen refresh rate. For example, if the screen refresh rate is 120 Hz and the display duration of each frame is 8.33 ms, the first threshold value may be 0.33 ms, 0.2 ms, or 0.5 ms.

The following is a detailed example description of the video timing before and after the update in conjunction with the relevant description of FIG. 3 .

The video timing of image 1 also indicates: a first pixel clock frequency for lighting the backlight for image 1. The updated video timing also indicates: a second pixel clock frequency for lighting the backlight for image 2. The second pixel clock frequency is greater than the first pixel clock frequency.

The pixel clock frequency is also called the pixel scanning frequency, which indicates the number of pixel scanning cycles included in a unit time. The video processing device can determine the scanning time of each horizontal pixel according to the pixel clock frequency. For example, if the pixel clock frequency is 297 million Hertz (MHz), the scanning time of each horizontal pixel is 1/297MHz≈3.4 nanoseconds (ns).

In the present application, the video processing device updates the video timing so that in the updated video timing, while the number of pixels output each time remains unchanged, the pixel clock frequency (pixel clock, PCLK) increases, thereby increasing the number of pixels that the video processing device can output per unit time, which is beneficial to maintaining the screen refresh rate of the video timing before and after the update, and avoiding the problem of a reduced screen refresh rate of the video due to the unchanged pixel clock frequency in the video timing before and after the update.

In FIG4, image 1 and image 2 belong to the same video stream (e.g., first stream), and the screen refresh rate corresponding to the first stream is a first value. In conjunction with the relevant contents of FIG3, it can be seen that the length of the blanking period is associated with the number of vertical blanking pixels included in the video timing; the following is an example of the video timing of image 1 and the contents included in the updated video timing in conjunction with the relevant contents of Table 1.

The video timing of image 1 includes: a first vertical blanking pixel number and a vertical effective pixel number used to display image 1. The first value, the first vertical blanking pixel number and the vertical effective pixel number are used to determine blanking period 1 and effective period 1.

The updated video timing includes: a second vertical blanking pixel number and a vertical effective pixel number used to display image 2. The first value, the second vertical blanking pixel number and the vertical effective pixel number are used to determine blanking period 2 and effective period 2.

It is worth noting that the second vertical blanking pixel number is greater than the first vertical blanking pixel number, and the difference between the second vertical blanking pixel number and the vertical effective pixel number is less than or equal to the second threshold value. When the display duration of each frame image remains unchanged, the more vertical blanking pixels there are, the longer the blanking period is; the fewer vertical blanking pixels there are, the shorter the blanking period is.

In some possible implementations, the proportion of the blanking period in the display time of each frame of the image will affect two indicators: the specific liquid crystal flip time and the liquid crystal crosstalk rate in the image source screen. For the adjustment method of the blanking period in the video timing, some possible implementations are provided below.

The following takes the video timing of Image 1 as 1920×1080@120 (CEA-861 standard timing) as an example to describe the updating process of the video timing in detail. 1920×1080 is the actual display pixel, and 120 is the screen refresh rate.

For the video timing Timing Name=1920×1080@120, the following Table 2 shows the contents included in the video timing of the image 1.

Table 2

Among them, the duration of the active period 1 is V active lines→8ms; the duration of the blanking period 1 is V blank lines→0.33ms.

In the first feasible example, during the video timing update process, the video processing device increases the number of vertical blanking pixels in the video timing, such as from 45 in Table 2 to 1080, thereby increasing the length of the blanking period. At this time, if the same pixel clock frequency of 297MHz is sent, the display time of a frame of image will double, making the screen refresh rate about 60Hz. At this time, in order to maintain the original 120Hz unchanged, it is only necessary to increase the pixel clock frequency. After calculation, the pixel clock should be increased from 297MHz to 570MHz. The following Table 3 shows the contents of the updated video timing.

Table 3

Among them, the duration of the active period 2 is V active lines→4.165ms; the duration of the blanking period 2 is V blanklines→4.165ms.

It is worth noting that since the pixel clock frequency in the video timing is adjusted from 279MHz to 570MHz, the video processing device can also check whether the HDMI cable can support the transmission of the bit stream corresponding to the video. For example, for the HDMI2.1 protocol, the maximum pixel clock frequency supported by the screen refresh rate of 120Hz is 600MHz, 600MHz＞570MHz, and the video processing device confirms that the HDMI cable can support the transmission of the bit stream of the video displayed using the updated video timing.

In the second feasible example, during the video timing update process, when the video processing device determines that the image source screen uses a liquid crystal with a flip time of 4ms, the video processing device can set the target duration of the blanking period to 4ms, thereby achieving theoretically zero field of view crosstalk. The updated video timing is shown in Table 4 below.

Table 4

To adjust the blanking period to 4ms, the video processing device determines that V blank lines is 998 and the updated pixel clock is 549MHz. The backlight is turned on or off according to the updated video timing, which can achieve theoretically zero crosstalk.

The video processing device can also set a feasible reference value for V blank lines according to the performance index of the crosstalk rate. For example, in the process of stereoscopic display, if the crosstalk rate is less than or equal to 5%, a better video viewing effect can be achieved, and the blanking period is adjusted within the range of 4ms (1±5%); accordingly, V blank lines (vertical blanking pixel number) can also be adjusted within the range of 998 (1±5%).

Tables 2 to 4 above are used to illustrate the video timing change for a bitstream with a video timing Timing Name = 1920×1080@120. Tables 5 and 6 below are used to illustrate the video timing Timing Name = 1920×1080@240 (CVT-RBv2 standard timing). Table 5 shows the video timing before the update, and Table 6 shows the video timing after the update.

Table 5

Among them, the duration of the active period 1 is V active lines→3.34ms; the duration of the blanking period 1 is V blanklines→0.83ms.

During the video timing update process, the number of vertical blanking pixels in the video timing is increased, such as from 149 in Table 5 to 1080, thereby increasing the length of the blanking period. At this time, if the same pixel clock frequency of 647.5MHz is sent, the display time of a frame of image will double, making the screen refresh rate about 120Hz. At this time, in order to maintain the original 240Hz unchanged, it is only necessary to increase the pixel clock frequency. After calculation, the pixel clock should be increased from 647.5MHz to 1037MHz. The following Table 6 shows the contents of the updated video timing.

Table 6

Among them, the duration of the active period 1 is V active lines→2.08ms; the duration of the blanking period 1 is V blanklines→2.09ms.

The examples provided in Tables 2 to 6 above are only possible implementations provided in this embodiment and should not be construed as limiting the present application. It is worth noting that:

In the present application, for different images belonging to the same stream, the video processing device can increase the number of vertical blanking pixels in the video timing so that the duration of the blanking period determined by the number of vertical blanking pixels adjusted by the video processing device is increased, and the duration for the video processing device to light the backlight for the image to be displayed is increased, which is beneficial to improving the display brightness of the image and the display effect of the video to which the image belongs.

S430, the video processing device turns on the backlight for the image 2 to be displayed in the blanking period 2 according to the updated video timing.

As described in conjunction with Table 1, the video processing device turns on the backlight for image 2 within 4.16 ms.

Regarding the implementation method of lighting the backlight of the video processing device, several possible examples are provided below.

In a first possible example, when the video processing device includes a controller and a communication interface but does not include a controllable backlight unit, the video processing device sends a control signal to the controllable backlight unit, which instructs the controllable backlight unit to light up the backlight for image 2 during blanking period 2.

In a second possible example, when the video processing device includes a controller-controllable backlight unit, the video processing device sends a control signal to the controllable backlight unit, where the control signal instructs the controllable backlight unit to light up the backlight for the image 2 during the blanking period 2 .

In a third possible example, when the video processing device includes a controller, a controllable backlight unit and an image source screen, the controllable backlight unit turns on the backlight for image 2 during blanking period 2 according to the instruction of the controller, and displays image 2 through the image source screen.

The above possible examples are merely optional implementations provided in this embodiment and should not be construed as limitations on the present application.

The video processing device adjusts the video timing used to display the image, so that the duration of the blanking period and the duration of the effective period tend to be close or consistent, while the total display time of each frame of the image is the same and the difference between the duration of the blanking period and the effective period in the adjusted video timing is less than or equal to a threshold, thereby reducing the liquid crystal crosstalk rate caused by liquid crystal flipping.

Furthermore, compared to the problem of a shorter backlighting time due to a shorter blanking period, since the duration of the blanking period and the effective period tend to be close or consistent, when the total display time of each frame of the image is the same, the duration of the blanking period increases and the time the video processing device turns on the backlight increases, which is beneficial to improving the display brightness of the image and the display effect of the video to which the image belongs.

S440, the video processing device turns off the backlight within the validity period 2 according to the updated video timing.

Usually, the total display time (first time) of a single frame image is short, and the video processing device turns off the backlight within the validity period 2. Relying on the visual persistence characteristics of the human eye, image 2 can still be displayed within the validity period 2, avoiding the problem of deterioration of video display effect caused by turning off the backlight.

In some optional situations, the image source screen cannot support the updated video timing, resulting in a poor display effect of the video. To solve this problem, the present application provides a feasible implementation method: the video processing device obtains the display capability of the image source screen, and the display capability indicates that the image source screen can support the video timing of the displayed video; and when the display capability of the image source screen supports the updated video timing, the video processing device lights up the backlight for the image 2 to be displayed during the blanking period 2.

In conjunction with the accompanying drawings, the video processing device is illustrated with examples of the display capability of obtaining the image source screen, and FIG5 is a flowchart of an image display method provided by the present application. In FIG5, the video processing device includes: a playback source (displayer) 510, an image data buffer (image data buffer) 520, an LCD interface (LCD interface) driving unit 530, a liquid crystal display unit 540, a control processing (controler) unit 550 and a video timing controller (video timing generator) 560.

The playback source 510 can be used to implement the function of the image source 120 in FIG. 1 , and the image data buffer 520 is used to temporarily store the video to be displayed. The LCD interface driver unit 530 is used to control the synchronization or control command of the liquid crystal display unit 540, such as the VSYNC command or the HSYNC command in FIG. 3 , or the pixel clock signal corresponding to the pixel clock frequency. In addition, the LCD interface driver unit 530 can also be used to detect the video timing of the video played in the liquid crystal display unit 540.

The liquid crystal display unit 540 may be an LCD screen, which can be used to implement the function of the image source screen 160 in Figure 1. The control processing unit 550 and the video timing controller 560 can be used to implement the function of the controller 130 in Figure 1, which will not be described in detail here.

The control processing unit 550 obtains relevant information of the liquid crystal display unit 540 through the LCD interface driving unit 530, and after identifying the HDMII video stream format of the liquid crystal display unit 540, passes the relevant information to the video timing controller 560, thereby updating the video timing to control the output of the image.

Please continue to refer to FIG. 5 . The image display method provided in this embodiment includes the following steps ① to ⑤.

Step ①, the control processing unit 550 obtains LCD extended display identification data (extended display identification data, EDID).

For example, the LCD EDID has 128 bytes, which contain parameters about the display (liquid crystal display unit 540) and its performance, including vendor information, maximum image size, color settings, factory presets, frequency range limitations, and strings of display name and serial number, etc.

Step ②, the control processing unit 550 parses the acquired LCD EDID to determine the video timing of the displayed image 1; the video timing controller 560 configures the video timing of the image 1 determined by the control processing unit 550 according to the default value.

For example, the default values include a given duration of the blanking period (eg, 4 ms) or an initial value of the number of vertical blanking pixels (eg, 500).

Step ③: The video timing controller 560 adjusts the video timing in a step-by-step manner.

For example, the video timing controller 560 gradually increases the number of vertical blanking pixels based on the initial value of the number of vertical blanking pixels so that the liquid crystal crosstalk rate reaches the standard (such as 5%). The number of vertical blanking pixels increased each time can be 1, 2 or other values, and the value can be set or modified according to user needs.

Step ④: The control processing unit 550 determines whether the LCD link interface meets the display condition.

If satisfied, return to step ③; if not satisfied, execute step ⑤.

The control processing unit 550 determines whether the LCD link interface meets the display conditions, which means: if the display capability of the liquid crystal display unit 540 can support the updated video timing, it is satisfied; if the display capability of the liquid crystal display unit 540 cannot support the updated video timing, it is not satisfied.

Step ⑤: The video timing controller 560 determines the number of vertical blanking pixels.

For example, the video timing controller 560 sets the number of vertical blanking pixels to the last normal working value. The last normal working value refers to the maximum value of the number of vertical blanking pixels when the number of vertical blanking pixels is increased in a stepwise manner so that the display capability of the liquid crystal display unit 540 can support the updated video timing.

In this embodiment, after the video processing device determines the number of vertical blanking pixels, it can update the existing video timing according to the relevant formula in FIG. 3 , thereby obtaining the updated video timing.

It is worth noting that in the 3D naked-eye display process, the left and right eye images need to be transmitted in time-sharing, and the backlight (such as LED) display corresponding to the left and right eye images needs to be switched on and off in time-sharing. By adaptively adjusting the pixel clock frequency and the V Blank part in the video timing, there is sufficient time for the LED liquid crystal flipping + backlight lighting, thereby reducing the liquid crystal crosstalk, improving the image display brightness and enhancing the video display effect.

The following is an example of the video timing before and after the update and the corresponding backlight lighting time in conjunction with the accompanying drawings. FIG6 is a comparison diagram of a video timing provided by the present application. As shown in FIG6, before the video timing is updated, in the display duration of each frame of the image, the backlight is only lit during the shorter blanking period 1, and the backlight lighting duration is short, resulting in a decrease in the display brightness of the single-frame image. After the video timing is updated, the display duration of each frame of the image remains unchanged, the duration of the blanking period 1 increases, and the duration of the backlight lighting increases, which increases the display brightness of the single-frame image and enhances the display effect of the video.

FIG6 is only a possible example of the video timing provided by this embodiment and should not be construed as a limitation on the present application.

It is understandable that, in order to implement the functions in the above-mentioned embodiments, the video processing device includes hardware structures and/or software modules corresponding to the execution of each function. Those skilled in the art should easily realize that, in combination with the units and method steps of each example described in the embodiments disclosed in this application, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application scenario and design constraints of the technical solution.

The above drawings describe in detail the image display method provided according to the embodiment of the present application. The following will describe the image display device provided according to the embodiment of the present application in conjunction with FIG. 7 .

FIG7 is a schematic diagram of the structure of the image display device provided by the present application. These image display devices can be used to implement the functions of the video processing device in the above method embodiment, and thus can also achieve the beneficial effects possessed by the above method embodiment. In this embodiment, the image display device can be a display system as shown in FIG1, or can be a video processing device or display device described in other figures. The association and distinction between the video processing device, the display device and the display system can be referred to the relevant description of FIG1, which will not be repeated here.

As shown in Fig. 7, the image display device 700 includes an acquisition module 710, a timing module 720 and a control module 730. The image display device 700 is used to implement the functions of the video processing device in the method embodiment shown in the above figures.

The acquisition module 710 is used to acquire the video timing of the displayed first image, and the video timing indicates: a first blanking period for lighting the backlight for the first image and a first valid period for turning off the backlight, and the sum of the durations of the first blanking period and the first valid period is the first duration. The timing module 720 is used to update the video timing according to the set first threshold value, and acquire the updated video timing; the updated video timing indicates: a second blanking period and a second valid period, the difference between the durations of the second blanking period and the second valid period is less than or equal to the first threshold value, and the sum of the durations of the second blanking period and the second valid period is the first duration. The control module 730 is used to light the backlight for the second image to be displayed in the second blanking period according to the updated video timing.

It should be understood that the image display device 700 of the embodiment of the present application can be implemented by a chip. The image display device 700 according to the embodiment of the present application can correspond to the method described in the embodiment of the present application, and the above and other operations and/or functions of each unit in the image display device 700 are respectively for implementing the corresponding processes of each method in the aforementioned figures, and for the sake of brevity, they are not repeated here.

The method steps in this embodiment can be implemented by hardware or by a processor executing software instructions. The software instructions can be composed of corresponding software modules, which can be stored in random access memory (RAM), flash memory, read-only memory (ROM), programmable ROM (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), registers, hard disks, mobile hard disks, CD-ROMs, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and the storage medium can be located in an ASIC. In addition, the ASIC can be located in a computing device. Of course, the processor and the storage medium can also exist as discrete components in a network device or a terminal device.

The present application also provides a chip system, which includes a processor for implementing the functions of the video processing device in the above method. In one possible design, the chip system also includes a memory for storing program instructions and/or data. The chip system can be composed of a chip, or can include a chip and other discrete devices.

In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer program or instruction is loaded and executed on a computer, the process or function described in the embodiment of the present application is executed in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, a network device, a user device or other programmable device. The computer program or instruction may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer program or instruction may be transmitted from one website site, computer, server or data center to another website site, computer, server or data center by wired or wireless means. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium may be a magnetic medium, for example, a floppy disk, a hard disk, a tape; it may also be an optical medium, for example, a digital video disc (DVD); it may also be a semiconductor medium, for example, a solid state drive (SSD).

The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims (14)

1. An image display method, the method comprising:

acquiring a video timing of a displayed first image, the video timing indicating: a first blanking period for lighting the backlight for the first image and a first effective period for closing the backlight are added to a first effective period, wherein the sum of the first blanking period and the first effective period is a first duration;

updating the video time sequence according to a set first threshold value, and acquiring an updated video time sequence;

wherein the updated video timing indicates: a second blanking period and a second effective period, a difference in time durations between the second blanking period and the second effective period being less than or equal to the first threshold, and a sum of time durations of the second blanking period and the second effective period being the first time duration;

And according to the updated video time sequence, lighting the backlight for the second image to be displayed in the second blanking period.

2. The method of claim 1, wherein the step of determining the position of the substrate comprises,

The video timing of the first image also indicates: illuminating a backlight for the first image at a first pixel clock frequency;

the updated video timing also indicates: a second pixel clock frequency to illuminate a backlight for the second image;

the second pixel clock frequency is greater than the first pixel clock frequency.

3. The method according to claim 1 or 2, wherein the first image and the second image belong to a first stream, and wherein a screen refresh rate corresponding to the first stream is a first value;

the video timing of the first image includes: a first number of vertical blanking pixels and a number of vertical active pixels employed to display the first image; the first value, the first number of vertical blanking pixels, and the number of vertical significant pixels are used to determine the first blanking period and the first significant period;

The updated video timing comprises: a second number of vertical blanking pixels and the number of vertical significant pixels employed to display the second image; the first value, the second number of vertical blanking pixels, and the number of vertical significant pixels are used to determine the second blanking period and the second significant period;

The second number of vertical blanking pixels is greater than the first number of vertical blanking pixels, and a difference between the second number of vertical blanking pixels and the number of vertical effective pixels is less than or equal to a second threshold.

4. A method according to any one of claims 1-3, characterized in that the method further comprises:

and turning off the backlight in the second validity period according to the updated video time sequence.

5. The method of any of claims 1-4, wherein prior to illuminating a backlight for a second image to be displayed within the second blanking period, the method further comprises:

Acquiring display capability of an image source screen, wherein the image source screen is used for displaying images according to a light source provided by the backlight, and the display capability indicates video time sequences of videos which can be supported to be displayed by the image source screen;

And if the display capability of the image source screen supports the updated video time sequence, lighting the backlight for the second image to be displayed in the second blanking period.

6. An image display device, the device comprising:

an acquisition module for acquiring a video timing of a displayed first image, the video timing indicating: a first blanking period for lighting the backlight for the first image and a first effective period for closing the backlight are added to a first effective period, wherein the sum of the first blanking period and the first effective period is a first duration;

the time sequence module is used for updating the video time sequence according to the set first threshold value and acquiring the updated video time sequence;

wherein the updated video timing indicates: a second blanking period and a second effective period, a difference in time durations between the second blanking period and the second effective period being less than or equal to the first threshold, and a sum of time durations of the second blanking period and the second effective period being the first time duration;

And the control module is used for lighting backlight for the second image to be displayed in the second blanking period according to the updated video time sequence.

7. The apparatus of claim 6, wherein the device comprises a plurality of sensors,

The video timing of the first image also indicates: illuminating a backlight for the first image at a first pixel clock frequency;

the updated video timing also indicates: a second pixel clock frequency to illuminate a backlight for the second image;

the second pixel clock frequency is greater than the first pixel clock frequency.

8. The apparatus of claim 6 or 7, wherein the first image and the second image belong to a first stream, and wherein a screen refresh rate corresponding to the first stream is a first value;

the video timing of the first image includes: a first number of vertical blanking pixels and a number of vertical active pixels employed to display the first image; the first value, the first number of vertical blanking pixels, and the number of vertical significant pixels are used to determine the first blanking period and the first significant period;

The updated video timing comprises: a second number of vertical blanking pixels and the number of vertical significant pixels employed to display the second image; the first value, the second number of vertical blanking pixels, and the number of vertical significant pixels are used to determine the second blanking period and the second significant period;

The second number of vertical blanking pixels is greater than the first number of vertical blanking pixels, and a difference between the second number of vertical blanking pixels and the number of vertical effective pixels is less than or equal to a second threshold.

9. The apparatus of any one of claims 6-8, wherein the control module is further configured to: and turning off the backlight in the second validity period according to the updated video time sequence.

10. The apparatus of any one of claims 6-9, wherein the acquisition module is further configured to: acquiring display capability of an image source screen, wherein the image source screen is used for displaying images according to a light source provided by the backlight, and the display capability indicates video time sequences of videos which can be supported to be displayed by the image source screen;

And if the display capability of the image source screen supports the updated video time sequence, the control module lightens the backlight for the second image to be displayed in the second blanking period.

11. A video processing apparatus, comprising:

A communication interface for receiving a bitstream of a video to be displayed;

a controller for parsing the bitstream, performing the method of any of claims 1-5.

12. A display device, characterized by comprising:

A processor for parsing a bitstream of a video to be displayed, performing the method of any of claims 1-5;

and the imaging unit is used for displaying the reconstructed image of the bit stream according to the backlight lightened by the processor.

13. A display system, comprising: an image source screen and the video processing device of claim 11;

the image source screen is used for displaying the reconstructed image of the bit stream according to the backlight lightened by the video processing equipment.

14. A computer readable storage medium, characterized in that the computer readable storage medium has stored therein a computer program which, when executed by a processor, implements the method of any of claims 1-5.