This application is a continuation of International Application No. PCT/CN2016/111086, filed on Dec. 20, 2016, which claims priority to Chinese Patent Application No. 201511032105.6, filed on Dec. 31, 2015. The disclosures of the aforementioned applications are hereby incorporated by reference in their entireties.
The present invention relates to display technologies, and in particular, to a display driving apparatus and a display driving method.
Currently, liquid crystal displays (LCD) have been widely applied. When an LCD displays image data, a drive voltage is provided to each pixel, so that liquid crystal molecules in the pixel rotate, to change pixel transmittance. Therefore, the pixel can display expected brightness and an expected color. A rotation speed and a rotation angle of the liquid crystal molecule are affected by a drive voltage difference, that is, a larger drive voltage difference indicates a higher rotation speed and a larger rotation angle of the liquid crystal molecule.
When a liquid crystal display panel displays a moving image, to meet a display rate and avoid image ghosting, an overdrive value needs to be provided for a pixel. In this way, when the liquid crystal display panel displays a next frame of image, a liquid crystal molecule can rotate to another angle within a specific time, so as to increase a rotation speed of the liquid crystal molecule.
Currently, an overdrive value of a pixel is in a lookup table (LUT). The LUT records a correspondence between the overdrive value of the pixel and two grayscale values of the pixel in a current frame and a preceding frame. The correspondence is preset. The overdrive value is used as a grayscale value and is displayed on a liquid crystal display panel.
After obtaining the current frame ORG_F2, the decompressed current frame DEC_F2, and the decompressed preceding frame DEC_F1, the data selection unit calculates a compression error of the current frame according to the current frame ORG_F2 and the decompressed current frame DEC_F2, and determines, according to the compression error of the current frame, a first frame F1 and a second frame F2 that are to be sent to the display acceleration unit. The first frame F1 and the second frame F2 each are one of the current frame ORG_F2, the decompressed current frame DEC F2, or the decompressed preceding frame DEC_F1. The display acceleration unit determines an overdrive value according to the first frame F1 and the second frame F2.
It may be learned from the prior art that when a compression error is greater than a threshold, that is, when the compression error is relatively large, a display acceleration unit does not execute an overdrive mechanism, and in this case, the display acceleration unit directly transfers a grayscale value of a pixel in a current frame ORG F2 to a liquid crystal display panel for display. Consequently, display quality is low when the liquid crystal display panel displays a dynamic image. Therefore, the display driving method provided in the prior art has a disadvantage.
According to a display driving apparatus and a display driving method that are provided in embodiments of the present invention, display quality of a dynamic image can be improved.
According to a first aspect, an embodiment of the present invention provides a display driving apparatus, including:
It may be learned from the first aspect that when the data selection unit determines that a current frame correlates with a preceding frame, and the current frame is dynamic relative to the preceding frame, a compensated preceding frame is obtained by means of calculation, and an overdrive value is determined according to the compensated preceding frame and the current frame.
No compression error is involved in an overdrive value determining process, that is, when the compression error is not considered, an overdrive mechanism may be still used to determine a grayscale value of a displayed pixel. Therefore, display quality of a dynamic image is improved.
With reference to the first aspect, in a first implementation of the first aspect, the data selection unit includes:
With reference to the first implementation of the first aspect, in a second implementation of the first aspect, the correlation determining unit includes:
With reference to the first or the second implementation of the first aspect, in a third implementation of the first aspect, the frame determining unit is further configured to:
With reference to the first or the second implementation of the first aspect, in a fourth implementation of the first aspect, the data selection unit further includes an error determining unit, where
It may be learned from the fourth implementation of the first aspect that when a current frame does not correlate with a preceding frame, whether a compression error is greater than an error threshold further needs to be determined. When the compression error is greater than the error threshold, that is, when the error is excessively large in an encoding and decoding process, the current frame is used as a first frame and a second frame, and finally, a grayscale value of a pixel in the current frame is directly output to a liquid crystal display panel for display. Therefore, a relatively large error of a determined overdrive value that is caused by an overdrive mechanism is avoided.
With reference to the first, the second, the third, or the fourth implementation of the first aspect, in a fifth implementation of the first aspect, the frame determining unit is further configured to:
It may be learned from the fifth implementation of the first aspect that when the current frame is static relative to the preceding frame, the two frames are the same, and there is no need to use an overdrive mechanism.
With reference to the first, the second, the third, the fourth, or the fifth implementation of the first aspect, in a sixth implementation of the first aspect, the display acceleration unit includes a lookup table circuit, and the lookup table circuit is configured to determine, according to two grayscale values of a pixel in the first frame and the second frame, an overdrive value corresponding to the pixel.
With reference to the first aspect, in a seventh implementation of the first aspect, the compression and decompression unit includes a compression unit and a decompression unit, where
With reference to the first aspect, in an eighth implementation of the first aspect, the storage unit includes a storage module and a storage management module, where
According to a second aspect, an embodiment of the present invention provides a display apparatus, and the display apparatus includes the display driving apparatus provided in the foregoing embodiment and a liquid crystal display panel, where
With reference to the second aspect, in a first implementation of the second aspect, the display apparatus further includes:
According to a third aspect, an embodiment of the present invention provides a display driving method, and the display driving method includes:
It may be learned from the third aspect that when it is determined that a current frame correlates with a preceding frame, and the current frame is dynamic relative to the preceding frame, a compensated preceding frame is obtained by means of calculation, and an overdrive value is determined according to the compensated preceding frame and the current frame. No compression error is involved in an overdrive value determining process, that is, when the compression error is not considered, an overdrive mechanism may be still used to determine a grayscale value of a displayed pixel. Therefore, display quality of a dynamic image is improved.
With reference to the third aspect, in a first implementation of the third aspect, the obtaining a compensated preceding frame by means of calculation according to the current frame, the decompressed current frame, and the decompressed preceding frame includes:
With reference to the third aspect or the first implementation of the third aspect, in a second implementation of the third aspect, the determining, according to the decompressed current frame and the decompressed preceding frame, whether the current frame correlates with a preceding frame includes:
With reference to the third aspect, or the first or the second implementation of the third aspect, in a third implementation of the third aspect, the display driving method further includes:
With reference to the third aspect, or the first or the second implementation of the third aspect, in a fourth implementation of the third aspect, the display driving method further includes:
With reference to the third aspect, or the first, the second implementation of the third aspect, in a fifth implementation of the third aspect, the display driving method further includes:
With reference to the third aspect, in a sixth implementation of the third aspect, the determining an overdrive value according to the compensated preceding frame and the current frame includes:
With reference to the fourth implementation of the third aspect, in a seventh implementation of the third aspect, the determining an overdrive value according to the decompressed preceding frame and the current frame includes:
To describe the technical solutions in the embodiments of the present invention more clearly, the following briefly describes the accompanying drawings required for describing the embodiments. Apparently, the accompanying drawings in the following description show merely some embodiments of the present invention, and a person of ordinary skill in the art may still derive other drawings from these accompanying drawings without creative efforts.
The following clearly describes the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are merely some but not all of the embodiments of the present invention. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.
Terms involved in the embodiments of the present invention are first described.
A current frame (ORG_F2) is a non-compressed current original frame.
A compressed current frame (COM_F2) is a frame formed after compressing a current frame.
A decompressed current frame (DEC_F2) is a frame formed after decompressing a compressed current frame.
A preceding frame (ORG_F1) is a preceding frame of a current frame instead of a preceding frame of another frame.
A compressed preceding frame (COM_F1) is a frame formed after compressing a preceding frame.
A decompressed preceding frame (DEC_F1) is a frame formed after decompressing a compressed preceding frame.
The following describes in detail the embodiments provided in the present invention.
The compression and decompression unit 11 is configured to: receive a current frame ORG_F2, compress the current frame ORG_F2 to obtain a compressed current frame COM_F2, and transfer the compressed current frame COM_F2 to the storage unit 12 for storage.
The compression and decompression unit 11 is further configured to: decompress the compressed current frame COM_F2 to obtain a decompressed current frame DEC_F2, decompress a compressed preceding frame COM_F1 obtained from the storage unit 12 to obtain a decompressed preceding frame DEC_F1, and send the decompressed current frame DEC_F2 and the decompressed preceding frame DEC_F1 to the data selection unit 13.
Further, the compression and decompression unit 11 includes a compression unit 111 and a decompression unit 112.
The compression unit 111 is configured to: receive the current frame ORG_F2, compress the current frame ORG_F2 to obtain the compressed current frame COM_F2, send the compressed current frame COM_F2 to the decompression unit 112, and send the compressed current frame COM_F2 to the storage unit 12 for storage.
The decompression unit 112 is configured to: receive the compressed current frame COM_F2 sent by the compression unit 111, decompress the compressed current frame COM_F2 to obtain the decompressed current frame DEC_F2, decompress the compressed preceding frame COM_F1 obtained from the storage unit 12 to obtain the decompressed preceding frame DEC_F1, and send the decompressed current frame DEC_F2 and the decompressed preceding frame DEC_F1 to the data selection unit 13.
The storage unit 12 is configured to store a frame compressed by the compression and decompression unit 11. The frame specifically includes the compressed current frame COM_F2 and the compressed preceding frame COM_F1.
Further, the storage unit 12 includes a storage module 121 and a storage management module 122. The storage module 121 is configured to store a compressed frame. The compressed frame includes the compressed current frame COM_F2 and the compressed preceding frame COM_F1. The storage management module 122 is configured to perform storage management, so as to control writing of the compressed frame into the storage module 121 or reading of the compressed frame from the storage module 121.
The data selection unit 13 is configured to: receive the current frame ORG_F2, the decompressed current frame DEC_F2, and the decompressed preceding frame DEC_F1, determine a result of correlation between the current frame ORG_F2 and a preceding frame ORG_F1 and frame status information of the current frame ORG_F2 relative to the preceding frame ORG_F1, and when the result of correlation is that the current frame correlates with the preceding frame, and the frame status information is a dynamic state, obtain a compensated preceding frame by means of calculation according to the current frame ORG_F2, the decompressed current frame DEC_F2, and the decompressed preceding frame DEC_F1, use the compensated preceding frame as a first frame, and use the current frame ORG_F2 as a second frame.
It should be noted that a difference between the compensated preceding frame obtained by means of calculation and the actual preceding frame is allowed.
The correlation determining unit 131 is configured to determine the result of correlation between the current frame ORG_F2 and the preceding frame ORG_F1 according to the decompressed current frame DEC_F2 and the decompressed preceding frame DEC_F1. The result of correlation is that the current frame correlates with the preceding frame or the current frame does not correlate with the preceding frame.
A structure of the correlation determining unit 131 is shown in
The correlation value calculation unit 1311 is configured to calculate a value of correlation between the decompressed current frame DEC_F2 and the decompressed preceding frame DEC_F1. The value of correlation is used to indicate a degree of correlation between the current frame ORG_F2 and the preceding frame ORG_F1, and a larger value of correlation indicates a higher correlation between the frames.
Preferably, the following provides a method for calculating the value of correlation by the correlation value calculation unit 1311: 1. Statistics about a distribution status of values of pixels in the current frame ORG_F2 and statistics about a distribution status of values of pixels in the preceding frame ORG_F1 are separately collected. 2. A value of correlation between the current frame ORG_F2 and the preceding frame ORG_F1 is calculated according to the distribution status of the values of the pixels in the current frame ORG_F2 and the distribution status of the values of the pixels in the preceding frame ORG_F1.
It should be noted that the method for calculating the value of correlation by the correlation value calculation unit 1311 is not specifically limited in the present invention. For a person skilled in the art, a value of correlation between two frames is calculated in multiple implementation methods.
The correlation judgment unit 1312 is configured to compare the value of correlation calculated by the correlation value calculation unit 1311 with a preset correlation threshold to obtain the result of correlation. If the value of correlation is greater than the correlation threshold, the result of correlation is that the current frame correlates with the preceding frame, or otherwise, the result of correlation is that the current frame does not correlate with the preceding frame. The correlation threshold is preset. In addition, different correlation thresholds may be set in different correlation value calculation methods. This is not specifically limited in the present invention.
The status determining unit 132 is configured to compare the decompressed current frame DEC_F2 with the decompressed preceding frame DEC_F1 to determine the frame status information of the current frame ORG_F2 relative to the preceding frame DEC_F1. The frame status information is a dynamic state or a static state.
The calculation unit 134 is configured to: when the result of correlation determined by the correlation determining unit 131 is that the current frame correlates with the preceding frame, and the frame status information determined by the status determining unit 132 is a dynamic state, calculate a difference between the current frame ORG_F2 and the decompressed current frame DEC_F2, multiply the difference by an adjustment factor, and add a result of the multiplication and the decompressed preceding frame DEC_F1 to obtain the compensated preceding frame. The adjustment factor is used to indicate an adjustment amplitude of the difference, a value of the adjustment factor is from 0 to 1, and in a process of calculating the compensated preceding frame, the value of the adjustment factor is an empirical value.
The frame determining unit 133 is configured to: when the result of correlation determined by the correlation determining unit 131 is that the current frame correlates with the preceding frame, and the frame status information determined by the status determining unit 132 is a dynamic state, use the compensated preceding frame obtained by the calculation unit 134 as the first frame, and use the current frame ORG_F2 as the second frame.
Optionally, the frame determining unit 133 is further configured to:
Optionally, the frame determining unit 133 is further configured to:
The embodiment corresponding to
Because the error determining unit 135 is added in the embodiment corresponding to
When the result of correlation determined by the correlation determining unit 131 is that the current frame does not correlate with the preceding frame, the frame determining unit 133 in
Specifically, when the result of correlation determined by the correlation determining unit 131 is that the current frame does not correlate with the preceding frame, the frame status information determined by the status determining unit 132 is a dynamic state, and the error result determined by the error determining unit 135 is that the compression error is greater than the error threshold, the frame determining unit 133 separately uses the current frame ORG_F2 as the first frame and the second frame.
Alternatively, when the result of correlation determined by the correlation determining unit 131 is that the current frame does not correlate with the preceding frame, the frame status information determined by the status determining unit 132 is a dynamic state, and the error result determined by the error determining unit 135 is that the compression error is not greater than the error threshold, the frame determining unit 133 uses the decompressed preceding frame DEC_F1 as the first frame, and uses the current frame ORG_F2 as the second frame.
In addition, when the result of correlation determined by the correlation determining unit 131 is that the current frame correlates with the preceding frame, and the frame status information determined by the status determining unit 132 is a dynamic state, and when the frame status information determined by the status determining unit 132 is a static state, a function implemented by the frame determining unit 133 in
After the data selection unit 13 determines the first frame and the second frame, the data selection unit 13 is further configured to send the first frame and the second frame to the display acceleration unit 14.
The display acceleration unit 14 is configured to determine an overdrive value according to the received first frame and second frame.
Specifically, when the first frame and the second frame are different frames, the display acceleration unit 14 obtains, by querying a lookup table circuit, an overdrive value corresponding to two grayscale values of a pixel in the first frame and the second frame. The lookup table circuit is configured to determine, according to two grayscale values of a pixel in the first frame and the second frame, an overdrive value corresponding to the pixel. In addition, it may be learned from the foregoing description that, that the first frame and the second frame are different frames includes the following two cases: 1. The first frame is the compensated preceding frame, and the second frame is the current frame ORG_F2. 2. The first frame is the decompressed preceding frame DEC_F1, and the second frame is the current frame ORG_F2.
The display acceleration unit 14 is further configured to transfer the determined overdrive value to a liquid crystal display panel for display, and use the determined overdrive value as a grayscale value of a displayed pixel.
Further, when the first frame and the second frame are same frames, the display acceleration unit 14 does not need to determine the overdrive value by querying the lookup table circuit, but directly transfers a grayscale value of a pixel in the current frame ORG_F2 to the liquid crystal display panel for display. This case is the case in which an overdrive mechanism is not executed as mentioned in the background. In addition, it may be learned from the foregoing description that when the first frame and the second frame are same frames, both the first frame and the second frame are the current frame.
In the foregoing embodiment, when the data selection unit determines that a current frame correlates with a preceding frame, and the current frame is dynamic relative to the preceding frame, a compensated preceding frame is obtained by means of calculation, and an overdrive value is determined according to the compensated preceding frame and the current frame. No compression error is involved in an overdrive value determining process, that is, when the compression error is not considered, an overdrive mechanism may be still used to determine a grayscale value of a displayed pixel. Therefore, display quality of a dynamic image is improved.
The display driving apparatus provided in this embodiment of the present invention is used as a hardware apparatus. All units of the display driving apparatus are hardware units, and some units may be implemented by circuits. The display driving apparatus may be used as a separate chip, and is connected to a timing controller (TCON), or may be integrated in a TCON. Whether the display driving apparatus is integrated in a TCON is not limited in the present invention.
The TCON 61 is configured to: generate a current frame, and send the current frame to the display driving apparatus 10.
The display driving apparatus 10 is configured to: receive the current frame, generate an overdrive value, and send the overdrive value to the liquid crystal display panel 62. Specifically, for a structure of the display driving apparatus 10 and a function of each unit included therein, refer to the description of the display driving apparatus 10 in the foregoing embodiment. In this embodiment, the display driving apparatus 10 is not described in detail.
The liquid crystal display panel 62 is configured to receive the overdrive value sent by the display driving apparatus 10, and display the overdrive value.
S71. Determine whether the current frame correlates with the preceding frame.
When the current frame correlates with the preceding frame, S72 is performed; otherwise, S76 is performed.
Specifically, whether the current frame correlates with the preceding frame is determined according to the decompressed current frame and the decompressed preceding frame.
Further, that whether the current frame correlates with the preceding frame is determined according to the decompressed current frame and the decompressed preceding frame includes:
Preferably, the following provides a method for calculating the value of correlation between the decompressed current frame and the decompressed preceding frame: 1. Statistics about a distribution status of values of pixels in the current frame and statistics about a distribution status of values of pixels in the preceding frame are separately collected. 2. A value of correlation between the current frame and the preceding frame is calculated according to the distribution of the values of the pixels in the current frame and the distribution of the values of the pixels in the preceding frame.
It should be noted that the method for calculating the value of correlation is not specifically limited in the present invention. In addition, different correlation thresholds may be used in different correlation value calculation methods. The correlation threshold is a preset value.
S72. Determine whether the current frame is dynamic relative to the preceding frame.
Specifically, the decompressed current frame is compared with the decompressed preceding frame to determine whether the current frame is dynamic relative to the preceding frame.
When the current frame is dynamic relative to the preceding frame, S73 is performed; otherwise, that is, when the current frame is static relative to the preceding frame, S76 is performed.
S73. Obtain a compensated preceding frame by means of calculation.
Specifically, the compensated preceding frame is obtained by means of calculation according to the current frame, the decompressed current frame, and the decompressed preceding frame. Further, a specific calculation method includes:
S74. Determine an overdrive value according to the compensated preceding frame and the current frame.
Specifically, an overdrive value corresponding to two grayscale values of a pixel in the compensated preceding frame and the current frame is determined by querying a lookup table circuit.
S75. Transfer the overdrive value to a liquid crystal display panel for display.
In S75, the determined overdrive value is used as a grayscale value of a displayed pixel.
S76. Transfer a grayscale value of a pixel in the current frame to a liquid crystal display panel for display.
In this embodiment, when it is determined that a current frame correlates with a preceding frame, and the current frame is dynamic relative to the preceding frame, a compensated preceding frame is obtained by means of calculation, and an overdrive value is determined according to the compensated preceding frame and the current frame. No compression error is involved in an overdrive value determining process, that is, when the compression error is not considered, an overdrive mechanism may be still used to determine a grayscale value of a displayed pixel. Therefore, display quality of a dynamic image is improved.
S81. Determine whether the current frame is dynamic relative to the preceding frame.
When the current frame is dynamic relative to the preceding frame, S82 is performed; otherwise, that is, when the current frame is static relative to the preceding frame, S88 is performed.
For how to determine whether the current frame is dynamic relative to the preceding frame, refer to the method provided in the foregoing embodiment. Details are not described in this embodiment.
S82. Determine whether the current frame correlates with the preceding frame.
When the current frame correlates with the preceding frame, S83 is performed; otherwise, that is, when the current frame does not correlate with the preceding frame, S86 is performed.
For how to determine whether the current frame correlates with the preceding frame, refer to the method provided in the foregoing embodiment. Details are not described in this embodiment.
S83. Obtain a compensated preceding frame by means of calculation.
S84. Determine an overdrive value according to the compensated preceding frame and the current frame.
S85. Transfer the overdrive value to a liquid crystal display panel for display.
In S85, the determined overdrive value is used as a grayscale value of a displayed pixel.
A process of performing S83 to S85 is the same as a process of performing S73 to S75 in
S86. Determine whether a compression error of the current frame is greater than an error threshold.
When the compression error of the current frame is not greater than the error threshold, S87 is performed; otherwise, S88 is performed.
S87. Determine an overdrive value according to a decompressed preceding frame and the current frame.
Specifically, an overdrive value corresponding to two grayscale values of a pixel in the decompressed preceding frame and the current frame is determined by querying a lookup table circuit.
S88. Transfer a grayscale value of a pixel in the current frame to a liquid crystal display panel for display.
In this embodiment, when it is determined that a current frame correlates with a preceding frame, and the current frame is dynamic relative to the preceding frame, a compensated preceding frame is obtained by means of calculation, and an overdrive value is determined according to the compensated preceding frame and the current frame. No compression error is involved in an overdrive value determining process, that is, when the compression error is not considered, an overdrive mechanism may be still used to determine a grayscale value of a displayed pixel. Therefore, display quality of a dynamic image is improved.
In the several embodiments provided in this application, it should be understood that the disclosed system, apparatus, and method may be implemented in other manners. For example, the described apparatus embodiment is merely an example. For example, the unit division is merely logical function division and may be other division during actual implementation. For example, a plurality of units or components may be combined or integrated into another system, or some features may be ignored or not performed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections may be implemented by using some interfaces. The indirect couplings or communication connections between the apparatuses or units may be implemented in electronic, mechanical, or other forms.
The foregoing descriptions are merely specific implementations of the present invention, but are not intended to limit the protection scope of the present invention. Any variation or replacement readily figured out by a person skilled in the art within the technical scope disclosed in the present invention shall fall within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201511032105.6 | Dec 2015 | CN | national |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/CN2016/111086 | Dec 2016 | US |
| Child | 16024758 | US |