# US 10,769,039 B2 · Method and apparatus for performing display control of a display panel to display images with aid of dynamic overdrive strength adjustment

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,769,039 B2
- Document ID: US10769039B2
- Status: Granted
- Kind: B2
- Application number: 16/208,507
- Filed: 2018-12-03
- Published: 2020-06-04
- Granted: 2020-09-08
- Earliest claimed: 2018-12-03
- Assignees: Himax Technologies Limited
- Applicants: Himax Technologies Limited
- Inventors: Tung-Ying Wu; Chiu-Yu Chen
- Web page: https://patentgrep.com/patent/US10769039B2

## CPC

- G06F 11/162: {Displays}
- G09G 3/36: using liquid crystals
- G09G 3/22: using controlled light sources
- H04N 19/176: the region being a block, e.g. a macroblock
- H04N 21/4402: involving reformatting operations of video signals for household redistribution, storage or real-time display {(details of conversion of video standards at pixel level H04N7/01; video transcoding H04N19/40; adapting incoming signals to the display format of the display terminal G09G5/005; media handling at the source in data packet switching networks H04L65/764)}
- G09G 2310/0243: Details of the generation of driving signals
- G09G 2340/02: Handling of images in compressed format, e.g. JPEG, MPEG
- G09G 2340/16: Determination of a pixel data signal depending on the signal applied in the previous frame
- G09G 2360/16: Calculation or use of calculated indices related to luminance levels in display data
- G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N)
- G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00)
- H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION

## Abstract

A method and apparatus for performing display control of a display panel to display images with aid of dynamic overdrive (OD) strength adjustment is provided. Each of the images includes a plurality of blocks, each of the plurality of blocks includes a plurality of pixels, and each of the plurality of pixels comprising a plurality of sub-pixels. The method comprising: encoding image data of a current image to generate encoded image data of the current image, wherein the encoded image data is compressed data of the image data; decoding the encoded image data of the current image to generate decoded image data of the current image; performing block error estimation to generate quantized block error values of the plurality of blocks, respectively; determining OD depressed gains, respectively; and adjusting OD strength of corresponding blocks within a next image, respectively, for controlling the display panel to display the next image.

## Claims

### Claim 1

A method for performing display control of a display panel to display images with aid of dynamic overdrive (OD) strength adjustment, each of the images comprising a plurality of blocks, each of the plurality of blocks comprising a plurality of pixels, each of the plurality of pixels comprising a plurality of sub-pixels, the method comprising:
encoding image data of a current image to generate encoded image data of the current image, wherein the encoded image data is compressed data of the image data;
decoding the encoded image data of the current image to generate decoded image data of the current image;
according to the image data and the decoded image data of the current image, performing block error estimation to generate quantized block error values of blocks of the current image, respectively, wherein the quantized block error values represent compression error of the decoded image data caused by encoding;
according to the quantized block error values, determining OD depressed gains, respectively; and
according to the OD depressed gains, adjusting OD strength of corresponding blocks within a next image, respectively, for controlling the display panel to display the next image, wherein the OD depressed gains represent reduction magnification regarding the OD strength.

### Claim 2 (depends on 1)

The method of claim 1, wherein the step of performing block error estimation to generate quantized block error values of the plurality of blocks respectively further comprises:
according to image data of a block of the current image and decoded image data of the block, performing sub-pixel error calculations on sub-pixels within the block to obtain sub-pixel error values of the sub-pixels within the block, respectively, wherein the image data of the current image comprises the image data of the block, and the decoded image data of the current image comprises the decoded image data of the block;
according to the sub-pixel error values, performing pixel error calculations on pixels within the block to obtain pixel error values of pixels within the block, respectively;
according to the pixel error values, performing block error calculation on the block to obtain a block error value of the block; and
quantizing the block error value to obtain a quantized block error value of the block.

### Claim 3 (depends on 2)

The method of claim 2, wherein the step of performing the pixel error calculations on the pixels within the block to obtain the pixel error values of the pixels within the block respectively is performed according to a set of predetermined sub-pixel weightings for the plurality of sub-pixels of the each of the plurality of pixels.

### Claim 4 (depends on 2)

The method of claim 2, wherein the step of performing the block error calculation on the block to obtain the block error value of the block further comprises:
finding a maximum pixel error value, an average pixel error value and a minimum pixel error value of the pixel error values of the pixels within the block;
according to the maximum pixel error value, the average pixel error value and the minimum pixel error value, performing a first error calculation on the block to obtain a temporary block error value; and
according to temporary block error values of the block and adjacent blocks thereof, performing a second error calculation on the block, to obtain the block error value.

### Claim 5 (depends on 4)

The method of claim 4, wherein the step of performing the first error calculation on the block to obtain the temporary block error value is performed according to a set of predetermined error weightings of the maximum pixel error value, the average pixel error value and the minimum pixel error value.

### Claim 6 (depends on 4)

The method of claim 4, wherein the step of performing the second error calculation on the block to obtain the block error value is performed according to a set of predetermined spatial error weightings, wherein the set of predetermined spatial error weightings correspond to temporary block error values of a current block and the adjacent blocks thereof, respectively.

### Claim 7 (depends on 1)

The method of claim 1, wherein the step of determining the OD depressed gains respectively is performed according to a look-up table.

### Claim 8 (depends on 1)

The method of claim 1, wherein the step of adjusting the OD strength of the corresponding blocks within the next image respectively for controlling the display panel to display the next image further comprises:
according to differences between image data values of a block of the corresponding blocks within the next image and OD data values of the block, determining OD shifts of the block, respectively; and
determining depressed OD shifts of the block through multiplying the OD shifts by an OD depressed gain corresponding to the block, respectively;
wherein:
when an image data value of a sub-pixel of the block is less than an OD data value of the sub-pixel, a depressed OD data value of the sub-pixel equals the image data value plus a corresponding depressed OD shift; and
when the image data value of the sub-pixel of the block is greater than the OD data value of the sub-pixel, the depressed OD data value of the sub-pixel equals the image data value minus the corresponding depressed OD shift.

### Claim 9 (depends on 1)

The method of claim 1, wherein the step of adjusting the OD strength of the corresponding blocks within the next image respectively for controlling the display panel to display the next image further comprises:
according to differences between image data values of a block within the current image and OD data values of a corresponding block within the next image, determining OD shifts between the block and the corresponding block, respectively; and
determining depressed OD shifts between the block and the corresponding block through multiplying the OD shifts by an OD depressed gain corresponding to the block, respectively;
wherein:
when an image data value of a sub-pixel of the block is less than an OD data value of a corresponding sub-pixel of the corresponding block, a depressed OD data value of the corresponding sub-pixel equals the image data value of the sub-pixel plus a corresponding depressed OD shift; and
when the image data value of the sub-pixel of the block is greater than the OD data value of the corresponding sub-pixel of the corresponding block, the depressed OD data value of the corresponding sub-pixel equals the image data value of the sub-pixel minus the corresponding depressed OD shift.

### Claim 10 (depends on 9)

The method of claim 9, wherein the step of adjusting the OD strength of the corresponding blocks within the next image respectively for controlling the display panel to display the next image further comprises:
when the image data value of the sub-pixel is less than the OD data value and the depressed OD data value is less than an image data value of the corresponding sub-pixel, replacing the depressed OD data value with a new OD value that is equal to the image data value of the corresponding sub-pixel; and
when the image data value of the sub-pixel is greater than the OD data value and the depressed OD data value is greater than the image data value of the corresponding sub-pixel, replacing the depressed OD data value with a new OD value that is equal to the image data value of the corresponding sub-pixel.

### Claim 11

An apparatus for performing display control of a display panel to display images with aid of dynamic overdrive (OD) strength adjustment, each of the images comprising a plurality of blocks, each of the plurality of blocks comprising a plurality of pixels, each of the plurality of pixels comprising a plurality of sub-pixels, the apparatus comprising:
an encoder, arranged to encode image data of a current image to generate encoded image data of the current image, wherein the encoded image data is compressed data of the image data;
a decoder, arranged to decode the encoded image data of the current image to generate decoded image data of the current image;
a block error processing circuit, arranged to perform block error estimation to generate quantized block error values of blocks of the current image according to the image data and the decoded image data of the current image, respectively, wherein the quantized block error values represent compression error of the decoded image data caused by encoding; and
an OD strength depressing circuit, wherein the OD strength depressing circuit determines OD depressed gains according to the quantized block error values, respectively, and adjusts OD strength of corresponding blocks within a next image according to the OD depressed gains, respectively, for controlling the display panel to display the next image, wherein the OD depressed gains represent reduction magnification regarding the OD strength.

### Claim 12 (depends on 11)

The apparatus of claim 11, wherein:
according to image data of a block of the current image and decoded image data of the block, the block error processing circuit performs sub-pixel error calculations on sub-pixels within the block to obtain sub-pixel error values of the sub-pixels within the blocks, respectively, wherein the image data of the current image comprises the image data of the block, and the decoded image data of the current image comprises the decoded image data of the block;
according to the sub-pixel error values, the block error processing circuit performs pixel error calculations on pixels within the block to obtain pixel error values of pixels within the block, respectively;
according to the pixel error values, the block error processing circuit performs block error calculation on the block to obtain a block error value of the block; and
the block error processing circuit quantizes the block error value to obtain a quantized block error value of the block.

### Claim 13 (depends on 12)

The apparatus of claim 12, wherein the block error processing circuit performs the pixel error calculations on the pixels within the block to obtain the pixel error values of the pixels within the blocks according to a set of predetermined sub-pixel weightings for the plurality of sub-pixels of the each of the plurality of pixels, respectively.

### Claim 14 (depends on 12)

The apparatus of claim 12, wherein:
according to the pixel error values, the block error processing circuit finds a maximum pixel error value, an average pixel error value and a minimum pixel error value of the pixel error values of the pixels within the block;
according to the maximum pixel error value, the average pixel error value and the minimum pixel error value, the block error processing circuit performs a first error calculation on the block to obtain a temporary block error value; and
according to temporary block error values of the block and adjacent blocks thereof, the block error processing circuit performs a second error calculation on the block, to obtain the block error value.

### Claim 15 (depends on 14)

The apparatus of claim 14, wherein the block error processing circuit performs the first error calculation on the block to obtain the temporary block error value according to a set of predetermined error weightings of the maximum pixel error value, the average pixel error value and the minimum pixel error value.

### Claim 16 (depends on 14)

The apparatus of claim 14, wherein the block error processing circuit performs the second error calculation on the block to obtain the block error value according to a set of predetermined spatial error weightings, wherein the set of predetermined spatial error weightings correspond to temporary block error values of a current block and the adjacent blocks thereof, respectively.

### Claim 17 (depends on 11)

The apparatus of claim 11, wherein the OD strength depressing circuit determines the OD depressed gains according to a look-up table, respectively.

### Claim 18 (depends on 11)

The apparatus of claim 11, wherein:
according to differences between image data values of a block of the corresponding blocks within the next image and OD data values of the block, the OD strength depressing circuit determines OD shifts of the block, respectively; and
the OD strength depressing circuit determines depressed OD shifts of the block through multiplying the OD shifts by an OD depressed gain corresponding to the block, respectively;
wherein:
when an image data value of a sub-pixel of the block is less than an OD data value of the sub-pixel, a depressed OD data value of the sub-pixel equals the image data value plus a corresponding depressed OD shift; and
when the image data value of the sub-pixel of the block is greater than the OD data value of the sub-pixel, the depressed OD data value of the sub-pixel equals the image data value minus the corresponding depressed OD shift.

### Claim 19 (depends on 11)

The apparatus of claim 11, wherein:
according to differences between image data values of a block within the current image and OD data values of a corresponding block within the next image, the OD strength depressing circuit determines OD shifts between the block and the corresponding block, respectively; and
the OD strength depressing circuit determines depressed OD shifts between the block and the corresponding block through multiplying the OD shifts by an OD depressed gain corresponding to the block, respectively;
wherein:
when an image data value of a sub-pixel of the block is less than an OD data value of a corresponding sub-pixel of the corresponding block, a depressed OD data value of the corresponding sub-pixel equals the image data value of the sub-pixel plus a corresponding depressed OD shift; and
when the image data value of the sub-pixel of the block is greater than the OD data value of the corresponding sub-pixel of the corresponding block, the depressed OD data value of the corresponding sub-pixel equals the image data value of the sub-pixel minus the corresponding depressed OD shift.

### Claim 20 (depends on 19)

The apparatus of claim 19, wherein the OD strength depressing circuit further comprises a protection circuit, wherein:
when the image data value of the sub-pixel is less than the OD data value and the depressed OD data value is less than an image data value of the corresponding sub-pixel, the protection circuit replaces the depressed OD data value with a new OD value that is equal to the image data value of the corresponding sub-pixel; and
when the image data value of the sub-pixel is greater than the OD data value and the depressed OD data value is greater than the image data value of the corresponding sub-pixel, the protection circuit replaces the depressed OD data value with a new OD value that is equal to the image data value of the corresponding sub-pixel.