CN-121986474-A - Cross-component scaling factor in BIF

Abstract

Systems, methods, and tools can be configured for a bi-component scaling factor for bilateral filtering (BIF). An apparatus (e.g., a video decoder) is capable of obtaining filtered chroma samples by applying a bilateral filter to the chroma samples. The apparatus is capable of determining a chroma sample scaling factor for the chroma sample based on a luma transform unit associated with a luma sample. The apparatus is capable of obtaining scaled filtered chroma samples based on the determined chroma sample scaling factor. The apparatus is capable of decoding a video block associated with the chroma samples based on the scaled filtered chroma samples. The chroma sample scaling factor can be determined based on one or more of a size of a chroma transform block, a difference in chroma sample values in the video block, or a variance of chroma samples within the video block. Determining the chroma sample scaling factor can include referencing a look-up table (LUT) based on an average difference (MAD) of luma sample values in the luma transform unit.

Inventors

• F. Lefebvre
• G. Poisson
• P. Borders
• F. Garr Ping
• CHEN YA
• Milos Radosavlevich

Assignees

• 交互数字CE专利控股有限公司

Dates

Publication Date

20260505

Application Date

20241001

Priority Date

20231002

Claims (20)

1. 1. A video decoding apparatus, the video decoding apparatus comprising: the processor may be configured to perform the steps of, the processor is configured to: obtaining filtered chroma samples by applying a bilateral filter to the chroma samples; Determining a first chroma sample scaling factor for the chroma sample based on a luma transform unit associated with a luma sample; Determining a second chroma sample scaling factor for a chroma sample based on a chroma transform unit associated with the chroma sample; Obtaining scaled filtered chroma samples based on the determined first chroma sample scaling factor and the determined second chroma sample scaling factor, and A video block associated with the chroma samples is decoded based on the scaled filtered chroma samples.
2. 2. The device of claim 1, wherein the processor is further configured to: An average absolute difference of luminance samples associated with the luminance transformation unit is determined, wherein the first chromium sample scaling factor is also determined based on the average absolute difference of luminance samples associated with the luminance transformation unit.
3. 3. The device of any of claims 1 or 2, wherein the processor is further configured to: An average absolute difference of chroma samples associated with the chroma transform unit is determined, wherein the second chroma sample scaling factor is also determined based on the average absolute difference of chromium samples associated with the chromium transform unit.
4. 4. The device of any of claims 1-3, wherein the processor is further configured to: a scaling factor is determined based on a shape size of the chroma transform unit, wherein the first chroma sample scaling factor is also determined based on the scaling factor.
5. 5. The device of any of claims 1-4, wherein the processor is further configured to: The first and second chroma sample scaling factors are combined using a first and second scaling factor, wherein the scaled filter chroma sample is further obtained based on combining the first and second chroma sample scaling factors.
6. 6. The apparatus of claim 5, wherein the first scale factor weights the first chroma sample scaling factor, and wherein the second scale factor weights the second chroma sample scaling factor.
7. 7. The device of claim 1, wherein the processor is further configured to: an indication is received indicating that the second chroma sample scaling factor is determined to be enabled, wherein the second chroma sample scaling factor is determined based on the indication.
8. 8. An apparatus for video encoding, the apparatus comprising: the processor may be configured to perform the steps of, the processor is configured to: obtaining filtered chroma samples by applying a bilateral filter to the chroma samples; Determining a first chroma sample scaling factor for the chroma sample based on a luma transform unit associated with a luma sample; Determining a second chroma sample scaling factor for a chroma sample based on a chroma transform unit associated with the chroma sample; Obtaining scaled filtered chroma samples based on the determined first chroma sample scaling factor and the determined second chroma sample scaling factor, and Video blocks associated with the chroma samples are encoded based on the scaled filtered chroma samples.
9. 9. The device of claim 8, wherein the processor is further configured to: An average absolute difference of luminance samples associated with the luminance transformation unit is determined, wherein the first chromium sample scaling factor is also determined based on the average absolute difference of luminance samples associated with the luminance transformation unit.
10. 10. The device of any of claims 8 or 9, wherein the processor is further configured to: An average absolute difference of chroma samples associated with the chroma transform unit is determined, wherein the second chroma sample scaling factor is also determined based on the average absolute difference of chromium samples associated with the chromium transform unit.
11. 11. The device of any of claims 8 to 10, wherein the processor is further configured to: a scaling factor is determined based on a shape size of the chroma transform unit, wherein the first chroma sample scaling factor is also determined based on the scaling factor.
12. 12. The device of any of claims 8 to 11, wherein the processor is further configured to: The first and second chroma sample scaling factors are combined using a first and second scaling factor, wherein the scaled filter chroma sample is further obtained based on combining the first and second chroma sample scaling factors.
13. 13. The apparatus of claim 12, wherein the first scale factor weights the first chroma sample scaling factor, and wherein the second scale factor weights the second chroma sample scaling factor.
14. 14. The device of claim 8, wherein the processor is further configured to: including an indication indicating that the second chroma sample scaling factor is determined to be enabled, and The video block associated with the chroma samples is also encoded based on the indication.
15. 15. The apparatus of any one of claims 1 to 14, further comprising a memory operatively connected to the processor.
16. 16. A method for a video decoder, the method comprising: obtaining filtered chroma samples by applying a bilateral filter to the chroma samples; Determining a first chroma sample scaling factor for the chroma sample based on a luma transform unit associated with a luma sample; Determining a second chroma sample scaling factor for a chroma sample based on a chroma transform unit associated with the chroma sample; Obtaining scaled filtered chroma samples based on the determined first chroma sample scaling factor and the determined second chroma sample scaling factor, and A video block associated with the chroma samples is decoded based on the scaled filtered chroma samples.
17. 17. The method of claim 16, wherein the method further comprises: An average absolute difference of luminance samples associated with the luminance transformation unit is determined, wherein the first chromium sample scaling factor is also determined based on the average absolute difference of luminance samples associated with the luminance transformation unit.
18. 18. The method of any one of claims 16 or 17, wherein the method further comprises: An average absolute difference of chroma samples associated with the chroma transform unit is determined, wherein the second chroma sample scaling factor is also determined based on the average absolute difference of chromium samples associated with the chromium transform unit.
19. 19. The method of any of claims 16 to 18, wherein the method further comprises: a scaling factor is determined based on a shape size of the chroma transform unit, wherein the first chroma sample scaling factor is also determined based on the scaling factor.
20. 20. The method of any one of claims 16 to 19, wherein the method further comprises: The first and second chroma sample scaling factors are combined using a first and second scaling factor, wherein the scaled filter chroma sample is further obtained based on combining the first and second chroma sample scaling factors.

Description

Cross-component scaling factor in BIF Cross Reference to Related Applications The present application claims the benefit of EP provisional patent application number 23306685.1 filed at month 2 of 2023, the disclosure of which is incorporated herein by reference in its entirety. Background Video coding systems may be used to compress digital video signals, for example, to reduce the storage and/or transmission bandwidth required for such signals. Video coding systems may include, for example, block-based, wavelet-based, and/or object-based systems. Disclosure of Invention Systems, methods, and tools are configured for a bi-component scaling factor for bilateral filtering (BIF). A video processing device (e.g., and encoding and/or decoding device) may include a processor configured to obtain filtered chroma samples by applying a bilateral filter to the chroma samples. The apparatus is capable of determining a first chroma sample scaling factor for a chroma sample based on a luma transform unit associated with the luma sample. The apparatus is capable of determining a second chroma sample scaling factor for the chroma samples based on a chroma transform unit associated with the chroma samples. The device may obtain scaled filtered chroma samples based on the determined first chroma sample scaling factor and the determined second chroma sample scaling factor. The device may process (e.g., encode and/or decode) video blocks associated with the chroma samples based on the scaled filtered chroma samples. The device may determine an average absolute difference of luminance samples associated with the luminance transformation unit. The first chroma sample scaling factor may be determined further based on an average absolute difference of luma samples associated with the luma transform unit. The device may determine an average absolute difference of chroma samples associated with the chroma transform unit. The second chroma sample scaling factor may be determined further based on an average absolute difference of chroma samples associated with the chroma transform unit. The device may determine the scaling factor based on a shape size of the chroma transform unit. The first chroma sample scaling factor may also be determined based on the scaling factor. The apparatus may combine the first chroma sample scaling factor and the second chroma sample scaling factor using the first scaling factor and the second scaling factor. The scaled filter chroma samples may be further obtained based on combining the first chroma sample scaling factor and the second chroma sample scaling factor. The first scale factor may weight the first chroma sample scaling factor. The second scaling factor may weight the second chroma sample scaling factor. The device may receive an indication indicating that the second chroma sample scaling factor is determined to be enabled. A second chroma sample scaling factor may be determined based on the indication. Systems, methods, and tools may be configured for a bi-component scaling factor for bilateral filtering (BIF). An apparatus (e.g., a video decoder) may obtain filtered chroma samples by applying a bilateral filter to the chroma samples. The device may determine a chroma sample scaling factor for the chroma sample based on a luma transform unit associated with the luma sample. The device may obtain scaled filtered chroma samples based on the determined chroma sample scaling factor. The device may decode a video block associated with the chroma samples based on the scaled filtered chroma samples. The chroma sample scaling factor may be determined based on one or more of a size of the chroma transform block, a difference in chroma sample values in the video block, or a variance of chroma samples within the video block. Determining the chroma sample scaling factor may include referencing a look-up table (LUT) based on an average difference (MAD) of luminance sample values in the luminance transformation unit. Systems, methods, and tools may be configured for a bi-component scaling factor for bilateral filtering (BIF). An apparatus (e.g., a video encoder) may obtain filtered chroma samples by applying a bilateral filter to the chroma samples. The device may determine a chroma sample scaling factor for the chroma sample based on a luma transform unit associated with the luma sample. The device may obtain scaled filtered chroma samples based on the determined chroma sample scaling factor. The device may encode a video block associated with the chroma samples based on the scaled filtered chroma samples. The chroma sample scaling factor may be determined based on one or more of a size of the chroma transform block, a difference in chroma sample values in the video block, or a variance of chroma samples within the video block. Determining the chroma sample scaling factor may include referencing a look-up table (LUT) based on an average difference (MAD) of luminance sample values in the luminance transform