Back to results
US 12,771,845 B2Granted
Video encoding and decoding using differential modulation
AssigneesHyundai Motor Company, Kia Corporation, Ewha University-Industry Collaboration Foundation
InventorsJe Won Kang, Seung Wook Park, Wha Pyeong Lim
Life of this patent
Estimating the term…
Abstract
Disclosed is a video encoding and decoding technology using a differential modulation technique for a residual signal in order to enhance compression performance in a transform skip mode. The differential modulation technique is applicable to both luma and chroma components as long as the chroma format is not monochrome (i.e. as long as chroma_format_idc=0 is not true).
Claims11
An apparatus for decoding a bitstream encoded from a video sequence comprising a plurality of pictures, the apparatus comprising at least one processor configured to:
- decode, from a sequence parameter set of the bitstream, information on a chroma sampling format and high level syntax elements related to differential modulation for residual signals,
- wherein the information on the chroma sampling format indicates one of a plurality of chroma sampling formats including 4:4:4, 4:2:2, or 4:2:0, and
- wherein the high level syntax elements comprise a single common control flag indicating whether the differential modulation is permitted for the residual signals of each of luma and chroma components of the video sequence and information on a maximum block size for which the differential modulation is permitted;
- decode a first chroma syntax element indicating whether the differential modulation has been applied to a chroma block corresponding to a first block to be currently decoded, when the first block satisfies conditions defined by the information on the chroma sampling format and the high level syntax elements;
- decode a second chroma syntax element indicating a differential modulation direction applied to the chroma block in response to the first chroma syntax element indicating that the differential modulation has been applied to the chroma block;
- determine a differential-modulated residual block for the chroma block from the bitstream;
- determine quantized residual values by differential-demodulating the differential-modulated residual block in the differential modulation direction indicated by the second chroma syntax element;
- inversely quantize the quantized residual values for the chroma block;
- generate predicted values for the chroma block;
- and
- reconstruct the chroma block corresponding to the first block based on the inversely quantized residual values and the predicted values,
- wherein the conditions defined by the information on the chroma sampling format and the high level syntax elements are satisfied when:
- (1) the single common control flag indicates that the differential modulation is permitted for the video sequence,
- (2) a value obtained by dividing a width of the first block by a horizontal scaling factor determined by the chroma sampling format that the information on the chroma sampling format indicates among the plurality of chroma sampling formats is smaller than or equal to the maximum block size, and
- (3) a value obtained by dividing a height of the first block by a vertical scaling factor determined by the chroma sampling format indicated by the information on the chroma sampling format is smaller than or equal to the maximum block size.
12 more elements
An apparatus for encoding a video sequence comprising a plurality of pictures, the apparatus comprising at least one processor configured to:
- encode, in a sequence parameter set of a bitstream, information on a chroma sampling format and high level syntax elements related to differential modulation for residual signals,
- wherein the information on the chroma sampling format indicates one of a plurality of chroma sampling formats including 4:4:4, 4:2:2, or 4:2:0, and
- wherein the high level syntax elements comprise a single common control flag indicating whether the differential modulation is permitted for the residual signals of each of luma and chroma components of the video sequence and information on a maximum block size for which the differential modulation is permitted;
- encode a first chroma syntax element indicating whether the differential modulation has been applied to a chroma block corresponding to a first block, when the first block to be currently decoded satisfies conditions defined by the information on the chroma sampling format and the high level syntax elements;
- encode a second chroma syntax element indicating a differential modulation direction applied to the chroma block in response to the first chroma syntax element indicating that the differential modulation has been applied to the chroma block;
- generate predicted values for the chroma block;
- determine a residual block for the chroma block based on the predicted values for the chroma block;
- generate quantized residual values by quantizing the residual block for the chroma block;
- determine differential-modulated residual values by differential-modulating the quantized residual values in the differential modulation direction indicated by the second chroma syntax element;
- and
- encode the differential-modulated residual values in the bitstream,
- wherein the conditions defined by the information on the chroma sampling format and the high level syntax elements are satisfied when:
- (1) the single common control flag indicates that the differential modulation is permitted for the video sequence,
- (2) a value obtained by dividing a width of the first block by a horizontal scaling factor determined by the chroma sampling format that the information on the chroma sampling format indicates among the plurality of chroma sampling formats is smaller than or equal to the maximum block size, and
- (3) a value obtained by dividing a height of the first block by a vertical scaling factor determined by the chroma sampling format indicated by the information on the chroma sampling format is smaller than or equal to the maximum block size.
12 more elements
An apparatus for providing a video decoding apparatus with a video data, the apparatus comprising at least one processor configured to:
- encode a video data into a bitstream;
- and
- transmit the bitstream to the video decoding apparatus,
- wherein the encoding of the video data includes:
- encoding, in a sequence parameter set of the bitstream, information on a chroma sampling format and high level syntax elements related to differential modulation for residual signals,
- wherein the information on the chroma sampling format indicates one of a plurality of chroma sampling formats including 4:4:4, 4:2:2, or 4:2:0, and
- wherein the high level syntax elements comprise a single common control flag indicating whether the differential modulation is permitted for the residual signals of each of luma and chroma components of the video sequence and information on a maximum block size for which the differential modulation is permitted;
- encoding a first chroma syntax element indicating whether the differential modulation has been applied to a chroma block corresponding to a first block, when the first block to be currently decoded satisfies conditions defined by the information on the chroma sampling format and the high level syntax elements;
- encoding a second chroma syntax element indicating a differential modulation direction applied to the chroma block in response to the first chroma syntax element indicating that the differential modulation has been applied to the chroma block;
- generating predicted values for the chroma block;
- determining a residual block for the chroma block based on the predicted values of the chroma block;
- generating quantized residual values by quantizing the residual block for the chroma block;
- determining differential-modulated residual values by differential-modulating the quantized residual values in the differential modulation direction indicated by the second chroma syntax element;
- and
- encoding the differential-modulated residual values in the bitstream,
- wherein the conditions defined by the information on the chroma sampling format and the high level syntax elements are satisfied when:
- (1) the single common control flag indicates that the differential modulation is permitted for the video sequence,
- (2) a value obtained by dividing a width of the first block by a horizontal scaling factor determined by the chroma sampling format that the information on the chroma sampling format indicates among the plurality of chroma sampling formats is smaller than or equal to the maximum block size, and
- (3) a value obtained by dividing a height of the first block by a vertical scaling factor determined by the chroma sampling format indicated by the information on the chroma sampling format is smaller than or equal to the maximum block size.
16 more elements
Dependencies are inferred from the claim text.