Data encoding and decoding
A video coding or decoding method using inter-image prediction to encode input video data in which each chrominance component has 1/Mth of the horizontal resolution and 1/Nth of the vertical resolution of the luminance component, where M and N are integers equal to 1 or more, including storing one or more images preceding a current image, interpolating a higher resolution version of prediction units of the stored images so that the luminance component has a horizontal resolution P times that of the corresponding portion of the stored image and a vertical resolution Q times that of the corresponding portion of the stored image, detecting inter-image motion between a current image and the one or more interpolated stored images so as to generate motion vectors between a prediction unit of the current image and areas of the one or more preceding images, and generating a motion compensated prediction.
1. A video decoding apparatus comprising:
circuitry configured to:
perform with respect to video blocks of spatial frequency data, frequency transformation by applying a frequency transformation to generate blocks of video data samples which are each scaled, and
dequantize by selecting an index value in a table in which for an index value an index scale value is provided,
wherein the index value is selected by performing, by the circuitry, a modulo 6 operation on a quantization parameter, and
wherein the index scale values in the table include values 40, 45, 51, 57, 64 and 72.
2. The video decoding apparatus according to claim 1 , wherein at least some of the values in the table are used for a video block which are not a power of 4 in size.
3. The video decoding apparatus according to claim 1 , wherein the values are quantization step sizes.
4. The video decoding apparatus according to claim 1 , wherein the index value is selected based on whether or not a video block is, or is not, a power of 4 in size and based on the quantization parameter.
5. A video receiver comprising the video decoding apparatus as claimed in claim 1 .
6. A video capture device comprising a video encoding apparatus and the video decoding apparatus as claimed in claim 1 .
7. A video decoding apparatus comprising:
circuitry configured to
perform, with respect to video blocks of spatial frequency data, frequency transformation by applying a frequency transformation to generate blocks of video data samples which are each scaled, and
dequantize by selecting an index value in a table of six values in which, for an index value, a corresponding index scale is provided,
wherein the index value is selected by performing, by the circuitry, a modulo 6 operation on a quantization parameter, and
wherein at least some of the values in the table are used for coefficients of a video block which are not a power of 4 in size.
8. The video decoding apparatus as claimed in claim 7 , wherein the index scale values in the table include the values 57, 64, and 72.
9. The video decoding apparatus as claimed in claim 8 , wherein the index scale values in the table further include the values 40, 45, and 51.
10. The video decoding apparatus as claimed in claim 7 , wherein the table is stored in a non-transitory storage medium.
11. A video receiver comprising the video decoding apparatus as claimed in claim 7 .
12. A video capture device comprising a video encoding apparatus and the video decoding apparatus as claimed in claim 7 .
13. A video decoding method comprising:
performing, with respect to video blocks of spatial frequency data, frequency transformation by applying a frequency transformation to generate blocks of video data samples which are each scaled;
dequantizing by selecting an index value in a table in which, for an index value, an index scale value is provided; and
selecting the index value by performing via circuitry a modulo 6 operation on a quantization parameter,
wherein the index scale values in the table include values 40, 45, 51, 57, 64 and 72.
14. The video decoding method according to claim 13 , wherein the values are quantization step sizes.
15. The video decoding method according to claim 13 , further comprising:
selecting the index value based on whether or not a video block is, or is not, a power of 4 in size and based on the quantization parameter.
16. A non transitory storage medium comprising executable code components which when executed on a computer cause the computer to perform the method of claim 13 .
17. A video decoding method comprising:
performing, with respect to video blocks of spatial frequency data, frequency transformation by applying a frequency transformation to generate blocks of video data samples which are each scaled;
dequantizing by selecting an index value in a table of six values in which, for an index value, a corresponding index scale is provided; and
selecting the index value by performing via circuitry a modulo 6 operation on a quantization parameter,
wherein at least some of the values in the table are used for coefficients of a video block in which are not a power of 4 in size.
18. The video decoding method as claimed in claim 17 , wherein the index scale values in the table include the values 57, 64 and 72.
19. The video decoding method as claimed in claim 18 , wherein the index scale values in the table further include the values 40, 45, and 51.
20. A non-transitory storage medium comprising executable code components which when executed on a computer cause the computer perform the method according to claim 18 .