JP2009124585A5

JP2009124585A5 -

Info

Publication number: JP2009124585A5
Application number: JP2007298341A
Authority: JP
Filing date: 2007-11-16
Publication date: 2011-01-06
Anticipated expiration: 2027-11-16

Claims

An image encoding apparatus that decomposes image data composed of a luminance component and a color difference component into blocks each composed of a plurality of pixels, and performs an encoding process in units of the blocks,
Range detection means for detecting whether the value of the luminance component in the block unit is outside a predetermined range;
If the value of the luminance component in the block unit is outside the predetermined range as a result of detection by the range detection means, the code amount is the smallest for the color difference component in the block unit regardless of the component. An image encoding apparatus comprising: code assigning means for assigning codes.

The outside of the predetermined range is when the value of the luminance component is smaller than the first threshold value specified for the value of the luminance component, or the second threshold value larger than the first threshold value. The image coding apparatus according to claim 1, wherein the value of the luminance component is large.

Encoding means for performing encoding by encoding the value of the luminance component in the block unit;
Decoding means for decoding the value of the luminance component in the block unit encoded by the encoding means,
2. The range detecting unit detects whether or not the value of a luminance component decoded by the decoding unit after being encoded by the encoding unit is outside a predetermined range. The image encoding device described in 1.

When the value of the luminance component within the block unit is outside the predetermined range, and when the block outside the predetermined range is intra-processed, the DC component is equal to the DC prediction value, and the AC components are all 0. Encoded as
When the block is inter-processed, it has coding means for coding a bit string indicating the presence / absence of a code for each block in a state where there is no code for a bit indicating the presence / absence of a code of a color difference component The image encoding device according to claim 1.

If the value of the luminance component within the block unit of the luminance component of the input image data is outside the predetermined range as a result of detection by the range detection means, the code difference is replaced with the color difference component within the block unit. 5. The image coding apparatus according to claim 1, further comprising a color difference component replacement unit that replaces the data with the least generated data.

The chrominance component replacement means replaces all the values of the chrominance components in the block with a DC prediction value when the block outside the predetermined range is subjected to intra processing, and when the block is subjected to inter processing. 6. The image coding apparatus according to claim 5, wherein the color difference component in the block is replaced with the color difference component of the inter prediction destination.

An image encoding apparatus that decomposes image data composed of a luminance component and a color difference component into blocks each composed of a plurality of pixels, and performs an encoding process in units of the blocks,
Encoding means for performing encoding by encoding the value of the luminance component in the block unit;
Decoding means for decoding a value of a luminance component in a block unit encoded by the encoding means;
Filter processing means for performing filter processing on the value of the luminance component decoded by the decoding means;
Range detection means for detecting whether the value of the luminance component filtered by the filter processing means is outside a predetermined range;
If the value of the luminance component in the block unit is outside the predetermined range as a result of detection by the range detection means, the code amount is the smallest for the color difference component in the block unit regardless of the component. An image encoding apparatus comprising: code assigning means for assigning codes.

The encoding means, when the value of the luminance component in the block unit is outside a predetermined range, for the bit string indicating the presence / absence of the code of the block unit, the bit indicating the presence / absence of the code of the color difference component is unsigned 8. The image encoding apparatus according to claim 7, wherein a code assigned to the color difference component in the block unit is encoded as a state.

An image encoding apparatus that decomposes image data composed of a luminance component and a color difference component into blocks each composed of a plurality of pixels, and performs an encoding process on each block,
Range detection means for detecting whether the value of the luminance component in the block unit is outside a predetermined range;
As a result of the detection by the range detection means, if the value of the luminance component within the block unit is outside the predetermined range, and if the block outside the predetermined range is subjected to intra processing, the block is predicted in a specific prediction mode. If all the values of the color difference components in the block are replaced with the prediction values of the prediction mode, and the block is inter-processed, the color difference components in the block are replaced with the color difference components of the inter prediction destination An image coding apparatus comprising: a color difference component replacement unit.

An image encoding method in which image data composed of a luminance component and a color difference component is decomposed into blocks each composed of a plurality of pixels, and an encoding process is performed for each block.
A range detection step of detecting whether the value of the luminance component in the block unit is outside a predetermined range;
If the value of the luminance component in the block unit is outside the predetermined range as a result of detection in the range detection step, the code amount is the smallest for the color difference component in the block unit regardless of the component. And a code assigning step for assigning a code.

An image encoding method in which image data composed of a luminance component and a color difference component is decomposed into blocks each composed of a plurality of pixels, and an encoding process is performed for each block.
An encoding step of encoding by performing a quantization process on the value of the luminance component in the block unit;
A decoding step of decoding the value of the luminance component in the block unit encoded in the encoding step;
A filtering process for performing a filtering process on the value of the luminance component decoded in the decoding process;
A range detection step for detecting whether or not the luminance component value filtered in the filtering step is outside a predetermined range;
If the value of the luminance component in the block unit is outside the predetermined range as a result of detection in the range detection step, the code amount is the smallest for the color difference component in the block unit regardless of the component. And a code assigning step for assigning a code.

An image encoding method in which image data composed of a luminance component and a color difference component is decomposed into blocks each composed of a plurality of pixels, and an encoding process is performed for each block.
A range detection step of detecting whether the value of the luminance component in the block unit is outside a predetermined range;
As a result of detection in the range detection step, when the value of the luminance component within the block unit is out of the predetermined range, or when the block outside the predetermined range is subjected to intra processing, the block is predicted in a specific prediction mode. And replace all the values of the color difference components in the block with the prediction values of the prediction mode, and when the block is inter-processed, replace the color difference components in the block with the color difference components of the inter prediction destination And a color difference component replacement step.