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US 9,071,836 B2Granted
Image processing apparatus and image processing method
AssigneeFujitsu Limited
InventorAkira Nakagawa
Life of this patent
Estimating the term…
Abstract
An image processing apparatus includes a predictive picture generator configured to generate a predictive picture for an encoding target block based on pixel values of pixels included in already-encoded blocks around the encoding target block, a predictive error generator configured to generate predictive error based on a picture expressed by the encoding target block and a weighting unit configured to apply weights to pixel values by conducting a multiplication that multiplies by a constant greater than 1 the pixel values of pixels used to generate a predictive picture for another encoding target block, the pixels being pixels from among a plurality of pixels included in predictive error generated by the predictive error generator.
Claims18
An image processing apparatus comprising:
- a processor;
- and
- a memory which stores a plurality of instructions, which when executed by the processor, cause the processor to execute;
- generating a predictive picture for an encoding target block based on pixel values of pixels included in already-encoded blocks around the encoding target block;
- generating predictive error based on a picture expressed by the encoding target block and the predictive picture;
- applying weights to pixel values by conducting one or both of a first multiplication that multiplies by a first constant greater than 1 the pixel values of pixels used to generate a predictive picture for another encoding target block, and a second multiplication that multiplies by a second constant less than 1 the pixel values of pixels not used to generate the predictive picture for another encoding target block, the pixels being pixels from among a plurality of pixels included in the predictive error;
- generating transform coefficients by applying an orthogonal transform to the predictive error;
- generating quantization coefficients by quantizing the transform coefficients;
- generating reverse quantization coefficients by reverse quantizing the quantization coefficients;
- generating inverse orthogonal transform data by applying an inverse orthogonal transform to the reverse quantization coefficients;
- reconstructing the predictive error by conducting one or both of a first division that divides by a third constant greater than 1 the pixel values of pixels used to generate the predictive picture for another encoding target block, and a second division that multiplies by a fourth constant less than 1 the pixel values of pixels not used to generate the predictive picture for another encoding target block, the pixels being pixels from among a plurality of pixels included in the inverse orthogonal transform data;
- generating a decoded picture based on the reconstructed predictive error and the predictive picture;
- and
- changing the value of the first constant for each pixel according to the usage frequency of pixels used to generate the predictive picture for another encoding target block from among a plurality of pixels included in the predictive error,
- wherein a frequency with which pixels at the lower right of the encoding target block are used is higher than a frequency with which pixels lining a right edge or pixels lining a bottom edge are used.
12 more elements
An image processing apparatus comprising:
- a processor;
- and
- a memory which stores a plurality of instructions, which when executed by the processor, cause the processor to execute;
- generating a predictive picture for a decoding target block based on pixel values of pixels included in already-decoded blocks around the decoding target block;
- generating reverse quantization coefficients by reverse quantizing quantization coefficients included in encoded data;
- generating generate inverse orthogonal transform data by applying an inverse orthogonal transform to the reverse quantization coefficients;
- reconstructing predictive error from when the encoded data was generated by conducting one or both of a first division that divides by a fifth constant greater than 1 the pixel values of pixels used to generate a predictive picture for another decoding target block, and a second division that divides by a sixth constant less than 1 the pixel values of pixels not used to generate a predictive picture for another decoding target block, the pixels being pixels from among a plurality of pixels included in the inverse orthogonal transform data;
- and
- generating a decoded picture based on the reconstructed predictive error and the predictive picture,
- wherein a frequency with which pixels at the lower right of the decoding target block are used is higher than a frequency with which pixels lining a right edge or pixels lining a bottom edge are used.
7 more elements
An image processing method comprising:
- generating a predictive picture for an encoding target block based on pixel values of pixels included in already-encoded blocks around the encoding target block;
- generating predictive error based on a picture in the encoding target block and a predictive picture generated by the predictive picture generating operation;
- applying weights to pixel values by conducting one or both of a first multiplication that multiplies by a first constant greater than 1 the pixel values of pixels used to generate a predictive picture for another encoding target block, and a second multiplication that multiplies by a second constant less than 1 the pixel values of pixels not used to generate a predictive picture for another encoding target block, the pixels being pixels from among a plurality of pixels included in predictive error generated by the predictive error generating operation;
- generating transform coefficients by applying an orthogonal transform to predictive error that has been multiplied by the weighting operation;
- generating quantization coefficients by quantizing transform coefficients generated by the orthogonal transform applying operation;
- generating reverse quantization coefficients by reverse quantizing quantization coefficients generated by the quantizing operation;
- generating inverse orthogonal transform data by applying an inverse orthogonal transform to reverse quantization coefficients generated by the reverse quantizing operation;
- reconstructing predictive error by conducting one or both of a first division that divides by a third constant greater than 1 the pixel values of pixels used to generate a predictive picture for another encoding target block, and a second division that multiplies by a fourth constant less than 1 the pixel values of pixels not used to generate a predictive picture for another encoding target block, the pixels being pixels from among a plurality of pixels included in inverse orthogonal transform data generated by the inverse orthogonal transform applying operation;
- and
- generating a decoded picture based on predictive error reconstructed by the predictive error reconstructing operation and a predictive picture generated by the predictive picture generating operation,
- wherein, in the weighting operation, the value of the first constant is changed for each pixel according to the usage frequency of pixels used to generate a predictive picture for another encoding target block from among a plurality of pixels included in predictive error generated by the predictive error generating operation,
- wherein a frequency with which pixels at the lower right of the encoding target block are used is higher than a frequency with which pixels lining a right edge or pixels lining a bottom edge are used.
9 more elements
An image processing method comprising:
- generating a predictive picture for a decoding target block based on pixel values of pixels included in already-decoded blocks around the decoding target block;
- generating reverse quantization coefficients by reverse quantizing quantization coefficients included in encoded data;
- generating inverse orthogonal transform data by applying an inverse orthogonal transform to reverse quantization coefficients generated by the reverse quantizing operation;
- reconstructing predictive error from when the encoded data was generated by conducting one or both of a first division that divides by a fifth constant greater than 1 the pixel values of pixels used to generate a predictive picture for another decoding target block, and a second division that divides by a sixth constant less than 1 the pixel values of pixels not used to generate a predictive picture for another decoding target block, the pixels being pixels from among a plurality of pixels included in inverse orthogonal transform data generated by the inverse orthogonal transform applying operation;
- and
- a decoded picture generator configured to generate a decoded picture based on predictive error reconstructed by the predictive error reconstructing operation and a predictive picture generated by the predictive picture generating operation,
- wherein a frequency with which pixels at the lower right of the decoding target block are used is higher than a frequency with which pixels lining a right edge or pixels lining a bottom edge are used.
4 more elements
An image processing apparatus comprising:
- a processor;
- and
- a memory which stores a plurality of instructions, which when executed by the processor, cause the processor to execute;
- generating a predictive picture for an encoding target block based on pixel values of pixels included in already-encoded blocks around the encoding target block;
- generating predictive error based on a picture expressed by the encoding target block and the predictive picture;
- and
- applying weights to pixel values by conducting a multiplication that multiplies by a constant greater than 1 the pixel values of pixels used to generate a predictive picture for another encoding target block, the pixels being pixels from among a plurality of pixels included in the predictive error,
- wherein a frequency with which pixels at the lower right of the encoding target block are used is higher than a frequency with which pixels lining a right edge or pixels lining a bottom edge are used.
5 more elements
An image processing apparatus comprising:
- a processor;
- and
- a memory which stores a plurality of instructions, which when executed by the processor, cause the processor to execute;
- generating a predictive picture for an encoding target block based on pixel values of pixels included in already-encoded blocks around the encoding target block;
- generating predictive error based on a picture expressed by the encoding target block and the predictive picture;
- and
- applying weights to pixel values by conducting a multiplication that multiplies by a constant less than 1 the pixel values of pixels not used to generate a predictive picture for another encoding target block, the pixels being pixels from among a plurality of pixels included in predictive error generated by the predictive error generator.
4 more elements
Dependencies are inferred from the claim text.