Image compression coding apparatus and control method therefor

An image compression coding apparatus comprising:

• block formation means for dividing input image data into blocks each having a predetermined size;
• compression coding means for compression-coding the image data for each divided block using a plurality of compression coding parameters and outputting a plurality of coded data;
• coded data amount accumulation means for calculating cumulative data amounts of the plurality of coded data for the respective compression-coded blocks;
• upper limit setting means for setting a total coded data amount upper limit for input image data;
• threshold calculation means for sequentially calculating a threshold not more than the upper limit on the basis of the upper limit, a minimum coded data amount per a predetermined number of blocks, and the number of compression-coded blocks;
• and
• control means for, when the cumulative data amount exceeds the threshold, aborting compression coding processing with a corresponding compression coding parameter.

An image compression coding apparatus comprising:

• block formation means for dividing input image data into blocks each having a predetermined size;
• compression coding means for compression-coding the image data for each divided block using a plurality of compression coding parameters and outputting a plurality of coded data;
• re-compression coding means for re-compression-coding the coded data;
• coded data amount accumulation means for calculating cumulative data amounts of the plurality of coded data for the respective compression-coded blocks;
• upper limit setting means for setting a total coded data amount upper limit for input image data;
• minimum total coded data amount prediction means for calculating minimum total coded data amount predictive values of the plurality of coded data, which are to be obtained when the image data is completely compression-coded, on the basis of a minimum coded data amount per a predetermined number of blocks and the cumulative data amounts;
• and
• control means for, when the minimum total coded data amount predictive value and the sum of the cumulative data amounts exceed the upper limit, changing the compression coding parameter used by said compression coding means and causing said re-compression coding means to perform re-compression coding.

An image compression coding apparatus comprising:

• block formation means for dividing input image data into blocks each having a predetermined size;
• compression coding means for compression-coding the image data for each divided block using a plurality of compression coding parameters and outputting a plurality of coded data;
• re-compression coding means for re-compression-coding the coded data;
• coded data amount accumulation means for calculating a cumulative data amount of the coded data for a compression-coded block;
• upper limit setting means for setting a total coded data amount upper limit for input image data;
• threshold calculation means for sequentially calculating a threshold not more than the upper limit on the basis of the upper limit, a minimum coded data amount per a predetermined number of blocks, and the number of compression-coded blocks;
• and
• control means for, when the cumulative data amount exceeds the threshold, changing the compression coding parameter used by said compression coding means and causing said re-compression coding means to perform re-compression coding.

An image compression coding apparatus comprising:

• block formation means for dividing input image data into blocks each having a predetermined size;
• compression coding means for compression-coding the image data for each divided block using a plurality of compression coding parameters and outputting a plurality of coded data;
• coded data amount accumulation means for calculating cumulative data amounts of the plurality of coded data for the respective compression-coded blocks;
• upper limit setting means for setting a total coded data amount upper limit for input image data;
• maximum total coded data amount prediction means for calculating maximum total coded data amount predictive values of the plurality of coded data, which are to be obtained when the image data is completely compression-coded, on the basis of a maximum coded data amount per a predetermined number of blocks and the cumulative data amounts;
• and
• control means for, when the cumulative data amount exceeds the upper limit, performing processing to abort compression coding processing with a corresponding compression coding parameter, and when the maximum total coded data amount predictive value does not exceed the upper limit, performing processing to abort compression coding processing with a compression coding parameter higher in compression ratio than a corresponding compression coding parameter.

An image compression coding apparatus comprising:

• block formation means for dividing input image data into blocks each having a predetermined size;
• compression coding means for generating coded data by compression-coding the image data for each divided block at a first compression ratio and a second compression ratio higher than the first compression ratio;
• coded data amount accumulation means for calculating a cumulative data amount of coded data generated at the first compression ratio for each compression-coded block;
• storage means for storing coded data generated at the second compression ratio;
• upper limit setting means for setting a total coded data amount upper limit for input image data;
• maximum total coded data amount prediction means for calculating a maximum total coded data amount predictive value of image data, which is to be obtained when non-compression-coded blocks of the image data are completely compression-coded at the second compression ratio, on the basis of a maximum coded data amount per a predetermined number of blocks and the cumulative data amount;
• re-compression coding means for re-compression-coding coded data stored in said storage means at a predetermined compression ratio;
• and
• control means for, when the cumulative data amount exceeds the upper limit and the maximum total coded data amount predictive value exceeds the upper limit, performing compression coding processing for the image data upon setting the second compression ratio to a first compression ratio and a third compression ratio higher than the second compression ratio to a second compression ratio, and causing said re-compression coding means to perform re-compression coding at the third compression ratio, and when the cumulative data amount exceeds the upper limit and the maximum total coded data amount predictive value does not exceed the upper limit, aborting compression coding processing at the first compression ratio, performing only compression coding processing at the second compression ratio, and not causing said re-compression coding means to perform re-compression coding.

An image compression coding apparatus comprising:

• block formation means for dividing input image data into blocks each having a predetermined size;
• compression coding means for compression-coding the image data for each divided block using a plurality of compression coding parameters and outputting a plurality of coded data;
• coded data amount accumulation means for calculating cumulative data amounts of the plurality of coded data for the respective compression-coded blocks;
• upper limit setting means for setting a total coded data amount upper limit for input image data;
• minimum total coded data amount prediction means for calculating minimum total coded data amount predictive values of the plurality of coded data, which are to be obtained when the image data is completely compression-coded, on the basis of a minimum coded data amount per a predetermined number of blocks and the cumulative data amounts;
• maximum total coded data amount prediction means for calculating maximum total coded data amount predictive values of the plurality of coded data, which are to be obtained when the image data is completely compression-coded, on the basis of a maximum coded data amount per a predetermined number of blocks and the cumulative data amounts;
• and
• control means for, when the minimum total coded data amount predictive value exceeds the upper limit, performing processing to abort compression coding processing with a corresponding compression coding parameter, and when the maximum total coded data amount predictive value does not exceed the upper limit, performing processing to abort compression coding processing with a compression coding parameter higher in compression ratio than a corresponding compression coding parameter.

An image compression coding apparatus comprising:

• block formation means for dividing input image data into blocks each having a predetermined size;
• compression coding means for compression-coding the image data for each divided block using a plurality of compression coding parameters and outputting a plurality of coded data;
• coded data amount accumulation means for calculating cumulative data amounts of the plurality of coded data for the respective compression-coded blocks;
• upper limit setting means for setting a total coded data amount upper limit for input image data;
• threshold calculation means for sequentially calculating a threshold not more than the upper limit on the basis of the upper limit, a minimum coded data amount per a predetermined number of blocks, and the number of compression-coded blocks;
• maximum total coded data amount prediction means for calculating maximum total coded data amount predictive values of the plurality of coded data, which are to be obtained when the image data is completely compression-coded, on the basis of a maximum coded data amount per a predetermined number of blocks and the cumulative data amounts;
• and
• control means for, when the cumulative data amount exceeds the threshold, performing processing to abort compression coding processing with a corresponding compression coding parameter, and when the maximum total coded data amount predictive value does not exceed the upper limit, performing processing to abort compression coding processing with a compression coding parameter higher in compression ratio than a corresponding compression coding parameter.

An image compression coding apparatus comprising:

• block formation means for dividing input image data into blocks each having a predetermined size;
• compression coding means for generating coded data by compression-coding the image data for each divided block at a first compression ratio and a second compression ratio higher than the first compression ratio;
• coded data amount accumulation means for calculating a cumulative data amount of coded data generated at the first compression ratio for each compression-coded block;
• storage means for storing coded data generated at the second compression ratio;
• upper limit setting means for setting a total coded data amount upper limit for input image data;
• threshold calculation means for sequentially calculating a threshold not more than the upper limit on the basis of the upper limit, a minimum coded data amount per a predetermined number of blocks, and the number of compression-coded blocks;
• maximum total coded data amount prediction means for calculating a maximum total coded data amount predictive value of image data, which is to be obtained when non-compression-coded blocks of the image data are compression-coded at the second compression ratio, on the basis of a maximum coded data amount per a predetermined number of blocks and the cumulative data amount;
• re-compression coding means for re-compression-coding coded data stored in said storage means at a predetermined compression ratio;
• and
• control means for, when the cumulative data amount exceeds the threshold and the maximum total coded data amount predictive value exceeds the upper limit, performing compression coding processing for the image data upon setting the second compression ratio to a first compression ratio and a third compression ratio higher than the second compression ratio to a second compression ratio, and causing said re-compression coding means to perform re-compression coding at the third compression ratio, and when the cumulative data amount exceeds the upper limit and the maximum total coded data amount predictive value does not exceed the upper limit, aborting compression coding processing at the first compression ratio, performing only compression coding processing at the second compression ratio, and not causing said re-compression coding means to perform re-compression coding.

A control method for an image compression coding apparatus which performs compression coding processing for input image data, comprising:

• a block formation step of dividing the image data into blocks each having a predetermined size;
• a compression coding step of compression-coding the image data for each divided block using a plurality of compression coding parameters and outputting a plurality of coded data;
• a coded data amount accumulation step of calculating cumulative data amounts of the plurality of coded data for the respective compression-coded blocks;
• an upper limit setting step of setting a total coded data amount upper limit for input image data;
• a minimum total coded data amount prediction step of calculating minimum total coded data amount predictive values of the plurality of coded data, which are to be obtained when the image data is completely compression-coded, on the basis of a minimum coded data amount per a predetermined number of blocks and the cumulative data amounts;
• and
• a control step of, when the minimum total coded data amount predictive value exceeds the upper limit, aborting compression coding processing with a corresponding compression coding parameter.

A control method for an image compression coding apparatus which performs compression coding processing for input image data, comprising:

• a block formation step of dividing the image data into blocks each having a predetermined size;
• a compression coding step of compression-coding the image data for each divided block using a plurality of compression coding parameters and outputting a plurality of coded data;
• a coded data amount accumulation step of calculating cumulative data amounts of the plurality of coded data for the respective compression-coded blocks;
• an upper limit setting step of setting a total coded data amount upper limit for input image data;
• a threshold calculation step of sequentially calculating a threshold not more than the upper limit on the basis of the upper limit, a minimum coded data amount per a predetermined number of blocks, and the number of compression-coded blocks;
• and
• a control step of, when the cumulative data amount exceeds the threshold, aborting compression coding processing with a corresponding compression coding parameter.

A control method for an image compression coding apparatus which performs compression coding processing for input image data, comprising:

• a block formation step of dividing the image data into blocks each having a predetermined size;
• a compression coding step of compression-coding the image data for each divided block using a plurality of compression coding parameters and outputting a plurality of coded data;
• a re-compression coding step of re-compression-coding the coded data;
• a coded data amount accumulation step of calculating cumulative data amounts of the plurality of coded data for the respective compression-coded blocks;
• an upper limit setting step of setting a total coded data amount upper limit for input image data;
• a minimum total coded data amount prediction step of calculating minimum total coded data amount predictive values of the plurality of coded data, which are to be obtained when the image data is completely compression-coded, on the basis of a minimum coded data amount per a predetermined number of blocks and the cumulative data amounts;
• and
• a control step of, when the minimum total coded data amount predictive value and the sum of the cumulative data amounts exceed the upper limit, changing the compression coding parameter used in the compression coding step and performing re-compression coding in the re-compression coding step.

A control method for an image compression coding apparatus which performs compression coding processing for input image data, comprising:

• a block formation step of dividing the image data into blocks each having a predetermined size;
• a compression coding step of compression-coding the image data for each divided block using a plurality of compression coding parameters and outputting a plurality of coded data;
• a re-compression coding step of re-compression-coding the coded data;
• a coded data amount accumulation step of calculating a cumulative data amount of the coded data for a compression-coded block;
• an upper limit setting step of setting a total coded data amount upper limit for input image data;
• a threshold calculation step of sequentially calculating a threshold not more than the upper limit on the basis of the upper limit, a minimum coded data amount per a predetermined number of blocks, and the number of compression-coded blocks;
• and
• a control step of, when the cumulative data amount exceeds the threshold, changing the compression coding parameter used in the compression coding step and performing re-compression coding in the re-compression coding step.

A control method for an image compression coding apparatus which performs compression coding processing for input image data, comprising:

• a block formation step of dividing the image data into blocks each having a predetermined size;
• a compression coding step of compression-coding the image data for each divided block using a plurality of compression coding parameters and outputting a plurality of coded data;
• a coded data amount accumulation step of calculating cumulative data amounts of the plurality of coded data for the respective compression-coded blocks;
• an upper limit setting step of setting a total coded data amount upper limit for input image data;
• a maximum total coded data amount prediction step of calculating maximum total coded data amount predictive values of the plurality of coded data, which are to be obtained when the image data is completely compression-coded, on the basis of a maximum coded data amount per a predetermined number of blocks and the cumulative data amounts;
• and
• a control step of, when the cumulative data amount exceeds the upper limit, performing processing to abort compression coding processing with a corresponding compression coding parameter, and when the maximum total coded data amount predictive value does not exceed the upper limit, performing processing to abort compression coding processing with a compression coding parameter higher in compression ratio than a corresponding compression coding parameter.

A control method for an image compression coding apparatus which performs compression coding processing for input image data, comprising:

• a block formation step of dividing input image data into blocks each having a predetermined size;
• a compression coding step of generating coded data by compression-coding the image data for each divided block at a first compression ratio and a second compression ratio higher than the first compression ratio;
• a coded data amount accumulation step of calculating a cumulative data amount of coded data generated at the first compression ratio for each compression-coded block;
• a storage step of storing coded data generated at the second compression ratio;
• an upper limit setting step of setting a total coded data amount upper limit for input image data;
• a maximum total coded data amount prediction step of calculating a maximum total coded data amount predictive value of image data, which is to be obtained when non-compression-coded blocks of the image data are compression-coded at the second compression ratio, on the basis of a maximum coded data amount per a predetermined number of blocks and the cumulative data amount;
• a re-compression coding step of re-compression-coding coded data stored in the storage step at a predetermined compression ratio;
• and
• a control step of, when the cumulative data amount exceeds the upper limit and the maximum total coded data amount predictive value exceeds the upper limit, performing compression coding processing for the image data upon setting the second compression ratio to a first compression ratio and a third compression ratio higher than the second compression ratio to a second compression ratio, and performing re-compression coding at the third compression ratio in the re-compression coding step, and when the cumulative data amount exceeds the upper limit and the maximum total coded data amount predictive value does not exceed the upper limit, aborting compression coding processing at the first compression ratio, performing only compression coding processing at the second compression ratio, and not executing of re-compression coding in the re-compression coding step.

A control method for an image compression coding apparatus which performs compression coding processing for input image data, comprising:

• block formation step of dividing the image data into blocks each having a predetermined size;
• a compression coding step of compression-coding the image data for each divided block using a plurality of compression coding parameters and outputting a plurality of coded data;
• a coded data amount accumulation step of calculating cumulative data amounts of the plurality of coded data for the respective compression-coded blocks;
• an upper limit setting step of setting a total coded data amount upper limit for input image data;
• a minimum total coded data amount prediction step of calculating minimum total coded data amount predictive values of the plurality of coded data, which are to be obtained when the image data is completely compression-coded, on the basis of a minimum coded data amount per a predetermined number of blocks and the cumulative data amounts;
• a maximum total coded data amount prediction step of calculating maximum total coded data amount predictive values of the plurality of coded data, which are to be obtained when the image data is completely compression-coded, on the basis of a maximum coded data amount per a predetermined number of blocks and the cumulative data amounts;
• and
• a control step of, when the minimum total coded data amount predictive value exceeds the upper limit, performing processing to abort compression coding processing with a corresponding compression coding parameter, and when the maximum total coded data amount predictive value does not exceed the upper limit, performing processing to abort compression coding processing with a compression coding parameter higher in compression ratio than a corresponding compression coding parameter.

A control method for an image compression coding apparatus which performs compression coding processing for input image data, comprising:

• a block formation step of dividing the image data into blocks each having a predetermined size;
• a compression coding step of compression-coding the image data for each divided block using a plurality of compression coding parameters and outputting a plurality of coded data;
• a coded data amount accumulation step of calculating cumulative data amounts of the plurality of coded data for the respective compression-coded blocks;
• an upper limit setting step of setting a total coded data amount upper limit for input image data;
• a threshold calculation step of sequentially calculating a threshold not more than the upper limit on the basis of the upper limit, a minimum coded data amount per a predetermined number of blocks, and the number of compression-coded blocks;
• a maximum total coded data amount prediction step of calculating maximum total coded data amount predictive values of the plurality of coded data, which are to be obtained when the image data is completely compression-coded, on the basis of a maximum coded data amount per a predetermined number of blocks and the cumulative data amounts;
• and
• a control step of, when the cumulative data amount exceeds the threshold, performing processing to abort compression coding processing with a corresponding compression coding parameter, and when the maximum total coded data amount predictive value does not exceed the upper limit, performing processing to abort compression coding processing with a compression coding parameter higher in compression ratio than a corresponding compression coding parameter.

A control method for an image compression coding apparatus which performs compression coding processing for input image data, comprising:

• a block formation step of dividing the image data into blocks each having a predetermined size;
• a compression coding step of generating coded data by compression-coding the image data for each divided block at a first compression ratio and a second compression ratio higher than the first compression ratio;
• a coded data amount accumulation step of calculating a cumulative data amount of coded data generated at the first compression ratio for each compression-coded block;
• a storage step of storing coded data generated at the second compression ratio;
• an upper limit setting step of setting a total coded data amount upper limit for input image data;
• a threshold calculation step of sequentially calculating a threshold not more than the upper limit on the basis of the upper limit, a minimum coded data amount per a predetermined number of blocks, and the number of compression-coded blocks;
• a maximum total coded data amount prediction step of calculating a maximum total coded data amount predictive value of image data, which is to be obtained when non-compression-coded blocks of the image data are compression-coded at the second compression ratio, on the basis of a maximum coded data amount per a predetermined number of blocks and the cumulative data amount;
• a re-compression coding step of re-compression-coding coded data stored in the storage step at a predetermined compression ratio;
• and
• a control step of, when the cumulative data amount exceeds the threshold and the maximum total coded data amount predictive value exceeds the upper limit, performing compression coding processing for the image data upon setting the second compression ratio to a first compression ratio and a third compression ratio higher than the second compression ratio to a second compression ratio, and performing re-compression coding at the third compression ratio in the re-compression coding step, and when the cumulative data amount exceeds the upper limit and the maximum total coded data amount predictive value does not exceed the upper limit, aborting compression coding processing at the first compression ratio, performing only compression coding processing at the second compression ratio, and not executing of re-compression coding in the re-compression coding step.

A computer program for controlling an image compression coding apparatus which performs compression coding processing for input image data, the program adapted to execute

• a block formation procedure of dividing the image data into blocks each having a predetermined size;
• a compression coding procedure of compression-coding the image data for each divided block using a plurality of compression coding parameters and outputting a plurality of coded data;
• a coded data amount accumulation procedure of calculating cumulative data amounts of the plurality of coded data for the respective compression-coded blocks;
• an upper limit setting procedure of setting a total coded data amount upper limit for input image data;
• a minimum total coded data amount prediction procedure of calculating minimum total coded data amount predictive values of the plurality of coded data, which are to be obtained when the image data is completely compression-coded, on the basis of a minimum coded data amount per a predetermined number of blocks and the cumulative data amounts;
• and
• a control procedure of, when the minimum total coded data amount predictive value exceeds the upper limit, aborting compression coding processing with a corresponding compression coding parameter.