Reduce encoder code block memory usage for non 64x64 code block sizes

[gcode-importer]

Originally reported on Google Code with ID 444

Currently, all encoder code blocks allocate 8192*2 bytes, which is equivalent to 64
x 64 x sizeof(OPJ_UINT32)  bytes. i.e. it covers the worst case scenario (no compression)
on a 64x64 size code block.

For DCP encoding, for example, which mandates 32x32 code blocks, this uses 4 times
the worst-case memory needed.  

I have attached a simple fix: use the code block dimensions to decide
how much memory to allocate. 

Reported by boxerab on 2014-11-26 04:09:17

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- _Attachment: [reduce_encode_codeblock_memory.diff](https://storage.googleapis.com/google-code-attachments/openjpeg/issue-444/comment-0/reduce_encode_codeblock_memory.diff)_

[gcode-importer]

For this fix, it may be good to add some sanity checks on the code block dimensions.
I have not done so in this patch.

Reported by boxerab on 2014-11-30 01:40:53

[gcode-importer]

Aaron,

I think that sanity checks shall be implemented. However, given that this is a coder
patch, they should probably be elsewhere (like parameter validation). This might (should)
already be the case.

Your patch does not take into account different sizes of block per tile/component &
I'll add that.

Reported by mayeut on 2014-12-12 20:43:48

• Status changed: Started

[gcode-importer]

On ElephantDream_4K.tif from the test suite encoded to j2k with -cinema4k option,

Before patch
Bytes Used  Count  Name
 696.65 MB  99.9%  main
 544.94 MB  78.2%    opj_j2k_encode
 542.39 MB  77.8%      opj_tcd_init_tile
 412.33 MB  59.1%        malloc
 128.32 MB  18.4%        calloc
   1.73 MB   0.2%        opj_tgt_create
   2.56 MB   0.3%      opj_j2k_post_write_tile
 101.33 MB  14.5%    tiftoimage
  49.36 MB   7.0%    opj_j2k_start_compress
   1.00 MB   0.1%    opj_stream_create_file_stream
   9.62 KB   0.0%    opj_setup_encoder
   1.62 KB   0.0%    opj_create_compress

After patch
Bytes Used  Count  Name
 387.31 MB  99.9%  main
 235.60 MB  60.8%    opj_j2k_encode
 233.05 MB  60.1%      opj_tcd_init_tile
 128.32 MB  33.1%        calloc
 102.99 MB  26.5%        malloc
   1.73 MB   0.4%        opj_tgt_create
   2.56 MB   0.6%      opj_j2k_post_write_tile
 101.33 MB  26.1%    tiftoimage
  49.36 MB  12.7%    opj_j2k_start_compress
   1.00 MB   0.2%    opj_stream_create_file_stream
   9.62 KB   0.0%    opj_setup_encoder
   1.62 KB   0.0%    opj_create_compress

Reported by mayeut on 2014-12-12 21:09:33

[gcode-importer]

This issue was closed by revision r2955.

Reported by mayeut on 2014-12-12 21:54:25

• Status changed: Fixed