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Implement arithmetic coding with 12-bit precision

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This actually works and apparently always has worked.  It only failed
because the libjpeg code, which did not originally support arithmetic
coding, assumed that optimize_coding should always be TRUE for 12-bit
data precision.
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DRC
2023-01-26 13:11:58 -06:00
parent fc01f4673b
commit 96bc40c1b3
19 changed files with 68 additions and 52 deletions
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10
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@@ -572,7 +572,7 @@ YUV Image Format Notes</h2>
</div><div class="memdoc">
<p>This option will enable arithmetic entropy coding in the JPEG image generated by this particular transform. </p>
<p>Arithmetic entropy coding will generally improve compression relative to Huffman entropy coding (the default), but it will reduce decompression performance considerably. Can be combined with <a class="el" href="group___turbo_j_p_e_g.html#gad2371c80674584ecc1a7d75e564cf026" title="This option will enable progressive entropy coding in the JPEG image generated by this particular tra...">TJXOPT_PROGRESSIVE</a>. Arithmetic entropy coding is currently only implemented for 8-bit samples. </p>
<p>Arithmetic entropy coding will generally improve compression relative to Huffman entropy coding (the default), but it will reduce decompression performance considerably. Can be combined with <a class="el" href="group___turbo_j_p_e_g.html#gad2371c80674584ecc1a7d75e564cf026" title="This option will enable progressive entropy coding in the JPEG image generated by this particular tra...">TJXOPT_PROGRESSIVE</a>. </p>
</div>
</div>
@@ -689,7 +689,7 @@ YUV Image Format Notes</h2>
</div><div class="memdoc">
<p>This option will enable progressive entropy coding in the JPEG image generated by this particular transform. </p>
<p>Progressive entropy coding will generally improve compression relative to baseline entropy coding (the default), but it will reduce decompression performance considerably. Implies <a class="el" href="group___turbo_j_p_e_g.html#ga6bedf37aa9e1122f3ec9f7302ca59117" title="This option will enable optimized baseline entropy coding in the JPEG image generated by this particu...">TJXOPT_OPTIMIZE</a>. Can be combined with <a class="el" href="group___turbo_j_p_e_g.html#gaecaaa3b7e2af812592c015d83207f010" title="This option will enable arithmetic entropy coding in the JPEG image generated by this particular tran...">TJXOPT_ARITHMETIC</a>. </p>
<p>Progressive entropy coding will generally improve compression relative to baseline entropy coding (the default), but it will reduce decompression performance considerably. Can be combined with <a class="el" href="group___turbo_j_p_e_g.html#gaecaaa3b7e2af812592c015d83207f010" title="This option will enable arithmetic entropy coding in the JPEG image generated by this particular tran...">TJXOPT_ARITHMETIC</a>. Implies <a class="el" href="group___turbo_j_p_e_g.html#ga6bedf37aa9e1122f3ec9f7302ca59117" title="This option will enable optimized baseline entropy coding in the JPEG image generated by this particu...">TJXOPT_OPTIMIZE</a> unless <a class="el" href="group___turbo_j_p_e_g.html#gaecaaa3b7e2af812592c015d83207f010" title="This option will enable arithmetic entropy coding in the JPEG image generated by this particular tran...">TJXOPT_ARITHMETIC</a> is also specified. </p>
</div>
</div>
@@ -874,7 +874,7 @@ YUV Image Format Notes</h2>
<p><b>Value</b></p><ul>
<li><code>8</code>, <code>12</code>, or <code>16</code></li>
</ul>
<p>12-bit data precision implies <a class="el" href="group___turbo_j_p_e_g.html#ggaa0f6be63ba78278299c9f5c12031fe82a8f0af9afc0b36443751f9ee82b760aa6" title="Optimized baseline entropy coding [lossy compression only].">TJPARAM_OPTIMIZE</a>. </p>
<p>12-bit data precision implies <a class="el" href="group___turbo_j_p_e_g.html#ggaa0f6be63ba78278299c9f5c12031fe82a8f0af9afc0b36443751f9ee82b760aa6" title="Optimized baseline entropy coding [lossy compression only].">TJPARAM_OPTIMIZE</a> unless <a class="el" href="group___turbo_j_p_e_g.html#ggaa0f6be63ba78278299c9f5c12031fe82a1c756757384308145602c040524aebf7" title="Arithmetic entropy coding.">TJPARAM_ARITHMETIC</a> is set. </p>
</td></tr>
<tr><td class="fieldname"><a id="ggaa0f6be63ba78278299c9f5c12031fe82a46a10d46309514907d0c39fcd86c324c"></a>TJPARAM_COLORSPACE&#160;</td><td class="fielddoc"><p>JPEG colorspace. </p>
<p>The JPEG image uses (decompression) or will use (lossy compression) the specified colorspace.</p>
@@ -912,7 +912,7 @@ YUV Image Format Notes</h2>
<li><code>0</code> <em>[default for compression, lossless transformation]</em> The lossy JPEG image uses (decompression) or will use (compression, lossless transformation) baseline entropy coding.</li>
<li><code>1</code> The lossy JPEG image uses (decompression) or will use (compression, lossless transformation) progressive entropy coding. For lossless transformation, this can also be specified using <a class="el" href="group___turbo_j_p_e_g.html#gad2371c80674584ecc1a7d75e564cf026" title="This option will enable progressive entropy coding in the JPEG image generated by this particular tra...">TJXOPT_PROGRESSIVE</a>.</li>
</ul>
<p>Progressive entropy coding will generally improve compression relative to baseline entropy coding, but it will reduce compression and decompression performance considerably. Implies <a class="el" href="group___turbo_j_p_e_g.html#ggaa0f6be63ba78278299c9f5c12031fe82a8f0af9afc0b36443751f9ee82b760aa6" title="Optimized baseline entropy coding [lossy compression only].">TJPARAM_OPTIMIZE</a>. Can be combined with <a class="el" href="group___turbo_j_p_e_g.html#ggaa0f6be63ba78278299c9f5c12031fe82a1c756757384308145602c040524aebf7" title="Arithmetic entropy coding.">TJPARAM_ARITHMETIC</a>. </p>
<p>Progressive entropy coding will generally improve compression relative to baseline entropy coding, but it will reduce compression and decompression performance considerably. Can be combined with <a class="el" href="group___turbo_j_p_e_g.html#ggaa0f6be63ba78278299c9f5c12031fe82a1c756757384308145602c040524aebf7" title="Arithmetic entropy coding.">TJPARAM_ARITHMETIC</a>. Implies <a class="el" href="group___turbo_j_p_e_g.html#ggaa0f6be63ba78278299c9f5c12031fe82a8f0af9afc0b36443751f9ee82b760aa6" title="Optimized baseline entropy coding [lossy compression only].">TJPARAM_OPTIMIZE</a> unless <a class="el" href="group___turbo_j_p_e_g.html#ggaa0f6be63ba78278299c9f5c12031fe82a1c756757384308145602c040524aebf7" title="Arithmetic entropy coding.">TJPARAM_ARITHMETIC</a> is also set. </p>
</td></tr>
<tr><td class="fieldname"><a id="ggaa0f6be63ba78278299c9f5c12031fe82ac478910e20ecf61b914f9824d80f8167"></a>TJPARAM_SCANLIMIT&#160;</td><td class="fielddoc"><p>Progressive JPEG scan limit for lossy JPEG images [decompression, lossless transformation]. </p>
<p>Setting this parameter will cause the decompression and transform functions to return an error if the number of scans in a progressive JPEG image exceeds the specified limit. The primary purpose of this is to allow security-critical applications to guard against an exploit of the progressive JPEG format described in <a href="https://libjpeg-turbo.org/pmwiki/uploads/About/TwoIssueswiththeJPEGStandard.pdf" target="_blank">this report</a>.</p>
@@ -926,7 +926,7 @@ YUV Image Format Notes</h2>
<li><code>0</code> <em>[default for compression, lossless transformation]</em> The lossy JPEG image uses (decompression) or will use (compression, lossless transformation) Huffman entropy coding.</li>
<li><code>1</code> The lossy JPEG image uses (decompression) or will use (compression, lossless transformation) arithmetic entropy coding. For lossless transformation, this can also be specified using <a class="el" href="group___turbo_j_p_e_g.html#gaecaaa3b7e2af812592c015d83207f010" title="This option will enable arithmetic entropy coding in the JPEG image generated by this particular tran...">TJXOPT_ARITHMETIC</a>.</li>
</ul>
<p>Arithmetic entropy coding will generally improve compression relative to Huffman entropy coding, but it will reduce compression and decompression performance considerably. Can be combined with <a class="el" href="group___turbo_j_p_e_g.html#ggaa0f6be63ba78278299c9f5c12031fe82a1716f242b3859905b4a317dae8cfb75f" title="Progressive entropy coding.">TJPARAM_PROGRESSIVE</a>. Arithmetic entropy coding is currently only implemented for 8-bit samples. </p>
<p>Arithmetic entropy coding will generally improve compression relative to Huffman entropy coding, but it will reduce compression and decompression performance considerably. Can be combined with <a class="el" href="group___turbo_j_p_e_g.html#ggaa0f6be63ba78278299c9f5c12031fe82a1716f242b3859905b4a317dae8cfb75f" title="Progressive entropy coding.">TJPARAM_PROGRESSIVE</a>. </p>
</td></tr>
<tr><td class="fieldname"><a id="ggaa0f6be63ba78278299c9f5c12031fe82a249f35f0770792b19f995e603bb17c6f"></a>TJPARAM_LOSSLESS&#160;</td><td class="fielddoc"><p>Lossless JPEG. </p>
<p><b>Value</b></p><ul>