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LibGfx/TIFF: Add AdobeDeflate compression support

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This new compression is quite popular and uses a basic Zlib compression
to compress strips. Note that this is not part of the original TIFF
specification but in the Technical Notes from 2002:
https://web.archive.org/web/20160305055905/http://partners.adobe.com/public/developer/en/tiff/TIFFphotoshop.pdf

The test case was generated with GIMP.
This commit is contained in:
Lucas CHOLLET 2023-12-23 00:09:26 -05:00 • committed by Tim Schumacher
parent 9c5a75067f
commit 73c8b4865e
4 changed files with 29 additions and 0 deletions
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16
Userland/Libraries/LibGfx/ImageFormats/TIFFLoader.cpp
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@ -5,11 +5,13 @@
*/
#include "TIFFLoader.h"
#include <AK/ConstrainedStream.h>
#include <AK/Debug.h>
#include <AK/Endian.h>
#include <AK/String.h>
#include <LibCompress/LZWDecoder.h>
#include <LibCompress/PackBitsDecoder.h>
#include <LibCompress/Zlib.h>
#include <LibGfx/ImageFormats/CCITTDecoder.h>
#include <LibGfx/ImageFormats/TIFFMetadata.h>
@ -280,6 +282,20 @@ private:
TRY(loop_over_pixels(move(decode_lzw_strip)));
break;
}
case Compression::AdobeDeflate: {
// This is an extension from the Technical Notes from 2002:
// https://web.archive.org/web/20160305055905/http://partners.adobe.com/public/developer/en/tiff/TIFFphotoshop.pdf
ByteBuffer decoded_bytes {};
auto decode_zlib = [&](u32 num_bytes) -> ErrorOr<ReadonlyBytes> {
auto stream = make<ConstrainedStream>(MaybeOwned<Stream>(*m_stream), num_bytes);
auto decompressed_stream = TRY(Compress::ZlibDecompressor::create(move(stream)));
decoded_bytes = TRY(decompressed_stream->read_until_eof(4096));
return decoded_bytes;
};
TRY(loop_over_pixels(move(decode_zlib)));
break;
}
case Compression::PackBits: {
// Section 9: PackBits Compression
ByteBuffer decoded_bytes {};