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Convert lz77 to use fixed buffer sizes.

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This commit is contained in:
James Grogan 2022-11-29 12:05:08 +00:00
parent a6e31c8d39
commit af6fad72eb
9 changed files with 362 additions and 110 deletions
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12
src/image/png/PngWriter.cpp
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@ -9,6 +9,7 @@
#include "PngFilter.h"
#include "Lz77Encoder.h"
#include "ZlibEncoder.h"
#include "HuffmanEncoder.h"
#include "CyclicRedundancyChecker.h"
#include "ByteUtils.h"
@ -181,10 +182,6 @@ void PngWriter::write(const std::unique_ptr<Image<unsigned char> >& image)
auto filter_out_stream = std::make_unique<BufferBitStream>();
PngFilter filter(raw_image_stream, filter_out_stream.get());
filter.encode();
//while(!filter_out_stream->isFinished())
//{
//std::cout << "Got pix " << static_cast<int>(*filter_out_stream->readNextByte()) << std::endl;
//}
filter_out_stream->resetOffsets();
@ -199,9 +196,12 @@ void PngWriter::write(const std::unique_ptr<Image<unsigned char> >& image)
lz77_out_stream = std::make_unique<BufferBitStream>();
Lz77Encoder lz77_encoder(filter_out_stream.get(), lz77_out_stream.get());
if (mCompressionMethod == Deflate::CompressionMethod::DYNAMIC_HUFFMAN)
if (mCompressionMethod == Deflate::CompressionMethod::FIXED_HUFFMAN)
{
// Set up custom encoder;
auto huffman_encoder = std::make_unique<HuffmanEncoder>();
huffman_encoder->setUseFixedCode(true);
huffman_encoder->initializeTrees();
lz77_encoder.setPrefixCodeGenerator(std::move(huffman_encoder));
}
lz77_encoder.encode();
lz77_out_stream->resetOffsets();