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Initial fixed huffman coding for png.

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This commit is contained in:
James Grogan 2022-11-28 10:16:04 +00:00
parent e4f9393ee7
commit 7f5009fb5e
39 changed files with 1294 additions and 440 deletions
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11
src/compression/deflate/DeflateEncoder.cpp
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@ -1,6 +1,7 @@
#include "DeflateEncoder.h"
#include "BitStream.h"
#include "ByteUtils.h"
#include "DeflateBlock.h"
#include "BufferBitStream.h"
@ -22,6 +23,7 @@ bool DeflateEncoder::encode()
uint16_t count = 0;
BufferBitStream stream;
std::unique_ptr<DeflateBlock> working_block = std::make_unique<DeflateBlock>(&stream, mOutputStream);
working_block->setCompressionMethod(mCompressionMethod);
AbstractChecksumCalculator* checksum_calc;
if (mChecksumCalculators.size() > 0)
@ -38,15 +40,22 @@ bool DeflateEncoder::encode()
working_block->write(count);
working_block = std::make_unique<DeflateBlock>(&stream, mOutputStream);
working_block->setCompressionMethod(mCompressionMethod);
stream.reset();
}
if (auto byte = mInputStream->readNextByte())
{
std::cout << "Adding byte " << ByteUtils::toString(*byte) << " to deflate block input" << std::endl;
stream.writeByte(*byte);
}
else
{
if (const auto& remaining_bits = mInputStream->getRemainingBits(); remaining_bits.second > 0)
{
stream.writeNBits(remaining_bits.first, remaining_bits.second);
}
stream.resetOffsets();
working_block->setIsFinalBlock(true);
@ -56,7 +65,7 @@ bool DeflateEncoder::encode()
}
count++;
}
mOutputStream->flushRemainingBits();
mOutputStream->clearChecksumCalculator();
return true;
}