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Further compression and png work.

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This commit is contained in:
James Grogan 2022-11-23 15:41:33 +00:00
parent 318b481ccc
commit 9c8faa534b
34 changed files with 1164 additions and 203 deletions
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19
src/image/PngReader.cpp
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@ -1,6 +1,10 @@
#include "PngReader.h"
#include "BinaryStream.h"
#include "BitStream.h"
#include "BufferBitStream.h"
#include "ZlibEncoder.h"
#include <iostream>
#include <sstream>
@ -84,12 +88,11 @@ void PngReader::readIDATChunk(unsigned length)
{
if (mAwaitingDataBlock)
{
mImageData.setCompressionMethod(mFile->readNextByte());
mImageData.setExtraFlags(mFile->readNextByte());
mImageData.setDataSize(length-2);
mEncoder->setCompressionMethod(mFile->readNextByte());
mEncoder->setExtraFlags(mFile->readNextByte());
for(unsigned idx=0; idx<length-2; idx++)
{
mImageData.setByte(idx, mFile->readNextByte());
mInputStream->writeByte(mFile->readNextByte());
}
mAwaitingDataBlock = false;
}
@ -97,7 +100,7 @@ void PngReader::readIDATChunk(unsigned length)
{
for(unsigned idx=0; idx<length; idx++)
{
mImageData.setByte(idx, mFile->readNextByte());
mInputStream->writeByte(mFile->readNextByte());
}
}
}
@ -135,10 +138,14 @@ std::unique_ptr<Image<unsigned char> > PngReader::read()
return image;
}
mInputStream = std::make_unique<BufferBitStream>();
mOutputStream = std::make_unique<BufferBitStream>();
mEncoder = std::make_unique<ZlibEncoder>(mInputStream.get(), mOutputStream.get());
while(readChunk())
{
}
mImageData.processData();
mEncoder->decode();
return std::move(image);
}