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Continue work on png writer.

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This commit is contained in:
James Grogan 2022-11-23 17:51:36 +00:00
parent 9c8faa534b
commit 86bc0d89f6
19 changed files with 225 additions and 19 deletions
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45
src/image/PngWriter.cpp
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@ -9,6 +9,8 @@
#include "Lz77Encoder.h"
#include "ByteUtils.h"
#include <stdio.h>
PngWriter::PngWriter()
@ -34,15 +36,49 @@ void PngWriter::setPath(const Path& path)
void PngWriter::writeSignature()
{
mOutStream->writeByte(Png::getHighBitCheck());
for (auto byte : Png::getSignature())
{
mOutStream->writeByte(byte);
}
mOutStream->writeBytes(StringUtils::toBytes(Png::getName()));
mOutStream->writeBytes(Png::getSignature());
}
void PngWriter::writeHeader()
{
writeSignature();
Png::IHDRChunk header_chunk;
header_chunk.width = mWorkingImage->getWidth();
header_chunk.height = mWorkingImage->getHeight();
header_chunk.bitDepth = mWorkingImage->getBitDepth();
header_chunk.colorType = 6;
auto length = header_chunk.getLength();
auto crc = header_chunk.getCrc();
unsigned num_bytes = sizeof(uint32_t);
for(unsigned idx=0; idx<num_bytes;idx++)
{
mOutStream->writeByte(ByteUtils::getByteN(length, idx));
}
mOutStream->writeBytes(StringUtils::toBytes(header_chunk.name));
for(unsigned idx=0; idx<num_bytes;idx++)
{
mOutStream->writeByte(ByteUtils::getByteN(header_chunk.width, idx));
}
for(unsigned idx=0; idx<num_bytes;idx++)
{
mOutStream->writeByte(ByteUtils::getByteN(header_chunk.height, idx));
}
mOutStream->writeByte(header_chunk.bitDepth);
mOutStream->writeByte(header_chunk.colorType);
mOutStream->writeByte(header_chunk.compressionMethod);
mOutStream->writeByte(header_chunk.filterMethod);
mOutStream->writeByte(header_chunk.interlaceMethod);
for(unsigned idx=0; idx<num_bytes;idx++)
{
mOutStream->writeByte(ByteUtils::getByteN(crc, idx));
}
}
void PngWriter::write(const std::unique_ptr<Image<unsigned char> >& image)
@ -50,6 +86,7 @@ void PngWriter::write(const std::unique_ptr<Image<unsigned char> >& image)
if (!mPath.empty())
{
mWorkingFile = std::make_unique<File>(mPath);
mWorkingFile->SetAccessMode(File::AccessMode::Write);
mWorkingFile->Open(true);
mOutStream = std::make_unique<OutputBitStream>(mWorkingFile->GetOutHandle());
}