void FExrImageWrapper::CompressRaw(const sourcetype* SrcData, bool bIgnoreAlpha)
{
uint32 NumWriteComponents = GetNumChannelsFromFormat(RawFormat);
if (bIgnoreAlpha && NumWriteComponents == 4)
{
NumWriteComponents = 3;
}
Imf::Header Header(Width, Height);
for (uint32 Channel = 0; Channel < NumWriteComponents; Channel++)
{
Header.channels().insert(GetRawChannelName(Channel), Imf::Channel(OutputFormat));
}
FMemFileOut MemFile("");
Imf::FrameBuffer ImfFrameBuffer;
TArray<uint8> ChannelOutputBuffers[4];
for (uint32 Channel = 0; Channel < NumWriteComponents; Channel++)
{
WriteFrameBufferChannel<OutputFormat>(ImfFrameBuffer, GetRawChannelName(Channel), SrcData + Channel, ChannelOutputBuffers[Channel]);
}
Imf::OutputFile ImfFile(MemFile, Header);
ImfFile.setFrameBuffer(ImfFrameBuffer);
ImfFile.writePixels(Height);
CompressedData = MemFile.Data;
}
void FExrImageWrapper::WriteFrameBufferChannel(Imf::FrameBuffer& ImfFrameBuffer, const char* ChannelName, const sourcetype* SrcData, TArray<uint8>& ChannelBuffer)
{
const int32 OutputPixelSize = ((OutputFormat == Imf::HALF) ? 2 : 4);
ChannelBuffer.AddUninitialized(Width*Height*OutputPixelSize);
uint32 SrcChannels = GetNumChannelsFromFormat(RawFormat);
ExtractAndConvertChannel(SrcData, SrcChannels, Width, Height, (typename TExrImageOutputChannelType<OutputFormat>::Type*)&ChannelBuffer[0]);
Imf::Slice FrameChannel = Imf::Slice(OutputFormat, (char*)&ChannelBuffer[0], OutputPixelSize, Width*OutputPixelSize);
ImfFrameBuffer.insert(ChannelName, FrameChannel);
}
void FExrImageWrapper::CompressRaw(const sourcetype* SrcData, bool bIgnoreAlpha)
{
const double StartTime = FPlatformTime::Seconds();
uint32 NumWriteComponents = GetNumChannelsFromFormat(RawFormat);
if (bIgnoreAlpha && NumWriteComponents == 4)
{
NumWriteComponents = 3;
}
Imf::Compression Comp = bUseCompression ? Imf::Compression::ZIP_COMPRESSION : Imf::Compression::NO_COMPRESSION;
Imf::Header Header(Width, Height, 1, Imath::V2f(0, 0), 1, Imf::LineOrder::INCREASING_Y, Comp);
for (uint32 Channel = 0; Channel < NumWriteComponents; Channel++)
{
Header.channels().insert(GetRawChannelName(Channel), Imf::Channel(OutputFormat));
}
FMemFileOut MemFile("");
const int32 OutputPixelSize = ((OutputFormat == Imf::HALF && bUseCompression) ? 2 : 4);
MemFile.Data.AddUninitialized(Width * Height * NumWriteComponents * OutputPixelSize);
Imf::FrameBuffer ImfFrameBuffer;
TArray<uint8> ChannelOutputBuffers[4];
for (uint32 Channel = 0; Channel < NumWriteComponents; Channel++)
{
WriteFrameBufferChannel<OutputFormat>(ImfFrameBuffer, GetRawChannelName(Channel), SrcData + Channel, ChannelOutputBuffers[Channel]);
}
Imf::OutputFile ImfFile(MemFile, Header);
ImfFile.setFrameBuffer(ImfFrameBuffer);
ImfFile.writePixels(Height);
CompressedData.AddUninitialized(MemFile.tellp());
FMemory::Memcpy(CompressedData.GetData(), MemFile.Data.GetData(), MemFile.tellp());
const double DeltaTime = FPlatformTime::Seconds() - StartTime;
UE_LOG(LogImageWrapper, Verbose, TEXT("Compressed image in %.3f seconds"), DeltaTime);
}