bool ImageSegmenter::_generateRaw( const ImageWrapper& image,
const Handler& handler ) const
{
const SegmentParametersList& paramList = _generateSegmentParameters( image );
// resulting Raw segments
for( SegmentParametersList::const_iterator it = paramList.begin();
it != paramList.end(); ++it )
{
Segment segment;
segment.parameters = *it;
segment.imageData.reserve( segment.parameters.width *
segment.parameters.height *
image.getBytesPerPixel( ));
if( paramList.size() == 1 )
{
// If we are not segmenting the image, just append the image data
segment.imageData.append( (const char*)image.data,
int(image.getBufferSize( )));
}
else // Copy the image subregion
{
// assume imageBuffer isn't padded
const size_t imagePitch = image.width * image.getBytesPerPixel();
const size_t offset = segment.parameters.y * imagePitch +
segment.parameters.x * image.getBytesPerPixel();
const char* lineData = (const char*)image.data + offset;
for( unsigned int i = 0; i < segment.parameters.height; ++i )
{
segment.imageData.append( lineData, segment.parameters.width *
image.getBytesPerPixel( ));
lineData += imagePitch;
}
}
if( !handler( segment ))
return false;
}
return true;
}
QByteArray ImageJpegCompressor::computeJpeg(const ImageWrapper& sourceImage,
const QRect& imageRegion)
{
// tjCompress API is incorrect and takes a non-const input buffer, even
// though it does not modify it. It can "safely" be cast to non-const
// pointer to comply to the incorrect API.
unsigned char* tjSrcBuffer = (unsigned char*)sourceImage.data;
tjSrcBuffer +=
imageRegion.y() * sourceImage.width * sourceImage.getBytesPerPixel();
tjSrcBuffer += imageRegion.x() * sourceImage.getBytesPerPixel();
const int tjWidth = imageRegion.width();
// assume imageBuffer isn't padded
const int tjPitch = sourceImage.width * sourceImage.getBytesPerPixel();
const int tjHeight = imageRegion.height();
const int tjPixelFormat = getTurboJpegFormat(sourceImage.pixelFormat);
unsigned char* tjJpegBuf = 0;
unsigned long tjJpegSize = 0;
const int tjJpegSubsamp = TJSAMP_444;
const int tjJpegQual = sourceImage.compressionQuality;
const int tjFlags = 0; // or: TJFLAG_BOTTOMUP
int err = tjCompress2(_tjHandle, tjSrcBuffer, tjWidth, tjPitch, tjHeight,
tjPixelFormat, &tjJpegBuf, &tjJpegSize, tjJpegSubsamp,
tjJpegQual, tjFlags);
if (err != 0)
{
std::cerr << "libjpeg-turbo image conversion failure" << std::endl;
return QByteArray();
}
// move the JPEG buffer to a byte array
const QByteArray jpegData((char*)tjJpegBuf, tjJpegSize);
// free the libjpeg-turbo allocated memory
tjFree(tjJpegBuf);
return jpegData;
}
