- Changed the --enable-framegrab option to --with-framegrab since you specify the PNG library path on the configure line.
- Changed FrameGrabImage::writePNG() to FrameGrabImage::writeAsPNG().
- Added FrameGrabImage::toStringAsPNG() which returns the image as PNG data as a string. This allows the output to be fed straight in to GD without requiring an intermediate file.