Use PixelBuffer objects as the interface for encoders and decoders
This avoid a lot of unnecessary middle men. This also pushes the
responsibility for pixel format conversion into the encoders and
decoders. The new bufferFromBuffer() is used for direct conversion,
rather than PixelTransformer/TransImageGetter.
Encoders/decoders should track the connection object
The connection object is a much more appropriate object for the
decoders and encoders to keep track of. Besides the streams, it also
contains state like connection parameters.
Pierre Ossman
Constantin Kaplinsky