suppressed memory leaks - added image conversion support if the codec does not...

suppressed memory leaks - added image conversion support if the codec does not support YUV420P - added raw output (any comments are welcome to simplify the API)


git-svn-id: file:///var/local/repositories/ffmpeg/trunk@2072 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b