[Kdenlive-devel] Re: Too complex structure of source code

[Dan Dennedy]

On Saturday 07 January 2006 05:48, jb wrote:
> Sorry for the mess. By the way, I noticed the libdv producer is unable to
> get an image frame of a raw dv file. It seems to return an empty buffer.
> Using avformat returns a correct image from the frame. If you confirm this,
> it would be nice to either fix the bug or add a comment about this in the
> mlt's documentation...
>
> (I am using this code to get the frame:)
> _________
> Mlt::Frame *m_frame = m_producer.get_frame();
> (...)
> uchar *m_thumb = m_frame->fetch_image( mlt_image_rgb24a, width, height, 1
> ); QImage m_image( m_thumb, width, height, 32, 0, 0, QImage::IgnoreEndian
> ); _________

The libdv producer does not support the rgb24a image type. The avformat 
producer does not either; however, it does return yuv422 when you *request* 
rgb24a. Notice that image type is passed by reference so the service can 
change it; what you pass in is merely a request. Did you notice that you did 
not actually receive rgb24a from producer_avformat? Perhaps the libdv 
producer should be improved to behave similar to avformat: return something 
rather than nothing--I will fix that. However, another thing to bear in mind 
is that most everything in MLT was implemented and optimised with yuv422 in 
mind as the common image format. You should use it as much as possible.