Info about DVINFO
Hi everybody,
can somebody help me in figuring out how to use the DVINFO structure with the DV Encoder? Specifically, I am interested in setting the 16:9-flag which can found in the Video Control Section (VAUX). Is this the right way to create a 16:9 DV avi?
Well, I am able to set the DVINFO structure to various values by using the appropriate interface on the DV Encoder, but this seems to have no effect on the resultant output file. It always plays or is read by other applications as normal 4:3 avi...
I guess I am missing something... - cpix
[575 byte] By [
cpix] at [2008-2-22]
well, changing the resolution to a 16:9 value is not possible - the DV Encoder can only be set to standard PAL or NTSC values (for example 720x576 PAL). You simply can not specify other resolutions. Even if it would be possible, it would be of no use (read below - the 16:9 flag is not a global setting!)
Actually, I researched a little bit further: the aspect ratio of DV data is stored at several places in an avi file, not only the DVINFO structure. In fact, every single frame carries this information with it, and by misuse of a hex editor one can create avis which switch in the middle of the video stream from 4:3 to 16:9 and back. Newer versions of Directshow with VMR9 handle such an DV avi file gracefully, but not all programs are able to.
Beside this, the DVINFO which shows up in the final avi seems not to care what is set by an appropriate interface call to the DV Encoder. Whatever is written to the Encoder, in the final avi just some fixed default values are used (defaulting of course to 4:3). Funny....
Anyway, is nobody out there who has some knowledge about 16:9 DV material and the correct way to store it with Directshow to a file? Afterall, this is a Directshow Developer Forum...
- cpix
