[FFmpeg-devel] [PATCH] avdevice/decklink_dec: Extract 1080i and NTSC VANC

[Devin Heitmueller]

Hi Ray,

> 
> Please find updated patch attatched. I reverted the vanc lines changes and
> found that all my tests worked as expected, so not sure what was wrong w/
> my original test. The need to extract vanc from the entire line vs just the
> luma in NTSC is still required.

It’s helpful if in the future you could not do patches as attachments.  It makes it harder for people to comment on them.

Glad to hear you didn’t need to adjust any of the VANC line definitions in order to work properly.  I think they do still need some more review, but at least we don’t need to commit to any values at this time which would violate the spec.

Regarding the luma/chroma extraction, I haven’t looked at your code too closely, but isn’t the destination array too small?  If MAX_WIDTH_VANC is 1920, presumably intended to be the number of pixels, then you would need three times as many uint16_t values in your destination array if you wanted Y, U, and V, or else you would overflow the buffer.  Right?  In either case, you probably want some bounds protection to ensure GetWidth() never returns a size greater than your destination array.

Also, could you send me a copy of the array of V210 bytes you are testing with (i.e. just jam a printf loop into the code and dump the whole thing out)?  Would be useful to have it here so I can ensure that libklvanc works properly as well (and add it to the list of test vectors I bundle with the library).  If you can’t that’s fine - I’ll eventually get around to doing some SD testing here.

Devin