[FFmpeg-devel] Gaining access to a encoder context in avformat?

Kevin Wheatley kevin.j.wheatley at gmail.com
Fri Feb 20 12:56:12 CET 2015

On Fri, Feb 20, 2015 at 11:44 AM, Michael Niedermayer <michaelni at gmx.at> wrote:
> If you start with a existing movie and copy the packets one by one
> there is no decoder and no encoder, so no dnxencoder structure
> if you want to put some value in the avid atom which are stored in the
> bitstream/packets of dnxhd and not in the generic data structures
> like width/height would be then you have to extract these from the
> dnxhd bitstream one way or another because thats the only thing thats
> there in the memory of your machine. I dont know what exact information
> you want/need from the dnxhd encoder ...

hmm, maybe I should just say that copy is not supported for DNxHD
files then as that sounds a pain to deal with, or I could put better
check in the arbitrary buffer offsets the mov_write_avid_tag function
uses to access track->vos_data, which is what sent me down the
direction of trying to access the encoder data. Is there a sensible
function I can use to find a specific atom within the buffer?

On a related note when doing a -c copy is it supposed to preserve
color range (trc, space, primaries) in the output if it is set on the
input/command line?



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