[FFmpeg-devel] [PATCH] nvenc: Compensate for hardware trying to mess with aspect ratio of DVD content.

[Kieran Kunhya]

On 18 January 2015 at 12:22, Michael Niedermayer <michaelni at gmx.at> wrote:
> On Sun, Jan 18, 2015 at 02:52:59AM +0100, Hendrik Leppkes wrote:
>> On Sun, Jan 18, 2015 at 1:02 AM, Nicolas George <george at nsup.org> wrote:
>>
>> > L'octidi 28 nivôse, an CCXXIII, Kieran Kunhya a écrit :
>> > > Oops I misunderstood, you mean the software must comply with the users
>> > wishes.
>> >
>> > Yes.
>> >
>> > > Anyway my argument is that BT601 should be the default for the these
>> > > resolutions.
>> >
>> > If you want, but that must happen immediately when the contents enters into
>> > FFmpeg's data structure, not at a random point in the processing chain.
>> >
>> >
>> Without arguing for or against BT.601 behaviour...
>>
>> nvenc should behave the same as libx264, or any other video encoder, if
>> this patch makes it do that, then it should be applied.
>
> Yes, and AFAICS an earlier mail from philip indicates this is the case
> "
>     Stream #0:0: Video: rawvideo (RGB[24] / 0x18424752), rgb24, 720x576
>     [SAR 64:45 DAR 16:9], 25 tbr, 25 tbn, 25 tbc
>
>     With libx264, I get the same SAR and DAR out.
>
>     With nvenc, I get:
>
>     sample_aspect_ratio=16:11
>     display_aspect_ratio=20:11
> "
>
> In above example the user asks for a NON BT.601 format 720x576 at
> SAR 64:45 and a DAR related to 720x576 NOT 702 or 704x576 of 16:9
> yet nvenc gives her something else

Here's the point where I give up and start my own fork where things
are done properly.