On 17 January 2015 at 18:14, Nicolas George <geo...@nsup.org> wrote: > Le septidi 27 nivôse, an CCXXIII, Philip Langdale a écrit : >> On Fri, 16 Jan 2015 22:17:56 +0100 >> Nicolas George <geo...@nsup.org> wrote: >> Ok. I did this test and it produces correct results - SAR 133:221 which >> yields the correct final aspect ratio, > > This is a good start. > >> but if I try and do a real world >> case, like my PAL DVD, it goes wrong - and Timo's patch goes wrong too, >> with this same weird 1.02 (45/44) scale factor. > > The 45/44 value looks like 704/720: the sign that some people long time ago > in committees in the broadcast industry could not agree whether the aspect > ratio applies to the whole image or only the part that is displayed on > screen.
The active picture width is 702 pixels. I would read the following thread and ETSI TS 101 154 for more information about SAR/DAR etc https://lists.libav.org/pipermail/ffmpeg-user/2010-March/024551.html I haven't quite followed what's going on to decide whether Nvidia or FFmpeg is correct. Kieran _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
