[FFmpeg-user] converting 1080 to 720 mpeg2

[Ian Evans]

On Wed, Feb 29, 2012 at 3:46 AM, Andy Sheen <sheen.andy at googlemail.com> wrote:
> What does ffprobe (or similar) say the  file formats are now. I think
> specifying the yadif=1 will give 1 frame for every field which would give
> you 59.99 fps, but you've probably overriden that with the -r line.
>
> Basically, you need to get the two files with exactly the same size, same
> rate (which will be ~60fps), same interlacing (i.e. none as the 720 is
> progressive)


Okay here's ffprobe on the 720 file:
Duration: 00:17:40.20, start: 0.338367, bitrate: 11065 kb/s
Stream #0.0[0x1e0]: Video: mpeg2video (Main), yuv420p, 1280x720 [PAR
1:1 DAR 16:9], 65000 kb/s, 59.96 fps, 59.96 tbr, 90k tbn, 119.88 tbc
Stream #0.1[0x80]: Audio: ac3, 48000 Hz, 5.1, s16, 384 kb/s

and on the 1080 test file after using this command line:
 sudo ffmpeg -i 1662_20120226204000.mpg -t 00:5:00.000 -f mpegts
-vcodec mpeg2video -qscale 2  -vf 'yadif=1,scale=1280:720'
video-01.mpeg.ts

Stream #0.0[0x100]: Video: mpeg2video (Main), yuv420p, 1280x720 [PAR
1:1 DAR 16:9], 104857 kb/s, 29.97 fps, 29.97 tbr, 90k tbn, 59.94 tbc
Stream #0.1[0x101]: Audio: mp2, 48000 Hz, stereo, s16, 64 kb/s

So it looks like my command line didn't get the frame rate doubled on
the test file. Also it seems to have chosen the second of the two
available audio tracks, which were:

Stream #0.1[0x80]: Audio: ac3, 48000 Hz, 5.1, s16, 384 kb/s
Stream #0.2[0x81]: Audio: ac3, 48000 Hz, stereo, s16, 128 kb/s

I did try using a -map 0:a to get all the audio tracks but I'm
guessing that's wrong too as I got a "Number of stream maps must match
number of output streams" error.