[MEncoder-users] unable to encode to dvvideo - can't initialize dv format!

[Reimar Döffinger]

On Sun, Mar 15, 2009 at 12:23:48AM +0100, Jelle de Jong wrote:
> Killer issues I still have is the major cpu load making it impossible to
> do a live recording see my previous other email tread on the mailinglist
> for this.

DV is more optimized for hardware encoding than software. Also nobody
cares much about it so it lacks SIMD optimizations, and in addition to
that it is a high bitrate codec.

> (see also the yuv422p -> yuv420p can I make mencoder output yuv420p)

Maybe by removing the "format=422P" part?


> $ ffmpeg -i output0.dv -target pal-dv output1.dv
> Input #0, dv, from 'output0.dv':
>   Duration: 00:00:00.84, start: 0.000000, bitrate: 57600 kb/s
>     Stream #0.0: Video: dvvideo, yuv422p, 720x576, 57600 kb/s, PAR 59:54
> DAR 295:216, 25 tbr, 25 tbn, 25 tbc
>     Stream #0.1: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
>     Stream #0.2: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
> Output #0, dv, to 'output1.dv':
>     Stream #0.0: Video: dvvideo, yuv420p, 720x576 [PAR 59:54 DAR
> 295:216], q=2-31, 200 kb/s, 90k tbn, 25 tbc
>     Stream #0.1: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
> 
> The ffmpeg output seems more then 50% smaller in file size (see
> output0.log) why is this?

Because the 4:2:2 DV format is 50 MBit/s and the 4:2:0 format is 25
MBit/s.
I'd expect the duplicate audio streams to be an FFmpeg bug, but not
really sure.