[FFmpeg-user] aspect ratio is changed with codec copy and sameq

[Rodney Baker]

On Wed, 21 Mar 2012 17:45:36 Carl Eugen Hoyos wrote:
> vrparekh <at> gmail.com <vrparekh <at> gmail.com> writes:
> >     Stream #0:0(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p,
> > 
> > 400x300 [SAR 300:400 DAR 1:1]
> 
> This is exactly the same as your input file shows.
> Where is the problem?
> 
> Carl Eugen
> 

Carl, I think the key is in this quote from a previous mail in this thread:

>one weird thing is when i see details in another video tool, it shows me
>sar=4:3
>dar=4:3
>of original video

>but when i use command ffpeg -i sourcefile, it shows me
>sar=300:400
>dar=1:1

In other words, ffmpeg appears to be detecting the SAR and DAR differently to 
"another video tool" and creating the output file the same as the alledgedly 
incorrectly detected input file aspect ratio (thus incorrectly altering the 
aspect ratio to something different from the source file. At least, that is 
how I read it. 

-- 
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Rodney Baker VK5ZTV
rodney.baker at iinet.net.au
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