Re: aspect ratio is changed with codec copy and sameq
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
>of original video
>but when i use command ffpeg -i sourcefile, it shows me
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.
> >one weird thing is when i see details in another video tool, it shows me
> >of original video
> >but when i use command ffpeg -i sourcefile, it shows me
> In other words, ffmpeg appears to be detecting the SAR and DAR
> differently to "another video tool"
My answer was:
"If the input file is decoded incorrectly, please provide a sample."
I assumed the original report was about FFmpeg destroying some
information when remuxing the stream. That some information is
possibly read incorrectly sounds different to me.