Re: grab a specific frame and save uncompressed

-----Original Message-----
From: emanuele fumagalli <emanuele.fumagalli <at> babelgum.com>

Hi all,
I'm looking for a way to grab a specific frame number with ffmpeg.
Now I'm using
ffmpeg -y -i mallard.mp4 -ss 00:00:07.500 -vframes 1 -an test%d.jpg

But the resulting jpg is compressed, is there a way to have it lossless?
Besides I'm not sure I'm getting the frame I want, is there a way to specify the 
exact frame number?
Will I have the closest I frame or the exact frame I required?
_______________________________________________

You can output to bmp using the -vcodec bmp option. I usually export a couple of 
seconds to be sure I get the frame I want. Then I just delete the extras. I don't 
think it matters what kind of frame it is because, IIRC, FFmpeg will process from 
the start of the file to the stop point set by the -vframes or -t options.

BTW: I normally output to png or tiff instead of jpeg. They just look better to me.

Rip

Re: searchable list

joshua <at> crackcreative.com wrote:
> Is there a searchable version of this mailing list so that I don't ask  
> stupid questions that have been asked many times before?

If google is your preferred tool, you can add the term 
"site:lists.mplayerhq.hu/pipermail/" in the query box.

--

-- 
Andy

Re: problem compiling ffmpeg [URGENT]

Joao Patricio wrote:
> Hi there,
>
> I'm trying to compile ffmpeg using mingw+msys following this step-by-step
> guide http://arrozcru.no-ip.org/ffmpeg_wiki/tiki-index.php?page=Introduction.
> When I get to "Building FFmpeg SVN statically" and issue ./configure
> --enable-memalign-hack I get this:
>
> gcc is unable to create an executable file.
> If gcc is a cross-compiler, use the --enable-cross-compile option.
> Only do this if you know what cross compiling means.
> C compiler test failed.
> If you think configure made a mistake, make sure you are using the latest
> version from SVN.  If the latest version fails, report the problem to the
> ffmpeg-user <at> mplayerhq.hu mailing list or IRC #ffmpeg on irc.freenode.net.
> Include the log file "config.err" produced by configure as this will help
> solving the problem.
>
> I have no clue on what's wrong, any ideas?
>
> I'll attach my config.err. Line 1526 caught my attention "gcc.exe:
> installation problem, cannot exec `as': No such file or directory"
>
> Hope you can help me.
>
>

Hi,
the error message suggests binutils is missing or not installed, it has 
to do with cross compiling.

Re: config.err

* Martin Orlob on Wednesday, May 21, 2008 at 21:53:24 -0600
> my goal is to use ffmpeg this way:
> 
> $ ./ffmpeg/ffmpeg -b 500kb/s -antialias auto -i test.mpg -vcodec flv -ab 
> 48 -ar 22050 -s 420x276 -r 15 -y video.flv
> 
> I run xubuntu 8.04
> 
> and "uname -a" output:
> 
> Linux marlux 2.6.24-16-generic #1 SMP Thu Apr 10 13:23:42 UTC 2008 i686 
> GNU/Linux
> 
> 
> 
> So to do that I did:
> 1) sudo apt-get install liblame-dev lame
> 2) sudo apt-get install subversion build-essential
> 3) svn checkout svn://svn.mplayerhq.hu/ffmpeg/trunk ffmpeg
> 4) cd ffmpeg
> 5) 
> $ ./configure --enable-gpl --enable-libdc1394 --enable-libgsm --enable-libmp3lame
--enable-libfaad --enable-libfaac --enable-libxvid --enable-pthreads --disable-debug
--prefix=/usr --disable-vhook
> 
> Then I got this output on the shell:
> 
> FAAD test failed.

Apparently you don't have faad2 installed.

R: grab a specific frame and save uncompressed

>You can output to bmp using the -vcodec bmp option. I usually export a couple of 
>seconds to be sure I get the frame I want. Then I just delete the extras. I don't 
>think it matters what kind of frame it is because, IIRC, FFmpeg will process from 
>the start of the file to the stop point set by the -vframes or -t options.

>BTW: I normally output to png or tiff instead of jpeg. They just look better to me.

Hi, thanks a lot for answering.
Just one question: How can you determine the exact frame and delete the extras?
Let's say what is the command line to get frame 100?
And, to output to tiff would it be enough to put -vcodec tiff?

Thanks

_______________________________________________
ffmpeg-user mailing list
ffmpeg-user <at> mplayerhq.hu
https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-user

Re: R: grab a specific frame and save uncompressed

-----Original Message-----
From: emanuele fumagalli <emanuele.fumagalli <at> babelgum.com>

>You can output to bmp using the -vcodec bmp option. I usually export a couple 
of 
>seconds to be sure I get the frame I want. Then I just delete the extras. I 
don't 
>think it matters what kind of frame it is because, IIRC, FFmpeg will process 
from 
>the start of the file to the stop point set by the -vframes or -t options.

>BTW: I normally output to png or tiff instead of jpeg. They just look better to 
me.

Hi, thanks a lot for answering.
Just one question: How can you determine the exact frame and delete the extras?
Let's say what is the command line to get frame 100?
And, to output to tiff would it be enough to put -vcodec tiff?

_______________________________________________

If you want frame 100 from an ntsc video you would use "-ss 00:00:03.333 -vframes 1"? that would give you the
100th frame if you count, as I do, from 1.

In reality, I would just use "-vframes 100" from the start of the file and then delete the ones I don't want.
Each frame, in ntsc takes about 0.033 seconds, multiply that by the frame number you want then convert to
hh:mm:ss.nnn . That is not exactly correct because there are really not quite 30 frames per second, but it
is close. I would really use something like "-ss 00:00:03.320" to get the 100th frame.

And yes, to output to tiff you would use -vcodec tiff. 

Re: "-target" switches

Tobias Brockamp wrote:
> The -f ipod is only for files which have 640x480 resolution and should  
> be played on 5th generation ipods (not
> tested on a nano), for touch and iphone it is no problem to leave it.

This is false. I make files that are 480x272 h.264 for the iPod Touch 
and the -f ipod switch is needed.
That was, in fact, the reason why I coded that switch in the first place.
Although I make the actual files in mencoder because of the filter 
chains that are available.

--

-- 
Mark

Unknown decoder 'ac3'

Hello,

I am trying to do the following:

$ ffmpeg -target pal-dvd -i ./Der\ Untergang.m2t untergang.mpeg
FFmpeg version SVN-r13246, Copyright (c) 2000-2008 Fabrice Bellard, et al.

configuration: --enable-gpl --enable-pthreads --enable-libvorbis --enable-libtheora
--enable-libgsm --disable-debug --enable-libmp3lame --enable-libfaadbin --enable-libfaad
--enable-libfaac --enable-liba52 --enable-shared --enable-libxvid --enable-liba52 --enable-nonfree
  libavutil version: 49.6.0
  libavcodec version: 51.57.0
  libavformat version: 52.14.0
  libavdevice version: 52.0.0
  built on May 23 2008 14:18:07, gcc: 4.2.3 (Ubuntu 4.2.3-2ubuntu7)
Unknown decoder 'ac3'

But what about this:

$ ffmpeg -formats
FFmpeg version SVN-r13246, Copyright (c) 2000-2008 Fabrice Bellard, et al.

configuration: --enable-gpl --enable-pthreads --enable-libvorbis --enable-libtheora
--enable-libgsm --disable-debug --enable-libmp3lame --enable-libfaadbin --enable-libfaad
--enable-libfaac --enable-liba52 --enable-shared --enable-libxvid --enable-liba52 --enable-nonfree
  libavutil version: 49.6.0
  libavcodec version: 51.57.0
  libavformat version: 52.14.0
  libavdevice version: 52.0.0
  built on May 23 2008 14:18:07, gcc: 4.2.3 (Ubuntu 4.2.3-2ubuntu7)

Re: compiling ffmpeg

After trying various configure combinations, I took out the --enable-shared
switch and it seemed to work fine.

What does this switch do?

Re: Compiling ffmpeg with extra libs without root access

-----Original Message-----
From: Jakob Dam Jensen <jakobdj <at> gmail.com>

This is my problem - how do I tell ffmpeg explicitly where to look for  
extra libs?
_______________________________________________

Try --extra-libs=/path/to/libs? with your configure command.

Rip