HOWTO: Install and use the latest FFmpeg and x264

[FakeOutdoorsman]

It's better to add zero step:

LC_LANG="en_US.utf8"

because output of svn info is locale sensitive.

Thanks. I didn't know this and will look into it. What happens when a non-en_US.utf8 locale is used and LC_LANG="en_US.utf8" is not set?

Just did a test run converting a .ogv (recordMyDesktop file) to a mp4 using ffmpeg (built using this threads tutorial).

$ ffmpeg -i all-in-one-seo-img-2.ogv -acodec libfaac -ab 128k -ac 2 -vcodec libx264 -vpre slow -crf 22 -threads 0 output.mp4

I must say it went very well and quality seems to be good. Any tips or remarks on the way I converted this file?

Looks good to me, but it depends on what your output is for (portable device, upload to video site, playing on computer, etc). Other things you can try:

Record your next screencast with this guide: HOWTO: Proper Screencasting on Linux. It's a great guide and will probably provide a better quality output than anything from recordMyDesktop.

Encode your audio with neroAacEnc. Many people claim it's a better encoder than libfaac. Example:

ffmpeg -i input.foo -f wav - | neroAacEnc -ignorelength -if - -of audio.mp4
ffmpeg -i input.foo -i audio.mp4 -vcodec copy -acodec copy -map 0:0 -map 1:0 output-combined.mkv

Or simply copy the audio from the original and throw it into a MKV container which handles just about anything:

ffmpeg -i input.foo -acodec copy -vcodec libx264 -vpre slow -crf 22 -threads 0 output.mkv

Or use -aq instead of -ab, such as -aq 100 (the -aq values vary between encoders). From faac --long-help:

Set default variable bitrate (VBR) quantizer quality in percent. (default: 100, averages at approx. 120 kbps VBR for a normal stereo input file with 16 bit and 44.1 kHz sample rate; max. value 500, min. 10).

Try other -vpre presets and change -crf. Increase the CRF value until it reaches an unacceptable quality, and then use the previous value. Add -t 30 to your command to encode just 30 seconds for a test clip that may give you a general idea of how things can look without needing to encode the whole video.

[Bachstelze]

Thanks. I didn't know this and will look into it. What happens when a non-en_US.utf8 locale is used and LC_LANG="en_US.utf8" is not set?

Absolutely nothing, because the output of svn info generally contains only ASCII characters. And most users will have an UTF-8 locale anyway.

[leonidv]

Thanks. I didn't know this and will look into it. What happens when a non-en_US.utf8 locale is used and LC_LANG="en_US.utf8" is not set?

Here are my default svn info output (ru_RU.UTF-8):

<09:12:34> ffmpeg: locale
LANG=ru_RU.utf8
<..skipped...>
<09:12:34> ffmpeg: svn info
Путь: '.'
URL: svn://svn.ffmpeg.org/ffmpeg/trunk
Корень репозитория: svn://svn.ffmpeg.org/ffmpeg
UUID репозитория: 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b
Редакция: 24040
Вид узла: каталог
Задано: нормально
Автор последнего изменения: ramiro
Редакция последнего изменения: 24040
Дата последнего изменения: 2010-07-04 21:24:57 +0400 (Вск, 04 Июл 2010)

So,

sudo checkinstall --pkgname=ffmpeg --pkgversion "4:SVN-r`svn info | grep Revision | awk '{ print $NF }'`" --backup=no --default

doesn't work.

[leonidv]

Absolutely nothing, because the output of svn info generally contains only ASCII characters. And most users will have an UTF-8 locale anyway.

UTF-8 is not locale

[Bachstelze]

UTF-8 is not locale

That's why I said "an UTF-8 locale". I admit I didn't test for exotic locales, though... Anyway, better use C than en_US then, not everyone might have it installed.

[flyone]

The command "sudo checkinstall --pkgname=ffmpeg --pkgversion "5:0.5.1" --backup=no --default" worked for me.
It seems like it is "`svn info | grep Revision | awk '{ print $NF }'`" that made the problem.

Thanks anyway

Hello i got the same problem... change "grep Revision" to "grep Révision"... because we are french we have somme anoying accent...



sorry for my poor english

[nothingspecial]

Do you happen to know how to do this easily on a minimal install without it wanting to pull X in?

Full ffmpeg, no X?

[leonidv]

Hello i got the same problem... change "grep Revision" to "grep Révision"... because we are french we have somme anoying accent...



sorry for my poor english

You can do it before compiling:
http://ubuntuforums.org/showpost.php...postcount=1109
Then all svn messages will be in English.

[andrew.46]

Hi flyone,

Hello i got the same problem... change "grep Revision" to "grep Révision"... because we are french we have somme anoying accent...

I love fiddling with these things:

svn info | sed '5!d' | awk '{ print $NF }'

Would always work unless the number of lines changed, reasonably unlikely... A variation:

svn info | sed -e '5!d' -e 's/^.\{10\}//'

Andrew

[Tom Dignan]

Wow, thanks for making what would otherwise have been a formidable task quite easy. I did have install libopencore-amrnb-dev, which isn't listed in your post as a dependency.