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FFmpeg Makes an Official Release!
It’s been a long while since I’ve posted on this blog, but finally today something has spurned me into action.
Kino 1.3.0 Released
Yesterday a new version of popular Linux video editing tool, Kino, was released. The new version is 1.3.0 and contains the following changes:
- Updated export scripts for FFmpeg changes (x264, mp3)
- Improved speed on SMP systems by enabling FFmpeg multi-threaded codecs
- Improved import (DV conversion) progress dialog
- Added gstreamer-based Ogg Theora to the blip.tv publishing script
- Added quality level option to the blip.tv publishing script
- Updated Hungarian translation
- Added Ukranian translation by Yuri Chornoivan
Congratulations to Dan Kennedy and the team.
The new source files can be downloaded directly from here.
How-To: Alter Video Speed with FFmpeg and mjpegtools
Unfortunately my Linux based non-linear editing tool of choice, Open Movie Editor, doesn’t currently support directly altering video playback speed. For example, if you wanted a portion of your new compilation to run at 200% of original recorded speed, it can’t be done within OME. This exact functionality was something I needed for an existing editing project.
After some thought and investigation, such changes can be achieved through using a combination of FFmpeg and yuvfps, which is part of mjpeg tools, to alter the framerate of the desired footage. If your original file is PAL based, with a framerate of 25fps, changing the framerate to 50fps will result in the video running twice as fast, for half as long.
I didn’t initially have mjpegtools installed, but on my Debian based system this was easy enough with
sudo apt-get install mjpegtools
Next, the input video needs to be converted to yuv4mpegpipe format, passed through yuvfps and output to a new avi file. Here’s the command line I used to create a clip at 50fps:
ffmpeg -i input.dv -f yuv4mpegpipe - | yuvfps -s 50:1 -r 50:1 | ffmpeg -f yuv4mpegpipe -i - -b 28800k -y output.avi
Change the 50:1 ratios to whatever framerate you require. e.g. 100:1 for 100fps. Be sure to set the output file bitrate to a relevant quality level. Omitting this flag will result in a poor quality AVI output file by default.
The resulting AVI file was easily played back with Totem, and handled on the timeline admirably by OME.
Thanks to Victor Paesa on the FFmpeg mailing list for pointing me in the right direction.
Some other options to investigate include the new Libavfilter for FFmpeg and converting the original footage to a raw data file, which will lost the audio.
How-To: Extract images from a video file using FFmpeg
Extracting all frames from a video file is easily achieved with FFmpeg.
Here’s a simple command line that will create 25 PNG images from every second of footage in the input DV file. The images will be saved in the current directory.
ffmpeg -i input.dv -r 25 -f image2 images%05d.png
The newly created files will all start with the word “images” and be numbered consecutively, including five pre-appended zeros. e.g. images000001.png.
From a video that was 104 seconds long, for a random example, this command would create 2600 PNG files! Quite messy in the current directory, so instead use this command to save the files in a sub-directory called extracted_images:
ffmpeg -i input.dv -r 25 -f image2 extracted_images/images%05d.png
Moving on, let’s say you just wanted 25 frames from the first 1 second, then this line will work:
ffmpeg -i input.dv -r 25 -t 00:00:01 -f image2 images%05d.png
The -t flag in FFmpeg specifies the length of time to transcode. This can either be in whole seconds or hh:mm:ss format.
Making things a little more complex we can create images from all frames, beginning at the tenth second, and continuing for 5 seconds, with this line:
ffmpeg -i input.dv -r 25 -ss 00:00:10 -t 00:00:05 -f image2 images%05d.png
The -ss flag is used to denote start position, again in whole seconds or hh:mm:ss format.
Maybe extracting an image from every single frame in a video, resulting in a large number of output files, is not what you need. Here’s how to create a single indicative poster frame, of the video clip, from the first second of footage:
ffmpeg -i input.dv -r 1 -t 00:00:01 -f image2 images%05d.png
Notice that the -r flag is now set to 1.
If you want the poster frame from a different part of the clip, then specify which second to take it from using the -ss tag, in conjunction with the line above.
Lastly, if you wanted to create a thumbnail story board, showing action throughout the entire length of the video clip, you’ll need to specify the output image dimensions. Use the following line:
ffmpeg -i input.dv -r 1 -f image2 -s 120x96 images%05d.png
My original file was 720×576, so the image dimensions are a whole division of this.
Optimised x264 Encoding with FFmpeg
A request on the Ubuntu forums asked for some assistance creating x264 files from footage originating on DVD. The following FFmpeg command represents input from a couple of users regarding what might be the best options:
ffmpeg -y -i input_file -an -v 1 -threads auto -vcodec libx264 -deinterlace -b 5000k -bt 175k -flags +loop -coder ac -refs 1 -loop 1 -deblockalpha 0 -deblockbeta 0 -parti4x4 1 -partp8x8 1 -me epzs -subq 1 -me_range 21 -chroma 1 -slice 2 -bf 3 -b_strategy 1 -level 30 -g 300 -keyint_min 30 -sc_threshold 40 -rc_eq 'blurCplx^(1-qComp)' -qcomp 0.7 -qmax 51 -qdiff 4 -i_qfactor 0.71428572 -maxrate 5000k -bufsize 2M -cmp 1 -s 720x480 -f mp4 -pass 1 /dev/null
ffmpeg -y -i input_file -v 1 -threads auto -vcodec libx264 -deinterlace -b 5000k -bt 175k -flags +loop -coder ac -refs 5 -loop 1 -deblockalpha 0 -deblockbeta 0 -parti4x4 1 -partp8x8 1 -me full -subq 6 -me_range 21 -chroma 1 -slice 2 -bf 3 -b_strategy 1 -level 30 -g 300 -keyint_min 30 -sc_threshold 40 -rc_eq 'blurCplx^(1-qComp)' -qcomp 0.7 -qmax 51 -qdiff 4 -i_qfactor 0.71428572 -maxrate 5000k -bufsize 2M -cmp 1 -s 720x480 -acodec libfaac -ab 256k -ar 48000 -ac 2 -f mp4 -pass 2 new_file.mp4
This command, as an overview does the following:
- Uses libx264 as the output video codec
- Uses libfaac as the output audio codec
- Deinterlaces the original DVD sourced footage
- Allows FFmpeg to choose the number of threads to use for multi-core systems
- Sets the output video bitrate at 5000kbps (or roughly 5Mbps)
- Sets the output audio bitrate at 256kbps
- Deblocks the output footage
- Uses CABAC encoding
- Uses .mp4 as the output file container
- Uses B-Frames
- Uses 2 pass encoding – directing the first output to /dev/null and the second pass to a new file
There are of course many other options included in this command. Further useful reading can be found on the FFmpeg documentation page:
http://ffmpeg.mplayerhq.hu/ffmpeg-doc.html
Also, this Mencoder specific page has some useful information regarding encoding using x264:
FFmpeg Codec Comparison Test – xVid vs x264
Recently I took the time to run a quick comparison test using FFmpeg for producing content with the x264 and xVid codecs. x264 produces H.264 content, while xVid encodes in MPEG4. I was a little surprised with the results.
The input file was sourced from BBC Motion Gallery.
It was an MPEG2 Program Stream with I-Frames, encoded at approximately
50Mbps. It also contained a single MP2 audio track at approximately
356kbps. To see the clip on BBC Motion Gallery, click here.
The clip was chosen because it is only 2 seconds long, so I could
transcode it quickly, and there is also lots of movement, so I expected
artifacts.
The output file container is QuickTime MOV, the video bitrate
around 2Mbps, the audio codec aac (through libfaac) at 128kbps. I
performed a 1 pass and 2 pass encode with x264 and xVid. The output
file was to be 720×404 in size, this is 16:9 aspect ratio. All files
were played back on a Windows XP machine using QuickTime Player 7.1.3.
Some cropping of the original MPEG2 was required to remove VITC at the
top and some black padding left and right. An example FFmpeg command
line I used is outlined below. As you can see, there are very few
optimisations other than the base settings.
FFMPEG command for the second pass x264 encode:
ffmpeg -i 2573-9.mpg -vcodec libx264 -f mov -b 2000k -acodec
libfaac -ab 128k -s 736×442 -croptop 34 -cropbottom 4 -cropleft 8
-cropright 8 -deinterlace -pass 2 2573-9_h264.mov
The final output file sizes are as follows:
- x264 1 pass: 599.558 kilobytes
- x264 2 pass: 553.767 kilobytes
- xVid 1 pass: 577.232 kilobytes
- xVid 2 pass: 559.947 kilobytes
So, while xVid one pass produced smaller file sizes than x264 one
pass, the x264 2 pass file is smaller than the xVid 2 pass file. Due to
the short duration of the input file, no comparison of encoder speed
could really be made. However, anecdotally from other ad hoc encoding
jobs, xVid does seem to be quicker.
Now, to the real proof of the pudding, what was the quality like. Have a look at the following image file, click the thumbnail for a larger version:
This is where I was surprised. The x264 files are on the left. 1
pass is bottom left. 2 pass is top left. The xVid files are on the
right. 1 pass bottom right. 2 pass top right. Clearly, the 1 pass xVid
file is superior to the 1 pass x264 file. I also believe that the 2
pass xVid file is slightly better quality then the 2 pass x264 file.
Areas for close inspection (we’re looking at the two top files here):
- Bottom right corner. There is more blocking and artifacts on the x264 file.
- Top right wing tip. The xVid file has better definition here.
- The underside of the wings and tail. Again the xVid file has better definition.
- The background fire. I think the xVid file has less artifacts and better definition in general.
- As there aren’t a lot of colours in the example video, it’s hard to
say which codec handles colour better, but there is obviously more
depth in each of the 2 pass samples, compared to the 1 pass output.
I was surprised that to my eye the xVid
content appeared to be superior to the x264 output. Perhaps with a more
complext FFmpeg command and options this would have changed.
How-To: Find and Extract Video File Details
Using FFMpeg it is relatively simple to query an existing video file to find details such as video codec, audio codec, bitrates, duration and dimensions.
Use the following FFmpeg command in a terminal window:
ffmpeg -i input_file.extension
FFmpeg will just open your input file without doing anything to it. Something like this will be returned in the terminal window:
phillc@phillc-laptop:~$ ffmpeg -i 848_Termi.mov
FFmpeg version SVN-r11213, Copyright (c) 2000-2007 Fabrice Bellard, et al.
configuration: –enable-gpl –enable-pp –enable-libvorbis
–enable-libtheora –enable-liba52 –enable-libdc1394 –enable-libgsm
–enable-libmp3lame –enable-libfaad –enable-libfaac –enable-libxvid
–enable-pthreads –enable-libx264
libavutil version: 49.6.0
libavcodec version: 51.49.0
libavformat version: 52.2.0
built on Dec 13 2007 20:20:36, gcc: 4.1.3 20070929 (prerelease) (Ubuntu 4.1.2-16ubuntu2)
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from ’848_Termi.mov’:
Duration: 00:00:51.7, start: 0.000000, bitrate: 862 kb/s
Stream #0.0(eng): Video: h264, yuv420p, 480×360 [PAR 0:1 DAR 0:1], 25.00 tb(r)
Stream #0.1(eng): Audio: mpeg4aac, 44100 Hz, stereo
Must supply at least one output file
All very interesting, but what if you want to do something more with this information, like write it to a file for use in another program, or just want a more convenient way of viewing the details without having to remember an FFmpeg command? Write a small script to do the work for you. Here’s one I created earlier in Perl…….
#!/usr/bin/perl
# Read command line input file
$input_file = shift;
# Read details of input file and display to user
$ffmpeg_input_details="ffmpeg -i ${input_file} 2>input_file.txt";
system($ffmpeg_input_details);
open(INPUTFILE,"input_file.txt");
@inputfile = <INPUTFILE>;
@input_file_video = grep (/Video:/i, @inputfile);
@input_file_audio = grep (/Audio:/i, @inputfile);
@input_file_duration = grep (/Duration:/i, @inputfile);
print "Details for the file $input_file.\n";
print "It contains the following video data:\n";
print "@input_file_video\n";
print "It contains the following audio data:\n";
print "@input_file_audio\n";
print "It has a duration and bitrate of:\n";
print "@input_file_duration\n";
To use this script simply type the following at your command prompt:
perl scriptname.pl input_file.extension
Good luck extending this small script for your own uses.
How-To: Install FFMPEG on Ubuntu Gutsy
I wanted to install FFmpeg on my Ubuntu Gutsy
Gibbon (7.10) desktop machine. This is so I can encode and transcode
video files to various formats locally, and also render projects from
the non-linear editor (NLE) PiTiVi.
This post will mainly cover just the commands I used to install FFmpeg on Gutsy, with very little commentary regarding why or how
things work. If you want a more in-depth look at installing FFmpeg, you
can read about the installation
of FFmpeg on my Debian Etch server earlier today – which ultimately
moves me closer to on-the-fly video transcoding of user submitted
content on Kapital Moto TV
Installing FFmpeg on Ubuntu Gutsy:
sudo apt-get build-dep ffmpeg
sudo apt-get install liblame-dev libfaad2-dev libfaac-dev
libxvidcore4-dev liba52-0.7.4 liba52-0.7.4-dev libx264-dev libdts-dev
checkinstall build-essential subversion
svn checkout svn://svn.mplayerhq.hu/ffmpeg/trunk ffmpeg
cd ffmpeg
make distclean (I used this because I already had an older SVN snapshot of FFMPEG downloaded, configured and made from last night)
./configure –enable-gpl –enable-pp
–enable-libvorbis –enable-libtheora –enable-liba52
–enable-libdc1394 –enable-libgsm –enable-libmp3lame –enable-libfaad
–enable-libfaac –enable-libxvid –enable-pthreads –enable-libx264 –enable-shared
make
sudo checkinstall
Some things you might want to do when prompted to by checkinstall:
- Select 0 change maintainer name
- Select 3 to set version name. I used svn11213-ubuntu-gutsy-20071213
And that’s it FFmpeg installed on Ubuntu Gutsy.
Other links:
- Installing FFmpeg on Debian Etch – a far more detailed summary of a very similar process
- FFmpeg User Documentation – where to go next to learn to use FFmpeg
- MPEG4 and H.264 – all about these at the Video Forums.
How-To: Install FFmpeg on Debian Etch
NB: This How-To is now almost totally worthless as it is so out of date. Please click here for an updated version explaining how to install FFmpeg on Debian Squeeze.
–
I have to say, that the video manipulation
program FFmpeg, while very powerful, is not very user-friendly when it
comes to installation. While many Linux programs can be happily
installed from either a pre-compiled package, or downloading source and
compiling yourself, this isn’t necessarily the case with FFmpeg. The
ease of FFmpeg installation largely depends on how many different video
codecs and containers you want to be able to input or output. The
greater the number, the exponential increase in installation
difficulty. My main need was for FFmpeg to accept a wide range of input
formats, while outputting H.264 encoded QuickTime (MOV) files. Here’s
how I achieved this on a Debian Etch server……..
I’m going to assume that you are familiar with using the Linux
command prompt, moving between directories, editing text files and have
at least some experience compiling programs.
The first thing I would recommend doing is making an addition to your source repository lists.
pico /etc/apt/sources.list
Add the following line:
deb http://www.debian-multimedia.org stable main
This repository contains some essential libraries for xvid and
x264 (an open source H.264 codec) amongst other things. You’ll need to
install some software from here. The software may well be available
from other repositories too, that are already in your sources.list
file, but add this one to be safe.
Next rebuild your sources:
apt-get update
I would also recommend installing checkinstall. This program can
be used instead of a regular “make install” command and produces a deb
package file that will make re-installation or multiple machine
installs much easier. If checkinstall isn’t already on your machine
download it from:
http://www.asic-linux.com.mx/~izto/checkinstall/download.php
Maybe navigate here with lynx, maybe use wget once you’ve found
the actual file you need, maybe download it with a GUI based web
browser and then copy it to your desired directory. It’s your choice. I
grabbed the latest .deb package. After the download, execute the following as root:
dpkg -i checkinstall_1.6.1-1_i386.deb
Checkinstall should have happily installed on your system. Now it’s time to really get into FFmpeg.
Build the dependencies:
apt-get build-dep ffmpeg
Next we’re going to install a whole lot more useful software
that will allow FFmpeg to output many more than just the minimal file
types.
apt-get install liblame-dev libfaad-dev libfaac-dev
libxvidcore4-dev liba52-0.7.4 liba52-0.7.4-dev libx264-dev
build-essential subversion,
We’ve also ensured that you have the necessary tools installed
to compile from source (build-essential) and obtain files from the Subversion version control repositories.
We’re ready to checkout FFmpeg itself:
svn checkout svn://svn.mplayerhq.hu/ffmpeg/trunk ffmpeg,
At the time of writing the latest revision was 11212. If you’d
feel more comfortable not using the lastest bleeding edge version of FFmpeg, issue the Subversion command as follows:
svn checkout -r 11212 svn://svn.mplayerhq.hu/ffmpeg/trunk ffmpeg
This will ensure that you are also downloading the 11212 revision. Once downloaded, move into the ffmpeg directory (cd ffmpeg) and configure:
./configure –enable-gpl –enable-pp
–enable-libvorbis –enable-liba52 –enable-libdc1394 –enable-libgsm
–enable-libmp3lame –enable-libfaad –enable-libfaac –enable-pthreads
–enable-libx264 -enable-libxvid –enable-shared
So, what have we done here……
- gpl – allow use of GPL code, the resulting libav* and ffmpeg will be under GPL
- pp – enable GPLed postprocessing support
- libvorbis – enable Vorbis encoding via libvorbis (http://www.vorbis.com/)
- liba52 – enable GPLed liba52 support (http://liba52.sourceforge.net/)
- libdc1394 – enable IIDC-1394 grabbing using libdc1394 and libraw1394 (http://sourceforge.net/projects/libdc1394/)
- libgsm – enable GSM support via libgsm (http://packages.debian.org/testing/sound/libgsm-tools)
- libmp3lame – enable MP3 encoding via libmp3lame (http://lame.sourceforge.net/download.php)
- libfaad – enable FAAD support via libfaad (http://www.audiocoding.com/faad2.html)
- libfaac – enable FAAC support via libfaac (http://www.audiocoding.com/faac.html)
- pthreads – use pthreads (http://en.wikipedia.org/wiki/POSIX_Threads)
- libx264 – enable H.264 encoding via x264 (http://www.videolan.org/developers/x264.html)
- libxvid – enable Xvid encoding via xvidcore, native MPEG-4/Xvid encoder exists (http://www.xvid.org/)
The essence of his information, and many more options, can be found by typing ./configure –help first.
(You might also consider including libtheora in your configuration, but I forgot at the time)
We’re now ready to make the installation files so at the command prompt:
make
If something goes wrong, and you need to start again, a useful command to know is:
make distclean
Make sure you do this first and then run the configure command again.
A finally:
checkinstall
You will be asked a few questions, which should be
straightforward enough to answer – yes to creating the documentation,
choose a name, select D for Debian package, lastly select number 3 and
type a version name that means something to you. Mine was
svn11212-etch-20071213. Checkinstall will now create a Debian package
of FFmpeg, bespoke for your system with the configuration options
you’ve selected earlier. Checkinstall WILL NOT install the package, so
don’t forget to do that:
dpkg -i ffmpeg_svn11212-etch-20071213-1_i386.deb
With some small amount of luck, you should now have a working
version of FFmpeg installed on your Debian Etch server. You will be
able to output H.264 encoded files in a variety of containers.
Now the fun part really begins as you spend days tinkering with
commands to output the best possible files. Documentation for using
FFMPEG can be found at:
http://ffmpeg.mplayerhq.hu/ffmpeg-doc.html
Have fun!
(Credit for getting me started in the right direction goes to Paul Battley and his FFmpeg Ubuntu Feisty install how-to)

After a couple of tips on the FFmpeg user mailing list, I re-ran this test with some command optimisations. Specifically:
New FFMPEG command example for x264, second pass is:
ffmpeg -i 2573-9.mpg -vcodec libx264 -flags +loop -coder ac -f
mov -b 2000k -acodec libfaac -ab 128k -s 736×442 -croptop 34
-cropbottom 4 -cropleft 8 -cropright 8 -deinterlace -pass 2
2537-9_x2642passnew.mov
New screen grab is here, again click for a larger version:
x264 still on the left, xVid on the right. Old 2 pass files
bottom. New 2 pass files, with – coder ac and – flags +loop added to
the FFmpeg command, on top.
The new x264 file is slightly larger than the old one (50 bytes increase). The xVid file is the same size.
From the new screen grab, it can be seen that the x264 output is
now clearly superior. In this case it can be really proved that
optimising the FFmpeg command can truly make a difference.