Veejay HOWTO

Matthijs van Henten ( )
Niels Elburg ( )
v1.0, 30 March 2003
v1.1, 22 June 2003
v1.2, 26 August 2003
v1.3, 9 November 2003

This document describes how to use veejay, a visual 'music' instrument and non linear video editing tool for Linux

1.1 Disclaimer
1.2 Acknowledgements
1.3 Audience and Intent
1.4 Revision History
1.5 New versions of this document
1.6 Feedback
1.7 Distribution Policy
2.About veejay
2.1 Introduction
2.3Hardware configuration
3.1 Dependencies
3.2 Installing veejay
3.3 Installing gveejay
3.4 Streaming video
4.Using Veejay
4.1 Terminology
4.2 The console interface
4.3 The keyboard interface
4.4 Rendering video
4.5 Other utilities
5Popular packages
5.3The MJPEG Tools
6.Other Resources
6.1Web Sites
6.2 Mailing Lists

8.GNU Free Documentation License

1. Introduction

1.1 Disclaimer

No liability for the contents of this documents can be accepted. Use the concepts, examples and other content at your own risk. As this is a new edition of this document, there may be errors and inaccuracies, that may of course be damaging to your system. Proceed with caution, and although this is highly unlikely, the authors do not take any responsibility for that.
All copyrights are held by their respective owners, unless specifically noted otherwise. Use of a term in this document should not be regarded as affecting the validity of any trademark or service mark.
Naming of particular products or brands should not be seen as endorsements.
You are strongly recommended to take a backup of your system before major installation and backups at regular intervals.

1.2 Acknowledgements

The following peope have been helpful in getting this HOWTO done:

1.3 Audience and Intent

This document is targeted at the Linux user interested in learning a bit about veejay and trying it out.

1.4 Revision History

Version 1.0

First version for public release
Version 1.1
Updated Howto to match version 0.4.0. Revised chapters 2.2,4.4, 5.3 and 6
Version 1.2
Updated Howto to match version 0.4.6. Revised chapter 2.1,2.2,3.3
Version 1.3
Updated Howto to match version 0.5.3.

1.5 New versions of this document

You will find the most recent version of this document at
If you make a translation of this document into another langauge, let us know and we'll include a reference to it here.

1.6 Feedback

We rely on you, the reader, to make this HOWTO usefull. If you have any suggestions, corrections , or comments , please send them to us ( ), and we will try to incorporate them in the next revision. Please add 'HOWTO veejay' to the Subject-line of the mail.
Before sending bug reports or questions, please read all of the information in this HOWTO, and send detailed information about the problem.
If you publish this document on a CD-ROM or in hardcopy form, a complimentary copy would be appreciated. Mail us for our postal address. Also consider making a donation to the Veejay Project to help support free video editing software in the future.

1.7 Distribution Policy

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts , and with no Back-Cover Texts. A copy of this license is included in the section entitled "GNU Free Documentation License".

2. About Veejay

Veejay is a video tracker/editing and live performance tool for Linux. It provides a graphical interface for video editing and mixing as well as a keyboard interface for direct user interaction (in a performance environment).

2.1 Introduction

Veejay is a small collection of utilities build arround veejay, it has an optional graphical interface gveejay which provides (remote) non linear editing. Veejay provides sample based editing and will provide tracker style compositing of video in the future. Sample based editing means dividing your video material into short loops and then to process them individually by setting up properties or adding effects/transitions on the sample's effect chain. All these actions can be applied in realtime, showing immediate effect on your video. It provides mechanisms to mix multiple video sources in realtime.

2.2 Features


  • Free Software (GNU GPL)
  • TCP/IP support for media and content control
  • Open Sound Control
  • Realtime video mixing from multiple video sources
  • XML formatted Sample Lists
  • OSS audio
  • SDL and/or DirectFB
  • Man pages


  • MJPEG (Quicktime/Movtar or AVI)
  • DV avi type 2 (PAL or NTSC)
  • YUV4MPEG streams
  • RGB24 streams
  • Video4Linux support (only Input)
  • vloopback support


  • Sample based
  • Non descructive
  • Over 40 different types of blending
  • Chroma / Luma keying
  • 76 effects/transitions
  • No undo/redo
  • Frame accurate navigation/editing
  • Cut/Copy/Paste/Crop/Delete video


  • Remote (over TCP/IP)
  • Console
  • SDL Keybindings
  • OSC (over UDP)
  • Gestural Interface (camera)

2.3 Hardware configuration

Veejay requires at least a linux kernel 2.4.x or later, a lot of diskspace and a fast CPU. Depending on the speed of your machine, your milage may vary. See the list below for a few systems veejay was reported to work on:

  • A dual celeron 400 Mhz/512 MB RAM with a voodoo3 and second pci card.
  • An Athlon 750 Mhz with voodoo3 and second pci card.
  • An Athlon 750 Mhz with Matrox G400 Dualhead(TVout using X11/SDL or DirectFB)
  • An Athlon 850 Mhz and Matrox G550 Dualhead( TVout support through DirectFB)
  • An Athlon XP 1600 Mhz and Matrox G550 Dualhead( TVout support through DirectFB)
  • A Pentium 4 2.2 Ghz and Matrox G550 Dualhead( TVout support through DirectFB)

Video Editing requires a lot of diskspace, make sure you you have enough diskspace available for your project. You need at least twice as much diskspace available as the size of your captured video, veejay does not write to your original video files unless you specify it to overwrite.

3. Installation

3.1 Dependencies

Before you install Veejay, make sure you have the following dependencies installed:

  • libdv >= 0.99
  • The SDL library >= 1.2.3
  • GTK >= 1.2
  • The XML C library 2 for gnome >=2.5.4
  • NASM
  • DirectFB support for Matrox Tv-Out >= 0.9.17

On newer distributions, most of the listed software should already have been installed.
You can find the websites of these projects in Other Resources.

3.2 Installing veejay

After downloading the source package , decompress and untar the file by typing:

$ tar -zxvf veejay-0.5.x.tar.gz
Change to the directory containing veejay's source's:
$ cd veejay-0.5.x
First, you have to compile FFmpeg's avcodec which is included in the package;
$ cd ffmpeg
$ ./configure
$ make
FFmpeg is included in the source distribution to avoid version problems.
After you have compiled FFmpeg succesfully, go back to the top level directory of the pacakge and do:
$ ./configure
On completion it will summarize the results of the ./configure script

veejay 0.4.6 build configuration :

   - X86 Optimizations:
     - MMX/3DNow!/SSE enabled      : true
     - Using fast memcpy           : true
     - cmov support enabled        : true
  * NOTE:                                                               *
  *   The resultant binaries will ***NOT*** run on a K6 or Pentium CPU  *
   - video4linux recording/playback  : true
   - software MJPEG playback         : true
   - XML C library for Gnome libxml2 : true
   - movtar playback/recording       : false
   - Quicktime playback/recording    : false
   - DirectFB support	            : true (>= v0.9.17)
   - libDV (digital video) support : true (>= v0.9.5)
   - glibc support for >2GB files  : true

If the lists includes everything you need type
$ make
Followed by
# make install

3.3 Installing gveejay

After downloading the source package 'gveejay' , decompress and untar the file by typing:

$ tar -zxvf gveejay-0.4.x.tar.gz
Change to the directory containing veejay's source's:
$ cd gveejay-0.4.x
Now, run the configure script and build gveejay:
$ ./configure 
$ make
And install it by typying:
$ make install

3.4 Streaming video

First of all, you need to have Video For Linux enabled in your kernel configuration. Make sure that V4L information in proc filesystem is enabled; veejay uses the proc file system to find out what vloopback output can be used to read from from.

If you have no Video4Linux devices you can only stream from vloopback or from a yuv4mpeg stream. You still need to have the above mentioned items if you want to use vloopback.

If you have one or more Video4Linux devices, you should load these devices prior to loading the vloopback module. The example below loads the vloopback module with a device offset parameter so it will not conflict with your Video4Linux devices:

# insmod vloopback.o pipes=4 dev_offset=2
On typing the command
# dmesg
you should see something like this:
Mar 31 23:41:01 dev kernel: vloopback.c: Video4linux loopback driver v0.90
Mar 31 23:41:01 dev kernel: vloopback.c: Loopback 0 registered, input: video2, output: video3
Mar 31 23:41:01 dev kernel: vloopback.c: Loopback 1 registered, input: video4, output: video5
Mar 31 23:41:01 dev kernel: vloopback.c: Loopback 2 registered, input: video6, output: video7
Mar 31 23:41:01 dev kernel: vloopback.c: Loopback 3 registered, input: video8, output: video9
Refer to chapter 5. Popular Packages for using a video source.

4. Using Veejay

Veejay uses by default a SDL window to play a video file or video stream, all the keybinding in veejay depend on SDL; if you move your mouse over to the SDL windows to focus it , you can press the keys explained in 4.3 The keyboard interface.
On focussing the terminal in which veejay is running, you can type short commands (followed by a Return or Enter) for saving / loading samplelists , to activate other video sources and much more, see 4.2 The console interface.
You must provide a video file to use with veejay; it will not run without a video file.

4.1 Terminology

Veejay has a number of playback modes, each playback mode is unique and defines more or less a different functionality:

Playback modes in veejay

Mode Description Navigation Looping Speed Effect Chain
Plain Default mode, playback of video Yes No Yes No
Sample Sample mode, playback of video samples. Yes Yes Yes Yes
Tag Tag mode, playback of video streams No No No Yes

4.2 The console interface

The console interface takes commands from STDIN , the commands you can give apply to:

  • Editlists
  • Samples
  • Streams

Commonly used console commands

Description Examples
Load a samplelist from file sl /tmp/my_samplelist
Save a samplelist to a file ss /tmp/new_samplelist
Open a video4linux device for input vi /dev/video0
Open a vloopback pipe for input li 0
Open a yuv4mpeg stream to dump video ft
Close the yuv4mpeg stream ft
Open a vloopback pipe to stream out lo 1
Close a vloopback device that is streaming out lc

The complete list of all console commands can be found in the Man pages, you can access the Man page by typing:
$ man veejay

4.3 The keyboard interface

The keyboard interface takes keypresses (events) from SDL, almost all keys on your keyboard have a function in veejay.

Typically, the keys on your numeric keypad can be used for navigation (play forward, play backward, skip frames, skip to end , skip to start , etc).

The keys a,s,d,f, g,h,j,k and l can be used to increase speed from 1 (normal) to 9 (fast)

Here is a quick overview for the most commonly used keys, if applied in order you will end up with a newly created video sample looping in some way (depending on how many times you press the asterix key)

Commonly used keyboard bindings

Description SDL key In plain english
Set the starting position of a new sample SDLK_LEFTBRACKET Left bracket
Set ending position and create a new sample SDLK_RIGHTBRACKET Right bracket
Select and play sample 1 SDLK_F1 F1
Set playback speed to 3 SDLK_d d
Change looptype SDLK_KP_MULTIPLY asterix on numeric keypad
Play backward SDLK_KP_4 Cursor left on numeric keypad
Play forward SDLK_KP_6 Cursor right on numeric keypad
Skip 1 second SDLK_KP_8 Cursor up on numeric keypad
Switch playmode to Plain SDLK_KP_DIVIDE Divide on numeric keypad
Print information about sample SDLK_HOME Home

The function keys F1...F12 can be used to select sample 1 ... 12, use the keys 1...9 to select a sample range 1-12 ... 108-120 and press one of the F-keys to play that sample.

Use ESC to switch between samples and tags, as samples and tags are closely related, you can use the function keys to select Tags when playing in this mode. Press ESC to switch back to the sample playmode
You can create Tags using the console interface; a new Tag will use the first available entry so the first Tag you create can be played by pressing the F1 key. By default the stream is not active; you will see a red screen. Press Insert to toggle the stream on or off.

A complete overview of all keyboard bindings can be found in the Man page of veejay, access it by typing:
$ man veejay

4.4 Rendering video

You can output video to a yuv4mpeg stream by using the ft console command or by using the Grab Video button in gveejay.
veejay will automatically create a new file when you toggle the output stream
It is possible to start veejay headless and have it write all video data to a (special) file for further processing.

Refer to chapter 5.3 for some examples.

4.5 Other utilities

Currently there are 2 extra utilities yuv2rawdv and rawdv2yuv included in the veejay package for encoding a Y'CBCR 4:2:0 stream to raw DV and vice versa.

yuv2rawdv takes input from STDIN and outputs to STDOUT, we illustrate this with a few examples.

When loading yuv2raw dv without parameters you will see:

This program reads a YUV4MPEG stream and puts RAW DV to stdout
Usage:  yuv2rawdv [params]
where possible params are:
    -v num    Verbosity [0..2] (default 1)
    -l num    Clamp Luma (default 0)
    -c num    Clamp Chroma (default 0)
If you use the clamp parameters, it will clip (not scale!) a pixel into a valid range, the resulting video could be for example a bit darker if the input stream has values for Luminance exceeding the maximum of 235.
See the table below for all valid ranges.


Channel Range (Clamp) Byte range (no clamping)
Y (Luminance) 16 - 235 0 - 255
Cb (Chroma Blue) 16 - 240 0 - 255
Cr (Chroma Red) 16 - 240 0 - 255

To convert a yuv4mpeg file to rawdv (the yuv4mpeg file needs to be compatible with the digital video format properties)
$ cat yuv4mpeg-file.yuv | yuv2rawdv | playdv

To convert a yuv4mpeg file to rawdv with luminance and chroma information clipped to a valid range:
$ cat yuv4mpeg-file.yuv | yuv2rawdv -l 1 -c 1 | playdv

rawdv2yuv takes input from STDIN and outputs to STDOUT, we illustrate this with a few examples.
This program reads a raw DV stream from stdin and puts YV12/I420 to stdout
Usage:  rawdv2yuv [params]
where possible params are:
   -v num     Verbosity [0..2] (default 1)
   -x         Swap Cb/Cr channels to produce IV12 (default is I420)
   -n num     Norm to use: 0 = NTSC, 1 = PAL (default 1)
   -q         DV quality to fastest (Monochrome)
   -h         Output Half frame size
   -c num     clip off  rows of frame (for use with -h)
              must be a multiple of 8

If you want to convert a full PAL/NTSC dv frame to half PAL YCbCr (I420 or YV12) you can give the command:
$ cat raw.dv | rawdv2yuv -h | yuvplay

You can use the -c parameter to clip the width of the video frame.
$ cat raw.dv | rawdv2yuv -h -c 8 | yuvplay

The resizer in rawdv2yuv uses a best neighbour interpolation algorithm for downsizing.

5 Popular Packages

Usefull software (in no apparant order):

  • EffecTV
  • Mplayer
  • The MJPEG Tools
  • Transcode
  • Motion
Please refer to Other Resources to find the project's website

5.1 EffecTV

EffecTV is a real-time video effector. You can watch TV or video through amazing effectors, it supports output and input from a vloopback device, enabling you to create multiple video pipelines to veejay for further processing.

Starting effectv to read from your video4linux device and output to veejay:
$ effectv -device /dev/video0 -channel 1 -norm pal -vloopback /dev/video2
If everything goes well you should see your camera input in EffecTV; continue loading veejay:
$ veejay -a0 -v2 /tmp/my_video_file.avi
Type the command li in the veejay's console, hit ESC and press Insert to toggle the stream on or off.
If you want to use veejay's output in EffecTV you can start veejay by:
$ veejay -a0 -v2 /tmp/my_video_file.avi -vloopback /dev/video2
If everything goes well you see your video file beeing played back. Type the command lo to start streaming to the vloopback device, continue starting EffecTV by typing:
effectv -device /dev/video3 -norm pal -size 352x288
If everything goes well you see veejay's output in EffecTV.

5.2 mplayer

Mplayer is the movie player for linux, it has support for different types of output You can use mplayer to play a DVD or some MPEG4 file and stream it into veejay. First, create a named pipe

$ mkfifo stream.yuv
Continue with starting mplayer
$ mplayer -vo yuv4mpeg -ao null -zoom -x 352 -y 288 -vop scale yuy2 /tmp/mpeg4_movie.avi
If everything goes well, mplayer waits until a frame has been read from the named pipe. Mplayer uses by default the filename stream.yuv, if you specify another mplayer will create a stream.yuv.
Start veejay as usual and type the command fi stream.yuv, hit ESC and press Insert to toggle the stream on/off.

5.3 The MJPEG Tools

The Mjpeg tools are a set of tools that can do recording of videos and playback, simple cut-and-paste editing and the MPEG compression of audio and video under Linux. You can use the EditLists from this package in veejay.
Here are a few examples for processing video data:

1. Start veejay headless:

$ mkfifo /tmp/special_file
$ veejay /video/video.avi -O3 -o /tmp/special_file

Encoding it to DV avi type 2 (if video dimensions match either full PAL or NTSC)
$ cat /tmp/special_file | yuv2rawdv -v 2 > rawdv

Encoding it to MJPEG file 'video-mjpeg.avi'
$ cat /tmp/special_file | yuv2lav -v2 -f 0 -I 0 -q 90 -o video-mjpeg.avi

5.4 Transcode

Transcode is a Linux video Stream Processing Tool, it can convert between different types of video formats

Encode a file to mjpeg with no audio and rescale the output video to 352x288:

$ transcode -i input_file.avi -o new_mjpeg_file.avi -y mjpeg,null -Z352x288

6. Other Resources

Here you will find the websites of the packages veejay requires as well as packages you can use in combination with veejay.

6.1 Web Sites

Packages you need

Usefull software

6.2 Mailing Lists

There is a mailing list for veejay which is hosted by Sourceforge. The address is

7. Credits

End of the Veejay HOWTO. (You can stop reading here.)

8. GNU Free Documentation License

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You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.

You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.


A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, does not as a whole count as a Modified Version of the Document, provided no compilation copyright is claimed for the compilation. Such a compilation is called an "aggregate", and this License does not apply to the other self-contained works thus compiled with the Document, on account of their being thus compiled, if they are not themselves derivative works of the Document.

If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one quarter of the entire aggregate, the Document's Cover Texts may be placed on covers that surround only the Document within the aggregate. Otherwise they must appear on covers around the whole aggregate.


Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License provided that you also include the original English version of this License. In case of a disagreement between the translation and the original English version of this License, the original English version will prevail.


You may not copy, modify, sublicense, or distribute the Document except as expressly provided for under this License. Any other attempt to copy, modify, sublicense or distribute the Document is void, and will automatically terminate your rights under this License. However, parties who have received copies, or rights, from you under this License will not have their licenses terminated so long as such parties remain in full compliance.


The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See

Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License "or any later version" applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation.

ADDENDUM: How to use this License for your documents

To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:

    Copyright (c)  YEAR  YOUR NAME.
    Permission is granted to copy, distribute and/or modify this document
    under the terms of the GNU Free Documentation License, Version 1.1
    or any later version published by the Free Software Foundation;
    with the Invariant Sections being LIST THEIR TITLES, with the
    Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.
    A copy of the license is included in the section entitled "GNU
    Free Documentation License".

If you have no Invariant Sections, write "with no Invariant Sections" instead of saying which ones are invariant. If you have no Front-Cover Texts, write "no Front-Cover Texts" instead of "Front-Cover Texts being LIST"; likewise for Back-Cover Texts.

If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.