vnc2flv

Desktop Screen Recorder for UNIX, Linux, Windows or Mac.

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Last Modified: Mon Aug 24 11:11:59 JST 2009

What's It?

Vnc2flv is a cross-platform screen recording tool for UNIX, Windows or Mac. It captures a VNC desktop session (either your own screen or a remote computer) and saves as a Flash Video (FLV) file.

(Vnc2flv is a rewrite of its predecessor, vnc2swf. As FLV format is more prevalent today, vnc2flv is specialized for FLV format and aims at a simpler and more lightweight functionality.)

Demo: (recorded with vnc2flv itself)
http://www.youtube.com/watch?v=DcijI6EagYI

Download:
http://www.unixuser.org/~euske/python/vnc2flv/vnc2flv-20090824.tar.gz

Questions and Comments: (post here!)
http://groups.google.com/group/vnc2flv-users/

How to Install

  1. First of all, you need to have a VNC server running on your computer (or a remote machine you want to capture).
  2. You need Python 2.4 or newer.
  3. Download and extract the vnc2flv source distribution.
  4. Run setup.py to install:
    # python setup.py install
  5. Done!

How to Use

vnc2flv comes with three programs:

flvrec.py

flvrec.py is the main recording program. It connects to a specified VNC server and immediately starts recording. It stops when it receives a SIGINT (or Ctrl-C is pressed). You need to have a VNC server running on the target machine in advance.

The recorded file is playable via either desktop programs like ffmpeg, VLC or mplayer, or other online Flash-based players.

Syntax:

flvrec.py [options] [host[:port]]

Examples:

$ x11vnc -quiet -localhost -viewonly -nopw -bg
(start up a vnc server)

The VNC desktop is:      localhost:0
PORT=5900

******************************************************************************
Have you tried the x11vnc '-ncache' VNC client-side pixel caching feature yet?

The scheme stores pixel data offscreen on the VNC viewer side for faster
retrieval.  It should work with any VNC viewer.  Try it by running:

    x11vnc -ncache 10 ...

more info: http://www.karlrunge.com/x11vnc/#faq-client-caching

$ flvrec.py localhost:5900
(Record a local desktop)

$ flvrec.py -C 640x480+0-0 remotehost:5900
(Record a remote desktop with a 640x480 window at the bottom left of the screen.)

$ flvrec.py -S 'arecord -f cd $BASENAME.wav'
(Record a local desktop and capture audio input simultaneously using the ALSA recording utility)

Options:

-o filename
Specifies the output file name. By default, the output file is given with a unique name.
-r fps
Specifies the number of frames per second. (default: 15)
-K keyframe
Specifies the rate of key frames that is inserted in every this number of frames. (default: every 150 frames)
-P pwdfile
Specifies the password file for a vnc session.
-N
Suppress the appearance of mouse pointer in the video.
-e encoding,encoding,...
Specifies the vnc encoding methods. (default: raw)
-B blocksize
Specifies the block size. (default: 32)
-C wxh{+|-}x{+|-}y
Specifies the clipping. (default: entire screen)
-S commandline
Starts a child process immediately after the recording is started. When the recording is stopped, a SIGINT is sent to the subprocess. The basename of the movie that is being recorded is passed to $BASENAME environment variable.
-d
Increases the debug level.

flvcat.py

flvcat.py is a simplistic editing program for a FLV movie. It supports concatenating multiple movies, clipping a movie's frame size, re-sampling a movie into a smaller size with auto-panning, etc.

Syntax:

flvcat.py [options] src1[:ranges1] src2[:ranges2] ... output

For each movie file, you can clip the parts of the movie to add by specifying its ranges. Ranges is comma-separated, hyphenated list of milliseconds. For example,

out.flv:10000-20000
means a 10-second clip from movie out.flv (0:10-0:20). Specifying only one end of the range is also supported:
out.flv:10000-
means the entire movie except the first 10 seconds. When ranges are omitted, the whole movie is used.

Examples:

$ flvcat.py movie1.flv movie2.flv output.flv
(Concatenate movie1.flv and movie2.flv and save it as output.flv)

$ flvcat.py -W 640x480 movie1.flv output.flv
(Resize the movie1.flv with auto-panning with its window size 640x480 and save it as output.flv)

$ flvcat.py movie1.flv:15000-30000 output.flv
(Clip the part of movie1.flv from 0:15 to 0:30 and save it as output.flv)

$ flvcat.py movie1.flv:2500- output.flv
(Chop the first 2.5 seconds off and save it as output.flv)

Options:

-r fps
Specifies the number of frames per second. (default: 15)
-K keyframe
Specifies the rate of key frames that is inserted in every this number of frames. (default: every 150 frames)
-B blocksize
Specifies the block size. (default: 32)
-C wxh{+|-}x{+|-}y
Specifies the clipping. (default: entire frame)
-W wxh
Specifies the window size for auto panning. Auto panning tracks the changes in the screen and tries to focus on the active part of the screen. This helps reducing the movie screen size. (default: no auto panning)
-S speed
Specifies the speed of auto panning. (default: 60 frames)
-f
Forces overwriting the output file.

flvaddmp3.py

Add mp3 audio files to a movie.

Syntax:

flvaddmp3.py [options] src mp3file1[:ranges] mp3file2[:ranges] ... output

Options:

-f
Forces overwriting the output file.

flvdump.py (for debugging)

This program dumps the contents of a FLV file. This is used solely for debugging purposes.

Syntax:

flvdump.py [options] flvfile

Adding Audio

flvrec.py can designate a child process to record audio during recording. By giving -S option, the specified command line is executed when the recording is started. The child process can capture audio input and encode it as an appropriate format. The process is terminated when the recording is stopped. To put it onto an FLV movie, the audio needs to be encoded as MP3 format. After the recording is finished, the user can use the flvaddmp3.py command to combine the movie and audio output.

1. Record the screen and audio simultaneously:

$ flvrec.py -S 'arecord -f cd $BASENAME.wav'

2. Convert the WAV file into MP3:

$ lame out200908122312.wav out200908122312.mp3

3. Add the MP3 file to the movie:

$ flvaddmp3 out200908122312.flv out200908122312.mp3 final.flv

Changes

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Terms and Conditions

Copyright (c) 2009 Yusuke Shinyama <yusuke at cs dot nyu dot edu>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Yusuke Shinyama