VideoLAN Wiki - User contributions [en]

VLC HowTo/Transcode multiple videos

2008-09-28T02:14:50Z

Fenugrec: vlc://quit ref

== Idea ==
The idea is to use VLC to do some batch work to encode or transcode multiple files one after each other, without having to care about it.

You may want to transcode all your videotheque to another format to play them on an [[IPod]], a [[Play on Zune|Zune]], a PS3 or a [[Play on Xbox|Xbox]].

== Codecs / Muxers ==

You have to choose the correct codecs for the device you want to transcode for.

We choose here [[H.264]] with [[AAC]] in a [[MPEG-2#TS|MPEG-2/TS]] muxer as an example.

== Command Lines ==

=== Windows ===

for %%a in (*.VOB) do "C:\Program Files\VideoLAN\VLC\vlc" -I dummy -vvv %%a --sout=#transcode{vcodec=h264,vb=1024,acodec=mp4a,ab=192,channels=2,deinterlace}:standard{access=file,mux=ts,dst=%%a.mpg} vlc://quit

For example, to transcode a batch of m4a files (potentially in multiple subdirectories of a single common root directory) to mp3 files (512kb/s encoding with 44100 sampling frequency) you could use the following code in a Windows XP command prompt:
@ECHO OFF
REM ########################################################################
REM # A Windows XP cmd.com script to batch convert m4a files to mp3. #
REM # #
REM # Copyright (C) 2008 Andrew Boden #
REM # (boden@graduate.uwa.edu.au) #
REM # #
REM # This program is free software: you can redistribute it and/or modify #
REM # it under the terms of the GNU General Public License as published by #
REM # the Free Software Foundation, either version 3 of the License, or #
REM # (at your option) any later version. #
REM # #
REM # This program is distributed in the hope that it will be useful, #
REM # but WITHOUT ANY WARRANTY; without even the implied warranty of #
REM # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the #
REM # GNU General Public License for more details. #
REM # #
REM # You should have received a copy of the GNU General Public License #
REM # along with this program. If not, see <http://www.gnu.org/licenses/>.#
REM # #
REM # Version 1.0 (June 27th 2008) #
REM # Uses VideoLAN VLC 0.8.6h (www.videolan.org) #
REM # Gracefully handles commas and apostrophes in file names. #
REM # Not aware of any other characters needing graceful handling. #
REM # 512kbps encoding with 44100 sampling. #
REM ########################################################################

FOR /R %%G IN (*.m4a) DO (CALL :SUB_VLC "%%G")
FOR /R %%G IN (*.m4a.mp*) DO (CALL :SUB_RENAME "%%G")
GOTO :eof

:SUB_VLC
SET _firstbit=%1
SET _qt="
CALL SET _newnm=%%_firstbit:%_qt%=%%
SET _commanm=%_newnm:,=_COMMA_%
REM echo %_commanm%
CALL "C:\Program Files\VideoLAN\VLC\vlc" -I dummy -vvv %1 --sout=#transcode{acodec="mpga",ab="512","channels=2",samplerate="44100"}:standard{access="file",mux="mpeg1",dst="%_commanm%.mp3"} vlc:quit
GOTO :eof

:SUB_RENAME
SET _origfnm=%1
SET _endbit=%_origfnm:*.m4a=%
CALL SET _newfilenm=%%_origfnm:.m4a%_endbit%=.mp3%%
SET _newfilenm=%_newfilenm:_COMMA_=,%
COPY %1 %_newfilenm%
DEL %1
GOTO :eof

:eof

The same as above, for vlc >= 0.9:
@ECHO OFF
FOR /R %%G IN (*.m4a) DO (CALL :SUB_VLC "%%G")
FOR /R %%G IN (*.m4a.mp*) DO (CALL :SUB_RENAME "%%G")
GOTO :eof

:SUB_VLC
SET _firstbit=%1
SET _qt="
CALL SET _newnm=%%_firstbit:%_qt%=%%
SET _commanm=%_newnm:,=_COMMA_%
REM echo %_commanm%
CALL "C:\Program Files\VideoLAN\VLC\vlc" -I dummy -vvv %1 --sout=#transcode{acodec="mp3",ab="512","channels=2"}:standard{access="file",mux="raw",dst="%_commanm%.mp3"} vlc://quit
GOTO :eof

:SUB_RENAME
SET _origfnm=%1
SET _endbit=%_origfnm:*.m4a=%
CALL SET _newfilenm=%%_origfnm:.m4a%_endbit%=.mp3%%
SET _newfilenm=%_newfilenm:_COMMA_=,%
COPY %1 %_newfilenm%
DEL %1
GOTO :eof

:eof

=== Unix / Linux ===

vcodec="h264"
acodec="mp4a"
bitrate="1024"
arate="192"
ext="mpg"
mux="ts"
vlc="/usr/bin/vlc"
fmt="VOB"
dst="/home/user/"

for a in *$fmt; do
$vlc -I dummy -vvv "./$a" --sout "#transcode{vcodec=$vcodec,vb=$bitrate,acodec=$acodec,ab=$arate,channels=6}:standard{mux=$mux,dst=\"$dst$a.$ext\",access=file}" vlc://quit
done

Uncommon uses

2008-09-28T01:47:10Z

Fenugrec: vlc://quit ref

The modular nature of {{VLC}} allows you to do quite strange and unusual things with it. This page tries to list some funny and insane uses.

== Caca and Goom ==

If you have vlc compiled with both caca and goom you can listen to music with [[caca]] rendering the output of [[goom]]. That means you can show the visualisations from an audio file as colour ASCII art! Try something like this:
vlc --audio-filter goom --vout caca somemusic.mp3

Likewise, if you would like to view a video file as colour ASCII art, try the following:
vlc --vout caca somevideo.avi

== Pipe data to VLC ==

You can pipe input from standard input to VLC, rather than open a file or stream. VLC accepts data this way if you use a dash as a filename, ie:
vlc -
Piping passes the output of one program into the input of another. An example of this is using [[wikipedia:Cat (Unix)|cat]], which is part of GNU coreutils (ie, on *nix systems). Cat displays the contents of a file to standard output (normally to the screen as text). In this case, we'll use the pipe character to redirect this into vlc's standard input, whch will then be played. To wit,
cat file.mpg | vlc -

All very sane (though pointless) so far: if you're looking for madness, read on. You can get input from anywhere. A good place to get input is [[ffmpeg]]. Say you have a [[wikipedia:.flv|.flv]] file (which VLC now supports from version 0.8.4a onwards) and you want to play it in vlc. You could use ffmpeg to transcode it on the fly and pipe the output to vlc. The following command will do this:
ffmpeg -i 0.flv -f asf - | vlc -
A longer version with all the options ffmpeg likes to have is:
ffmpeg -i 0.flv -vcodec mpeg4 -ac 1 -ab 64 -acodec mp2 -b 128 -f asf -s cif - | vlc -
The advantage of this is that you don't have to make a new file (possibly 100s of MB in size). But you'll probably need a good computer. Plus, you wont have much control when playing it. You can pipe into ffmpeg too, so I suppose you could pass things along ffmpeg forever, transcoding it a million different ways, and ending up in vlc (please don't try that, your computer really wouldn't like it).

== Encoding Lots of Files ==

This command shows how to encode a whole directory of files in Linux, without your input. When complete, it'll show a message to say it is complete. It's a single command split over several lines (with \)

for A in *.avi; do \
echo ************************* $A ********************* ;\
vlc --sout-all "$A" :sout="#transcode{...}:\
std{access=file,mux=avi,url=~/$A.avi}" \
vlc://quit -I dummy ;\
done ;\
Xdialog --title 'Complete' --msgbox 'All done' 0 0;

Make sure you really understand this command before using it. It's also a good idea to make sure you've got the right options in the transcode bit, and that it'll transcode the right files. The output is sent to your home folder in this example.

[[Category:How_To]]

VLC HowTo/Shut down the computer at the end of the playlist

2008-09-28T01:45:48Z

Fenugrec: vlc://quit ref

{{howto|Switch off your computer automatically, when VLC has finished playing a file}}

= General idea =
It is not a feature included in {{VLC}} but small scripts can do it for you.

= Quit VLC =

You can quit {{VLC}} after playback is finished, by adding
<pre>vlc://quit</pre> to the playlist.

= Shutdown =

== Windows ==

Make a .bat file. The first command would be launching VLC, the second one is
<pre>SHUTDOWN -s -t 01</pre>.
Add vlc://quit to leave.

Launch {{VLC}} through the shortcut to the bat file.

== Linux ==
Make a .sh.
<pre>
#! /bin/sh

vlc && shutdown -h now
</pre>

Transcode

2008-09-28T01:42:47Z

Fenugrec: vlc://quit references

Transcoding is the process of taking a video file and changing it to a different format or bitrate.

Transcoding in VLC copies the movie to a new file in a different format, so you end up with both the original and new files. This means you need to have enough space on your hard drive to store this extra file. You should also have a reasonably fast computer, as transcoding can be very slow.

In VLC, transcoding is exactly the same as [[streaming]] accross a network, except that the output is sent to a file instead of a network.

== Transcoding with the Wizard ==

VLC includes a transcoding and streaming wizard. To transcode a file, just select the transcode option. You will then be asked what format to convert to: you can give a video [[codec]], an audio codec and a [[container]] format. Only some container formats can support some codecs - look [http://www.videolan.org/streaming/features.html here] to see what supports what.

{{doc|http://www.videolan.org/doc/streaming-howto/en/ch02.html}}

== Transcoding with the Command Prompt ==

The most flexible way to transcode with vlc is using a [[command prompt]] to start vlc. Transcoding works the same as [[streaming]]. For example, the following command changes an [[asf]] file to an [[MPEG-2]] file:
:vlc "C:\Movies\Your File.asf" :sout='#transcode{vcodec=mp2v,vb=4096,acodec=mp2a,ab=192,scale=1,channels=2,deinterlace,audio-sync}:std{access=file, mux=ps,url="C:\Movies\Your File Output.ps.mpg"}'
The access=file instructs vlc to store the output in a file (and not stream it), and the url is the location of the new (output) file.

(Note: If you are running VLC on [[Mac OS X]], you should use clivlc instead of VLC to avoid possible Bus error problems.)

Transcoding takes quite a while, so it's advisable to use an option like '''--stop-time=30''' to only encode the first 30 seconds - this means you can check the file has transcoded correctly, and that the output is of a suitable quality. (Note: On [[Mac OS X]] this trick doesn't seem to work. Just press ctrl-c after a while, VLC will properly write out the already transcoded segment)

The transcode statement can contain '''vcodec''' and '''vb''' to change the video codec and '''acodec''' and '''ab''' to change the audio codec. If vcodec is missing, the video codec will stay the same (same for acodec).

Common additional options to use are '''audio-sync''' (to make sure the audio is in sync correctly) and '''deinterlace''' (to increase quality slightly on interlaced video).
===Under MS Windows===
the syntax on windows is slightly different:

C:\Program Files\VideoLAN\VLC>vlc -vvv "D:\688497.flv" --sout=#transcode{vcodec=
mp4v,acodec=mpga,vb=800,ab=128,deinterlace}:standard{access=file,mux=ts,url="D:\
asd.mpg"}

===Completely non-interactive transcoding===
For completely non-interactive transcoding (such as the case necessary when running under [[Mac OS X]]), the above example could be rewritten as
:vlc -I dummy "C:\Movies\Your File.asf" :sout='#transcode{vcodec=mp2v,vb=4096,acodec=mp2a,ab=192,scale=1,channels=2,deinterlace,audio-sync}:std{access=file, mux=ps,url="C:\Movies\Your File Output.ps.mpg"}' vlc://quit
The two extra options are
;-I dummy: Disables the graphical interface
;<nowiki>vlc://quit</nowiki>: Quit VLC after transcoding
If transcoding from a DVD, it is also necessary to use the dvdsimple:// notation instead of the dvd:// notation, in order to avoid interacting with the DVD menu system (which is quite impossible without the graphical interface).

{{doc|http://www.videolan.org/doc/streaming-howto/en/ch03.html}}

== Non-Interactive Batch Transcoding (Windows)==
To transcode several files without user interaction create a batch file in the folder where the files are contained and this line to the batch file:

<pre>
for %%a in (*.FILE_EXT) do cmd /c "PATH_TO_VLC" -I dummy -vvv %%a --sout=#transcode{vcodec=VIDEO_CODEC,vb=VIDEO_BITRATE,scale=1,acodec=AUDIO_CODEC,ab=AUDIO_BITRATE,channels=6}:standard{access=file,mux=MUXER,dst=%%a.OUTPUT_EXT} vlc://quit
</pre>

Cmd /c makes the script wait to finish transcoding before starting the next transcode.

An alternative method is to use VB Script. This example will transcode all files from one folder to another. It will also wait for each file to finish transcoding before starting the next. Create the script transcode.vbs, in the VLC installation folder, default "C:\Program Files\VideoLAN\VLC". Change the strSource and strTarget in the example to match your requirements. Start a "DOS Box", Start - Run - cmd then change to the VLC folder and run the script "cscript transcode.vbs".

This example was tested on Microsoft Windows Script host 5.6 running on XP Pro SP2

<pre>
'
' based on code from:http://episteme.arstechnica.com/eve/forums/a/tpc/f/12009443/m/516001349831
'
'
'
Dim objFSO, objShell, strSource, strTarget, strOldName, strNewName
'
set objFSO = CreateObject("Scripting.FileSystemObject")
'
' Set up starting folders
'
strSource = "O:\"
strTarget = "N:\"
'
call RecurseDir(strSource, strTarget)
'
' // Recursively copy all files and folders
'
Sub RecurseDir(strSource, strTarget)
wscript.echo "source: " & strSource & " target: "& strTarget
'
Dim strTempSource, strTempTarget
'
Set strTempSource = objFSO.GetFolder(strSource)
'
Wscript.Echo "Begin Value: " & strTarget
'
If Not objFSO.FolderExists(strTarget) Then
' Wscript.Echo "No Folder! Creating folder [" & strTarget & "]"
objFSO.CreateFolder(strTarget)
Else
Wscript.Echo "Folder exists! " & strTempTarget
End If
'
Set strTempTarget = objFSO.GetFolder(strTarget)
' ** Copy files from current directory to target
For each file in strTempSource.files
strOldName = strSource & "\" & file.name
strNewName = strTempTarget & "\" & Mid(file.name, 1, InstrRev(file.name, ".")) & "ts"
'
If Not objFSO.FileExists(strNewName) Then
Set objShell = CreateObject("WScript.Shell")
'
Wscript.Echo "Transcoding file: " & strOldName & " to " & strNewName
'
Select Case Right(strOldName, 3)
Case "avi"
wscript.echo "vlc file://""" & strOldName & """ :sout=#duplicate{dst=std{access=file,mux=ts,dst=""" & strNewName & """}} vlc://quit"
objShell.Run "vlc file://""" & strOldName & """ :sout=#duplicate{dst=std{access=file,mux=ts,dst=""" & strNewName & """}} vlc://quit", 1, True
Case "mp4"
wscript.echo "vlc file://""" & strOldName & """ :sout=#transcode{vcodec=mp2v,vb=1024,scale=1,acodec=mp2a,ab=192,channels=2}:duplicate{dst=std{access=file,mux=ts,dst=""" & strNewName & """}} vlc://quit"
objShell.Run "vlc file://""" & strOldName & """ :sout=#transcode{vcodec=mp2v,vb=1024,scale=1,acodec=mp2a,ab=192,channels=2}:duplicate{dst=std{access=file,mux=ts,dst=""" & strNewName & """}} vlc://quit", 1, True
End Select
'
Set objShell = Nothing
End If
Next
' ** For each subfolder of current dir, copy files to target and recurse its subdirs
For each subdir in strTempSource.subfolders
Wscript.Echo subdir.path
call RecurseDir(subdir.path, strTempTarget & "\" & subdir.name)
Next
End Sub
</pre>

== Non-Interactive Batch Transcoding (Linux)==
To transcode several files without user interaction create a bash script in the folder where the files are contained and add these lines to the bash script:

<pre>
#!/bin/bash
vcodec="VIDEO_CODEC"
acodec="AUDIO_CODEC"
bitrate="VIDEO_BITRATE"
arate="AUDIO_BITRATE"
ext="OUTPUT_EXT"
mux="MUXER"
vlc="PATH_TO_VLC"
fmt="INPUT_EXT"

for a in *$fmt; do
$vlc -I dummy -vvv "$a" --sout "#transcode{vcodec=$vcodec,vb=$bitrate,acodec=$acodec,ab=$arate,channels=6}:standard{mux=$mux,dst=\"$a.$ext\",access=file}"vlc://quit
done
</pre>

===Non-Interactive Merge/Transcode (Windows)===

If you have more than one source files that need to be merged and transcoded resulting in a single out put file create a batch script with the following line in it:

<pre>
"PATH_TO_VLC" -vvv FILE1.EXT FILE2.EXT FILE3.EXT ETC.ETC --sout-keep --sout=#gather{} --sout=#transcode{vcodec=h264,vb=1024,scale=1,acodec=mp4a,ab=192,channels=6}:standard{access=file,mux=ts,dst=out.mpg} --sout-all
</pre>

===Example script===
As an example, here is a bash script that will take a <tt>.mpg</tt> file as generated by an DVB capture device and transcode it into an MPEG4 file using the h.264 codec. Copy it to a file, for example <tt>dvb2mp4</tt>, and make it executable. It should work on any operating system that has bash, including windows if [http://www.cygwin.com Cygwin] is installed. It uses the cropping parameters proposed at [[Wikipedia:Overscan_amounts]] adapted so that the dimensions are divisible by 16 for better encoding.

<pre>
#!/bin/bash
#
# Transcode DVB TV signals to h.264-encoded MP4 files using VLC
# Wout.Mertens@gmail.com

#### Defaults, please edit for your settings ####

# VLC location, here is the Mac OS X example
VLC=/Applications/VLC.app/Contents/MacOS/clivlc
# Other possibilities: (Remove the # to activate)
#VLC=/usr/bin/vlc
#VLC=/usr/local/bin/vlc

# 16:9 or 4:3
aspect=16:9

# PAL (Europe) or NTSC (US)
src=PAL

# video bitrate
bitrate=1024

# audio bitrate
arate=128

# cropping?
crop=yes

# Deinterlace?
deint=yes

#### Program, do not change below this line ####
usage() {
cat 1>&2 <<EOF
Usage: $0 [-swpncC] [-b <rate>] [-a <rate>] <DVB source .mpg> <MP4 output file>
-s 4:3 aspect ratio (default=$aspect)
-w 16:9 aspect ratio
-p PAL (720x576) input (default=$src)
-n NTSC (720x480) input
-c Crop borders (default=$crop)
-C Do not crop borders
-d Perform de-interlacing (default=$deint)
-D Do not perform de-interlacing
-b video bitrate kb/s (default=$bitrate)
-a audio bitrate kb/s (default=$arate)
EOF
exit 1
}

error() {
echo "ERROR: $*" 1>&2
exit 2
}

while getopts 'swpncCb:a:h' opt; do
case $opt in
s) aspect=4:3 ;;
w) aspect=16:9 ;;
p) src=PAL ;;
n) src=NTSC ;;
c) crop=yes ;;
C) crop=no ;;
d) deint=yes ;;
D) deint=no ;;
b) bitrate=$OPTARG ;;
a) arate=$OPTARG ;;
h) usage ;;
*) echo "Unknown option $opt" 1>&2; usage ;;
esac
done
shift $(( $OPTIND - 1 ))

[ $# -ne 2 ] && usage

infile="$1"
outfile="$2"
case $outfile in
*.mp4|*.MP4) : ;;
*) outfile="$outfile.mp4" ;;
esac

[ -r "$infile" ] || error "Can't read from $infile"

case "$src,$aspect,$crop" in
PAL,16:9,yes) sizestr="cropleft=31,cropright=31,croptop=16,cropbottom=16,width=960,height=544" ;;
PAL,4:3,yes) sizestr="cropleft=31,cropright=31,croptop=16,cropbottom=16,width=720,height=544" ;;
NTSC,16:9,yes) sizestr="cropleft=30,cropright=30,croptop=17,cropbottom=17,width=800,height=448" ;;
NTSC,4:3,yes) sizestr="cropleft=26,cropright=26,croptop=17,cropbottom=17,width=608,height=448" ;;
PAL,16:9,no) sizestr="width=1024,height=576" ;;
PAL,4:3,no) sizestr="width=768,height=576" ;;
NTSC,16:9,no) sizestr="width=800,height=448" ;;
NTSC,4:3,no) sizestr="width=608,height=448" ;;
*) error "Could not handle $src,$aspect,$crop. This shouldn't happen!" ;;
esac

if [ "$deint" = "yes" ]; then
deintstr=",deinterlace=enable"
else
deintstr=
fi

# Let's do it
echo "Input file: $infile"
echo "Output file: $outfile"
echo "Encoding at $bitrate+$arate kb/s, input $src, $aspect, cropping $crop, de-interlace $deint"
echo
echo '>>>' $VLC -I dummy "$infile" --sout "#transcode{$sizestr$deintstr,vcodec=h264,vb=$bitrate,acodec=mp4a,ab=$arate}:standard{mux=mp4,dst=\"$outfile\",access=file}" vlc://quit
echo
$VLC -I dummy "$infile" --sout "#transcode{$sizestr$deintstr,vcodec=h264,vb=$bitrate,acodec=mp4a,ab=$arate}:standard{mux=mp4,dst=\"$outfile\",access=file}" vlc://quit
</pre>

[[Category:Glossary]]

WAVE

2008-09-28T01:37:25Z

Fenugrec: vlc://quit

{{mux|id=wav|encoder=y}}

'''WAVE''' is a way of storing audio, which is normally uncompressed. It is based on [[RIFF]].

== Accepted audio codecs ==
* [[dummy]]: Uncompressed audio of various types, based on storing integer values of the amplitude of the sound (see [[wikipedia:PCM|PCM]]).
* [[fl32]]: Floating point 32-bit uncompressed audio, also based on PCM but allowing the values to be stored as floating point data types. This can give better quality audio when the sound becomes quiet.

== Converting to WAVE ==

The commandline for converting any readable input file to a WAVE audio file is the following:

vlc -I dummy -vvv "input.mp3" --sout=#transcode{acodec=fl32,channels=2,ab=128}:standard{access=file,mux=wav,dst="output.wav"} vlc://quit

Where on Windows you need to add installation directory in front of vlc (e.g. "C:\Program Files\VideoLAN\VLC\vlc").

As audio codec (acodec) you can specify one of the above mentioned ones. The bitrate of the output file is specified by the ab parameter.

== Source code ==
{{file|modules/mux/wav.c|output muxer}}
{{file|modules/demux/wav.c|input demuxer}}

VLC HowTo/Make thumbnails

2008-09-28T01:34:41Z

Fenugrec: changed to vlc://quit for 0.9

{{howto|make a thumbnail}}
==How to create a thumbnail from a video==

For all those people wanting a thumbnail from a video, use the following command (Windows):

<pre>vlc -V image --start-time 0 --stop-time 1 --image-out-format jpg --image-out-ratio 24 --image-out-prefix snap test.mpg vlc://quit</pre>

===What it does:===

When {{VLC}} runs it 'plays' the video for one second without actually showing the video on screen, and then quits, leaving us with a file named 'snap000000.jpg', containing an image of the first frame of the video.

===How it works:===

First select the image output with: '''-V image''' or '''--vout image'''.

Next set the interval (in seconds) you want an image from with: '''--start-time 0 --stop-time 1'''
In my example the first second of the video. In that case you could omit the parameter --start-time. If you want an image from the 5th second fill in: '''--start-time 5 --stop-time 6'''

The image format will be .jpg because i provided: '''--image-out-format jpg'''. You could specify '''--image-out-format png''' to get a .png-image instead.

'''--image-out-ratio 24''' specifies we want one image out of 24. In my case the video contains 24 images per second so this is the right value. If your video has more images per seconds you should increase this value to prevend you get more images as one. If the number is too high (for example 500) it still produces only one image, so the actual value is not so important as long as it is higher then the images per second.

'''--image-out-prefix snap''' specifies the filename must start with 'snap'. You can prefix with a path, for example c:\snap and resulting images will be created there.

You can specify '''--image-out-replace'''. In that case Vlc produces the file 'snap.jpg'. This will prevent VLC from creating multiple images.

'''test.mpg''' specifies the video to play and finally '''vlc://quit''' forces vlc to quit when ready.