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A reminder of the importance of asking questions [1]

1 How to I convert to OGG?
- 1.1 Converting a Video to OGG/Theora
- 1.2 Converting Audio to OGG/Vorbis
2 How can I convert my movie into the flash (FLV) format?
3 Editing with mplayer / mencoder
4 Capturing DV format video with dvgrab
5 Transcoding to DV
6 How do I convert a Movie to Images
- 6.1 with ffmpeg
- 6.2 with mplayer
7 How do I convert images to a movie?
8 Screen Grabbing
9 How can I make audio files from a DVD?
10 What are other good resources on the web?
11 Questions that are not on this page, but should be

[edit] How to I convert to OGG?

[edit] Converting a Video to OGG/Theora

An example of a simple BASH script to transcode a file, using ffmpeg2theora.

The resulting movie uses OGG as the file (or container) format, and the Theora codec for the video data.

#!/bin/bash -x
#
# makeogv
#
i=$1
base=`basename $i`
o=${base%.*}.ogv
# ffmpeg -y -i "$i" -ac 2 -ab 80 -ar 48000 -acodec libvorbis -qscale 9 -r 15 -s 320x240 "$o"
ffmpeg2theora  -o "$o" --channels=2 --samplerate=48000 -x 320 -y 240 "$i"

[edit] Converting Audio to OGG/Vorbis

Here is an example of using ffmpeg to convert a WAV audio file into OGG/Voribs. Note that OGG is the file or "container" format, and "vorbis" is the actual compression technique (codec) for the audio.

This command uses the -ss and -t options to start at 3 minutes into the file (3*60 seconds), with a duration of 60 seconds.

ffmpeg -i xabier.wav -ss 180 -t 60 -acodec libvorbis -ab 192000 xabier_sample.ogg

[edit] How can I convert my movie into the flash (FLV) format?

An example of a simple BASH script to transcode a file, using ffmpeg.

#!/bin/bash -x
#
# makeflv
#
i=$1
base=`basename $i`
o=${base%.*}.flv
ffmpeg -y -i "$i" -ab 48 -ar 22050 -qscale 9 -r 15 -s 320x240 "$o"

[edit] Editing with mplayer / mencoder

Extracting a clip (cutting)

playing a particular portion in this case endpos determines the total duration of the shot (end position relative to adjusted start position)

mplayer -ss 2:05 -endpos 3 dvgrab-001.avi

Make an edit (extract to new file)

note -oac copy, -ovc copy, KEEP THE ORIGINAL FORMAT (fastest & no recompression/change of data, video quality unchanged) Here, we first make a subdirectory (clips) to hold (& later make selecting) the edits.

mkdir clips
mencoder -ss 2:05 -endpos 3 dvgrab-001.avi -oac copy -ovc copy -o clips/01.avi

Make some more clips...

mencoder -ss 4:00 -endpos 3 dvgrab-001.avi -oac copy -ovc copy -o clips/02.avi
mencoder -ss 2:00 -endpos 3 dvgrab-001.avi -oac copy -ovc copy -o clips/03.avi

View your "rough cut"...

mplayer clips/*

Try a random edit?

mplayer -shuffle clips/*

(or even ;)

mplayer -flip -shuffle clips/*

PERFORMING the edit

mencoder -oac copy -ovc copy -o edit.avi clips/*

Controlled loop, 2 times:

mencoder -oac copy -ovc copy -o edit2.avi edit.avi edit.avi

Example of "Appending multiple AVI" from net:

As a side-effect, the broken AVI fixer function enables MEncoder to append 2 (or more) AVI files:

cat 1.avi 2.avi | mencoder -noidx -ovc copy -oac copy -o output.avi -

Note: This expects 1.avi and 2.avi to use the same codecs, resolution, stream rate etc, and at least 1.avi must not be broken. You may need to fix your input AVI files first, as described above.

http://web.njit.edu/all_topics/Prog_Lang_Docs/html/mplayer/encoding.html

Compressing to a Flash Video(flv)

ffmpeg -y -i IN.OGG -ab 48 -ar 22050 -qscale 9 -r 15 -s 320x240 OUT.FLV

[edit] Capturing DV format video with dvgrab

dvgrab -format raw

[edit] Transcoding to DV

using ffmpeg to go DV (avi)

ffmpeg -y -i dvgrab-001.avi -t 1 -s 640x480 -sameq -vcodec mjpeg -acodec copy dvmjff.avi
then the whole movie
 
mencoder -oac pcm -ovc lavc -lavcopts vcodec=mjpeg -o dvgrab0001mjpeg.avi dvgrab-001.avi
 
mencoder -oac mp3lame -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=600 -o output.avi input.flv

[edit] How do I convert a Movie to Images

[edit] with ffmpeg

ffmpeg -i rearwindow.avi -f image2 -y -r .01 -an rearwindow%06d.jpg

[edit] with mplayer

mplayer -vo png rearwindow.avi

Use sstep to do a time lapse / select one frame per second

mplayer -sstep 25 -vo png rearwindow.avi

(see: mplayer -vo help for other opts)

[edit] How do I convert images to a movie?

Slideshow.py is an example using Python, ImageMagick, and mencoder to convert images into a "slideshow" movie.

[edit] Screen Grabbing

ffmpeg X11 grabbing!

	ffmpeg -f x11grab -s cif -i :0.0 /tmp/out.mpg
		0.0 is display.screen number of your X11 server, same as the DISPLAY environment variable.
 
	ffmpeg -f x11grab -s cif -i :0.0+10,20 /tmp/out.mpg
		0.0 is display.screen number of your X11 server, same as the DISPLAY environment variable. 10 is the
		x&#8722;offset and 20 the y&#8722;offset for the grabbing.

[edit] How can I make audio files from a DVD?

Recently I wanted to make some individual audio files (MP3's) of audio on an "supplementary" audio track of a DVD.

I used mplayer's -dumpaudio option to select the particular audio track I had in mind:

mplayer -aid 130 -dumpaudio -vo null VTS_01_2.VOB

Then I used ffmpeg to convert the whole thing to mp3 format (this step is necessary only because I didn't figure out how to play the dump file with mplayer -- kind of weird that it doesn't recognize it's own dump format -- probably you can manually instruct it as to the format, but in any case ffmpeg recognizes and converting to mp3 allows mplayer to play it again).

ffmpeg -i stream.dump -ar 192000 stream.mp3

Then I figured out a start and end time using mplayer, subtract start from end to get duration, and plug this into ffmpeg. Apparently ffmpeg (version specific?) doesn't deal with time codes (like 3:18), and so values for start (-ss) and duration (-t) need to be given as seconds (so 3:19 becomes 199).

ffmpeg -i stream.mp3 -ss 44 -t 199 -y -ab 192000 03_NameMe.mp3

[edit] What are other good resources on the web?

[edit] Questions that are not on this page, but should be

How to use the HTML5 <video> tag
How to create an RSS feed