[all variants] Convert mp3 to avi

[cudjoe]

Hi,

I need to convert a mp3 to avi because my Upnp player (freebox-tv) does not read mp3 but supports well xvid videos. I thus will transcode my music as blank videos.

With ffmpeg, the conversion is easy :

ffmpeg -i input.mp3 -vn -acodec copy -f avi output.avi

Problem : the output does not have any video stream.

I made a small blank video (attached as txt), 1 black frame.

With mencoder, I managed to have both video and audio :

mencoder black.avi -o output.avi -ovc xvid -oac copy -audiofile input.mp3

Problem : the output file is 1 frame long.

How can I specify to loop over the blank video accordingly to audio stream length ?

Thank you guyz for any ideas!

[FakeOutdoorsman]

Create blank black image (convert is part of the imagemagick package):

convert -size 320x240 xc:black black.png

Or create black image with white text:

convert -size 320x240 xc:black -fill white -draw "gravity Center text 0,0 'The Pogues'" black.png

Combine audio and black video:

ffmpeg -loop_input -i black.png -i fairytale_of_new_york.mp3 -shortest -acodec copy output.avi

You will need to enable restricted encoders in FFmpeg to encode with mpeg4:
HOWTO: Easily enable MP3, MPEG4, AAC, and other restricted encoding in FFmpeg

[Locutus_of_Borg]

save this python script, name it script.py (or whatever you want)

import os, sys                                           

fps = 30

if len(sys.argv) != 4:
    print "Usage: makevid.py imagefile audiofile seconds"
    sys.exit(1)                                          

secs = int(sys.argv[3])
if secs < 0:
    print "Please pass a positive amount of seconds"
    sys.exit(1)
secs = 1 / float(secs)

filesexist = True
for each_file in sys.argv[1:2]:
    if not os.path.exists(each_file):
        print "%s doesn't exist" % each_file
        filesexist = False
if not filesexist: sys.exit(1)

mencoder_cmd = ('mencoder "mf://%s" -mf fps=%f -vf harddup -ovc lavc'\
    ' -lavcopts vbitrate=100 -audiofile "%s" -oac copy -ofps %d'\
    ' -o output.avi') % (sys.argv[1], secs, sys.argv[2], fps)

print "Starting mencoder"
os.system(mencoder_cmd)
print "Video is complete, output written to output.avi"

open a terminal execute the script with

python script.py [imagefile] [audiofile] [length in seconds]

this will create a video of a still image that will play your audio for however many seconds you specify

[cudjoe]

Thanks Locutus_of_Borg.
With the information of Fakeoutdoorsman, I made this small shell script (ffmpeg instead of mencoder) :

input=$1
output=$2

background=/tmp/bng-black.jpg
convert -size 320x240 xc:black $background
duration=`ffmpeg -i $input 2>&1 | grep Duration | cut -f1 -d, | cut -f2,3,4,5 -d:`
ffmpeg -loop_input -i $background -i $input -vcodec mpeg4 -acodec copy -t $duration $output

Thank you very much for your assistance !

[Kilarin]

Thanks! I just used your shell script, replacing the background.jpg with an image I wanted to use, and converted an mp3 file into an avi! It was EASY with the script. thank you VERY much!

[FakeOutdoorsman]

I updated my first post to now use the -shortest option which will automatically finish encoding the video when the music ends. Much easier than getting the audio duration and then using that number to determine the encoding length. So now cudjoe's script can look like this:

#!/bin/bash
# Usage: mp32avi.sh input.mp3 output.avi
input=$1
output=$2

background=/tmp/bng-black.jpg
convert -size 320x240 xc:black $background
ffmpeg -loop_input -i $background -i $input -vcodec mpeg4 -acodec copy -shortest -qscale 5 $output

What would be interesting is to get the artist and/or title tag from the audio metadata and feed that to the "create black image with white text" (post #2) example for convert.

Update: I also added -qscale 5 to cudjoe's script so the output quality should be better for more complicated backgrounds other than just a solid color.

[Lars Noodén]

@ FakeOutdoorsman : That looks useful. Sorry for a dumb question: Does that method wrap the MP3s as AVI as is, or does it transcode them and reduce the sound quality further?

[FakeOutdoorsman]

Originally Posted by Lars Noodén @ FakeOutdoorsman : That looks useful. Sorry for a dumb question: Does that method wrap the MP3s as AVI as is, or does it transcode them and reduce the sound quality further?

There is no re-encoding of the audio in the script because it is using the -acodec copy option. It is basically copying the audio from the MP3 file and pasting it into an AVI file.

There is a -vcodec copy option as well which is quite useful. Both of these options are good for trimming a video without re-encoding or adding/removing audio/video to a file without any need to re-encode.

[FakeOutdoorsman]

Here's a new version:

• add the title to the black background
• use gif because it is faster to decode than png apparently
• set frame rate
• add requirements
• make background randomly named and then delete it

#!/bin/bash
# Requires: imagemagick, ffmpeg
# Usage: ./mp32avi.sh input.mp3 output.avi

background=/tmp/$RANDOM.gif

title=`ffmpeg -i $1 2>&1 | grep TIT2 | cut -d: -f 2`

convert -size 320x240 xc:black -fill white -draw "gravity Center text 0,0 '$title'" $background

ffmpeg -loop_input -r ntsc -i $background -i $1 -acodec copy -shortest -qscale 5 $2

rm $background

exit

[Kilarin]

this scrip creates the avi just fine, but the background is plain black. For some reason its not grabbing the mp3 title info.

I made certain the title was populated in both v1 and v2 tags. Am I missing some component?

thanks again!