linux file conversion

PDF to MP3:

pdftotext filename.pdf

cat filename.txt | sed 's/[^a-zA-Z0-9 .,!?]//g' > filename_nosym.txt

text2wave filename_nosym.txt

lame -f filename_nosym.wav filename_nosym.mp3

use "file" to see what something is:

$ file video.flv

video.flv: Macromedia Flash Video

http://www.ubuntugeek.com/convert-flv-google-videos-to-mpg-using-ffmpeg.html

FLV to MPG:

ffmpeg -i name.flv name.mpg

Loop to convert OGG to MP3

for x in *.ogg; do ffmpeg -i "$x" "`basename "$x" .ogg`.mp3"; done

http://www.brighthub.com/computing/linux/articles/40293.aspx

Take screenshots

ffmpeg -i file.mp4 -r 1/5 filename%03d.jpg

use ffmpeg to crop an mp3. Starting at 30 seconds, grab 25 seconds from bar.mp3

ffmpeg -ss 00:00:30.00 -t 25 -i bar.mp3 -acodec copy bar-new.mp3

Suppose I wanted the beginning to 16:33 of a mp3 of length 17:08

ffmpeg -ss 00:00:00.00 -t 993 -i bar.mp3 -acodec copy bar-new.mp3

shell script for downloading youtube flv:

http://www.linux.com/articles/56642

Rip just the audio:

http://justanothertechblog.blogspot.com/2007/02/easily-extract-audio-from-any-youtube.html

$ ffmpeg -i input.flv -f mp3 -vn -acodec copy output.mp3

http://www.ehow.com/how_5066124_convert-mp-mp-linux.html

http://intuitivenipple.net/10/converting-mp3s-to-m4b-audiobooks-and-m4b-to-mp3

M4B to MP3:

$ ffmpeg -i <infile.m4b> -acodec libmp3lame -ar 22050 <outfile.mp3>

$ for m4b in $(ls -1 *.m4b); do ffmpeg -i $m4b -acodec libmp3lame -ar 22050 ${m4b}.mp3; done

create animated gif from set of png frames:

convert -delay 30 *.png -loop 0 playme.gif

convert *.png Nc\=5_N\=3to30_d\=1_full_prefactor\=5_matrices.gif

convert *.png Nc\=5_N\=3to30_d\=1_full_prefactor\=5_point_distribution.gif

Note: all the source pictures must be the same dimensions and the same file type

http://www.linux.com/articles/46124

the following takes matlab output png, crops and makes white transparent:

convert -transparent white -crop 960x450+140+230 plot_Eyz_sweep_angle_pcolor_*.png plot_Eyz_sweep_angle_pcolor_transparent.png

Before making the gif, rename the png so that numbers go from 00 to 39 instead of 0 to 39

mmv 'plot_Eyz_sweep_angle_pcolor_transparent-?.png' 'plot_Eyz_sweep_angle_pcolor_transparent-0#1.png'

The convert command I was using is

convert -delay 50 plot_Eyz_sweep_angle_pcolor_transparent-*.png plot_Eyz_sweep_angle_pcolor_trans.gif

However, this doesn't redraw between frames, which can be a problem for transparent frames.

convert -debug cache -verbose -limit memory 64MiB -delay 10 L300_W5_Intensity_freq0000*.png L300_W5_Intensity_freq_scan.gif

use GIMP:

"Open as layers"

"Save as," change to .gif. "Save as animation"

300 millisecond delay, "Frame disposal where unspecified: One frame per layer (replace)"