Command-line cinema : Différence entre versions
(→Wget) |
(→Extracting Frames from a Movie: ffmpeg) |
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= Extracting Frames from a Movie: ffmpeg = | = Extracting Frames from a Movie: ffmpeg = | ||
| − | + | ffmpeg -i <source> <destination%06d.jpg> | |
| + | |||
| + | ffmpeg -ss 12:00 -i <source> -vframes 100 <destination%04d.jpg> | ||
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Timing (start + stop) can be controlled with -ss (skip start) and -t (total time of result) | Timing (start + stop) can be controlled with -ss (skip start) and -t (total time of result) | ||
When -ss is before the -i ffmpeg attempts to JUMP which is fast only precise to the nearest key frame. | When -ss is before the -i ffmpeg attempts to JUMP which is fast only precise to the nearest key frame. | ||
| − | + | # Extract 3 seconds starting at (near) 05:47 and save as snip.mp4 | |
| − | ffmpeg -ss 05:47 | + | ffmpeg -ss 05:47 -i ten.mp4 -t 3 snip.mp4</pre> |
| + | |||
When you put -ss after the -i, the timing is more precise but it's slower as the movie is actually played (quickly) up to that precise point. | When you put -ss after the -i, the timing is more precise but it's slower as the movie is actually played (quickly) up to that precise point. | ||
| − | + | # Extract 3 seconds starting at (exactly) 05:47 and save as snip.mp4 | |
| − | ffmpeg -i ten.mp4 -ss 05:47 -t 3 snip.mp4 | + | ffmpeg -i ten.mp4 -ss 05:47 -t 3 snip.mp4 |
| + | ffmpeg -ss 05:47 -i powersof10/ten.mp4 -vframes 10 snip%04d.jpg | ||
| − | ffmpeg -ss 05:47 -i powersof10/ten.mp4 -vframes 10 snip%04d.jpg | + | # Starting at 05:47 output one frame every 5 seconds for 10 frames, save using names starting snip0001.jpg |
| + | ffmpeg -ss 05:47 -i powersof10/ten.mp4 -r 1/5 -vframes 10 snip%04d.jpg | ||
| − | # | + | # Combine Image Sequence starting frames000001.jpg and the audio in soundtrack.wav |
| − | + | # Save result as "result.mp4" | |
| + | ffmpeg -i frames%06d.jpg -i soundtrack.wav result.mp4 | ||
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Example: | Example: | ||
| − | + | ffmpeg -ri 10 -i frame%06d.jpg -i apologie.wav apologie.mp4 | |
| + | |||
To force ffmpeg to OVERWRITE any previously existing file (useful when inside a larger script that you want to run again and again) -- add the -y to "AUTO-YES" the question about replacing the output. | To force ffmpeg to OVERWRITE any previously existing file (useful when inside a larger script that you want to run again and again) -- add the -y to "AUTO-YES" the question about replacing the output. | ||
| − | + | ffmpeg -r 10 -i frame%06d.jpg -i apologie.wav -y apologie.mp4 | |
= extraction de sons = | = extraction de sons = | ||
Version du 16 octobre 2017 à 09:21
Sommaire
Some Sources of copyleft materials online
example: Fats Waller on archive.org
Youtube-dl
youtube-dl URL
There are *many* interesting options with youtube-dl
Show formats available:
youtube-dl -F URL
Download a particular format (using its numeric code)
youtube-dl -f43 URL
Download a video + the automatically generated subtitles!
youtube-dl --write-auto-sub URL
Wget
Wget is a simple way to download things from the web. These can be webpages, videos, sounds -- basically anything that has a proper URL to access it (for youtube videos or other "closed" sources see youtube-dl)
wget URL
Mplayer
Basic key commands when playing a movie with mplayer
SPACE: Pause/Play . : Forward one frame Left + Right : Jump 9 0 : Volume [ ] : Speed o : Toggle display mode (shows current time and duration) f : Toggle fullscreen s : Save current frame (with -vf screenshot, see Mplayer Snapshots) q : Quit
Time options
# Play from 10 seconds to 1 minute 6 seconds. mplayer -ss 10 -endpos 56 # Play from 01:10:30 - 01:11:00 mplayer -ss 01:10:30 -endpos 30
Extracting Frames from a Movie: Mplayer Snapshots
mplayer -vf screenshot <source>
Then while the movie is playing ... press the s key each time you want to save a frame. You should find files named like:
shot0001.png shot0002.png shot0003.png shot0004.png
Extracting Frames from a Movie: ffmpeg
ffmpeg -i <source> <destination%06d.jpg>
ffmpeg -ss 12:00 -i <source> -vframes 100 <destination%04d.jpg>
Timing (start + stop) can be controlled with -ss (skip start) and -t (total time of result)
When -ss is before the -i ffmpeg attempts to JUMP which is fast only precise to the nearest key frame.
# Extract 3 seconds starting at (near) 05:47 and save as snip.mp4 ffmpeg -ss 05:47 -i ten.mp4 -t 3 snip.mp4</pre>
When you put -ss after the -i, the timing is more precise but it's slower as the movie is actually played (quickly) up to that precise point.
# Extract 3 seconds starting at (exactly) 05:47 and save as snip.mp4 ffmpeg -i ten.mp4 -ss 05:47 -t 3 snip.mp4
ffmpeg -ss 05:47 -i powersof10/ten.mp4 -vframes 10 snip%04d.jpg
# Starting at 05:47 output one frame every 5 seconds for 10 frames, save using names starting snip0001.jpg ffmpeg -ss 05:47 -i powersof10/ten.mp4 -r 1/5 -vframes 10 snip%04d.jpg
# Combine Image Sequence starting frames000001.jpg and the audio in soundtrack.wav # Save result as "result.mp4" ffmpeg -i frames%06d.jpg -i soundtrack.wav result.mp4
Example:
ffmpeg -ri 10 -i frame%06d.jpg -i apologie.wav apologie.mp4
To force ffmpeg to OVERWRITE any previously existing file (useful when inside a larger script that you want to run again and again) -- add the -y to "AUTO-YES" the question about replacing the output.
ffmpeg -r 10 -i frame%06d.jpg -i apologie.wav -y apologie.mp4
extraction de sons
ffmpeg -i <source> output.wav
Padding audio
Add 10 seconds to start and 30 seconds to end of input, save as output:
sox input.wav output.wav pad 10 30
Mixing audio
with ffmpeg
<source lang="bash">ffmpeg -i apologie.wav -i badmusic.wav -filter_complex amerge mix.mp3</source> it uses the duration of the shortest file.
you can also explicitly limit the number of audio channels with:
<source lang="bash">ffmpeg -i apologie.wav -i badmusic.wav -filter_complex amerge -ac 1 mix.mp3</source>
Sequence (concatenate) audio / video
For audio, you can use sox like this:
sox a.wav b.wav c.wav output.wav
For video, you can use mlt / melt .....
melt a.mp4 b.mp4 c.mp4 -consumer avformat:output.mp4 b=1000k
You can also use melt to combine still images as "inter-titles", the numbers with "out" are frames (so for output at 25 fps, 50 = 2 seconds):
melt title2-0.png out=50 \ video.mp4 \ title2-1.png out=100 \ -consumer avformat:output.mp4 b=1000k
To do this with ffmpeg you need to make a sort of playlist file that looks like:
playlist.txt
file 'a.wav' file 'b.wav' file 'c.wav'
<source lang="bash">ffmpeg -f concat -i concat.txt concat.mp3</source> See: https://trac.ffmpeg.org/wiki/Concatenate
Text / Titles
Imagemagick! http://www.imagemagick.org/Usage/text/
convert -size 640x480 -gravity center -pointsize 72 -font CoupeurBoldBlock.otf -background lightblue -fill blue caption:'HEY what about a very long text then?' title.png
with a newline:
convert -size 640x480 -gravity center -pointsize 72 -font CoupeurBoldBlock.otf -background lightblue -fill blue caption:'HEY!what about a very long text then?' title.png
What colors?
convert -list color
Random color!
<source lang="bash">convert -list color | cut -d" " -f1 | shuf | head -n1</source> There's also label:, but it doesn't do word wrap.
<source lang="bash">convert -size 640x480 -gravity center -pointsize 72 -font ~/.fonts/coupeur-boldblock/CoupeurBoldBlock.otf -background lightblue -fill blue caption:'HEY what about a very long text then?' title.png</source>
convert -size 640x480 -gravity center -pointsize 72 -font -background lightblue -fill blue label:'magic\nmagic!!!' whoami.png
title with random colors:
convert -size 640x480 -gravity center -pointsize 72 \
-font ~/.fonts/coupeur-boldblock/CoupeurBoldBlock.otf \
-background $(convert -list color | cut -d" " -f1 | shuf | head -n1) \
-fill $(convert -list color | cut -d" " -f1 | shuf | head -n1) \
label:'Surprise!!!' surprise.png
TITLE
c1=shuf imcolornames.txt | head -n 1 c2=shuf imcolornames.txt | head -n 1 convert -size 640x480 -background $c1 -fill $c2 -pointsize 72 -gravity center -f ont /home/murtaugh/.fonts/OSP_Libertinage/Libertinage-s.ttf label:Contemporaneit y contemporaneity.png
NB: Using the @ sign with label to read from a file seems to be blocked (by some kind of security "policy").... back quoting a file might work though?!
MORNING: RUn through all the different exercises. Talk about free / libre content sources.
