Date created: Tuesday, March 2, 2021 10:19:43 AM. Last modified: Sunday, September 17, 2023 11:47:49 AM
Music & Media Commands
Audio
sudo apt-get install ffmpeg
Splitting Files
Split flac file with cue file:
sudo apt-get install cuetools shntool flac
shnsplit -f file.cue -t %n-%t -o flac file.flac
Converting AIFF to WAV and Renaming
ffmpeg using find with bash sub-string replacement to change the filename ending:
find . -iname "*.aiff" -execdir sh -c 'x="{}"; ffmpeg -i "$x" "${x%.aiff}.wav"' \;
Converting Audio to FLAC
Need to specify the sample depth and sample frequency, to match the input files (in this case 16-bit 44.1Khz APE files):
for file in *.ape; do ffmpeg -i "$file" -af aformat=s16:44100 "${file/ape/flac}"; done
Converting Audio to MP3
Convert from flac directly to 320Kbps MP3:
# sudo apt-get install lame ffmpeg libavcodec-extra-53
for f in *.flac; do ffmpeg -i "$f" -acodec libmp3lame -ab 320k "${f%.flac}.mp3"; done
# Alternative:
find -name "*.flac" -exec ffmpeg -i {} -acodec libmp3lame -ab 320k {}.mp3
Decompress from flac to wav, then encode to mp3 320k
mkdir temp
flac -d *.flac
for f in *.wav; do lame -b 320k "$f" ./temp/"${f%.wav}.mp3"; done
rm *.wav
Convert m4a/wma/flac audio to mp3 audio:
$ ffmpeg -i input_file.aac -acodec libmp3lame -ab 320k output_file.mp3
$ ffmpeg -i input_file.ac3 -acodec libmp3lame -ab 320k output_file.mp3
$ ffmpeg -i input_file.flac -acodec libmp3lame -ab 320k output_file.mp3
$ ffmpeg -i input_file.m4a -acodec libmp3lame -ab 320k output_file.mp3
$ ffmpeg -i input_file.ogg -acodec libmp3lame -ab 320k output_file.mp3
$ ffmpeg -i input_file.wav -acodec libmp3lame -ab 320k output_file.mp3
$ ffmpeg -i input_file.wma -acodec libmp3lame -ab 320k output_file.mp3
Convert video to audio:
When converting from a video file to an audio file, if the output audio file type and encoding isn't specified, the output file may be an video file, -vn tells ffmpeg to ignore the video stream so that the output is audio only:
ffmpeg -i Input_File.flv -vn -acodec copy
Converting Video to Audio
Convert mp4 video to mp3 (audio only):
# -i input file
# -acodec output audio codec
# -ac audio channels
# -b:a exact bitrate
# -ar audio sampling frequency
ffmpeg -i Input-Video.mp4 -acodec libmp3lame -ac 2 -b:a 320k -ar 48000 Output-Audio.mp3
# Convert all files in the current directory, using basename to replace the filename ending with mp3:
for file in *.mp4; do ffmpeg -i "$file" -acodec libmp3lame -ac 2 -b:a 320k -ar 48000 "`basename -s ".mp4" "$file"`.mp3"; done
# Instead of basename, if using BASH, us the built-in substring replacement method:
for file in *.mp4; do ffmpeg -i "$file" -acodec libmp3lame -ac 2 -b:a 320k -ar 48000 "${file/mp4/mp3}"; done
Pictures
# Provides "convert"
sudo apt-get install imagemagick-6.q16
# Provides "exiftool"
sudo apt-get install libimage-exiftool-perl
Resizing Pictures
Resize by percentage:
convert infile.jpg -resize 50x50% outfile.jpg
Reduce quality to a certain percentage of original:
convert infile.jpg -quality 40 outfile.jpg
EXIF Data
Removing EXIF data:
exiftool -all= image.jpg
HEIC
Convert to JPG
sudo apt-get install libheif-examples
for file in *.heic; do heif-convert $file ${file/%.heic/.jpg}; done
Video
Joining Files
Rename video segments to remove trailer then join them together:
$ ls -1
segment100_2296000_av.ts?null=0
segment101_2296000_av.ts?null=0
segment102_2296000_av.ts?null=0
segment10_2296000_av.ts?null=0
$ rename 's/\?null=0//' *
$ ls -1
segment100_2296000_av.ts
segment101_2296000_av.ts
segment102_2296000_av.ts
segment10_2296000_av.ts
$ ffmpeg -i "concat:segment1_2296000_av.ts|segment2_2296000_av.ts|segment3_2296000_av.ts" -c copy -bsf:a aac_adtstoasc output.mp4
Join split audio and video files:
# -c means copy the original codecs as-is, don't re-encode:
ffmpeg -i audiofile.m4a -i videofile.m4v -c copy combined.mp4
for file in *.m4a; do ffmpeg -i "${file}" -i "${file/m4a/m4v}" -c copy "${file/m4a/mp4}"; done
Remove the audio from a video:
ffmpeg -i $1 -c copy -an "$1-nosound.${1#*.}"
Downscale a video:
#Scale by input width / 2 and input height / 2 to keep the same aspect ratio
ffmpeg -i input.avi -vf scale="iw/2:ih/2" output.avi
Convert to GIF
Convert a video file to a gif:
"Control looping with -loop output option but the values are confusing. A value of 0 is infinite looping, -1 is no looping, and 1 will loop once meaning it will play twice. So a value of 10 will cause the GIF to play 11 times."
ffmpeg -i input.mp4 -vf "fps=20,scale=320:-1:flags=lanczos,split[s0][s1];[s0]palettegen[p];[s1][p]paletteuse" -loop -1 output.gif
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