ffprobe
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ffprobe [2019-09-23 12:16:47] mi created |
ffprobe [2023-06-08 15:10:59] (current) mi [Show video format] |
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| The normal text output of ''ffprobe'' goes to stderr, so you usually need to add ''2>&1'' to parse the output. The alternative is to use the complex ffprobe options to format the output which then goes to stdout. | The normal text output of ''ffprobe'' goes to stderr, so you usually need to add ''2>&1'' to parse the output. The alternative is to use the complex ffprobe options to format the output which then goes to stdout. | ||
| + | Start with a look at this page: https://trac.ffmpeg.org/wiki/FFprobeTips | ||
| + | |||
| + | ===== Show metadata tags===== | ||
| + | |||
| + | ffprobe -v quiet "$in" -print_format json -show_entries stream_tags:format_tags | ||
| + | |||
| + | (for ''-print_format'', there is also ''flat'', ''xml'', ''csv'', etc.) | ||
| + | |||
| + | ===== Show video format===== | ||
| + | |||
| + | ffprobe -v warning -select_streams v -show_entries stream=codec_name,height,width,pix_fmt -of csv=p=0 "$in" | ||
| + | |||
| + | ===== Has alpha channel? ===== | ||
| + | |||
| + | https://stackoverflow.com/questions/69029439/a-good-way-to-detect-alpha-channel-in-a-video-using-ffmpeg-ffprobe | ||
| + | |||
| + | <code bash>for f in *.mov; do | ||
| + | pixfmt=$(ffprobe -v 0 -select_streams v:0 -show_entries stream=pix_fmt -of compact=p=0:nk=1 "$f") | ||
| + | alpha=$(ffprobe -v 0 -show_entries pixel_format=name:flags=alpha -of compact=p=0 | grep "$pixfmt|" | grep -oP "(?<=alpha=)\d") | ||
| + | if (( alpha )); then echo "$f : yes, has alpha"; else echo "$f : NO"; fi | ||
| + | done | ||
| + | </code> | ||
| ===== List audio tracks ===== | ===== List audio tracks ===== | ||
| - | ffprobe "$in" 2>&1 | perl -nle '/^\s+Stream #(\d+:\d+): Audio/ && print $1' | + | ffprobe "$in" 2>&1 | perl -nle '/^\s+Stream #(\d+:\d+).*?: Audio/ && print $1' |
| | | ||
| with codec and number of channels: | with codec and number of channels: | ||
| - | ffprobe "$in" 2>&1 | perl -nle '/^\s+Stream #(\d+:\d+): Audio: (\S+).*(\d+)\s+channels/ && print join("\t", $1, $2, $3)' | + | ffprobe "$in" 2>&1 | perl -nle '/^\s+Stream #(\d+:\d+).*?: Audio: (\S+).*(?:(\d+)\s+channels)?/ && print join("\t", $1, $2, $3)' |
| or to have the tracks in a Bash array: | or to have the tracks in a Bash array: | ||
| Line 17: | Line 39: | ||
| or the "official" way: | or the "official" way: | ||
| - | ffprobe -select_streams a -show_entries stream=index -of csv=p=0 "$in" | + | ffprobe -v quiet -select_streams a -show_entries stream=index -of csv=p=0 "$in" |
| | | ||
| - | ffprobe -select_streams a -show_entries stream=index,codec_name,channels -of csv=p=0 "$in" | + | ffprobe -v quiet -select_streams a -show_entries stream=index,codec_name,channels -of csv=p=0 "$in" |
| | | ||
| - | audio_tracks=( $(ffprobe -select_streams a -show_entries stream=index -of csv=p=0 "$in") ) | + | audio_tracks=( $(ffprobe -v quiet -select_streams a -show_entries stream=index -of csv=p=0 "$in") ) |
| + | |||
| + | ===== List subtitles ===== | ||
| + | |||
| + | ffprobe -v quiet -select_streams s -show_entries stream=index,codec_name:stream_tags=language -of csv=p=0 "$in" | ||
| + | |||
| + | (but for mkv, better see [[mkv]]) | ||
| + | |||
| + | |||
| + | ===== Check Volume ===== | ||
| + | For example to detect silent tracks/channels | ||
| + | |||
| + | ffmpeg -i "$in" -map 0:a -af "astats=measure_overall=none:measure_perchannel=Max_level" -f null - | ||
| + | |||
| + | ffmpeg -i "$in" -map 0:a -af "astats=measure_overall=none:measure_perchannel=Max_level" -f null - 2>&1 | grep -E '(Channel|Max level):' | ||
| + | |||
| + | ffmpeg -i "$in" -vn -sn -dn -map 0:a -af "astats=measure_overall=none" -f null - 2>&1 \ | ||
| + | | perl -nle 'if (($id, $var, $val)=/^\[Parsed_astats_0 \@ 0x([\da-f]+)] (Channel|Max level): ([\d\.]+)/) { if ($var=~/Channel/) { if (!$t || $id ne $h{$t}{id}) {$t++; $h{$t}{id}=$id;} $c=$val;} elsif ($var=~/level/) {print "$t.$c $var = $val";} }' | ||
| + | |||
| + | Or with ''volumedetect'', but it mixes all channels into a single value | ||
| + | |||
| + | ffmpeg -i "$in" -map 0:a -af "volumedetect" -f null - 2>&1 | grep max_volume | ||
| + | |||
| + | ===== Audio checksums ===== | ||
| + | |||
| + | for track in $(ffprobe -v error -select_streams a -show_entries stream=index -of csv=p=0 "$in"); do \ | ||
| + | ffmpeg -i "$in" -vn -map 0:$track -c:a copy -f md5 - 2>/dev/null \ | ||
| + | | while read md5; do \ | ||
| + | printf "%32s Audio Track %2d %s\n" $md5 $track "$in"; \ | ||
| + | done; \ | ||
| + | done | ||
| ===== Timecode ===== | ===== Timecode ===== | ||
| Line 30: | Line 83: | ||
| ===== Other options ===== | ===== Other options ===== | ||
| - | -sections | + | <code> |
| - | Print sections structure and section information, and exit. The output is not meant to be parsed by a machine. | + | -sections |
| - | + | Print sections structure and section information, and exit. The output is not meant to be parsed by a machine. | |
| - | -show_data_hash algorithm | + | |
| - | Show a hash of payload data, for packets with -show_packets and for codec extradata with -show_streams. | + | |
| + | -show_data_hash algorithm | ||
| + | Show a hash of payload data, for packets with -show_packets and for codec extradata with -show_streams. | ||
| + | </code> | ||
| | | ||
/docs/dokuwiki/data/attic/ffprobe.1569233807.txt.gz · Last modified: 2019-09-23 12:16:47 by mi
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