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Magnus HedemarkandGitHub
f92cf52b25
Repairs public FFmpeg evidence references, adds named capability checks, and expands deterministic failure-path coverage. Closes #428.
91 lines
1.9 KiB
Markdown
91 lines
1.9 KiB
Markdown
# Command Cookbook
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These are learning commands, not universal production defaults. Check the installed build, input streams, target requirements, and output with `ffprobe`.
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## Inspect
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```sh
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ffprobe -v error -show_format -show_streams -of json input.mp4
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```
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## List local capabilities
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```sh
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ffmpeg -hide_banner -formats
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ffmpeg -hide_banner -codecs
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ffmpeg -hide_banner -filters
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ffmpeg -hide_banner -encoders
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ffmpeg -hide_banner -hwaccels
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```
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## Remux without re-encoding
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```sh
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ffmpeg -n -i input.mkv -map 0 -c copy output.mp4
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```
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## Explicit transcode
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```sh
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ffmpeg -n -i input.mov -map 0:v:0 -map 0:a:0 \
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-c:v libx264 -crf 20 -preset medium \
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-c:a aac -b:a 160k output.mp4
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```
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## Scale and resample
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```sh
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ffmpeg -n -i input.mp4 -vf 'scale=1280:-2' -ar 48000 output.mp4
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```
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## Overlay a second input
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```sh
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ffmpeg -n -i video.mp4 -i logo.png \
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-filter_complex '[0:v][1:v]overlay=20:20[v]' \
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-map '[v]' -map 0:a:0 -c:v libx264 -c:a copy output.mp4
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```
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## Fast exploratory cut
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```sh
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ffmpeg -n -ss 00:01:00 -i input.mp4 -t 00:00:20 -c copy cut.mp4
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```
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## Extract audio
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```sh
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ffmpeg -n -i input.mp4 -map 0:a:0 -vn -c:a flac output.flac
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```
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## Generate a synthetic test asset
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```sh
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ffmpeg -f lavfi -i 'testsrc2=size=320x180:rate=30' \
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-f lavfi -i 'sine=frequency=440:sample_rate=48000' \
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-t 2 -c:v libx264 -pix_fmt yuv420p -c:a aac test.mp4
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```
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## Diagnostic null output
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```sh
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ffmpeg -hide_banner -loglevel verbose -i input.mp4 -f null -
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```
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## Build-aware filter check
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```sh
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ffmpeg -filters | grep -E 'scale|fps|drawtext|subtitles'
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ffmpeg -h filter=scale
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```
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SOURCES (LAYER 3 NAVIGATION)
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https://ffmpeg.org/ffmpeg.html
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-> Primary command syntax, mapping, copy/transcode, seeking, and filtering options.
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https://ffmpeg.org/ffprobe.html
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-> Primary inspection and machine-readable output.
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references/local-verification.md
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-> Commands actually exercised on the local FFmpeg 8.1.2 build.
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