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Convert media files between formats - video containers, audio formats, and codec transcoding
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Based on SOC occupation classification
| name | ffmpeg-format-conversion |
| description | Convert media files between formats - video containers, audio formats, and codec transcoding |
Convert media files between different formats and containers.
# Convert container format (re-encode)
ffmpeg -i input.avi output.mp4
# Copy streams without re-encoding (fast, no quality loss)
ffmpeg -i input.mp4 -c copy output.mkv
# Convert with specific codec
ffmpeg -i input.mp4 -c:v libx264 -c:a aac output.mp4
# H.264
ffmpeg -i input.mp4 -c:v libx264 output.mp4
# H.265 (better compression)
ffmpeg -i input.mp4 -c:v libx265 output.mp4
# VP9 (web optimized)
ffmpeg -i input.mp4 -c:v libvpx-vp9 output.webm
# AV1 (modern codec)
ffmpeg -i input.mp4 -c:v libaom-av1 output.mp4
# MP3
ffmpeg -i input.wav -acodec libmp3lame -q:a 2 output.mp3
# AAC
ffmpeg -i input.wav -c:a aac -b:a 192k output.m4a
# Opus (best quality/bitrate)
ffmpeg -i input.wav -c:a libopus -b:a 128k output.opus
# FLAC (lossless)
ffmpeg -i input.wav -c:a flac output.flac
# CRF (Constant Rate Factor) - lower is better quality
ffmpeg -i input.mp4 -c:v libx264 -crf 23 output.mp4
# Bitrate
ffmpeg -i input.mp4 -b:v 2M -b:a 192k output.mp4
# Two-pass encoding (best quality)
ffmpeg -i input.mp4 -c:v libx264 -b:v 2M -pass 1 -f null /dev/null
ffmpeg -i input.mp4 -c:v libx264 -b:v 2M -pass 2 output.mp4
# Encoding speed presets (faster = larger file)
ffmpeg -i input.mp4 -c:v libx264 -preset fast output.mp4
# Options: ultrafast, superfast, veryfast, faster, fast, medium, slow, slower, veryslow
# Quality presets
ffmpeg -i input.mp4 -c:v libx264 -preset slow -crf 18 output.mp4
# Convert all MKV to MP4
for f in *.mkv; do
ffmpeg -i "$f" -c copy "${f%.mkv}.mp4"
done
# Convert with re-encoding
for f in *.avi; do
ffmpeg -i "$f" -c:v libx264 -c:a aac "${f%.avi}.mp4"
done
-c copy when possible for speed (no re-encoding)SkillsBench contribution workflow. Use when: (1) Creating benchmark tasks, (2) Understanding repo structure, (3) Preparing PRs for task submission.
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