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Last Updated: 2026-08-27 07:36:09

Common Output Options

General FFmpeg Usage

Common Output Options

OptionDescription
-c:vVideo encoder; copy copies the stream directly
-c:aAudio encoder
-b:v / -b:aTarget video or audio bitrate
-maxrateMaximum video bitrate constraint
-bufsizeRate-control buffer size
-rOutput frame rate
-gGOP length, or keyframe interval
-pix_fmtOutput pixel format
-arAudio sample rate
-acNumber of audio channels
-movflags +faststartMove the MP4 index to the beginning for progressive web playback

Create an MP4 suitable for web playback:

ffmpeg \
  -i input.mp4 \
  -c:v libx264 \
  -crf 23 \
  -c:a aac \
  -movflags +faststart \
  output-web.mp4

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