Does ffmpeg only re-encode a maximum of 1 times per stream, when you execute any command no matter the number/kinds of operations/flags?

For example very simply I tried:

ffmpeg -i input -r 33 -r 54 output

To see if there was any indication that it did re-encode twice, and the streams seemed to show the same changes as if there was only a single -r flag there.

Given my limited understanding of the information on the official site (I looked through this stuff again: https://ffmpeg.org/ffmpeg.html#toc-Detailed-description) documentation I'm leaning towards the notion that there's only 0-1 re-encodes happening per stream based solely on whether I specify copy or not (outside of errors). Is this the correct understanding of things?

1 Answer 1


Yes, each output stream undergoes, at most, one encoding. If you map an input stream to multiple output files or multiples times in one output file, those count as distinct output streams.

copy must be set as the codec value for an output stream in order to avoid re-encoding it.

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