Convert flv to mov (and deal with ffmpeg’s “incorrect parameters” error)

Goal: Convert a Flash .flv file to .mov on OS X.

I’ve used ffmpeg before and knew this was a good tool for the job, but hadn’t used it in awhile and wasn’t sure I even had the binary installed.


I have MacPorts installed and found the binary under /opt/local/bin. For those looking for an intro to MacPorts and installing ffmpeg, this 2007 post is still useful.

To get to the latest version, just run:

sudo port upgrade ffmpeg

ffmpeg & “incorrect parameters” error

The ffmpeg command I was after was:

ffmpeg -i brain.flv

but that produced the following errors:

Codec is experimental but experimental codecs are not enabled
Error while opening encoder for output stream #0:1 - maybe incorrect parameters such as bit_rate, rate, width or height

There are some mixed messages on how to address the second error, with some tacking on more and more parameters to ffmpeg.

However, the simplest solution that I found was the one that worked. Examining stream #0.1 reveals that it is the audio conversion that’s creating the problem. There’s a parameter to simply copy the audio stream, which does not require any decoding/encoding or parameters:

-c:a copy (ffmpeg documentation on stream copy)

 The final working command is:

ffmpeg -i brain.flv -c:a copy

This ran successfully and eliminated the “codec is experimental” error as well.