[FFmpeg-user] no such filter

[Moritz Barsnick]

On Fri, May 22, 2015 at 11:38:44 +0200, lorenzo angeli wrote:
> thanks for the explanation, out of curiosity, do you think is better use
> 'null' or 'copy' for doing nothing ?
> (kind of a weird question I know....)

No, I asked myself the same thing.

The documentation says "copy" is for debug. So I would conclude
"[a]null" is more correct to use. Looking at the source code, I believe
that "null" and "anull" do exactly what you are requesting, i.e.
"connecting" the input to the output, while "copy" goes to the trouble of
copying the frame data, which is at least an additional operation.

Moritz