[FFmpeg-user] Two video streams generated with map, filter_complex, scale

[Hans Carlson]

On Sat, 21 Jun 2025, Gyan Doshi wrote:

> On 2025-06-21 04:53 am, Hans Carlson via ffmpeg-user wrote:
>>  Was there a change in behavior with regards to the interaction between
>>  map, filter_complex and scale at some point between 4.4.2 and 6.1.2?
>>
>>  To be more precise...  The following command using 6.1.2 generates output
>>  with 2 video streams; one for the original (1920x1080) and one for the
>>  scaled (1280x720):
>
> Read https://ffmpeg.org/ffmpeg.html#Stream-selection-1 especially 
> https://ffmpeg.org/ffmpeg.html#Complex-filtergraphs-1

Thanks... that helps, but it doesn't really explain why it's different in 
4.4.2.  Was this a bug that was fixed?  Or was the behavior intentionally 
changed?

I'm mostly curious more than anything.  I have a perl script that relied 
on the 4.4.2 behavior and I'm pondering the best way to fix it to support 
ffmpeg > 6.1.2.