Filtering video and adding metadata in one step failed

Question

I want to filter a video stream

-vf crop=300:ih,mpdecimate

and add metadata for it to the output video:

-metadata:s:v:0 rotate=90

This command filter it, but the metadata are NOT added:

ffmpeg -to 6 -i input.3gp -vf crop=300:ih,mpdecimate \
       -metadata:s:v:0 rotate=90 \
        output.mp4

But I do the same in 2 steps (using a temporary output as input),
the result is OK, the metadata ARE added:

ffmpeg -to 6 -i input.3gp -vf crop=300:ih,mpdecimate \
       temp.mp4

ffmpeg -i temp.mp4 -c copy \
       -metadata:s:v:0 rotate=90 \
        output.mp4

My question is:

Is it impossible to filter a video and add some metadata in one step?

---

Part of FFprobe output:

For the successful 2-steps method:

    Metadata:
      handler_name    : Core Media Video
      vendor_id       : [0][0][0][0]
    Side data:
      displaymatrix: rotation of 90.00 degrees

For the 1-step method, the last 2 rows are missing.

Answer 1

Yes, the rotate tag is ignored for encoded video streams.

Should be patched in git master within a couple of days.