wrong frames generated by overlay filter when y is negative and dynamic
|Reported by:||Taner Sener||Owned by:|
|Blocking:||Reproduced by developer:||yes|
|Analyzed by developer:||no|
Summary of the bug:
I want to create a vertically moving photo using overlay filter. If I start with a negative y and increase it by time, photo is expected to slide down from the top of the screen slowly. But unfortunately input photo is not rendered correctly and some parts are missing from the photo.
This technique works brilliantly when applied horizontally on x but when y is used this technique fails.
How to reproduce:
Any photo can be used as input.
% ffmpeg \ -loop 1 -i input.jpg \ -f lavfi -i color=black:s=600x600 \ -filter_complex "[0:v]scale=400:400,[1:v]overlay=0:'-h+t/1*600*2',trim=duration=1[video]" \ -map [video] -c:v mpeg4 output.mp4 ffmpeg version N-92590-gf7faaa8c18 Copyright (c) 2000-2018 the FFmpeg developers built with gcc 7 (Ubuntu 7.3.0-27ubuntu1~18.04)
According to my analysis, commit d54014d1573ec6e958e9c9e802e613c73c7f7ba5 breaks something about overlay filter. Test command provided above works on all releases without this commit: 2.8.x, 3.4.x, 4.0.x. But 4.1 and master, which has d54014d1573ec6e958e9c9e802e613c73c7f7ba5, is not working as expected.
Change History (13)
comment:3 by , 4 years ago
|Priority:||normal → important|
|Reproduced by developer:||set|
|Status:||new → open|