Overlay one video on the top of another.
It takes two inputs and has one output. The first input is the "main" video on which the second input is overlaid. This filter requires same memory layout for all the inputs. So, format conversion may be needed.
The filter accepts the following options:
- x
-
Set the x coordinate of the overlaid video on the main video. Default value is
0. - y
-
Set the y coordinate of the overlaid video on the main video. Default value is
0. - w
-
Set the width of the overlaid video on the main video. Default value is the width of input overlay video.
- h
-
Set the height of the overlaid video on the main video. Default value is the height of input overlay video.
- alpha
-
Set blocking detection thresholds. Allowed range is 0.0 to 1.0, it requires an input video with alpha channel. Default value is
0.0.
Examples
-
Overlay an image LOGO at the top-left corner of the INPUT video. Both inputs for this filter are yuv420p format.
-i INPUT -i LOGO -filter_complex "[0:v]hwupload[a], [1:v]format=yuv420p, hwupload[b], [a][b]overlay_vaapi" OUTPUT
-
Overlay an image LOGO at the offset (200, 100) from the top-left corner of the INPUT video. The inputs have same memory layout for color channels, the overlay has additional alpha plane, like INPUT is yuv420p, and the LOGO is yuva420p.
-i INPUT -i LOGO -filter_complex "[0:v]hwupload[a], [1:v]format=yuva420p, hwupload[b], [a][b]overlay_vaapi=x=200:y=100:w=400:h=300:alpha=1.0, hwdownload, format=nv12" OUTPUT