blob: 9f0c56bb8b861da39ebb1aee6459a139e3b75df7 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
|
# ffmpeg (1)
## screen capture specific window (x11)
Following snippet allows to select a window which is then captured.
```bash
#!/bin/bash
echo "Click on window to record .."
# Extract window size and x,y offset.
video_args=$(xwininfo \
| awk '/Absolute upper-left X:/ { xoff = $4 }
/Absolute upper-left Y:/ { yoff=$4 }
/Width:/ { if ($2 % 2 == 1) { width=$2-1; } else { width=$2; } }
/Height:/ { if ($2 % 2 == 1) { height=$2-1; } else { height=$2; } }
END { printf "-video_size %dx%d -i :0.0+%d,%d", width, height, xoff, yoff }')
ffmpeg -framerate 25 -f x11grab $video_args -pix_fmt yuv420p $@ output.mp4
```
> Use `yuv420p` pixel format if video is played on the web
> ([ref](https://stackoverflow.com/questions/32829514/which-pixel-format-for-web-mp4-video))
The input `-i 0,0+xoff,yoff` means to capture `$DISPLAY=0.0` starting at the
coordinate `(xoff, yoff)`, which is the left-upper corner, and the size of the
capture is defined by the `-video_size` argument.
|
