putting a square centre of webcam stream

[Olivier Aubert]

On Wed, 2014-02-26 at 07:35 -0800, ertasemre wrote:
> On my embedded linux platform I have 320x240 lcd display and usb webcam. I
> can display my webcam view via "gst-launch -e v4l2src !
> video/x-raw-yuv,width=320,height=240,framerate=30/1 ! ffmpegcolorspace !
> fbdevsink device=/dev/fb0". I want put a square for targetting a barcode
> image. is there any way to put any shape like a square or simple line on
> webcam stream via gstreamer?
With rsvgoverlay:

gst-launch uridecodebin uri=file:/tmp/c.avi ! ffmpegcolorspace ! \
rsvgoverlay fit-to-frame=true data='<svg viewBox="0 0 320 200"> \
<rect fill="#ccc" x="150" y="90" width="20" height="20"></rect></svg>' ! \
ffmpegcolorspace ! autovideosink

The fit-to-frame is not necessary per se since you know the video
resolution, but it will allow the plugin to fit the viewBox to the video
resolution when the resolution is different.

Olivier