Dynamic content in qroverlay?

[Thibault Saunier]

Hi,


Since 1.22 the qroverlay supports setting per buffer overlay based on
GstCustomMeta. You can find it mentioned in the documentation:
https://gstreamer.pages.freedesktop.org/-/gstreamer/-/jobs/37354974/artifacts/documentation/qroverlay/qroverlay.html?gi-language=c#qroverlay

In the end this means that instead of trying to set the property in the
probe you should add a `GstQROverlayMeta` on the buffer with the values
specified in the documentation.

Regards,

Thibault

On Thu, 2023-03-02 at 12:38 +0100, Florian Echtler via gstreamer-devel
wrote:
> Hello everyone,
> 
> I've fiddled around with including buffer-specific data in a video
> stream using 
> qroverlay (somewhat like a custom version of debugqroverlay, which
> I'm using for 
> now). I tried the following code snippet:
> 
> # pad probe for debug QR code with timestamp
> def qr_probe_callback(pad,info,pdata):
>      buf = info.get_buffer()
>      parent = pad.get_parent_element()
>      parent.set_property("data",str(buf.pts))
>      return Gst.PadProbeReturn.OK
> 
> [... and afterwards ...]
> 
>      sinkpad = qroverlay.get_static_pad("sink")
>      sinkpad.add_probe(Gst.PadProbeType.BUFFER, qr_probe_callback,
> None)
> 
> The pad probe gets called, but the QR code in the video stream seems
> to be stuck 
> on the very first value that got set when the callback was triggered
> for the 
> first time. What do I need to do to "re-render" the QR code with the
> updated 
> data property?
> 
> Best, Florian
> -- 
> SENT FROM MY DEC VT50 TERMINAL