Audio dB overlay on video

[Stefan Sauer]

On 09/16/2015 12:51 PM, Baby Octopus wrote:
> Hi,
>
> I'm looking to overlay the audio's dB over video, something like the
> following pipeline
>
> gst-launch-1.0 v4l2src ! videoconvert ! audiooverlay ! autovideosink alsasrc
> ! level ! fakesink
>
> Here the level element will post messages in bus which the audiooverlay
> element needs to read this msg and overlay the graphics(something like
> http://www.djfrankieb.net/AudioStereoLoudnessVUMeter.gif)
>
> Any suggestion is highly appreciated :)
>
> ~BO
We don't have such an element. Applications usually handle the element
messages from the bus and update a level-meter widget.
Ofcourse it would be possible to have an element that overlays the
vu-meter gfx on top of the video. I think this would be too specialized.
The element would duplicate a lot of the videomixer code, it would need
a bunch of parameters to place the vu-meter.
The main issues is that the vlevel-meter-overlay element would not be
able to read the level bus message. Even if level would send the message
as a sink-event, it would only travel to the audio sink.

Stefan