[FFmpeg-user] FFmpeg can't get access to webcam when excuted via Adobe AIR?

[Roger Pack]

> ffmpeg -f dshow -i video="Logitech QuickCam E2500":audio="Mikrofon (IDT High Definition A" -f flv rtmp://xyz
>
> As I said it works, when executed via the command line. But when I execute the same command from AIR I get the following error message in my AIR app:
>
> [dshow @ 01998640] Could not find video device.
> video="Logitech QuickCam E2500": Input/output error
>
> The question is: might this be a rights problem? Is it not allowed for FFmpeg to access my webcam when FFmpeg is executed via AIR? And if so, how can I solve it? Or is it some other problem?

Sounds like a rights problem.  Maybe you can specify in AIR
preferences which camera AIR has access to, or maybe...you can access
the raw bytes from the camera through AIR somehow?


> -          I cannot see a solution how to send the video of the webcam to a streaming server on Mac (dshow seems to work just for Windows). Is there no chance to have input via the webcam on Mac? Just Linux and Windows?

I have thought about that recently myself.  I don't think it can yet.
VLC has a qtcapture module, and once it gets working audio capture [1]
I hope to port it over to ffmpeg.


> -          What do you think about switching the cameras during runtime? Is that a problem? Will I stop the dshow-command by sending a "q" and start the next dshow-command with the different cam right after? How will this look like in the frontend? Black screen during the switch?

I believe so. Or rather one window disappears, the next appears.
Related: VLC has an --sout-keep option.  That...might maybe work.
Also I could hack you up a directshow video source device that
presents AviSynth (which has runtime scripts so it can change its
source...I think so anyway), but that would only be for windows so not
sure...

GL.
-r

[1] http://forum.videolan.org/viewtopic.php?f=12&t=89140