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

[Malte Beyer]

Hello,

I am trying to use FFmpeg via the NativeProcess-API in Adobe AIR 2.0. My goal is to encode the video of the webcam with H.264 and stream it to a Flash Media Server. The application will be x-platform (Win and Mac). Additionally I need to switch between different webcams during the live stream.

I already made a small prototype and I nearly managed to stream the webcam to my streaming server. I can send the stream of the webcam to the streaming server when I am using the windows console. I also can communicate with FFmpeg via AIR and I can e.g. send a local video to the streaming server when using AIR.

But I cannot manage it to send the video of the webcam to the streaming server when using AIR. I am using the same command on the command line and in AIR. It works from the command line, but it does not work from AIR.

I am using this command:

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?


Two other questions I was wondering about (probably much easier to answer):

-          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?

-          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?

Thanks for your help.


Malte Beyer
Technical Director
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