Problems start()-ing FFmpegFrameGrabber

[David Šabata]

Hello,

I am trying to merge audio with video and am having problems even starting the grabbers. Here's some code I use for audio grabber.

FFmpegFrameGrabber audioGrabber = new FFmpegFrameGrabber(audiofile);

audioGrabber.setFormat("mp4");

audioGrabber.start();

And here's the error which always pops up

W/System.err﹕ com.googlecode.javacv.FrameGrabber$Exception: avformat_open_input() error -1094995529: Could not open input "/storage/emulated/0/somepath...". (Has setFormat() been called?)

W/System.err﹕ at com.googlecode.javacv.FFmpegFrameGrabber.start(FFmpegFrameGrabber.java:338)

W/System.err﹕ at com.javacv.recorder.FFmpegRecorderActivity$AsyncStopRecording.doInBackground(FFmpegRecorderActivity.java:329)

I tried not calling setFormat at all (which I saw in some snippets around the web) and also tried to use various formats I thought of, such as mp3, mp4, aac, flv, 3gp, but nothing worked.

Can you please point me out, what am I doing wrong?

The file does exist, is readable and playable by any player. Also I tried both classic mp3 song and some recording I did earlier by FFmpegRecorder (based on samples/RecordingActivity).

PS. I'm using latest (I suppose) binaries from the web download section.

[David Šabata]

Ok, I figured it out at last. 

The problem was that I was using another audio/video recorders earlier in the app and then was attempting to start a framegrabber sooner, than those objects got released (because of a race condition).

I am not sure why is this happening, probably the native implementation is sharing some objects across recorders and grabbers. The error message is quite misleading though.