Hello to all. I'm a libav beginner and I'm working at video capture project.
I'm learning ffmpeg based on this tutorial: http://www.dranger.com/ffmpeg/ So now I need to get images from webcam (v4l2), and I'm using these instructions: AVInputFormat *iFmt = av_find_input_format("video4linux2"); AVFormatContext *pFormatCtx; When I open the video av_open_input_file(&pFormatCtx,"/dev/video0",iFmt,0,NULL); this message is printed on screen: [video4linux2 @ 0x19c6010]Estimating duration from bitrate, this may be inaccurate And the dump data show stream with negative bitrate (-2147483). This is the dump_format() output: Input #0, video4linux2, from '/dev/video0': Duration: N/A, start: 1275920057.312480, bitrate: -2147483 kb/s Stream #0.0: Video: rawvideo, yuyv422, 320x240, -2147483 kb/s, 1000k tbr, 1000k tbn, 1000k tbc After get the stream, when I start the frame capture loop with av_read_frame, I see that each packet captured is a frame (I don't know if this is the correct behavior) and after 32 frames the programs exit with this error: [video4linux2 @ 0x19c6010]ioctl(VIDIOC_DQBUF): Invalid argument My program doesn't have GUI, and it needs to get frames from camera, encode and store on disk. I tried to read ffmpeg.c and ffplay - which get the bitrate correctly - to learn about libav, but they are very complex (in ffplay there is a mix with libav and sdl, and this dificult my life :-)). So I need to do where can I find a good and updated tutorial or thread on list for libav beginners. For example, who is the "img_convert" replacement? Thanks to all. _______________________________________________ libav-user mailing list [email protected] https://lists.mplayerhq.hu/mailman/listinfo/libav-user
