增加录制视频ffmpeg中的fps

Question

I need to record 2 videos from 2 cameras in full hd 30 fps. I use ffmpeg and wrapper - Aforge for c#.

init device:

        _videoCaptureDevice = new VideoCaptureDevice(deviceName);
        _videoCaptureDevice.VideoResolution = _videoCaptureDevice.VideoCapabilities[0];
        _videoCaptureDevice.DesiredFrameRate = _fps;
        _videoSourcePlayer.VideoSource = _videoCaptureDevice;
        _videoCaptureDevice.NewFrame += _videoCaptureDevice_NewFrame;
        _videoSourcePlayer.Start();

saving frames

        if (_videoRecordStatus == VideoRecordStatus.Recording)
        {
            _videoFileWriter.WriteVideoFrame(eventArgs.Frame);
        }

and init file writer

            _videoFileWriter = new VideoFileWriter();
            _videoFileWriter.Open(_fileName, _videoCaptureDevice.VideoResolution.FrameSize.Width,
                _videoCaptureDevice.VideoResolution.FrameSize.Height, 30, VideoCodec.MPEG4, 10 * 1000 * 1000);

now _videoCaptureDevice.VideoResolution.FrameSize equals 1280x720 and 640x480 (for second device). But I already have problems with recording. Maximum fps is 24 for 480p and 13-14 for 720p (when I try to record videos from 2 cameras in the same time)

How to increase it? Or it isn't possible? Maybe more powerfull computer will solve this problem (I have Pentium(R) Dual-Core CPU 2.50Ghz and usual videocart (Geforse 8500 GT) for working with two displays, usual hdd, usb 2.0)?

I will glad any help (maybe another library, but not language (c#))

PS I already used Emgu.CV and faced with simular problems..

Answer 1

The framerate is limited by the hardware.

Use AMCap or GraphEdit to check what your camera really supports. It will depend on the choosen resolution and ouput format (higher resolution -> lower framerater).

Be aware that AForge always uses the highest value for all resolutions which can lead to oversampling (eg: AForge produces the rames at 60Hz, but the camera only supports 15Hz at the given resolution, so the images will mostly be duplicates. See here

Also use process explorer and a profiler to see how busy your CPU really is and what it is doing.