使用gstreamer分割/分割视频流

Question

Is there a way to split a video into segments of specified length? Ie 60 minute video into 12x5 mins.

Answer 1

It seems the "official" way to do this without reencoding and without losing frames is using the splitmuxsink element:

For example for a MKV file input:

gst-launch-1.0 filesrc location=input.mkv ! matroskademux ! h264parse ! splitmuxsink location=file%02d.mkv max-size-time=300000000000 muxer=matroskamux

The max-size-time gives the segment length in nanoseconds (sic), so the above value is 5 minutes. Because it cuts on keyframes, the real segment length will not be exactly 5 min but will vary by a few seconds.

Answer 2

Afaik, you will need to develop your own "segmenter". This is similar to what you need to create HTTP Live streaming files. There might be a simpler solution, but here is what I would do:

You can make a relative small program (in python) using multifilesink next-file=buffer (or next-file marker, if segments can't fit in memory).

You'll need to encode or demux your input stream, and mux the stream back. Cut the muxed stream on key-frame when the desired duration is reached, and push the aggregated buffer (or mark a fake key frame, for example, to force sink to create a new file). Reinitialize the muxer (or append muxer streamheader) to get file with correct header than can be played seperately (depending on the muxer).

Answer 3

gnonlin and gnlfilesource are made for this. You will have to transcode the video as part of the process since gstreamer does not have special support for splitting certain formats without transcoding.

See How do I use gstreamer to make an audio clip from a segment of a longer source? for an example of how to make clips from an audio file.

Answer 4

I was able to accomplish something similar using Perl with the GStreamer and GLib bindings. My hack abuses the GStreamer Pipeline state in order to reset the filesink's location. I use a streaming source and hence the reset to zero behavior after set_state('null') is acceptable. You will need to manage the seek position in your source element in order to support proper segmentation.

my $g_pipeline = GStreamer::Pipeline->new('pipeline');
....
my $g_filesink  = GStreamer::ElementFactory->make(filesink  =>  "filesink");
$g_filesink->set(location => $file_name);
...
$g_pipeline->add(..., $g_filesink);

my $delay = 5000; # switch output file at this interval
my $timer = Glib::Timeout->add( $delay, 
  sub {
    $g_pipeline->set_state('null');
    ...
    $g_filesink->set(location=> $next_file_name);
    $g_pipeline->set_state('playing');
  }
);

Answer 5

FFMPEG has a built in segment demuxer.

check the -segment option n the documention.

http://ffmpeg.org/ffmpeg.html#segment