[Ffmpeg-devel] How to retrieve audio or video stream at same timestamp using av_read_frame
Mon May 23 10:42:37 CEST 2005
Keith Mok wrote:
> But some encoder create movie file, with several seconds of movie data,
> then video data.
I assume you mean "audio", not "video"?
> If buffer excess data, will require a lot of memory specially if you
> need to buffer several seconds of the video data in a frame rate of 30 fps.
> Any comment?
Yes, it's going to require some memory... but what else could you do?
P.S. Please don't top-post...
> M?ns Rullg?rd wrote:
>> Keith Mok <ek9852 at yahoo.com.hk> writes:
>>> When I use av_read_frame, I cannot select whether I want audio stream
>>> or video stream data.
>>> It will determine automatically.
>>> And application need to check the stream type after output.
>>> For some movie files, the video data may not be followed immediately
>>> by the audio data. It may hold few tens seconds of video data followed
>>> by audio data.
>>> During real time playback of a movie file, I want to demux the audio
>>> portion data and video portion data at about the same timestamp. The
>>> only way I can get it is to create two seperate instances of
>>> AVFormatContext on the same movie file. This can waste some
>>> resource. Any better idea ?
>> The usual solution is to buffer whatever excess audio or video frames
>> you get until it's time to decode them.
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