[Libav-user] Decoding a network video stream

[Sergiu Giurgiu]

On 14/08/2019 03:25, Carl Eugen Hoyos wrote:
> Am Di., 13. Aug. 2019 um 20:58 Uhr schrieb Sergiu Giurgiu
> <sergiu.giurgiu at motiongestures.com>:
>
>> I am using libav in a C++ application that acts as a web server. It (the
>> app) provides a websocket endpoint to which a webm video is being
>> streamed by the client, which is a normal browser that accesses the
>> client's webcam. If I save the received data into a file, it can be
>> successfully played by a media player.
>> What I want to do with the data, however, is to extract/decode the video
>> into frames, in a std::vector<cv::Mat> which then will be sent for
>> further processing by some other library. What I was expecting to happen
>> was for the frames that make up the video to be extracted on the fly, as
>> I receive the data.
> This is not possible for all input file formats as in some cases the
> (beginning) of the file is only updated once the encoding has finished.
>
>


I understand that but here we are talking about webm in particular which 
is using a simplified matroska container format and VP8 or VP9 video 
codecs. I presume this has been optimized for the web to allow exactly 
what I'm looking to do, has it not? Both Firefox and Chrome support it 
as far as I can tell.



Replied to you personally earlier, I apologize, didn't have my coffee yet.