[FFmpeg-devel] How to write frames in a memory buffer, instead of a file?

[Michel Bardiaux]

Michel Bardiaux a ?crit :
> Cristiano Belloni a ?crit :
>> Cristiano Belloni wrote:
>>> Hi to all,
>>>
>>> I'm using ffmpeg to encode H263 and MPEG4 videos.
>>>
>>> I take frames from a shared memory buffer, and encode them in a file, 
>>> opening it with the url_fopen() function, and writing on it with 
>>> av_write_frame() after the avcodec_encode_video() call.
>>>
>>> As I' m streaming rtp packets with live555, I'd like to know if it's 
>>> possible to store in a memory buffer the frame I would write on the file 
>>> with the av_write_frame() function I use now.
>>>
>>> And if it's possible, how do you do it? (which functions of the API do 
>>> you use, and how?)
>>>
>>> Thanks to you all,
>>>
>>> Regards,
>>>
>>> Cristiano.
>>>
>>>   
>> I found this thread here: 
>> http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2007-March/024867.html
>>
>> It says:
>>
>>> [...] the suggested method of passing a pointer 
>>> through an url string is probably more robust against libavformat 
>>> internal changes. [...]
>> Is it possible to pass a pointer to a buffer through an url string? And how?
> 
> See 
> http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2006-December/020068.html
> and its followups
> 
>> Also, this page, http://lab.dyne.org/Ffmpeg/UseUrlProtocol, despite 
>> giving an example of the tcp: protocol, names the function
>>
>> url_open_dyn_buf (&format_context -> pb)
>>
>>
>> Is it the way to go? if I open a dynamic buffer and av_write_frame on 
>> it, the frame will be in the dynamic buffer?
> 
> Its another possibility, However, implementing your own protocol gives 
> you more control.
> 
>> Please, help me! :)
>>
>> Thanks,
>>
>> Cristiano.

Ooops, I missed it: wrong list, this belongs on ffmpeg-user!

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Michel Bardiaux
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