theora - Nov 2008 - ogg_stream_pageout function...

I write this small piece of code, that get pixels and encode them:

    ogg_page       page;
    ogg_packet     packet;

    m_frameSource.getYUVBits(m_buffer.y, m_buffer.u, m_buffer.v);

    theora_encode_YUVin(&m_encoder, &m_buffer);

    while(theora_encode_packetout(&m_encoder, isLastFrame, &packet))
        ogg_stream_packetin(&m_oggStream, &packet);

    while (ogg_stream_pageout(&m_oggStream, &page))
    {
        fwrite(page.header,page.header_len, 1, m_oggFile);
        fwrite(page.body,page.body_len, 1, m_oggFile);
    }

This piece of code runs in real-time. I want to remove the last while block
and save theora packets directly to a temporary file. Then when capture is
finished I read packets from temp file and send them to ogg_stream_pageout.
Does this solution improve performance?
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On 30-Nov-08, at 1:25 PM, Andrea Fontana wrote:
> This piece of code runs in real-time. I want to remove the last  
> while block and save theora packets directly to a temporary file.  
> Then when capture is finished I read packets from temp file and  
> send them to ogg_stream_pageout. Does this solution improve  
> performance?
I wouldn't expect it to affect performance. Ogg encapsulation is  
fairly cheap, and the memcpy()s it requires will be much faster than  
writing the data in either form to disk.

If your video is small (packets often < 4 KB) writing out a packet at  
a time may spread the disk access more evenly, if that helps.

Have you tried setting TH_ENCCTL_SET_SPLEVEL to 2? In the 1.0 encoder  
this trades some quality/bitrate for performance, and is intended for  
constrained realtime applications.

  -r