[FFmpeg-devel] H.263 packetizing into RTP

[Martin Storsjö]

On Mon, 6 Apr 2009, Michael Niedermayer wrote:

> > +            while (p > buf1) {
> > +                if (p[0] == 0 && p[1] == 0) {
> > +                    /* Found a byte aligned startcode. */
> > +                    len = p - buf1;
> > +                    break;
> > +                }
> > +                p--;
> > +            }
> 
> this can be done a little faster by steping by 2 and only checking the
> surounding bytes when the middle one is 0
> basically, using ff_h263_find_resync_marker() should achive that

Ah, clever!

I implemented two different alternatives of this; one searching forward 
using ff_h263_find_resync_marker and uses the last one found, the other 
alternative uses a local reimplementation of the function searching in 
reverse direction, which is potentially a bit more efficient since it 
doesn't necessarily have to search through the whole frame each time.

Which one of these do you prefer?

// Martin
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