Re[2]: [XviD-devel] scene change detecting in Bframes mode

[Christoph Lampert]

On Tue, 20 Aug 2002, peter ross wrote:

> >I frames are smaller because they use predictions of DCT coefficients
> >between macroblocks, while in P frame all blocks are independant. (OK
> >I might be wrong here, please correct me).
> 
> syskin, i think you've got I-frames and P-frames mixed up.

No, he didn't. He just talks about INTRA blocks. A P-frames full of
INTRA-blocks is larger than a I-frame full of the same INTRA-blocks,
because in I-frames there's AC/DC prediciton between blocks and for
P-frames, there is not. 
That why it's better to use I-frames if the amount of INTRA blocks gets
too large. 


gruel

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