> >
> > 5 mixed_block support
>
> Funny you should mention that. When I was getting bitstream.c
> to work in LAME, i saw that old #ifdef ALLOW_MIXED and thought
> this code is never going to be used and deleted it :-)
> Anyway, it is still in CVS. I dont recall evern seeing *any* encoder
> make use of this: the frame analyzer will display "short (mixed)"
> if the short block is of mixed type.
The Fraunhofer encoders can use mixed blocks.
>
> Of course the fact that I've never seen this may be that the
> frame analizer has a bug in it :-) Does anyone have a mp3
> that they know uses mixed blocks?
>
Yes.
> Some comments: short blocks are used < 10% of the time, and if
> mixed_blocks were used in 10% of those, we are down to a 1%
> effect. If you just allocated more bits these 1% of the cases,
> you would probably get better results and only increase the filesize
> by a tiny ammount.
>
In the Fraunhofer codec it's just a flag the user sets, so that _all_
short blocks will be mixed blocks instead.
> Other problem: what is the algorithm to determine when to use
> a short block instead of a mixed block?
You could try: use mixed blocks, unless there is a surge in energy in
the lowest frequency bands.
Ciao,
Segher
>
>
> Mark
>
> --
> MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
>
--
MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
