[MPlayer-dev-eng] Nut, few ideas

[Michael Niedermayer]

Hi

On Tuesday 20 April 2004 15:55, Ivan Kalvachev wrote:
> ok
>
> So, we get some flaming each other.
> Here is summary of my proposals about nut format.
> (not yet finished)
>
> In summary.
> making main header startcode in human readable format.
the 64bit startcodes starts with 'N', x, where x is a human readable letter, 
if u and rich prefer we can change all startcodes to start with 'N','U','T',x
allthough this would mean that there are just 32 random bits left which would 
weaken the error resistance somewhat, IMHO we should leave the current codes
the 264bit (no typo) startcode u propose is a completely unacceptable mess

> add maximum known vlc size limits.
i agree with rich that these are useless 

anyway, i would like to suggest that every proposed change must at absolute 
minimum 
1. fullfill a goal (like improving error resistance, simplify, reduce 
overhead, whatever)
2. this goal must be clearly written down
3. not significantly worsen overhead, error resistance or simplicity
4. (optionally) spec& implementation patch + filesize/error resistance 
statistics

>
> For now I keep the checksum at the end. But I don't like it.
ok, ill explain it to u again, the checksum must be at the end because when 
the packet doesnt fit in memory it would require seeking back, it also 
sometimes simplifies decoding (calculating the crc of the data with the crc 
checksum appended at the end gives 0 if its undamaged) ok we use the adler32 
checksum which doesnt have this property ...

> As packet headers are written in memory buffers it doesn't really
> matter.
>
> Removing frame_code compression and using another flag scheme.
iam not against this in principle, but as rich said it must not worsen the 
overhead by a significant amount

[...]
-- 
Michael
level[i]= get_vlc(); i+=get_vlc();		(violates patent EP0266049)
median(mv[y-1][x], mv[y][x-1], mv[y+1][x+1]);	(violates patent #5,905,535)
buf[i]= qp - buf[i-1];				(violates patent #?)
for more examples, see http://mplayerhq.hu/~michael/patent.html
stop it, see http://petition.eurolinux.org & http://petition.ffii.org/eubsa/en