[Scummvm-devel] DXA file format for videos
sev at scummvm.org
Sat Apr 29 16:05:01 CEST 2006
On Sat, 29 Apr 2006 17:34:19 +0200
Gregory Montoir <cyx at users.sourceforge.net> wrote:
I tried PNG. It did not work well at all. Maybe because each frame
contains whole palette, maybe because additional format overhead, I
don't know. I didn't try advpng or whatever as that would slow down
BS1: 100MB video (93MB zip archive)
BS2: 187MB video (182MB zip archive)
This is even worse that initial DXA results.
> > Since we don't really need to do seeking, another approach might
> > be interesting, too: For each frame, compute both the result of
> > encoding it as an inter AND as an intra frame. Then use whichever
> > is smaller.
> And that's probably how the original encoder did it as well. If you
> look at some .dxa files, there's often a bunch of intra frames
> following each other in the stream.
Tried that. In short: DXA rocks.
Old results (first is intra frame other are inter):
> BS1: 94MB video
> BS2: 181MB video
BS1: 72MB video
BS2: 146MB video
for comparison. MNG results:
> advmng -S 64 -3
> BS1: 67MB video
> BS2: 136MB video
Taking in account insane complexity and nearly indefinite time to
encode MNG with above options makes DXA an absolute winner.
against Low Q MPEG2:
ZMBV MNG DXA
BS1: 2.9x 2.1x 2.25x
BS2: 6x 5x 5.4x
against High Q MPEG2:
ZMBV MNG DXA
BS1: 1.4x 1x 1x
BS2: 2.3x 1.9x 2.1x
Resulting archives with OGG audio:
So, may we switch to lossless DXA?
More information about the Scummvm-devel