MPEG2Dec3 v1.10

[trbarry]

Yes - BSR is VectorPath, and executes in at least 10 cycles. Furthermore the code isn't pairable at all, leaving 2 of the three pipes unused.

Sh0dan -

I don't know what VectorPath is, but I assume it's costly from the rest of it.

What do you think of requiring SSE instead of SSEMMX for those 2 functions of mine that need bsr? That should eliminate the Athlon's but accept P3 & P4. And it's a one line change.

- Tom

[sh0dan]

VectorPath is AMD's word for complex "emulated" instructions, that usually requires several cycles to decode and execute.

Nic's Athlon XP has SSE, so it will be used there.
It is however impressive that the "if" code can execute faster than the assembler.

[trbarry]

It is however impressive that the "if" code can execute faster than the assembler.

It's more than impressive. It's totally frelling mind boggling. But it is true that the if/else logic usually falls out after the first 1 or 2 tests on normal data, so it's nowhere near as bad as it looks.

- Tom

[Nic]

Ok, I released 1.06 for now. (releasing it as 1.05 might have caused confusion)

@Tom: Has your block decoding optimisations for sse2 only for now, hope thats ok.

All seem good to you?

-Nic

[DDogg]

mpeg2source("D:\mymovie.D2V",idct=6) returns:

MPEG2Source:IDCT invalid(1:mmx,2:SSEMMX,3:FPU,4:REF;5:SSE2)

[AmiRage]

Originally posted by DDogg
mpeg2source("D:\mymovie.D2V",idct=6) returns:

MPEG2Source:IDCT invalid(1:mmx,2:SSEMMX,3:FPU,4:REF;5:SSE2)

Same here for idct=7 also.

[cult]

where is it?I cant see any attachment

[ARDA]

First post of this thread

Arda

[Nic]

Sorry didn't check marcfd's override param, I always change it in the d2v...ill go ammend that now..

-Nic

edit:
Ok, that bugs fixed, please re-download:
(updated links always at start of thread)
http://nic.dnsalias.com/MPEG2Dec3v106.zip

SourceCode:
http://nic.dnsalias.com/MPEG2Dec3v106_src.zip

pps
BTW: Skal's iDCT is faster, but only slightly, you may not notice a difference, but its the fastest iDCT ive ever seen, so its included for completeness

[HarryM]

Originally posted by Nic
pps
BTW: Skal's iDCT is faster, but only slightly, you may not notice a difference, but its the fastest iDCT ive ever seen, so its included for completeness [/B]

@Nic: Can you add Skal's code into your MpegDecoder?

[lighty]

Originally posted by HarryM
@Nic: Can you add Skal's code into your MpegDecoder?

AFAIK- he already did include it as he said in the previous post.

[Ctrl-Alt-Suppr]

Skal's iDCT is faster
Are you sure ?

DVD zone2 : BLADE ( 3 min ) ~ Asus P4G8x ~ P4 2.53°2.89 ~ 512mo
AviSynth 2.51 RC4 ~ Xvid's Koepi 14/05/2003 ~ VDubMOD 1.4.13 v2 (for debug .log)

MPEG2Source("D:\...\.d2v",idct=X ).Crop(4,72,-8,-76).Trim(99500,104000)
BicubicResize(608,256,0,0.5)

idct=1 ___ 83 sec ___ 54.22 fps ___ 34.9 mo
idct=2 ___ 82 sec ___ 54.88 fps ___ 34.9 mo
idct=3 ___ 89 sec ___ 50.56 fps ___ 34.9 mo
idct=4 ___ 133 sec ___ 33.83 fps ____ 35 mo
idct=5 ___ 80 sec ___ 56.25 fps ___ 34.9 mo
idct=6 ___ 82 sec ___ 54.88 fps ___ 34.9 mo
idct=7 ___ 86 sec ___ 52.33 fps ___ 34.9 mo

[HarryM]

Originally posted by Ctrl-Alt-Suppr
Skal's iDCT is faster
Are you sure ?

DVD zone2 : BLADE ( 3 min ) ~ Asus P4G8x ~ P4 2.53°2.89 ~ 512mo
AviSynth 2.51 RC4 ~ Xvid's Koepi 14/05/2003 ~ VDubMOD 1.4.13 v2 (for debug .log)

MPEG2Source("D:\...\.d2v",idct=X ).Crop(4,72,-8,-76).Trim(99500,104000)
BicubicResize(608,256,0,0.5)

idct=1 ___ 83 sec ___ 54.22 fps ___ 34.9 mo
idct=2 ___ 82 sec ___ 54.88 fps ___ 34.9 mo
idct=3 ___ 89 sec ___ 50.56 fps ___ 34.9 mo
idct=4 ___ 133 sec ___ 33.83 fps ____ 35 mo
idct=5 ___ 80 sec ___ 56.25 fps ___ 34.9 mo
idct=6 ___ 82 sec ___ 54.88 fps ___ 34.9 mo
idct=7 ___ 86 sec ___ 52.33 fps ___ 34.9 mo

You have SSE2.
I have AthlonXP and idct=6 (Skal's SSEMMX) is about +2% really faster than idct=2 (SSEMMX) for me.
Of course - without Crop, Trim, etc. and with 'null - test speed' in xvid.

[HarryM]

@Nic:

Skal's SSEMMX idct is more accurate than FPU 64bit idct?

we need someone with a 64bits processor

[JohnMK]

Is there a way to force an idct by placement of some kind of overriding text file with your preferred idct in the same dir as mpeg2dec3? I don't like the idea of tinkering with my .d2v, I'd rather have an automated solution for the future. The older versions used to have this feature . . . .

[HarryM]

Originally posted by JohnMK
Is there a way to force an idct by placement of some kind of overriding text file with your preferred idct in the same dir as mpeg2dec3? I don't like the idea of tinkering with my .d2v, I'd rather have an automated solution for the future. The older versions used to have this feature . . . .

Mpeg2Source("...", idct=6)

[Nic]

@ctrl-alt-supr: "Are you sure?"
I did write for a reason:
"Skal's iDCT is faster, but only slightly, you may not notice a difference, but its the fastest iDCT ive ever seen, so its included for completenes."

And yes I am sure.

-Nic

[killingspree]

wow... you got me confused now (:
what's supposed to be faster on a PIV now? idct=5 or 6?

regards
steVe

[Nic]

@killingspree: Hmmm, 5 (SSE2) probably will be, for now I wouldn't start using 6. The speed difference is small and I havent tested it fully yet.

(when I tested it, I just left it doing random iDCTs and comparing it to other iDCTs, and it is faster, but it seems in MPEG-2 Decoding it doesnt make any real difference, still its there for completeness, ill test its accuracy properly soon)

-Nic

ps
Im almost tempted to use 7 (simpleidct) myself...even though tests have shown that iDCT accuracy doesn't seem to make any real kind of a difference to the eye when mpeg-2 decoding, maybe it will make a difference to the encoder (even if very very tiny)...Hmmm, I may have to check.