AC3 rendering... can someone PLEASE explain

DJPadre wrote on 2/25/2008, 7:35 PM
Why it takes over 3x longer to render an AC3 5.1 file using a quad core?

On my single core, i at least got realtime rendering.. 1hr would take an hour to process...
Now though, 1 hour takes 2.5hrs

Video is faster.. hell im rendering 1080i HDV down to 720p as it renders ac3, but it seems to me, that my single core 3.0ghz was used in its full capacity whereas now, only a single 2.4gh core is used.. so im losing 600mhz speed on non multicore plugs/codecs

WHy oh why oh why oh why isnt ac3 rendering multithreaded? Its funny.. SCS lead us to beleive that V7/V8 is multithreaded.. when in fact only parts of it are... Hell its been like this since V6

REALLY geting sick of sticking up for Vegas then to be dissappointed over and over again like this...

Comments

DJPadre wrote on 2/25/2008, 7:48 PM
I mean, COME ON!!!

How many revisions do we need to go through before this program is optimised?
V6 was supposed to be the bes knees...

How many fixes etc do we need to download jstu to get the bastard working the way we want it to ?

I mean seriously, the filters are sorely in need of a reqork, the "engine' needs reqorking to take advantage of technology today... previewing is a joke, i mean to get decent DV previews, you gotta set up a 720p project, only THEN will the app juice more grunt into the preview engine coz its scaling... theoretically this shouldnt be the case but its the only way to get half decent previews...
FFS, thers stioll no auto WB filter, theres still no colour match filter, theres still no prgressive scan support (as in PROPER support).. if u think it does support progressive, go run a slowmotion on progressive footage and get back to me...
They still havent fixed the pan crop reframe slowmo issue.. (pan and crop a clip (interlace or progressive) then run slowmo and see what im talkin about)

like i said, im getting really sick and tired of having to work around vegas' limitations.. its wasting my time.

U know who i blame?
I blame the Beta testers who dont pick this shit up when they shoudl be. I also blame the hed honchos who dont think its important enough to fix. i also balme the engineers who stick this in the too hard basket.. i mean CMON, how can anyone exaplin why progressive footage is interlaced for processing? Why am i seeing Interlace banding/combing on native progressive footage?
Why is my unporcessed progressive footage seen as 50i which 50i cadeance? because vegas bloody wel converts it to 50i (as opposed to using a 2:2 pulldown AS IT SHOULD even though i dont want it to...

AAAAAAAARRRRRRRGHHHHHHHHHHHHHHHHH!!!!!!!!!!!!!!!!!!!

Rant over...
farss wrote on 2/25/2008, 8:47 PM
If you put as more energy into thinking and less into ranting you might find the answers to many of your questions :)

i mean CMON, how can anyone exaplin why progressive footage is interlaced for processing? "

You cannot make progressive footage into interlaced, if Vegas can do this it should cost a lot more. Do you understand the difference between 25P and 25PsF. There's almost nothing that does 25p, it's all 25PsF.

Which camera are you using?
Are the clips flagged as progressive, check on the T/L, many times the flags are missing or misread. Seems to work OK with the V1 at least.

Bob.
DJPadre wrote on 2/25/2008, 8:56 PM
well its sure as hell doing a good job of interlacing progressive footage...

as for 25p and 25psf, i do know hte difference, however its funny how this was never an issue when the DVX was first released.

As for the issues, vegas picks up progressive tags from the DVX without an isue.. its processing this progressive footage which has ALWAYS been a problem
IM also using an A1's but im primarily shooting in 1080i so its a no brainer with that one..

As for 16:9 and progressive, manyu a tim does vegas misread a huffy YUV file, throwing it into upper field and stanrds sq PAR, so ive had to go in and manually set it.
I dont mind this, what i DO mnd is when vegas pukes my perfectly good progressive footage...

Thres still the issue of AC3 rendering.. my rant came from the ridiculous time ive waited for the bloody thing to render
John_Cline wrote on 2/25/2008, 9:20 PM
"like i said, im getting really sick and tired of having to work around vegas' limitations.. its wasting my time."

Then I suggest you go buy a copy of Premiere immediately and leave Vegas to those of us that aren't having any problems with it.
farss wrote on 2/25/2008, 9:25 PM
One tip from the local Vegas trainer. It will not run on a quad core.
Make of that what you will.

Bob.
DJPadre wrote on 2/25/2008, 9:26 PM
so u think that single core rendering of ac3 is acceptable when i can render hd at the same time and get faster results?

explain to me then how i can justify selling this tool to editors when these basic problems continue to exist?
owlsroost wrote on 2/26/2008, 1:29 AM
DJ,

I don't understand why your AC3 rendering is so slow....

Using a simple project (1 video +1 audio track) 'upmixed' to 5.1 using a small collection of VST plug-ins, I render to 5.1 at about 2.5x faster than realtime (1 hour takes about 25 mins to render using the AC3 Pro codec) on a 3.2GHz dual-core P4.

Windows Task Manager shows about 55% CPU usage during AC3 rendering - I agree with you that it should be more multi-threaded.....

I haven't tried AC3 rendering on the 2GHz Core 2 Duo laptop I'm writing this on, but on every other performance comparison I've done(with the 3.2 GHz PC above) the laptop is considerably faster....

Are you sure your quad-core hardware is running properly - does something like CPU-Z show 4 cores running at the correct clock rate etc?

Tony
TheHappyFriar wrote on 2/26/2008, 7:08 AM
while it's not using 100% of the core speed, on my Quad core AC3 5.1 is DEFINETLY using all four cores. Core 0, 1 & 3 are all ~25% while Core 2 is at 50%. When the rendering stops it all goes to 0-2%.
DJPadre wrote on 2/26/2008, 8:48 AM
Friar, each CPU clocks at 25%, but its still slwo as buggery..
I dont know what it is.. whether its a plugin or what have you.. ive tried goign nude (no plugins) but still its as slow as buggery...

as for the system, everything else runs perfect (knock on wood)
sean@oregonsound.com wrote on 2/26/2008, 9:41 AM
"One tip from the local Vegas trainer. It will not run on a quad core.
Make of that what you will."

What?? Did he mean Vegas won't run on a quad core? What the heck is that supposed to mean?
R0cky wrote on 2/26/2008, 9:54 AM
Rendering to MPEG on my quad core pegs the needle at 100%, that is, all for cores are maxed out, as long as you don't have single threaded FX you're processing. Neat Video seems to be single threaded, as are the Pixelan effects.

I think the media generator, at least the old title gen is also single threaded.

rocky
TheHappyFriar wrote on 2/26/2008, 9:56 AM
it might not matter, but I have an AMD Phenon 9600. What type of video card do you have? I don't think there's a connection, but many people who play games have bad luck with using Intel multi-core and nvidia on the same system. Many have issues with just Intel multi-core's. Normally requires disabling a thread in the software to force it single core, changing a tweak in the nvidia control panel, something along those lines. But I do know people who play games have issues with Intel mutli-core's.
Kennymusicman wrote on 2/26/2008, 4:59 PM
In relation to the original post, and a little bit with regards to the last...

A 1hr 53m 7s feature, in full surround, rendered into AC3 Pro surround, took 17m29s, whilst using 33% average of all 4 cores on my Intel Q6600, which features and NVidia 8600 GPU, with no tweaking.

TheHappyFriar wrote on 2/26/2008, 6:31 PM
eliminates any intel threading + gpu issues (it happens to every person who uses an intel multi-core & nvidia card).

I don't believe any sound render has ever peaked the CPU usage, has it? I don't recall any.