View Full Version : Slow playback on windows vista


Sergio Sanchez
August 1st, 2007, 11:15 AM
I just installed vista bussiness and upgraded to Adobe CS3 apps. I installede the last build of Prospect.

I was reviewing some clips in media player, those clips are stored in a 3 disk SATAII RAID 0 array, the thing is they are running very slow, I tried using the fast playback registry tool in the cineform start menu panel but it didnt work.

I felt that the system response in Premiere Pro was slower too.

Is it normal in Vista?... Is something I could do to get a better performance?...

David Newman
August 1st, 2007, 11:19 AM
Don't use mediaplayer 11 under Vista, it use VFW instead of DirectShow for CineForm (I don't know why.) Use Media Player Classic (it is faster and better all round.) http://www.free-codecs.com/download/Media_Player_Classic.htm

John Miller
August 1st, 2007, 11:32 AM
This matches a symptom of the changes to the way Windows handles audio. I came across this during development of one of our DV programs.

By default, DirectShow-based programs use DirectSound for audio. Until Vista, DirectSound provided acceleration a bit like graphics cards do for video. With Vista, Microsoft have effectively done away with it*. To support legacy programs, there is a software-only implementation of DirectSound. This means the CPU has to do all the processing of audio data destined for the soundcard, even if you have the latest and greatest.

I proved this to myself by simply disabling the soundcard. As a result, video played perfectly.

Modern soundcards designed for Vista have an additional type of driver that doesn't have the problem. Unfortunately, you as a user can't tell DirectShow-based program to use that driver model unless the program is aware of the Vista differences and deliberately lets you choose a non-DirectSound driver model for your soundcard. I'm still at PPro1.5.1 and it is on an XP system so I don't know if CS3 can let you choose the driver type. (We built the option into our program to get around the problem.)

If I recall correctly, it is possible to hack the registry. There is an entry for the default audio driver that Windows will use when rendering a DirectShow graph. It points to another entry where you can change it. Of the top of my head, I can't recall exactly which ones and I'm not at my Vista machine to look.

So, anyway, it is likely a Vista thing coupled with CS3 not being aware of the audio differences in Vista.

*According to Microsoft, in earlier versions of Windows, soundcards were the leading cause of BSODs (and I can attest to that!) The drivers were kernel mode which means if the driver does something incorrect, Windows closes down (to protect itself) - the BSOD. The reason given was that the soundcard manufacturers wrote sloppy drivers (again, I can attest to that, too!) The new driver model for Vista takes the driver out of the kernel and into user space. This means if the manufacters continue to write sloppy drivers that crash, they won't bring the whole system done.

That's what Microsoft say, anyway. It makes sense and has nothing to do with DRM(!)

PS: David replied while I was typing mine. David may be able to poo-poo my theory.

Sergio Sanchez
August 1st, 2007, 01:19 PM
David:

I downloaded the Media Player Classic, but the playback speed didnt change.
What else could be causing the issue?

John Miller
August 1st, 2007, 01:27 PM
To troubleshoot the problem, it really would be helpful to disable the soundcard in Control Panel temporarily to see if the playback speed improves.

David Newman
August 1st, 2007, 01:37 PM
Also check what you CPU(s) are going. Are they flat out with the decode or busy doing something else.

Sergio Sanchez
August 1st, 2007, 02:43 PM
I did both, the CPU`s are working at 30% when i playback the clips. I also disabled the soundcard but it didnt speed up.

I will install a different graphics driver to see it that helps.

John Miller
August 1st, 2007, 03:55 PM
30% seems rather high. Are the files AVIs or something more like MPEG?

David Newman
August 1st, 2007, 04:03 PM
Clip playback should not slow until the CPU is 90-100%, are you sure these clip aren't told to play slow or the disk is not providing data fast enough? Speed test your RAID.

Sergio Sanchez
August 1st, 2007, 06:58 PM
I just re-installed vista, I installed a 64bits version just to take advantage of the 8gigs of ram, The Raid is reading data at 200MB/s, and the clip is a 2K 4:4:4 AVI. I installed prospect and playback the file and the playback is exactly the same as in the 32bit version of vista, is playing slower than in my laptop usb harddrive.

This has to be a Vista issue... I think is better to stay in XP...
I used the 64bit version of WinXP once, but i had problems with Premiere Pro 2...

Any one knows how CS3 apps are running in winxp 64?

Sergio Sanchez
August 3rd, 2007, 06:33 PM
I just installed a copy of XP x64, I´ve been playing around with it and Adobe CS3 with prospect, and it runs really fast, the response of the system in Premiere Pro, with 2K clips, is excellent far superior as in the 32bit version.

I didnt have any trouble so far, so i think im going to stay with this OS.

John Miller
August 3rd, 2007, 08:52 PM
I didnt have any trouble so far, so i think im going to stay with this OS.

Good choice! Glad to hear you have a working solution. XP x64 is a great version of Windows and Vista still has too many issues for multimedia work.