MSP preview vs avi playback

[Bruno]

I still have a lot of problems with jerky playback of video files. I doesn't matter whether I use PC-VCR, MSP ''create video'' , whether it are just captured clips or rendered avi files; the playback varies from occasionally jerky to very jerky (sometimes the playback freezes for more than a second before continuing (audio continues to playback smoothly).
However when I play a project using the ''best preview'' directly from MSP it is always perfectly smooth, without any exception. When I select ''active movie player'' instead of ''best preview'', the ''jerkiness'' is back.
I was planning on installing a second harddrive to solve my playback problems, but I have trouble understanding how the HD could cause a problem for playingback a singel AVI file while it has no trouble at all as a preview from the editor.
Does anyone know what the differences are and how they could explain the different playback performance, because this may give me a hint in solving the problem. I'm sure the clips are captured properly because parts that playback jerky one time may be smooth the next time and vice versa.
I currently avoid the problem by outputting the projects to VCR previewing from the editor, but it would be nice to be able to playback clips smoothly as well.

[DrMordrid]

Bruno,

From your posts it appears you are only using a single drive. THIS WILL NOT WORK.

Your videos have to be captured to, and played back from, a separate drive from your system drive. Otherwise when the swapfile is read or written to your captures and playbacks WILL stutter. This drive should also NOT be on the same cable with the boot drive. It MUST be on a separate channel or controller from the system drive.

While those system tweaks you are considering will help properly set up systems they will not help this issue. Only a separate capture drive will help that.

When you pick that drive get the largest one you can afford. Maxtor has a couple of new ones that store 40 gigs: DiamondMax 40 (5400 rpm) and DiamondMax Plus 40 (7,200 rpm).

Dr. Mordrid


[This message has been edited by DrMordrid (edited 05 January 2000).]

[Brian Ellis]

Bruno

Almost certainly a combination of hardware and config. You really need a dedicated fast, freshly formatted, hard disk, working on DMA, to play back files smoothly. Many aspects of this problem have been dealt with in detail over the past months: why don't you browse backwards to learn about them? Also look in the FAQs of 'This Idiot's' excellent site.

If re-posting here, we need to know your H/W, S/W and config to comment well????



------------------
Brian (the terrible)

[Bruno]

I have a PII 350, 64Mb, 13GB EIDE Drive (DMA eanbled), Marvel G200, Turtle Beach Montego sound card.

Over the last months I have tried (so far without success) all the suggestions I have found in previous treads, tips & trics, FAQ’s, etc, with the exception of installing a dedicated hard drive. However, before spending money on it I’m trying to understand why playback from the cutlist never causes a problem while playing the AVI files from MSP,Avid or PC-VCR consistently gives problems. It the problem was the hard disk performance, I wouldn’t expect such a difference, or am I missing something?

One other thing I’m going to try tonigth is limiting the Vcache using Cacheman (based on DrMordrid’s tread).

[smitty]

Hi.You didn't mention what your capture was from.Does this occur only with clips captured from the same source?
I had a similar problem with some clips captured from a certain camcorder which I believe had a problem with sync.It seems the camcorder could playback ok, however when I captured the clip(s),something lost sync and I dropped some frames on capture.Did you drop any frames on capture?

[Bruno]

I do have indeed only a single drive and will install a second one, I will need it for storage space anyway. I also realise that it is the only proper way to avoid problems on capture and playback. It's just that I'm puzzled about the big difference in playback smoothness for preview vs regular playback. I would think the same amount of data is read from the drive in both cases, only the program must be doing it in other ways resulting in a big difference in performance. It's probably my curiosity but I would really like to understand why this is so different.
By the way, I limited the diskcache by running cacheman and it seem to have solved the problem for at least 90%. Playback from PC-VCR is perfectly smooth (so far). Playback from MSP has improved significantly. Thanks a lot for that suggestion!

Smitty,
I usually have no dropped frames (when I take the proper precautions, defrag etc.). I only capture form a single Hi8 camera and a VHS VCR. Results are the same. I even have (had) the playback problem with the demo AVI files supplied by AVI cinema, and I suppose these were captured properly.