Performance Editing Question

[bbeiler]

I read over the years that buying a second hard drive can greatly increase performance when video editing by placing the temp folder on a physical hard drive seperate from which the program is running. I have found that to be true. My question however, is based on where the captured file should be. More specifically...

I have 2 physical hard drives, I'll call them c and d for simplicity (although I have logical partitions set up d, including one for the paging file). I have installed the video editing program on c with the OS (Nero Vision, DVD moviefactory, movie maker, etc...). I then have moved the temp folder in each of these programs in a folder on the d drive. Where should I have the source file located? I have been capturing (analog video, through the means of s-video) on the c drive- so that would mean it's located with the program but seperate from the temp file. Should I be capturing to the d drive so it would be seperate from the program but now on the same drive as the temp?

Brent

[uxbridge]

Ideally you should use the fastest drive for capturing.
Editing is much less sensitive.
If you have temp file and destination file in the same disk and partition, then performance might be better, but it depends on the way the application handle temporary files.

Use Vdub to check performance of your disks and then do capturing, editing and temp file on the one with best performance.

Ciao

[bbeiler]

capturing really hasn't been an issue for me. I have a hardware mpeg-2 encoder, which to my knowledge has very little or even no dropped frames. They might be some, but it has never been visually noticed nor does my capturing program indicate any.

If I already have an mpeg file (captured as described earlier), and I add/import it into an editing program, and let's say I add text and maybe an audio track to the mpeg file and some other minor cuts and paste. I then output it to a DVD-Video compliant DVD. When it does it's transcoding I would assume it stores it in the temp folder then outputs it to the disk. I guess I could directly store it do a folder and that is what you mean by destination folder. Then I could burn a DVD-Video compliant disk later. Or do you just mean saving the project?

Both my hard drives are pretty fast. My c: drive is an SATAII 80 gig dell original (I couldn't find specific specs, but my bios shows up as 3.0gb transfer) and my second is a SATA I 300gig 16MB cache Maxtor.

I'm just trying to prevent reading/writing on the same disk at the same time.

Brent

[uxbridge]

To provide an answer it would mean understanding how your specific application handles temporary files. I do not know.

In general You should not be bothered about reading and writing on a single disk at the same time unless you are doing real-time jobs such as capturing. Your Operating System is just made to cope with issues like that.

Also the specs of your disks would suggest you have fast system and fast devices, that means little need for optimization.

Ciao

[redwudz]

What uxbridge said. One of the main reasons I usually advise a second drive is that the boot drive is continually being accessed by the OS for 'housekeeping' chores. This is not really a big problem when editing and encoding, but it can be when capturing a realtime video stream.

I use four drives on my encoding computer: Boot, Edit, Archive and Backup. (For program storage and OS backup) Probably overkill, but I only use single partitions on each of the drives. Multiple partitions don't help performance much if they are all on the same drive. Being able to run the files back and forth between two non-OS drives works well for me.

[edDV]

Assuming a program like Premiere and DV or uncompressed capture, it is desirable to have the tmp files (aka scratch disk) and capture file on the second drive. This isolates the capture from OS disk activity.

The editor will first capture to the temp buffer and when done "copy" to the capture file. If they are on the same drive, the temp file is just renamed. If they are on separate drives, there needs to be an actual disk to disk copy that is much slower.

When cuts editing, you are just operating on a database. The capture files aren't touched until you export.

If you are filtering or doing transitions, the capture file must be conformed to the internal processing standard of the editor which may be uncompressed RGB or YUV for those areas of the file that needs to be processed. This would require accessing the file, processing a temp file and then processing the effect to another temp file. Usually the CPU is running much slower than disk access at this point but you might be able to argue having the capture file on a third drive might speed the read/write.

In order to optimize, you would need to understand the internal workings of the program.

During encoding, segments of the capture files and temp files are accessed sequentially and processed into more intermediate files. This step is so CPU intensive that disk optimization probably has minimal advantage.

All this would be very different if you were working with hardware realtime effects cards that need up to 4 realtime streams to process an effect.

In your case, you are hardware capturing to MPeg2 which is low bitrate. In that case the second drive has less advantage for capture, but still has advantage for temp files to keep editor functions from losing HDD priority. For example, you see this on laptops when scrubbing on the timeline. If the OS takes the drive you get jerky scrubs.

Capture to MPeg can slow editor and encode processing since the MPeg file needs to be decompressed for any timeline processing. This could result in creation of huge temp files for those clips dragged to the timeline.