Downloading HD Video

[basa10]

as a carry on from the last thread I posted , I have changed the operating system on my computer from XP to Windows 7 and fitted an extra hard drive
but still lose frames at various timings. Anyone have any more ideas on fixing this problem PLEASE

[Ken Berry]

That's not really a good way of proceeding. Now we have to go searching for your last thread to know what kind of video you are talking about, how you are trying to download it, any hardware involved in the download etc, and what connection is involved (e.g. USB, Firewire, SD card etc)...

EDIT: I did the search, and here is the start of that previous thread -- http://forum.corel.com/EN/viewtopic.php ... 53#p282753 But I'm sorry, I personally can't think of anything more you can try...

[Davidk]

A few thoughts on reading this brought to mind a similar situation I once had. A video playback from a USB drive would periodically seem to seize up, and then resume after a few seconds. My experience became focussed on the hardware, and the relative speeds of Source (your camcorder) and the Sink (PC with cache RAM), and the bits in between. The speed of the OS may an issue. So, few suggestions.

1. Running XP suggests an old computer - the CPU may be fast but it probably isn't a dual (or more) core item. Look up the control panel system, or the windows system information pages, to check that. Dual cores really speed things up as long as the OS can handle it. Win 7 can. So, if you haven't changed the motherboard (!! I know, ripple effects and you need to check them out before committing, but speed is the thing now) think about doing this for one which supports a 64-bit CPU and RAM. Probably a new PC. That enables you to install the 64-bit version of win7 (the upgrade and new OS disks for it have both versions in the pack). Without doing anything else this will speed up your RAM, memory accesses (because each one gets double the information that an x86 processor can) and thus processing the incoming signal is much improved as a result of doing other necessary things.

2. using an external hard drive - make sure it's at least a USB3 device. And plug it into a USB3 interface in the PC. The speed usb 3 offers only happens when both ends (the memory and the PC) can perform the same dance. Depending on the motherboard: if there are non normally available on the rear panel (an old machine that originally ran XP probably doesn't have them) then that interface needs the PCI express interface - just PCI is just too slow.

3. Every disk drive has delays as result of moving the heads (seek delay) to find the information requested. Poofteenths of a second each time, but a program uses literally thousands and thousands of them (get the next program segment, get some data that program wants and store it, call the OS for function, store result somewhere else, repeat etc etc) and they mount up to significantly delay completion of a task. Especially if everything - the OS, program and data store - are all on the same hard drive, which is typical of a laptop. On a desktop or a laptop try and ensure that at least the data and the software are on physically different drives to minimise that seek delay effect. Create a pipeline effect whereby the information needed (data on one drive and program on the other) is already under the read heads of the device concerned. No seek delay on either one. Make sure any effort here is not cancelled by a slow connection - see comment 2.

4. The capture interface of VS has been critiqued for sometime as not being terribly good, so find alternatives. For example, use a dedicated version of the capture program. When I had a tape camcorder, the vendor (Panasonic in my case) supplied a PC program to capture the data being played to it. A firewire connection was an absolute must for that. Once the video files were on-board, manipulation with VS is easy. On a modern camcorder with removable memory cards (SD, xD etc) just swap the card between the camcorder and the PC.

5. Lastly, altho it's not much help with imagery already captured on a tape, get a new camcorder that records on digital media like SD cards. The DV tape camcorder I had - still have actually, in the bottom drawer - decided one day in the middle of a holiday in the Kimberleys, no help anywhere within 2000Km, to wrap the tape around its internal gizzards. The tape cassette could not be removed and the tech said later it was too expensive to even try. Holiday data gone. That happened some years ago now. When I bought a new one, I made sure that device had a memory which was easy to extract if the camera ever failed (SD cards) - that way, at least the captured images could at least be retrieved for processing. Cameras with internal hard drives have the same constraints as tapes - drive failure means images lost.

6. Check the size of your windows paging file (the virtual memory the OS uses to cache current process information on the C hard drive). Too small, and there's a lot more disk activity than there needs to be. It should be about 1.5 times the size of the installed RAM.

Davidk

[BrianCee]

your words in the first post in this topic are that you changed your operating system from XP to Win 7 - is that without making any changes at all to the hardware in your computer - is it still the same CPU as before ?

Stuttering problems capturing HD video are much more likely to be hardware related than software - did you upgrade any hardware apart from the external drive ?

[basa10]

Thanks to all for answering my post and sorry Ken I continued the first thread but had no answers.
I was told on the first thread that all my hardware was fine to both capture and upgrade to windows 7. The new H/Drive is 2 TB
internal and is connected with a SATA cable, it isnt partitioned. The windows is the 64 bit version. Both cameras are semi- pro ones,
Sony FX1 AND Sony HC1. I have been using HDV Split to check how many frames I have been losing and it can vary between one in an hour and up to 4.
The memory in computer is still at 4GB , I know I can double that. Im told that the mother board is at least 2 core and maybe a quad-core.
Thanks again and any more ideas would be welcome.

[Ken Berry]

And again I can only say I can't think why this is happening to you. You certainly don't require a Ferrari computer to capture HDV via Firewire without losing frames. I used to do it on a Pentium 4 with HDVSplit and had no troubles. These days I use either a Quad 6600 or an i3, which are my only computers with Firewire. But again I never have problems.

Mind you, I wouldn't personally classify 1 - 4 lost frames per hour as a huge problem... Have you tried recapturing sections of the tape where the drop-outs occur? Annoying, I know, but if you are really concerned that the missing frames are essential to a project, that is at least a potential work-around...

I assume using the non-split by scene capture of VS itself also results in dropped frames on the new system?

[basa10]

Hi Ken
thanks for your reply. I can use HDV SPLIT and let it stop capture and then rewind slightly and go from there.
I film motorsport (short circuit) and the tape camera is the main camera (with commentry, etc) and then I can have 3 or 4 other cameras in synk with the
master so if I dont check every piece of download it can all go 'pear shaped'. Because I film so much I dont really want to watch every second of download and then again when Im editing.
Thanks for your time and help. Barry

[Davidk]

Internal HDD using a sata3 device (faster than usb3: 3Gbps versus 450Mbps) with win64 covers most of the bases. Confirm the number of cores and check the size of the windows paging file. But given all of that looks Ok, I'd start looking at the tape camcorder as the source of your dropped frames. Bear in mind that the tape medium is essentially a mechanical device, both in transport (moving the tape for record and playback) and the tape itself (subject to stretch or loose wrapping in the cassette with a lot of use, and it would not take much to do this) - features not necessary with card stored imagery - so dropped frames in a system where everything else seems fast enough and is electronic are most likely to be at the weakest link - the tape recorder.

If you can detect the occasionally dropped frames, how? Are they at the start or stop of a recording sequence, and possibly affected by the startup and stop distances on the tape? Are they provably on the tape and not in the saved image on the PC? Or is this more of a case of I saw that event, and there are missing images from the recording I am watching?

At this point I would be inclined to try a substitute camera that doesn't store a recording on a mechanical device, ie a fully electronic one using memory cards (even an HDD camcorder has a mechanical storage unit) and repeat the record/transfer test, and establish if it still has dropped frames in the computer file.

Davidk