Still Massive Frame Drops *groan*

[Flying dutchman]

Check your motherboard bios setting if you have "HDD SMART ENABLED" . If so, switch it off. This option makes the computer do unnecessary communications with the HDD every few seconds. These "hickups" can be very annoying.

[Aryko]

I also found that disabling write-ahead caching made a big difference to the "hiccup" factor.

I do recall though that there was some issue about the fact that the NTSC (NSTC? I always mix it up) frame rate isn't exactly 30 fps, it's 29.997. So there was supposedly some incorrectly reported frame drops.

The main thing, IMO, is to do a capture and play it back; if it looks fine by the end of it (especially if it's a long capture), no loss of AV synchronization, then who gives a damn how many frames are reported dropped.

I never managed a capture without dropping frames. Actually, that's a lie, when I recorded without sound I never dropped a frame... Soundblaster Live, anyone?

But now that I've gone DV, I really don't worry about it much anymore.

- Aryko

[funsoul]

Hi Eric!

Just wanted to thank you and Flying Dutchman for the tips/comments/suggestions. All the permutations will keep me busy for some time am sure.

Jeeez...this is becoming a lot more than just an ordinary hobby *grin*
Thanks again

(damn...and am STILL dropping frames! wtf?!?! hehehe)

[Patrick]

Temporal cleaning is the process of removing "snow" type noise from video; a temporal cleaner looks at the small differences between several frames and smooths them out.

Eric, most of this thread has been well over my head, but this comment of yours has caught my interest.

1) Would this filter also eliminate "dropouts" which are a curse of the Hi8 format. Although I've recently acquired a digital camcorder, I've got dozens and dozens of analog Hi8 tapes that I'd like to edit with my RR-S. These "dropouts" range anywhere from a tiny blip on one line of video to a whole line getting screwed up. They only last for one frame, so I'm hoping that this filter could be of some benefit.

2) Does this filter only work with VirtualDub, or can it be used with other capture programs (such as MSP)?

Sorry if these questions are irrelevant, but as I've said, most of this thread has been well over my head. Thanks for any feedback.

[Patrick]

Walrus, I just clued into the fact that you developed this filter. Please feel free to also comment on my questions!

[Eric VanHeest]

I don't think the temporal cleaner is designed to handle intermittent full black frames; it is specifically written to function only in areas where the difference between pixels is low (you can configure it otherwise, but you lose the intended functionality at that point). I would recommend a separate filter that specifically removed large differences between pixels, instead of small ones, if I knew of one. A filter could probably fairly easily be written to effectively remove any drop to near-black followed by a return to almost the same color on a per-pixel basis, but I don't have any experience constructing them.

VirtualDub filters are for VirtualDub only, as far as I know. The format is completely open, but I doubt that commercial programs will use them. If you know how to write filters and plugins for MSP/Premiere/etc, and wanted to make a VirtualDub filter interpreter, that might be neat (it might also be slow).

[Walrus]

Temporal Cleaner won't help much if at all with dropouts (unless you get drop-outs with nearly totally black footage). As for developing a new filter to handle this... it can be done, though the possibility of severely ruining dark footage is very very high. The main problem with VirtualDub's filter architecture is that at best you can only keep track of previous frames, and thus you can only detect movements to black, not movements to and from black frames. If memory serves, there IS a way in VirtualDub to move between what it detects as scene changes (though it's escaping me at the moment). More importantly it's VERY easy to move between dropped frames to delete the neccesary frames. (Just look in the edit window)
As for filters moved to other platforms... when/if the filters become mature (ie: fast, and working), I may work on porting the filters to AviSynth and/or Media Studio Pro and/or Premiere. Anyways, the source code is released under the GPL for both so anyone who wants to work on rewriting the filters for any other platforms is free to as long as they keep it free and release the modified source code (and keep it all inside the GPL)

[Patrick]

Thanks for the responses Eric and Walrus, but there appears to be a misunderstanding with what these "dropouts" do. These dropouts do not, I repeat do NOT cause the entire frame to go black. The entire frame is fine except for a part of ONE line of video being affected. That's one line, not one frame. Does this now change what your answers would be, or am I still out of luck?

****************************************

After reading the post by funsoul which comes after this one, I felt I should mention again that these "dropouts" occur on the original Hi8 tape, and then are copied during video capture. This has nothing to do with frames being dropped during capture. Maybe this has something to do with the apparent earlier confusion.

[This message has been edited by Patrick (edited 22 September 2000).]

[funsoul]

Hi again

Well...for me...the dropped frames that are experienced when doing the raw capture show up as black frames when I'm editing the video.

The last number of captures (even a 70minute one last week)...I watch very closely and take notes as to the time that the frames drop. When I edit the clip...it's sped up the process as I know where to look for the drops but it still takes hours to go through and edit out every single black frame (that were reported as drops). With no editing...the balck frames are definitely visible on the movie.

H-E-L-P!!! There's GOT to be a better way! Am getting sustained throughput of almost 30meg/s.

-funsoul

[funsoul]

Woohoo!!! Well...found that with avi-io, if I select 'insert drops as full frames' that there are still tons of drops (approximately 1.8 per minute) but the dreaded black frame experience is no longer there!!! YAY!!!!

Also...after reading Dr Mordrid's message in another thread (where he recommends a 750-800MHz cpu for uncompressed), that would probably explain the drops to some extent.

Just wanted to let those of you who helped know that the issue is resolved (even though it'd still be nice to get 0 drops at least once *grin*).

Thanks again!
-funsoul