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Unofficial VirtualDub Support Forums > Off-Topic > Datavideo TBC-1000

Posted by: fccHandler Jun 10 2004, 07:47 PM

I am thinking of purchasing the http://www.datavideo-tek.com/navigation_frames/tbc-1000/entire.htm to help with capturing some poor videotape sources. Does anyone have one of these devices, and if so, what is your opinion?

Posted by: i4004 Jun 10 2004, 09:10 PM

isn't 100 somewhat cheaper? http://www.datavideo-tek.com/navigation_frames/tbc-100/entire.htm can't really comment on tbc directly,but i know i don't really need it... every so often i get a tape which obvioulsy bt8x8's sync separation circuit can't really understand(many 'field-drops'),but these are VERY rare ocassions... or are you more interested in overall image improvement which you think tbc may bring(less jiggly video)? ....i was very impressed by tbc inside jvc vcr(some clip arachnotron sent me) so tbc may be a good idea to cap vhs anyway... some folks will say better deal is to get DV camera that has tbc built-in...that way you pay some more,but get camera on top of tbc... personally,i would pick svhs machine with tbc(rather than tbc or dv camera),but more because of svhs' 5Mhz bandwidth than because of tbc itself(which i don't need as my panasonic vcr makes nice sync and 99% of the time bt8x8 loves it...) http://www.videohelp.com/forum/viewtopic.php?p=589097&highlight=datavideo+tbc100#589097 (notice the second post here;no sync means tbc won't help either...) http://www.videohelp.com/forum/viewtopic.php?p=667011&highlight=datavideo+tbc100 http://www.videohelp.com/forum/viewtopic.php?p=941532&highlight=datavideo+tbc100 because i don't have drops issue(most of the time) i would ask "The village idiot" to show me some before/after shots of datavideo tbc(or short clips),so i can see if it could calm-down the lines' left-right wiggle of normal vhs.. if it could,purchase would be justified.. but i don't have money for dv camera,svhs with tbc or datavideo... you can also see tbc as one more device in the chain(and it has it's own a/d+d/a converter...so it will introduce some signal deterioration...) hope that helped,and i hope you know what are you expecting from tbc...(if you're just dropping frames i would first try different vhs machine and different cap.card....both borrowed,offcourse... play safe..) edit;this should go to 'capture' section...not off-topic...

Posted by: fccHandler Jun 11 2004, 06:32 AM

Thank you my friend, those were excellent links. In simple terms, my problem with some tapes is that the video (even in preview mode) jumps vertically and/or seems to flicker. Dropped frames may occur, but I think they are merely symptoms of a deeper cause. My impression is that my capture card (ATI AIW 9600) is failing to sync properly with the vertical sync pulse. I thought it might be due to ATI's Macrovision detection circuitry kicking in. But I've run patches to disable Macrovision, plus I have a Sima Color Corrector box. This does help somewhat with the vertical sync, but it does nothing for the horizontal and I still end up with a lot of horizontal artifacts. It also introduces a bad "stipple" effect (from cheap ADC or DAC, who knows)... Curiously, I was able to get good captures of some tapes simply by using an older VCR. This suggests that the raw output signal is the culprit, rather than the ATI card.

Posted by: i4004 Jun 11 2004, 02:03 PM

yes,as i said,if your sync signals are too low or non-existant there is no guarantee that tbc will help either... this is because tbc uses sync signals as reference points(on where the line/field begins...those are the markation points on what enters the tbc's frame buffer...same as with any other video sampling a/d converter... ) so tbc is somethign that can improve the image stability(if tbc's adc's have lower threshold(than your card) to detect sync)...not something that can create sync signals from nothing... and yes,the source is important... (see the end of this discussionbetween me and scharfi http://neuron2.net/ipw-web/bulletin/bb/viewtopic.php?p=3508#3508t=429&highlight=weird+pattern his drops are a direct result of his 'grunding' vcr...) it also seems that different cap. cards have different thresholds for sync detection...so with same signal,some cards will drop and others won't.... another vcr may nudge up that signal few milivolts so it 'reaches' the ati....(as you saw) frankly,i'm surprised how good my panasonic vcr is doing....so far i only remember having issues with two(2) tapes that had 'field' drops which manifests as forth/back jerk...these were god knows which vhs generations...(probably 3rd or even 4th,other folks' stuff) offcourse this doesn't suggest that it would work for you...i can only say that pal model nv-hv60(and sd200 is still in working order,but it's mono.. ) works very nice with my bt878...that's for sure... you are also aware that these days cap.cards are cheap as dirt...you can get 4 tv-cards(or 8 capture cards) for the price of tbc that may or may not cure your vcr's signals...(although i think you can return any device(tbc OR cap.cards) if you're not satisfied with it..i mean that's america,right? ) the most infamous example along those lines(wasting money) are people that bought canopus advc100 only to find out that the poor bastard deals poorly with vhs...so they had to buy tbc on top of that! (in the end,that amount of money will buy a dv camera that does everything,and you get a camera..for free...) and in the end,"The village idiot"'s post suggests that there are STILL some tapes that tbc can't cure! well,my friend you payed too much money for a piece of crap...i'll give him that much... ... i'm wondering what QUOTE bad "stipple" effect is? can you post a screenshot,or a detail that ilustrates it? 'dots instead of lines'? cross-luma? on colored edges? there are 2 avs filters to deal with dancing-dots on ntsc(and one of those is ntsc only...)

Posted by: fccHandler Jun 12 2004, 04:38 AM

QUOTE (i4004 @ Jun 11 2004, 10:03 AM) i'm wondering what QUOTE bad "stipple" effect is? can you post a screenshot,or a detail that ilustrates it? It's most visible around bright red graphics, so I took two captures with my cable box display overlaid: For the first, I connected the VCR's composite cable into Sima Color Corrector, and captured the output from its S-Video feed. This shows the "stipple" effect: For the second, I captured the VCR's composite signal directly (no Sima Color Corrector): BTW, I discovered that a friend of mine owns a DV camera (presumably with built-in TBC), and I was so excited that he let me borrow it. I figured I could try passing my videotape signals through it. Unfortunately it only has a single set of A/V connectors, which double as inputs or outputs depending on whether you are in "record" or "play" mode. Drat!

Posted by: arachnotron Jun 12 2004, 10:39 AM

That stipple effect around the red edges looks like poor Y/C separation to me. (dot crawl) I own a similar home build 'sync enhancer' box as that sigma, (from an electronics magazine). It accepts both composite and svideo. From looking at the circuit diagram I found out that the main circuit operated on s-video only (separate Y and C) so when you fed composite into it, it would use a simple set of analogue bandpass filters to separate luma and chroma first instead of a proper adaptive comb filter. This would do horrible things to colored edges, making this box almost useless for composite sources. Capping s-video afterwards would not help any more, since the damage was already done. http://members.aol.com/ajaynejr/vidcomb.htm#Crawl and http://www.cybertheater.com/Tech_Reports/Comb_Filter_Tut/guide_comb_filters.html Gives some explanation of where these artefacts come from.

Posted by: i4004 Jun 12 2004, 01:30 PM

png? good lord,i'm on 56k,man! i also see anything in jpeg's just fine... stagecoach?my father loves that film... damn..isn't that jason robards on first pic... i agree with arachno:normal dot-crawl(accentuated by feeding the sima with composite..it can't really help with it's cheap separating circuit...as he said...) the sima made video look sharper,but this is that 'artificiailly sharper' sort of video (like 'peaking' the bt8x8 chip,or using unsharp mask or so..) however,i like sharpness in any form or way..(just ask arachno... ) for example i would have no troubles in makin bottom image look like top one with ffdshow etc. also,i can show you zillions of such images where my broadcaster 'wisely' used colored edges..they 'ring'(dot-crawl) for miles away..( ) luckily..i don't capture such tv-shows...but easy to see it.... as said,there are 2 filters to combat it one is guava-comb(by lindsey dubb,see doom9) and another is by 'verywetpaint'(see neuron2 forum) the latter is ntsc only... regarding your friend and DV camera:firewire anyone? it is cheap lil PC card...just stream that DV to your PC... perhaps it'll yield acceptable image quality too...(although i don't like DV that much...) anyway,analog output from that camera->ati huff capping would only produce analog view of DV,as that camera knows only of DV codec....you can never get uncompressed from it...(perhaps you could if you took it apart and take the video prior to entering dv-codec chip..heh) so it wouldn't make much sense to use it as tbc-only...it's more of an complete capping solution..(again,if the DV codec quality will satisfy you...) i myself had some color issues yesterday..anyone in the mood to port avery's chroma smoother to avs? real nice stuff!(as my picvideo mjpeg seems to be doing excellent take on chromaupsamplingerror) i should ask graft is he up for it...(or wilbert..or wilbert could ask shodan,or i could ask trevlac(aha..color is his stuff anyway!)) if anyone makes it,i'll make a new thread about that... edit;OUPS:that was mjpeg411 that looked crappy.... mjpeg422 looks OK.... an illustration inside this archive http://kotisivu.mtv3.fi/ii00i/mjpeg411/mjpeg-huff%20saturated%20red_.rar OUPS! sorry...

Posted by: fccHandler Jun 13 2004, 03:59 AM

@arachnotron: Thanks, your post explains it perfectly! QUOTE (i4004 @ Jun 12 2004, 09:30 AM) png? good lord,i'm on 56k,man! You were lucky; I almost posted the raw bitmaps, then changed my mind. QUOTE stagecoach?my father loves that film... damn..isn't that jason robards on first pic... Don't know. I've never actually seen this movie, but indeed I might check it out later because it looked pretty cool... QUOTE anyway,analog output from that camera->ati huff capping would only produce analog view of DV,as that camera knows only of DV codec....you can never get uncompressed from it...(perhaps you could if you took it apart and take the video prior to entering dv-codec chip..heh) Well, the point was simply to force its TBC to kick in, just so I could see if time base correction will really help my poor videos, before I blow $300 on a standalone TBC unit. I suppose I could purchase a DV tape to make an intermediate recording of the input from VHS, then capture (or dump) the DV output to PC. I would hope that the camera's TBC kicks in at some point during the process... In fact, I think I'll try that next. Thanks again to both of you for your replies!

Posted by: TCmullet Jun 29 2004, 03:03 PM

QUOTE (i4004 @ Jun 11 2004, 09:03 AM) not something that can create sync signals from nothing... What if it's a fullframe tbc? Those one to 3 line tbcs like in the Pan. AG-1970, are almost worthless for that reason, AND that they seem to add chroma noise for some unknown reason.

Posted by: fccHandler Jun 29 2004, 03:16 PM

I meant to follow-up on this thread. The TBC in my friend's camera works extremely well, and I was amazed by the beautiful and stable picture from my old VHS! Truly miraculous. I can only capture (or dump) the video in DV format, but it looks tons better than any other method I've tried to recover these poor tapes. Needless to say, I've been recording like a madman (since I must return the camera soon) so I haven't had time for much else lately, like forum-talk.

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