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  1. Far too goddamn old now EddyH's Avatar
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    Jan 2003
    Soul sucking suburbia! But a different part since I last logged on.
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    Edit: TLDR version - have a 20ish minute historic documentary, one of three on the same tape, its friends converted just fine from (cinefilm to) VHS to DVD in a consumer tape/disc recorder deck but this one has a field offset and/or display order error causing jerky movement - on what should be progressive material! - and obvious combing even on still scenes. Given my increasingly severe allergy to having to mess around inside the guts of DVD-format video when it's not absolutely necessary, and increasingly obsolete workstation PC, some way of applying software to the ripped-to-HDD VOBs/IFOs would be strongly preferred as I can probably muddle my way through demuxing then doing whatever processing and reconstruction/reauthoring is needed. Have spent better part of a week trying to find an answer independently and have got nowhere, between ancient threads, dead links, and software that *almost but doesn't quite* do the necessaries...


    Greetings fellows! It's been a while. I've not had much time for derping with digital video aside from recording things on Humax PVRs, capturing with good-enough USB DVBT and analogue devices and some set-top DVD recorder stuff of late (well there was the multi-angle Avisynth one-man edit mission fiasco of 2013, but we don't talk about that), and that which I have done was achieved either with simple Joe Consumer grade programs (they're so much better these days!) or Google, so I admit I've been vewy vewy qwiet. But now I am forced to throw myself on the mercy of your knowledge...

    Part of my current job involves the forward transfer of old VHS content onto DVD and/or into MP4 files for whoever rocks up and presents it (usually tutors, as I am at a university), so long as it's at least arguably quasi-legal to do so (ie we can argue fair use format shifting if it's not possible to just get a suitable PAL R2 version from Amazon for a pittance, or stream it using one of the various educational video archive sites). It's a task inherited from a much older guy who pretty much just sat on a bench dozing whilst the land was bought and institution built around him, then woke up to find he was sat in an office with people demanding all kinds of analogue photo/audio/video services from him, and in the couple years immediately pre-retirement busied himself cack-handedly copying huge stacks of old ERA-compliant tapes to low grade DVDRs using LP mode and not quite writing down all of the relevant information in a form anyone else could interpret... ahem.

    Thing is, trying to do it better than that whilst also carrying out other duties is heavily reliant on more automated systems doing what they're supposed to, and that's had a hiccup here.

    Got a tape handed to me by the library, a compilation of British 1940s newsreel-type documentaries focussed around on-the-scene panoramas and soundscapes during the later war years, and a slice-of-life docu-diary thing covering the terminal stages of WW2 and the immediate postwar period. Believe they're probably all public domain now, unless the act of transferring them to VHS about 25 years ago extended the copyright somehow (whoever was responsible for that did a very basic job, simply telecine-ing the original celluloid without the greatest overscan, and providing it with a very plain label and box inlay, so there's not much original IP inherent in that), and I haven't yet found a DVD version.

    It initially looked like that and a few other recent submissions were going to have to go via my established but not particularly efficient VHS to DVD workflow involving a couple different decks, some occasionally iffy cables, rather variable signal levels, a poor choice of quality modes and being careful with pushing multiple buttons on different, increasingly worn-out machines at once, but then a Samsung combined VHS/DVDR deck came available thanks to another department having a clearout. Quite good picture quality, sync-start, and even better a choice of speeds graduated in half hours from 1 thru to 3 hour on single-layer, though the original remote was gone.

    Have transferred a few things with it so far and they've come out reasonably well, apart from sometimes low audio volumes and inability to quite get the tracking entirely clear at both top and bottom (both probably down to the extreme age of some of the tapes, some of them are more than 30 years old and the non-commercial ones were recorded off analogue TV using a 1980s deck of probably very dubious quality) and an annoying ~13 line high area at the bottom of the 576 where the (not entirely brilliant, but serviceable) line-based TBC gives up the ghost and everything goes really squiggly (definitely inherent to the machine as it happens the same with every cassette). But the discs look alright when played back as normal DVDs on both TV and computer, and with suitable cropping (usually to about 680x560) and aspect ratio setting, high-grade deinterlacing to 50p, audio gain boosting and other careful encoding tactics in Handbrake the results come out entirely acceptable for the intended uses. IE we're just preserving investment in study materials, some of which are genuinely unique and irreplaceable, rather than making anything for showing off in a museum or broadcasting.

    The problem has come with this one tape. As there is a precious couple seconds of silent, black dead space between each of the three programmes, and the -R discs I'm currently having to use (as it's a single standard deck, and even if I *had* any -RWs, they're a really awful format compared to either -R or +R/+RW so I'd be loath to use them) doesn't allow any kind of editing other than renaming and deleting, I hovered over the stop button and then made careful with the rewind and pause to put each one on a separate track, which may or may not be the source of the trouble. Yes, I could have just recorded it all in one go and cut it up and reauthored on the computer afterwards, but, seriously, I'm not a student or gainfully unemployed any more. Life's too bloody short, and I've had about all I can take of havinging to be mess around ripping, demuxing, converting, chopping, transcoding, re-syncing, remuxing, menu preparing, authoring, burning.... etc... if there's no need to. ESPECIALLY if it involves DVD format material, which as far as I'm concerned is something that wasn't so much conceived by a panel of so-called industry experts, as mined from a particularly fragrant part of Satan's lower intestine; I've lost track of the man-days lost to making a really nice looking menu set for a carefully arranged set of optimally encoded files only for half of the stuff to either not work at all, or look/sound completely janked once burned and played. If the set-top hardware can do it in a satisfactory manner, and the people who are going to play it think it looks and navigates OK, and it doesn't require any additional hours of thumb twiddling and hoping nothing idiotic happens along the way because of a foible of the format or software, that'll do just fine.

    Anyway, the first two programmes on it are A-OK, there's some speckling and the like which I may enquire about removal techniques for at a later date (as, of all things, VLC's "Yadif X2" deinterlace filter shows signs of being able to remove them - if you play back at 25% speed with it turned on, they appear with the first field of each film frame then vanish once the second comes in, meaning even when played at 100% it has a less corrupted appearance than with the other, 25fps-only filters), but considering that the original films were themselves showing the effects of ~45 years of imperfect storage at the time of transfer, and they'd have shown up if the tape was still in use anyway, it's not a significant problem. It's patina

    The third programme, however - annoyingly the one where the pictures are more important! - has a clear interlacing error. It seems superficially OK on the 14" portable CRT TV I use as a disposable good-enough monitor for the recording and titling process, but when played back on any computer it has not only the classic leapfrog style herky-jerky motion (which is especially weird on footage that, as far as I can tell, was telecined with the film running at a rock solid 25.00fps and so should be effectively progressive), but also obvious combing along diagonal edges, even on stationary images, suggesting that the fields have at the very least been recorded in the wrong "positions", ie top is bottom and vice versa, and are maybe displaying in the wrong order as well (either a separate fault, or a side effect of the first). I somewhat doubt Handbrake's deinterlacer will make a good fist of that... and I don't know if, should I try to crop a line off the top and only trim 15 from the bottom instead of 16, it would apply that *before* any other processing (so possibly fixing the inverted positioning), or *after* (making everything even worse).

    The first thing I want to try here* is directly twiddling the flag bits in the relevant parts of the DVD filestructure and/or the actual MPEG2 video stream itself, if at all possible. As it's hopefully purely a matter of the original video signal having become displaced by 1/50th of a second relative to the DVD encoder vs the other two thanks to the stop-start recording process, this may be enough to fix it...

    *before going down the more well worn but ball-achingly tedious road of pulling the VOBs apart with DGIndex, loading it into Avisynth (and VDub) with DGDecode, using its powerful yet fairly easy to comprehend field-twiddling and motion compensating deinterlacers, then encoding straight to MPG4 from there using VDub (and extracting the stream/inserting a crunched version of the audio with AVIDemux) and re-encoding from the same source to MPG2 with HCEnc, muxing it back together with the audio and either seeing if said VOB can be shunted straight back into the on-disc version of the DVD or authoring a whole new disc with extracted streams from the other two progs and the least unreliable software I can find, then burning with fingers crossed very hard... The inherent water-torture of which is only made worse by the fact of doing it on what is now a very old workplace all-in-one PC with a 2.1ghz Mobile Core 2 Duo processor and fairly limited HDD space (and less of it contiguous) for multiple, "high" speed runs spitting out all the different alternative versions for cross-comparison. This thing is s-l-o-w when it comes to encoding video, and not even that quick when splitting or muxing...

    Problem is, I have so far found NO WAY of actually doing this. There's Restream, but it only works on extracted (and demuxed?) MPEG files rather than VOBs, as far as I can tell. IFOEdit doesn't seem to expose the flag anywhere, at least not in any obvious way. And any other otherwise promising tool or method yet seen have one, other, or both of those two problems, plus some additional stumbling blocks of their own.

    I mean ... come on ... surely there must be a way? It's a simple bit of control data that lets the player know how interlaced content should be output to the screen. One would hope that not only would its location either be known ahead of time, or at least easy to determine from the information in the IFOs and VOBs, but also that, as a one-bit switch (maybe 2~3 bits at most?) rather than some variable length string, it could actually be altered without affecting the rest of the file's structure or playability, or even needing very many sectors to be rewritten. But so far, across the whole internet, with some days of bouncing around both in google and yahoo/bing, scouring forums and program manuals and standards publications etc... nothing. Help!

    (fwiw, there were some potential links over to Doom9, both on the search engines and from certain places here, but their forum appears to either be broken right now (when it was up a few days ago, when I glanced at it and made a mental note to go back and check it out), or silently blocked by our local or's regional firewall. Either way, any address just times out after a couple thousand milliseconds...)

    Apologies for the screed, but if nothing else it'll hopefully nix all the "...have you tried/considered XXXXX?" suggestions which I'd otherwise spend three pages saying "yep, didn't work" or "nope, but I'm not going to unless I really have to" in response to.

    I mean, I probably could have done the demux-avisynth-remux/reencode thing by now, but a) I don't want to admit defeat, b) I'd rather come out of this with a quick and easy method I can use in future should I encounter a similar problem. Either however is better than being That Guy, you know, thhe one that looks after the conversions from DVcam to digibeta for the BBC News and seems to get it glaringly, unwatchably wrong 95% of the time... (and their colleague over at Midlands Weather who simply doesn't understand neither overscan nor aspect ratio...)

    Thanks muchly...

    (PS, side question: even the "OK" videos, of all kinds, seem to have some very minor combing under similar circumstances, kind of like the even lines are horizontally displaced from the odd ones by about one, maybe even one-half a D1 pixel; this I presume is down to an imperfect or at least not fully field/frame aligning TBC in the deck, and wouldn't really be noticeable when played on a TV (especially something with only about 400-500 horizontal pixels like that portable), but I CAN see it on the computer screen, and it's just annoying enough for me to want to see about fixing it. I know it'll require re-encoding, but is there any particular tool that'll sort it with minimal human interference? Or would it be a case of split fields, shift one of them sideways by a certain amount (1.0 or 0.5 pixels, maybe involving a horizontal size double first then shrinking back after), and recombine before encoding again? I might have to see if the same thing persists with running the old standalone VCR to the standalone DVDR, and thus whether it may still be preferable to use that setup for 0 to 60, or 91 to 120 minute recordings, even though the combi would still probably be preferred for 60-90, 120-150 and 150-180 minute...)
    -= She sez there's ants in the carpet, dirty little monsters! =-
    Back after a long time away, mainly because I now need to start making up vidcapped DVDRs for work and I haven't a clue where to start any more!
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  2. Post a sample. But it sounds like the top field is stored below the bottom field, and hence the field order is reversed at playback (in addition to the fields being spacially displaced). That's easily fixed with SwapFields() in AviSynth, or the Field Swap filter in VirtualDub. Of course, you'll have to reencode.

    Crop of a normal progressive frame on left, field swapped on right:

    [Attachment 40988 - Click to enlarge]
    Last edited by jagabo; 20th Mar 2017 at 11:18.
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  3. I actually did try to read through your entire post. It is extraordinarily long, but contains precious little information.

    I think you are trying to transfer a 1940s documentary; and I think you believe you have some sort of interlacing or combing problem; and I think you can't deal with it because you are capturing using a VHS to DVD recorder and for some reason don't want to use DGIndex and other tools to let you get at the MPEG-2 video and edit it.

    If I have surmised any of this correctly -- and I many not have because you introduced so many tangents -- then the solution is obvious, although it may not be what you want to hear: you need to capture the video to an editable format because, as you have noted, the VOB structure on a DVD is not a very friendly format to edit. Then, you need to post 10-15 seconds of this video (preferably a section containing lots of motion), without re-encoding, so that we can actually see what you are dealing with. Reading between the lines in your post, I assume you live in Europe and I assume this is PAL content. The documentary was obviously shot on film (no video in 1940). As you well know, that is usually just transferred from 24p directly to 25 fps interlaced by speeding it up slightly. In the old days, they wouldn't bother to correct the pitch. Thus, the usual way to restore this is to change the fps header in the captured file from 25 to 24, the pitch will take care of itself, and your work is done. Most modern equipment will play native 24 fps just fine, whether that equipment is NTSC or PAL.

    However, there are a thousand ways this video could have gotten screw up, and this includes format conversion to NTSC, and then back again. There are so many different things that can happen that, without a sample, it will be impossible to offer specific advice. The usual AVISynth tools are TIVTC (TFM/TDecimate), SRestore, along with custom scripts, depending on what other stuff is going on.
    Last edited by johnmeyer; 20th Mar 2017 at 11:24. Reason: added "lots of motion"
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  4. Far too goddamn old now EddyH's Avatar
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    Yeah, sorry, brevity isn't a strong suit (internal ADHD or something, idk), and I didn't know how long it would be before I could come back to answer questions, so I tried to include anything that might answer potential confusions. I have some time pressure on me to leave this building in the next few minutes, however, so hopefully I can be a bit more terse

    So, attacking things in order:
    Jagabo - yes, I'm fairly certain what the problem is, unfortunately, it's trying to fix it that's doing my head in. The effect is exactly as you've illustrated. The interlacing has gone back-to-front (I *still* haven't had chance to play the tape on another machine and see if it's intrinsic, or just something to do with the DVD transfer), so the lines that you'd expect to come in from successive fields as 1 - 2 - 3 - 4 - 5 - 6 - 7.... are instead 2 - 1 - 4 - 3 - 6 - 5 - 8... It's well hidden in flat, homogenous, or disruptively patterned areas, but extremely obvious with any diagonal edges or other detail that relies heavily on the vertical dimension. Including the title text...

    Playing it in VLC with the built in deinterlacing function also shows some slight motion judder with the high-motion algorithms, as it flickers between adjacent should-be-25fps-progressive frames, but that's missing with the standard-motion ones. The field-weaved staircasing effects remain in both cases.
    (thing is, if only the VLC coders would actually respond to the often renewed and much commented bug report/feature request to implement field-swapping, it would probably be able to export it straight from there into an MP4, which is what I'm most bothered about really... and moreover then take advantage of the particular effect observed with the high-motion deinterlacer on the two *correctly* recorded sections where the second 50fps frame generated from each 25fps original retains the full vertical resolution but has undergone a neat automatic despeckle/noise reduction filter that's removed all the tiny scratches)

    As I probably said somewhere in that novella, I know I could just rip it, feed it through AviSynth and re-encode, but I'm both dog sick of messing with things that way at the moment (successive RL problems have me quite worn down and I really can't be bothered with trying to Brain my way through it once again), and I'm feeling pretty bloody minded about it because, gods damn it all, there SHOULD be a non-destructive way of just flicking a bloody switch somewhere in the logic of the filesystem and the players and have the fields come out the other way up.

    I coulda sworn that interlaced MPEG2 stores the fields separately rather than mashing them together and then encoding the whole lot as one big potentially quite badly artefacted mess, so it's only a matter of putting Thing 1 into Box B and Thing 2 into Box A rather than the other way round... no processing needed. No futzing around with scripts and ripping and indexing and shunting the AVS into HCenc and muxing the audio back in and then trying to sneak the resulting mess back into the DVD filesystem so it'll play as if nothing had happened apart from the fix... etc. I mean, it sounds like a not too complicated thing at first, but when you break it down into the constitutent steps that are required to do that one small fix, the multiple gotchas of the baroque mess that is the DVD standard quickly start to make trouble and turn it into a longwinded and frustrating affair. When it may well be a single bit in a single byte somewhere.

    I mean, the files have a field order specified, because programs - like DGIndex! - are able to read and display it, so... where is it, in there? Where exactly are they reading it from, within the VOB? Some part of the program must run a routine that either goes to a known offset within the file, or scans through the header area looking for a particular byte sequence, then deciphers the data in that area to display that and other information. I'm not above using Debug or some other hex-level editor to dive in and change the one or two nibbles required to alter the code, if it's the brief scramble over a muddy hill that avoids a three-day trek around the base of it. Though if it turns out (as I fear...) that it's something encoded into every single frame, or at least every GOP, it could turn into a more tedious process that would either need some kind of little script written for it, or just abandoned entirely.

    (I may well end up doing at least part of the Avisynth method anyway, in order to make the MP4 version, but if it can be fixed for both branches of the archive tree with a single action, so then I just have to save the DVD filestructure for one part and point Handbrake at that folder to generate the other, well, why even bother?)

    Of course, the most likely thing, going by Murphy's Law, is that a Top Field is a Top Field, and a Bottom Field is a Bottom Field, and never the twain shall meet, and the only flag you can set is TFF or BFF, with no option of changing whether any given F is a T or a B...
    Last edited by EddyH; 4th May 2017 at 14:10.
    -= She sez there's ants in the carpet, dirty little monsters! =-
    Back after a long time away, mainly because I now need to start making up vidcapped DVDRs for work and I haven't a clue where to start any more!
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    The solution is simple, really: all you have to do is purchase the MPEG-2 and DVD specifications, read them, and write your own software program to remunchify the VOBs with the correct field order.

    Or you could run them through the appropriate Avisynth/VDub/FFmpeg filter, but that may be asking too much of the dog-sick.

    Perhaps the best course of action is to send your DVDs to me and I will straighten everything out for $80 per hour of labor.
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  6. I agree, way too many goddam words. We always say to provide all information about the problem but, as johnmeyer said, you go off on tangents only distantly related to the main problem.

    I'd try Restream on it first:

    1. Demux (PGCDemux)
    2. Take the resulting M2V and run it through Restream, changing the field order.
    3. If it works, reauthor (Muxman).
    4. Stick the fixed DVD back into the original (PGCEdit). You might not even need this step if all you have for menus are some really funky ones made by the DVD recorder.

    Or, as jagabo suggested, post a sample for us to play with. 10 seconds of a scene with steady movement will be plenty.
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  7. Far too goddamn old now EddyH's Avatar
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    Johnmeyer - ooh, I seem to have annoyed you ... my apologies. But thank you for taking the time to read through and try to decipher it all and help anyway!

    There's a lot of info in there I hope, but each particular piece is probably only relevant to someone who might have asked a certain simple follow-up question. If that question isn't on your mind, then, that data is irrelevant. Because of my limited logging-back-on abilities at the moment it was somewhat necessarily like dumping the whole call-response resource file of a text adventure game instead of playing through it interactively.

    But enough of the metastructure...

    * 1940s documentary: correct... one that I'm not sure of the existence on DVD, and it would possibly cost quite a lot to obtain on disc, but as far as I can tell we're legally clear for format-shifting. The people who asked me to copy it, after all, have been very firm about where the cutoff lies in terms of legal/not legal for our institution and it's caused problems in the other direction as a result.

    * Interlacing/combing problem: very correct. As confirmed above, it's like that posted by Jagabo. Except a bit fuzzer and scratchier and in black & white.

    * Yes, as I said in the previous reply, I am being deliberately obstinate about it specifically because the lack of any clear way to do it so far, even though it is almost certainly reliant on a tiny little flag inside the VOB (or a recurring series of them), has got right up my nose. Almost everything else about the disc and the video files can be twiddled using the usual tools, but for some reason this particular thing can't be.

    Also, I've had enough trouble up until now doing VHS -> DVD transfers with the tools available and thought that I might finally have alighted on a workable solution, and everything was going so nicely until the third section of this three-part presentation Total annoyance...
    ...and more to the point, without being able to easily determine, at least at this point in time, whether it's a problem with the original telecine, the VHS playing part of the deck, or the DVD recording part, it seems prudent to try and find a quick way to fix such faults in future that only affect the metadata, not the actual MPEG-encoded video, which otherwise looks just fine.
    (monochrome, not entirely pin-sharp material recorded in 1hr mode doesn't really stress even a realtime encoder very much)

    Because going through the DGIndex-Avisynth-Reencode-Remux-Reauthor motions for a single 20 minute clip once isn't too much of an issue. Having to do it for however many tapes might end up going the same way in future would be a much more serious undertaking.

    Carrying on...

    * When you say "editable format", I take it you mean... connect an analogue video capture device to the PC and do a live recording of the tape onto the hard drive as HuffyUV or Lagarith or even just raw YUV? Hooooo boy. That is really not a likely thing to happen. We haven't really got any such hardware that can be trusted to not make a complete scramble of the incoming signal, nor computers powerful enough. I've tried a few different options before, and have essentially given up on the idea.

    Let's just outline the background here. You can skip it if you want:

    One of my colleagues sometimes intercepts this kind of job when it's more urgent, and uses a rotten old bargain-bin player connected to his Macbook via some random USB thingy, and if it wasn't for the threat of disciplinary action I'd immediately eject the tape on seeing it happen, then put a hammer through both deck and dongle (...whilst I would be tempted to also attack the Mac, it is technically innocent). Because between the rotten state of the hardware and associated software (I'm pretty certain iMovie doesn't actually know what PAL is, but just pretends) and his own general ignorance about broadcast-standard video and tendency to just save whatever already questionably-captured material using the default export settings, the resulting file looks and sounds like absolute junk.

    But he gets away with it, and indeed has to be allowed to get away with it, because that method gets the job done in a fraction of the time of anything I could offer, between the sheer slog of the aforementioned PC-based workflow, and the unlikelihood of being able to get all the way through it uninterrupted. One of the reasons I haven't really been back much here in several years was that it just hasn't been practical for me to do much of serious productive use in the digital video field in my job, even though I should, and have had some stabs at it. The equipment, money, time and support just isn't there. I'm in education. It's a crapshoot right now. The computer I'm typing on is the same one I had back in 2010 when I last regularly hung out on VideoHelp and it was still called VCDHelp...

    Or at least, that was the case, until this combi VCR/DVDR deck became free during a clearout of another department, and seemed to be the answer. Direct transfer of 625-line interlaced source to 625-line interlaced sink, which could then be either used straight away, or ripped in byte-perfect fashion to hard drive and converted by a much more competent piece of software into an up-to-date file format. And when tested, it actually seemed to work decently well. There's a half pixel's worth of horizontal jitter on some older tapes, and the bottom 10 lines or so of every transfer get a bit mangled, but they're deep into overscan and can be safely cropped off anyway, with the side overscan borders (and a token amount off the top) producing a quite neat 4:3, 696x560 (anamorphic, from 5:4 encoded) final result. Joy. Much like the solution I almost had together with two different salvaged machines before but then fell apart due to dodgy cables and damaged sockets (-really- long story), and the impracticality of getting the two of them to sync in terms the disc stopping automatically when the tape signal dropped.

    So y'see things were kinda riding on that :/
    I know eggs, basket, etc, but I've not got many baskets to spare.
    -= She sez there's ants in the carpet, dirty little monsters! =-
    Back after a long time away, mainly because I now need to start making up vidcapped DVDRs for work and I haven't a clue where to start any more!
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  8. Far too goddamn old now EddyH's Avatar
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    Anyhow, it's not a complete bust. Whilst I'd much, MUCH prefer a solution that addresses the data I've already got...
    ...the last two, very much not-guaranteed-at-all analogue capture gasps remaining are:

    > the PCMCIA capture card that I have that plugs into my old, OLD laptop (I'm talking Cardbus, 2006, Windows XP, integrated parallel port, the works) and can seemingly just about sustain, when the moon is in the right constellation, maybe a half hour of continual recording at 720x576 25fps with high-bitrate and so low-CPU-load MPEG2. That outcome results of that setup because the card either doesn't have its own encoder, or at least the supplied software isn't smart enough to use one if it's there, and therefore it uses the laptop's own CPU to do the work. That kind of realtime encoding load pushes an ageing 1.73ghz Pentium-M right to the ragged edge of what it can do (in fact it generally auto-throttles to an average of 1.67ghz or so, in-between maximum and the next SpeedStep down, because even after deconstruction and cleaning out, the cooling system just isn't what it used to be... so going full-tilt makes it bounce off the thermal envelope... if I hadn't underclocked the voltage somewhat it'd be even worse), and technically it doesn't even meet the minimum spec, hence the input to the buffer is just a tiny bit less than the output, it g-r-a-d-u-a-l-l-y underflows, and eventually starts stuttering.

    I've used it before for capturing a shit-ton of stuff live off air when I had no other real option, but I knocked the horizontal resolution down in recognition of it mostly coming from channels which weren't full D1 anyway, so it was able to operate more comfortably at 1.60ghz without drama. That, I must point out, is not an option here, given that the horizontal resolution of monochrome PAL, even on VHS, is actually fairly close to what's encoded on DVD...

    Whether it actually records everything up to that point completely cleanly anyway, I can't be entirely certain, as none of its output has yet gone near a screen or software that I can use to determine that. It definitely doesn't seem to record in interlace, I know that much, and I have a sneaking suspicion it blends the fields. Like, not even just combing them together then encoding the frame as progressive. For the stuff I was using it to record during that stopgap period, it wasn't too much of a problem, but it's not viable as a first- or second-line solution.

    TL;DR it's not something I can really trust, certainly not without getting hold of a more powerful laptop that somehow still has a Cardbus port (the standard died out not very long after I bought it...) and some better software that can actually both recognise AND make use of the card. VirtualDub can't, I can tell you that much. Wasted several nights trying to cajole it into doing so, got nowhere fast. It did occasionally agree to record some stuff at 352x480 and 29.97fps (well, the FILE was 29.97, but the inefficiency of it going through VDub into a lossless codec then the machine's relatively slow HDD meant it only averaged about 14), but that isn't exactly something I'm interested in doing.

    Besides that, there's also...

    > the "AVid" USB2 based multi-port input and output box that I LITERALLY just found lurking in the workplace junk room YESTERDAY EVENING, much like the DVD recorder was. IF, and that's a humongous "if", I can get my newer laptop to talk to it, and drivers install, and it's actually compatible with Windows 7, and any kind of software is compatible with it, then there MIGHT be a chance. They are, I'm led to believe, a fairly major and prestigious video editing company.

    Unfortunately, this is not my first encounter with said box. It used to be installed in the same psychology observation suite as the combi deck. The idea was that the deck was only there for a while to transfer some old tapes that were taking up space on the shelves and didn't need to be archived for much longer anyway, and the capture box and computer would be used to live-record sessions in the interview room, with its twin PTZ camera and one-way-mirror setup.

    Well, after both myself and two different psychology technicians (one who is now HoD and has a fairly nice computer setup in their freshly built new wing on the other side of campus) had wasted quite a lot of time hacking away at the rig, plugging and unplugging, wiring things up several different ways, reading the online manual for the software back to front, searching around the net for just some kind of quick start primer on how to A) get some bloody video material into the virtual workstation via the capture box, B) make sound come along with it as well, C) perform any kind of editing action on it whatsoever, or indeed even get it to play reliably....... we just gave up.

    The very expensive, very high spec computer (which I also saw lurking in the same store room, but is the side of a fat sofa cushion and is ludicrously heavy, so I'm not sure whether to rescue it or just butcher it for parts) became the world's most extravagant Solitaire And Microsoft Word machine, and the DVD recorder took up permanent residence, perched on top of the old CRT security monitors that were also meant to be junked along with the tapes and original VCR (but were now needed to act as preview screens), and wired into the output of the PTZ control deck. And so it remained for several years until that room was finally decommissioned recently.

    So, to my knowledge, the box has never been used in anger, at least not in any kind of successful, productive way. Maybe in combo with my newer laptop and VDub it might suddenly come good. Or maybe it has actually just been broken all along.

    Anyhow, I REALLY have to exit now, so any further things I haven't got to will have to wait
    -= She sez there's ants in the carpet, dirty little monsters! =-
    Back after a long time away, mainly because I now need to start making up vidcapped DVDRs for work and I haven't a clue where to start any more!
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  9. Member bendixG15's Avatar
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    Originally Posted by EddyH View Post
    ...................................... Anyhow, I REALLY have to exit now, so any further things I haven't got to will have to wait
    don't rush........ we'll be here
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  10. By the way, this field swap problem is most common with MJPEG encoded video. It's easily fixed by using an MJPEG decoder with the field swap option.

    [Attachment 41495 - Click to enlarge]

    This is not the same thing as the "field order" you specify when encoding interlaced video. Interlaced field order is the temporal field order -- which of the two fields is seen first during playback. The field swap issue a spacial problem -- the location of the field on-screen at playback. Though the temporal problem often follows the spacial problem causing the judder you are seeing. For example, the video may be top field first and flagged that way, but the top field is stored as if it is the bottom field, so they play in the wrong order in addition to being in the wrong location.
    Last edited by jagabo; 4th May 2017 at 16:22.
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  11. You didn't annoy me at all. I was merely trying to express a desire, which as you saw from subsequent posts is shared by others, that you try to summarize in one or two sentences what problem(s) you are trying to fix.

    Also, the only way you can possibly get any help is by posting a 5-10 second clip which clearly illustrates the problems. If it is an interlacing or field reversal problem, that can usually be cured, either by changing your capture settings, or with very simple AVISynth scripts.
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