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  1. Originally Posted by lordsmurf View Post
    Originally Posted by ConsumerDV View Post
    It was so barely adequate that it created a whole new industry of digital shooters and DV rebels who started making real movies, while VHS became famous mostly for shooting porn and low-budget horror flicks.
    Nonsense.

    DV was "in" because of TINA (there is no alternative). Therefore DV was "best" (and only). But that was 25 years ago, the 1990s.
    What exactly is nonsense? That there were no serious movies shot in VHS, whereas DV gave rise to inexpensive filmmaking? Mike Figgis, Lars von Trier, Steven Soderbergh, David Lynch, Steve Buscemi shot on DV to name a few.

    Originally Posted by lordsmurf View Post
    I can't believe it's now the 2020s, and people still try to defend DV quality. It was already a has-been format by the early/mid 2000s. We've all moved on. Perhaps you should as well.
    In this case Hi8 and VHS are not just "has been", they are "had been". What are we doing here then, digging through forty-year old trash? Sony HXR-NX100 can shoot DV. There are other camcorders that can.

    Originally Posted by lordsmurf View Post
    VHS was a flawed format, but DV was just as flawed. And sadly, in some ways (color/chroma), flawed worse.
    Nope, it is not just as flawed. It is much, much better. It was a game changer. In fact, it is better than Betacam SP and almost as good as Digital Betacam. I bet that these links are well known here, I'll post them just in case.
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  2. Video Restorer lordsmurf's Avatar
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    Your obstinate intentional lack of understanding, combined with a desire to post links (several of which have nothing to do with the conversation), is making you seem silly.

    DVCAM and DVCPRO is another conversation entirely, non-consumer latter DV-derivative digital formats.

    The math of DV does indeed state it should be better than most analog videotapes. It is not. Practical application trumps theory at times. This is one of those times. One of my favorite quotes comes from the movie JFK: "Theoretical physics can also prove that an elephant can hang off a cliff with its tail tied to a daisy! But use your eyes, your common sense."

    There were movies/TV shot on analog videotapes, VHS/consumer and otherwise. There were also movies/TV shot on various crappy film stock. Later on, digital formats. But there's nothing special about digital formats, it can be good or crappy. DV is old, 1990s old, and by almost any 21st century (2000s-2020s) metric pretty crappy.

    I don't understand DV fanboys.

    DV is the format of the late 90s, into the early 00s, nothing more. And it has not held up well at all.

    If you want to shoot DV, convert to it, fine, whatever. But at least understand and acknowledge the limitations. Don't pretend it's the bestest format ever. It's not.
    Last edited by lordsmurf; 7th Apr 2022 at 18:34.
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  3. Originally Posted by lordsmurf View Post
    Your obstinate intentional lack of understanding, combined with a desire to post links (several of which have nothing to do with the conversation), is making you seem silly.
    Silly is someone claiming that DV "was barely adequate as a shooting format" and throwing hands in the air, "I don't understand DV fanboys," despite the well recognized role of DV in democratizing moviemaking and the mountain of movies shot on DV. Lollo, on another hand, helped me with a couple of useful links

    Originally Posted by lordsmurf View Post
    Videotape isn't any better than digital. ... And yes, some aspects better than some digital, but mostly worse.
    Ok, then
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  4. Video Restorer lordsmurf's Avatar
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    Originally Posted by ConsumerDV View Post
    DV in democratizing moviemaking
    Is was democratized (able to be used by the common man) decades before DV came into being.

    Overall, digital not better. Just different.
    However, aspects are clearly better, or worse. MiniDV, for example, has worse chroma/color performance, when used as a conversion format. For shooting, eh, still not great, but also not terrible.

    You just need to be able to recognize strengths and weaknesses, not be a fanboy about formats. Otherwise you'll never be able to successfully navigate those in projects, be it shooting or conversion.
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    Is was democratized (able to be used by the common man) decades before DV came into being.
    Have to disagree with that. Shooting video? Yes. Editing it and actually using it? No way (unless you used two VCRs to dub across). Even in the 2000s, unless you had a very expensive rocket-machine, you wouldn't dream of editing lossless video like we do now.
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  6. Capturing Memories dellsam34's Avatar
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    The DV format in its day was a great shooting format, Transferring those memories to computer is still the right choice, But using DV to capture other analog formats has only one purpose, convenience and hassle free assuming installing firewire drivers on newer OS's is still possible. Claiming to be the superior method of preserving analog tapes is just a reason for arguing.

    We've seen a lot of new members pop up here arguing their way in claiming to be Gods of video, most of them end up banned and vanished forever, Let's keep this place a learning place and stop posting for the sake of arguing please.
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  7. Member DB83's Avatar
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    Originally Posted by dellsam34 View Post
    .........

    We've seen a lot of new members pop up here arguing their way in claiming to be Gods of video, most of them end up banned and vanished forever, Let's keep this place a learning place and stop posting for the sake of arguing please.

    +1


    Way back in Reply #31 our new 'expert' claimed no knowledge of DV yet he now champions it. More than that let me dig up older threads and post more drivel.


    A desire just to post does not make you an expert. Trying to justify your comments does not earn more 'Brownie points'. In fact it takes takes threads off their original path. Help, yes. Hinder, no.
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  8. Captures & Restoration lollo's Avatar
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    The DV format in its day was a great shooting format
    I agree with dellsam34 and ConsumerDV: DV was an excellent format for shooting at its time at consumer level. A game changer. I have many important memories on > 250 miniDV tapes, digitally "copied" to my HDDs without any quality loss or issue.

    DV is not the best method to convert Analog formats to digital. A lossless 4:2:2 capture with right material is recommended.
    However it has some feature: easy of use, as noted by dellsam34, and I would also add "easier" audio/video synch.
    I remember the old times of capturing video with a PCI card and audio with a separate card at different internal clock jitter. The problem were solved with VirtualDub internal engine improvements (thanks again A. Lee for all your effort) and feeding a clean signal with line and frame TBC, but the DV route was much less prone to problems.
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  9. Member Skiller's Avatar
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    lollo sums up nicely what I think of DV as a capture format. It is not the highest quality option, but depending on a person's expectations, time, money and experience DV may in fact in some cases be the right choice, yes even in 2022.


    When it comes to DV as a shooting format, I feel the urge to say it was perfectly adequate. I shot DV mostly in the late 2000's. At that time, if you didn't want to spend on an HDV camcorder that nobody would get to watch in HD anyways – due to DVD still being the only feasible distribution format – DV was the best choice still. What were the alternatives?

    • DVD camcorders (record straight to a DVD blank – awful)
    • HDD camcorders (record in MPEG2 to a built-in hard drive, technically not bad but cumbersome)
    • early AVCHD camcorders with bad encoding implementation (mushy video) and, for the time, really high hardware requirements


    The choice for me was easy and in fact it wasn't until 2014 (!) that I stopped shooting DV.




    Originally Posted by dellsam34 View Post
    I still don't think there is a difference between NTSC DV and PAL DV in terms of chroma, I think both butcher it.
    If you want to put it that way – chroma is butchered in any consumer format because it is always cut down to 25% of the luma resolution.

    I mean you can't say PAL DV chroma sucks but mp4 AVC chroma is fine.
    The problem with NTSC DV chroma is the uneven distribution of chroma detail. It's severly smeared on the horizontal axis. The fact that the vertical axis is super sharp doesn't help aid this. Most people here think this is far more objectionable than the even chroma sample points distribution of regular 4:2:0 formats such as PAL DV, DVD, etc. even though the total amount of chroma sample points is the same.
    Last edited by Skiller; 8th Apr 2022 at 14:01. Reason: typo
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  10. Captures & Restoration lollo's Avatar
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    The problem with NTSC DV chroma is the uneven distribution of chroma detail. It's severly smeared on the horizontal axis.
    Yes. The following pictures, taken from https://www.mir.com/DMG/chroma.html, explains what happens: the higher vertical sampling does not avoid the damages of the low horizontal sampling. PAL is more "homogeneous":

    4:2:0 DV-PAL (SMPTE)
    Image
    [Attachment 64183 - Click to enlarge]



    4:1:1 DV-NTSC
    Image
    [Attachment 64187 - Click to enlarge]
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  11. Originally Posted by lollo View Post
    DV is not the best method to convert Analog formats to digital. A lossless 4:2:2 capture with right material is recommended.
    However it has some feature: easy of use, as noted by dellsam34, and I would also add "easier" audio/video synch.
    Well, this kinda was my point when I said, "DV is a well-supported format with known frame geometry and correct header info coming from a camcorder. When capturing as analog there are more variables." I still think the same. "Old experts" on this forum surely prefer going analog uncompressed route, but for someone who just wants to digitize their 8-mm video, using built-in A/D converter is a simple and reliable way to get a decent result. Even better, one does not need to think twice whether the recording is analog or digital - the original question of this thread - the camcorder will take care of it.

    I have never suggested that converting to DV is the best option. In fact, I found this guy's videos long before I joined this forum. I wonder is he a member here? His most viewed video is about a 1992 San Francisco trip, shot with a Sony CCD V6000 Hi8 Pro. He captured it through SVideo into AJA KONA LHi, edited in Davinci Resolve as interlaced, then deinterlaced with QTGMC and upscaled. He has a video where he showcases his workflow. This is not something a casual Hi8 user would do.

    Originally Posted by Skiller View Post
    If you want to put it that way – chroma is butchered in any consumer format because it is always cut down to 25% of the luma resolution.
    Ah, this is what "butchered chroma" means! 180 chroma samples across a scanline is butchered chroma, but 40-something chroma samples is not, I guess. Now thinking about it, it is not just how many chroma samples are there, but the color averaging, which in case of "quarter chroma" can cause significant shifts indeed. Obviously, color in 4:2:2 subsampling is closer to truth. Thank you for reminding me of that.
    Originally Posted by Skiller View Post
    The problem with NTSC DV chroma is the uneven distribution of chroma detail. It's severly smeared on the horizontal axis. The fact that the vertical axis is super sharp doesn't help aid this. Most people here think this is far more objectionable than the even chroma sample points distribution of regular 4:2:0 formats such as PAL DV, DVD, etc. even though the total amount of chroma sample points is the same.
    AFAIK, one of the reasons for different subsampling formats was that NTSC was very low res format - I could see scanlines on my 27-inch CRT TV - so it is not exactly super sharp vertically unless you squish these lines together. 50 Hz formats have 20% higher vertical resolution, so skipping chroma on every other line does not hurt it much, but then you get denser distribution horizontally.

    Considering that analog video has chroma encoded in every line but with very low resolution, I think that 4:1:1 fits it better than 4:2:0. Obviously, 4:2:2 is better than both, and I have not even tried to argue with that.
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  12. Captures & Restoration lollo's Avatar
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    Considering that analog video has chroma encoded in every line but with very low resolution, I think that 4:1:1 fits it better than 4:2:0
    It's the opposite
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  13. Member Skiller's Avatar
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    Originally Posted by lollo View Post
    It's the opposite
    Depends on whether we are talking about analog PAL or NTSC. Let me elaborate.


    Originally Posted by ConsumerDV View Post
    Considering that analog video has chroma encoded in every line but with very low resolution, I think that 4:1:1 fits it better than 4:2:0.
    You are right, 4:1:1 does fit analog NTSC better than 4:2:0.
    PAL on the other hand does what the name suggests (Phase Alternating Line) and averages chroma with every other line in order to automatically eliminate tint errors when broadcast over the air (this is also the reason PAL TV sets never had a tint control). Hence, in analog PAL there is only half the chroma resolution vertically and so 4:2:0 fits well.


    Let's investigate further into analog NTSC chroma.
    Analog NTSC uses YIQ color modulation. As usual, Y is luma; I is orange-blue axis and Q is purple-green axis. Unlike analog PAL, which uses YUV, YIQ allocates different bandwidths between the two color channels. For broadcast, I is limited to 1.3 MHz and Q to 0.4 MHz. So that would be about 177 columns of chroma(*).

    Those bandwidths can be higher for non-broadcast scenarios, especially in conjunction with S-Video.

    Actually, analog NTSC generated off a digital RGB source, such as for example a video game console, via S-Video, does look surprisingly good. The full vertical chroma res becomes evident. It's better than PAL in this case, which even over S-Video does lose chroma definition due to the inherent averaging. (Not taking the differences in line count into consideration here.)



    A major issue with 4:1:1 is that it is not supported in any common distribution format and needs to be resampled to 4:2:0 losing another 50% of the chroma resolution.



    (*) The math behind it is:
    (1.3 + 0.4) * 1000 * 1000 / 30 / 525 * 0.82 * 2 ≈ 177

    another way:

    (1.3 + 0.4) * 2 * 52 µs ≈ 177
    Last edited by Skiller; 8th Apr 2022 at 17:28.
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  14. @Skiller, thanks for the explanation! I appreciate the math too.
    Last edited by ConsumerDV; 8th Apr 2022 at 17:32.
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  15. Formerly 'vaporeon800' Brad's Avatar
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    Originally Posted by Skiller View Post
    You are right, 4:1:1 does fit analog NTSC better than 4:2:0.
    What analog NTSC consumer formats actually offer full vertical chroma resolution? There's LaserDisc, but anything else?

    I've tried to generate or locate an (S-)VHS tape with unique chroma on every scanline, and failed every time.

    Originally Posted by Skiller View Post
    A major issue with 4:1:1 is that it is not supported in any common distribution format and needs to be resampled to 4:2:0 losing another 50% of the chroma resolution.
    Technically, no version of DV chroma is supported by any modern distribution format, since it uses a unique sample siting structure.

    https://docs.microsoft.com/en-ca/windows/win32/api/dxva2api/ne-dxva2api-dxva2_videochr...m=MSDN#remarks

    https://forum.videohelp.com/threads/298618-PAL-DV-which-of-these-4-2-0-subsampling-rep...ion-is-correct
    https://forum.doom9.org/showthread.php?t=139023
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    Originally Posted by Brad View Post
    What analog NTSC consumer formats actually offer full vertical chroma resolution? There's LaserDisc, but anything else?
    Not really sure on this, but technically any analog NTSC consumer format should at least store full vertical chroma res, as no analog format by itself has any means of reducing vertical chroma bandwidth. The playback, or maybe already at recording, is where it most likely gets nuked.

    Originally Posted by Brad View Post
    I've tried to generate or locate an (S-)VHS tape with unique chroma on every scanline, and failed every time.
    "VHS HQ" circuit is supposed to average chroma lines in order to tone down chroma noise. So if it works at all with (S-)VHS (and similar) it has to be in EDIT mode.

    Have you tried recording, preferably via S-Video, to an S-VHS deck in EDIT mode and then playing it back on the same machine right after?

    Originally Posted by Brad View Post
    Technically, no version of DV chroma is supported by any modern distribution format, since it uses a unique sample siting structure.
    Indeed, but re-siting PAL DV chroma to common "MPEG2" sited 4:2:0 chroma is not particularly destructive. But it needs to be done.
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  17. Formerly 'vaporeon800' Brad's Avatar
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    Originally Posted by Skiller View Post
    Have you tried recording, preferably via S-Video, to an S-VHS deck in EDIT mode and then playing it back on the same machine right after?
    That's exactly the first thing I tried, lol. (There is no EDIT mode for recording; only playback. But I assume that's what you meant.) As I recall, enabling playback DNR&TBC seemed to tighten up the chroma resolution, but it still didn't look discrete per scanline.

    Maybe recording a test pattern to Hi8 would have a higher chance of success since there was no "HQ" circuit for 8mm tape formats?

    Originally Posted by Skiller View Post
    Indeed, but re-siting PAL DV chroma to common "MPEG2" sited 4:2:0 chroma is not particularly destructive. But it needs to be done.
    Any info on this process? I don't know anything about it since I'm NTSC-land.
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  18. Pretty much every VHS VCR will have a C comb filter on during normal playback which adds in some or all (not sure exactly) of the previous line (NTSC) or the signal 2 lines delayed (PAL) to reduce the impact of chroma crosstalk. The chroma signal on tape is "phase rotated" such that chroma picked up from the adjacent video tracks cancels itself out when ran through this filter. Betamax does this as well, but instead of rotathing phase, the chroma shifted up/down slightly in frequency on every track to achieve the same thing. Something similar is used on 8mm but don't remember the details there.

    VHS HQ specs additionally included an optional more fancy "recursive comb filter", which was mostly only applied in higher end or SVHS decks. Additionally, decks can have other forms of chroma noise reduction.

    EDIT setting should normally turn this off, in addition to most luma noise reduction and sharpening/detail enhancement, to avoid chroma shifting downwards on successive on dubs (It's quite noticeable on PAL since due to how PAL works a 2 line delayed signal is used) though I don't think there is any specific standard for how EDIT is supposed to behave. I don't know how EDIT mode on 8mm behaves in comparison.

    When quickly looking at some tests captures, it seemed as though my JVC HR-S8600 and XVS20 are compensating for chroma shift if not in EDIT (both have some digital chroma processing), while my Panasonic SVHS HS870 (despite the fact it has 3D DNR) and other normal VHS decks do not, but would have to check deeper to say for sure (with combinations of settings and capture device).

    On the Panasonic NV-F77 VHS you can see the chroma shift when it's not in EDIT mode (this has some extra CNR I think but not sure):
    Normal: Image
    [Attachment 64213 - Click to enlarge]

    Edit: Image
    [Attachment 64214 - Click to enlarge]


    The first picture is where chroma ended up on two other standard VHS decks too, while on my HR-S8600 it's lined up like on the edit one with edit and auto setting.

    Additionally a composite PAL decoder will of course normally average 2 and 2 chroma lines due to how it works, though you may get it with composite NTSC too to some extent, not sure.

    Would have to check the schematics to be sure, but even with EDIT active the vcr may do some filtering when recording though. Especially if recording from composite, but may also be the case when recording from S-Video and may vary depending on VCR.
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  19. Video Restorer lordsmurf's Avatar
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    Originally Posted by ConsumerDV View Post
    Well, this kinda was my point when I said, "DV is a well-supported format
    But DV hasn't been "well supported" for many years now.

    Trying to get Firewire to work properly is the first problem. It's the 2020s, trying to use a 90s-2000s communication method. It's like trying to use a parallel or comm port, on a modern system. It requires adding hardware, and drivers -- and good luck with that, too often problems. For example, you have to avoid certain expansion chipsets, and drivers versions. Fun! Same for the conversion dongles (ie, Thunderbolt>). This isn't a task for newbies, and it may not be an option at all unless you're using a standard desktop.

    Next comes the issue of software. The "best" is WinDV. Not bad, but it has so many drawbacks, especially in constant file breaking (even when told not to). You can instead try Scenalyzer, or an NLE (low-end or high-end). But again, good luck with that. Problems.

    Mac was always a DV centric workflow, almost no capture hardware/software options. It does tend to work decently on pre-M Macs. (For conversion, not shot DV, Mac is really the wrong tool for a capture task, and you sacrifice quality by doing so. With few exclusions, all using Intel Macs from 10.6.8 to 10.14 only.)

    USB is, and has been for over a decade now, the actual "well supported" comm method. There are some USB>Firewire options, but then you will run into OS issues. Win10 sucks, new M1 Macs not any better.
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  20. @lordsmurf, DV as a video recording format is very well supported across NLEs as well as on pro camcorders intended for reporters (I do not expect BMPC to record DV). It is supported by major operating systems. It is the lowest common denominator. Tapeless camcorders record DV on solid-state media and on PDs (if someone still uses them).

    DV can be 4:3 or 16:9, it can be progressive, it is versatile, and its processing is lightning fast, which is still important to some, somewhere. This is DV (YouTube video). M1 changed things, allowing editing 8K in real time, but not everyone has an M1 MBP yet.

    Firewire is just a nuisance to get DV off tape. FireWire riser cards are $15 on eBay. I have one in my current PC, it it two years old. Refurbished PCs that can be used for DV capturing and editing are $150. Don't like Win10? I am on the same page with you (or is it a boat? Or a bus?) Reinstall Win7. I am luckier than some, I have a distro legally downloaded from MSDN while I had this option. This is one of my most prized possessions.

    How come buying a DVD recorder to use it as a TBC is a thing, but buying a full-fledged computer for capturing and editing DV is not? Going on a tangent, I was about to buy a Toshiba D-KR2SU, which was praised by Sanlyn for its TBC qualities, but decided against it. I don't want to make capturing full-size VHS tapes my thing, I wanted to draw the line at capturing VHS-C and SVHS-C If someone wants this Toshiba, add it to your watch list, and maybe the seller will offer you an additional discount. $57 shipped is not very expensive, but I could not bear buying a box that is a full fledged DVD recorder only to use it as a glorified composite-to-SVideo converter.

    Then again, some camcorders can send DV via USB.
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  21. Video Restorer lordsmurf's Avatar
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    Originally Posted by ConsumerDV View Post
    across NLEs as well as on pro camcorders
    Hardware to connect cameras/bxoes isn't codecs.

    It is supported by major operating systems.
    It's a 1990s format. OS care less and less about these old tasks. Not even legacy tasks anymore, just old now.

    Tapeless camcorders record DV on solid-state media
    Great. My car only needs an oil change every 10k miles. Equally off-topic to Digital8, and the added conversion on DV methods to convert analog (Hi8, others).

    Reinstall Win7.
    It's getting harder to "convince" (aka, "talk sense into") people to use the OS of the era for the task of the era. However, again, DV is a 1990s tech, carried into early 00s. Why still use it? It's inferior for the purpose of convert or shooting. Even digital "capture" transferring DV has a problem with lost footage, which is why many still analog convert it. The loss is minimal for home camcorders, the optics, sensor, and codec/compress didn't really allow 720 anyway, just theory max.

    How come buying a DVD recorder to use it as a TBC is a thing,
    TBC(ish) passthrough on certain specific Panasonic items, strong+crippled unique TBC, non-TBC frame sync, some ugly side effects (but tolerable for a net effect of improvement, where no better is allowed).

    Going on a tangent, I was about to buy a Toshiba D-KR2SU, which was praised by Sanlyn for its TBC qualities, but decided against it. I don't want to make capturing full-size VHS tapes my thing, I wanted to draw the line at capturing VHS-C and SVHS-C
    I've never been impressed by Toshiba recorder, for any sort of TBC use. Only for recording quality off-air in the analog days (now gone).

    Then again, some camcorders can send DV via USB.
    I've never seen this.
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  22. Originally Posted by lordsmurf View Post
    Originally Posted by ConsumerDV View Post
    Tapeless camcorders record DV on solid-state media
    Great. My car only needs an oil change every 10k miles. Equally off-topic to Digital8, and the added conversion on DV methods to convert analog (Hi8, others).
    This was my response to "DV hasn't been "well supported" for many years now", which I believe is not true.
    Originally Posted by lordsmurf View Post
    Originally Posted by ConsumerDV View Post
    Then again, some camcorders can send DV via USB.
    I've never seen this.
    I started a thread here. BTW, it was discussed on this forum before. This 2015 thread seems to be the most specific of them, with actual users' reports.
    Last edited by ConsumerDV; 10th Apr 2022 at 19:55. Reason: Rephrased my response.
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    Originally Posted by Brad View Post
    Originally Posted by Skiller View Post
    Indeed, but re-siting PAL DV chroma to common "MPEG2" sited 4:2:0 chroma is not particularly destructive. But it needs to be done.
    Any info on this process? I don't know anything about it since I'm NTSC-land.
    It works by shifting the U and V plane vertically, each at individual amounts and also different for top/bottom fields.


    This script converts interlaced DV-sited YV12 chroma to interlaced MPEG2-sited.
    Code:
    separatefields()
    raw=last
    selectevery(2,0)
    Y = ConvertToY8()
    U = UToY8().Spline16Resize(width()/2, height()/2, src_top=-0.125)
    V = VToY8().Spline16Resize(width()/2, height()/2, src_top=0.375)
    even=YToUV(U, V, Y)
    raw
    selectevery(2,1)
    Y = ConvertToY8()
    U = UToY8().Spline16Resize(width()/2, height()/2, src_top=-0.375)
    V = VToY8().Spline16Resize(width()/2, height()/2, src_top=0.125)
    odd=YToUV(U, V, Y)
    interleave(even,odd)
    weave()


    Let's do an experiment to see how much damage this conversion introduces. I used this image which was professionally drawn by me in Paint.
    Seriously, the difference is basically invisible with an actual chroma zone plate, so this does the job.

    RGB 4:4:4
    Image
    [Attachment 64250 - Click to enlarge]





    First I converted to regular MPEG2-sited interlaced YV12 and back to RGB. All conversions are interlaced, as most stuff shot on DV is interlaced. Plus, it's also the worst case in terms of chroma. I'm using the conversion functions of Dither Tools by cretindesalpes because apparently the internal AviSynth functions get the DV siting wrong, unless this was fixed in newer AVS versions (no idea). It doesn't make a difference for this image, as there is no DV siting involved yet.
    Code:
    ImageSource("ChromaTest_RGB.png")
    
    dither_convert_rgb_to_yuv(interlaced=true, cplace="MPEG2", chromak="Spline16", mode=-1)
    dither_convert_yuv_to_rgb(interlaced=true, cplace="MPEG2", chromak="Spline16", mode=-1)
    RGB to YV12 to RGB
    Image
    [Attachment 64251 - Click to enlarge]





    And finally I converted the RGB source again, but this time to DV-sited YV12 and use the above script to convert it to MPEG2-sited (as we would need to when converting PAL DV to basically anything else).
    Code:
    ImageSource("ChromaTest_RGB.png")
    
    dither_convert_rgb_to_yuv(interlaced=true, cplace="DV", chromak="Spline16", mode=-1)
    
    
    
    separatefields()
    raw=last
    selectevery(2,0)
    Y = ConvertToY8()
    U = UToY8().Spline16Resize(width()/2, height()/2, src_top=-0.125)
    V = VToY8().Spline16Resize(width()/2, height()/2, src_top=0.375)
    even=YToUV(U, V, Y)
    raw
    selectevery(2,1)
    Y = ConvertToY8()
    U = UToY8().Spline16Resize(width()/2, height()/2, src_top=-0.375)
    V = VToY8().Spline16Resize(width()/2, height()/2, src_top=0.125)
    odd=YToUV(U, V, Y)
    interleave(even,odd)
    weave()
    
    
    
    dither_convert_yuv_to_rgb(interlaced=true, cplace="MPEG2", chromak="Spline16", mode=-1)
    RGB to DV-YV12 to MPEG2-YV12 to RGB
    Image
    [Attachment 64252 - Click to enlarge]




    The damage is so small, it's basically invisible for actual DV footage.

    Also you will find that using the script or letting the Cedocida DV codec handle the conversion to MPEG2-sited yields the same results, minus the difference in resamplers used.
    Last edited by Skiller; 12th Apr 2022 at 18:01.
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  24. Member Cornucopia's Avatar
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    Hmmm...it's visible here.


    Scott
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  25. Member Skiller's Avatar
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    @ Scott
    You mean there is a visible difference for you with actual footage, caused by the conversion? Note that my last post is strictly about PAL DV. NTSC DV to regular 4:2:0 is a 50% loss and quite visible.
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  26. There is tiny added blurriness on the horizontal lines. I would appreciate it you demonstrated conversion of NTSC DV into regular 4:2:0 using the same images as an example.
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  27. Member Cornucopia's Avatar
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    No I was referring to your reference pictures. They are certainly progressively worse from top to bottom.

    Scott
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  28. Member Skiller's Avatar
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    Originally Posted by ConsumerDV View Post
    There is tiny added blurriness on the horizontal lines.
    Yes. And it takes an extreme test like this (thin red on green) to see this.

    Originally Posted by ConsumerDV View Post
    I would appreciate it you demonstrated conversion of NTSC DV into regular 4:2:0 using the same images as an example.
    Good idea, I will do that later.



    Originally Posted by Cornucopia View Post
    No I was referring to your reference pictures. They are certainly progressively worse from top to bottom.
    Correct, but you really should only be comparing the second with the third image. It's the differences between the second and the third image that the conversion to regular MPEG2-sited chroma does to PAL DV.

    The first image is just the source in 4:4:4 RGB for reference so anybody can go ahead and do the same test on their own.
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  29. Member Skiller's Avatar
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    Here we go, 4:1:1 chroma test (NTSC DV).


    This is the source converted to 4:1:1
    Code:
    ImageSource("ChromaTest_RGB.png")
    
    dither_convert_rgb_to_yuv(output="YV411", chromak="Spline16", mode=-1)
    
    dither_convert_yuv_to_rgb(chromak="Spline16", mode=-1)
    RGB to 4:1:1 to RGB
    Image
    [Attachment 64253 - Click to enlarge]

    Looks surprisingly good I must say.




    And now the conversion of 4:1:1 to regular 4:2:0.
    Code:
    ImageSource("ChromaTest_RGB.png")
    
    dither_convert_rgb_to_yuv(output="YV411", chromak="Spline16", mode=-1)
    
    ConvertToYV12(interlaced=true, ChromaResample="Spline16")
    
    dither_convert_yuv_to_rgb(interlaced=true, chromak="Spline16", mode=-1)
    RGB to 4:1:1 to 4:2:0 to RGB
    Image
    [Attachment 64254 - Click to enlarge]

    As to be expected, this is quite a hit. But it's really not as bad as I would have anticipated.


    Edit: Better labeling.
    Last edited by Skiller; 12th Apr 2022 at 18:04.
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  30. Originally Posted by Skiller View Post
    But it's really not as bad as I would have anticipated.
    Thanks! I have downloaded the pics to better compare them. In a hindsight, it looks as expected: 4:2:0 reduced vertical resolution, 4:1:1 reduced horizontal resolution, and converting 4:1:1 to 4:2:0 reduced it all around.

    It feels that the difference between RGB-411-420-RGB and RGB-420-RGB is less pronounced than the difference between RGB-420-RGB and RGB-411-RGB -- 4:1:1 is very clean in vertical direction, and the difference to horizontal chroma resolution is huge.

    So I guess the original RGB source for 4:1:1 should be 20% smaller vertically, then after applying the conversion it should be expanded to the same vertical size as the 4:2:0 one. This way it would look more realistic.
    Last edited by ConsumerDV; 12th Apr 2022 at 20:58.
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