VHS quality is = to VCD/SVCD?

[Anonymous65]

I used to capture at 720x480 for VCD creation, but I didn't like bluryness from the deinterlacing process. So, I now capture all my VCD video at 704x240. This gives a much better image than capturing at 352x240, believe it or not. The internal scaling of the BT8x8 chip is terrible, so I let TMPGEnc or Virtualdub do the reduction to 352. Another reason for capturing at 704 instead of 352 is that TMPGEnc creates less compression artifacts with a 704 captured file. I have tried all kinds of methods for VCD creation, and have found the 704x240 mode best for VCD video.

[txpharoah]

I used to capture at 720x480 for VCD creation, but I didn't like bluryness from the deinterlacing process. So, I now capture all my VCD video at 704x240. This gives a much better image than capturing at 352x240, believe it or not. The internal scaling of the BT8x8 chip is terrible, so I let TMPGEnc or Virtualdub do the reduction to 352. Another reason for capturing at 704 instead of 352 is that TMPGEnc creates less compression artifacts with a 704 captured file. I have tried all kinds of methods for VCD creation, and have found the 704x240 mode best for VCD video.

Ummm... wow... where to begin...

1. VCD is locked at 352x240 MPEG1. Nothing else.
2. You can interlace at any MPEG2 resolution above 352x280.
3. You can capture just as well at 352x480 as you can at other resolutions, at least on most cards most of the time. Often the "quality difference" is psychologically perceived rather than on-screen.
4. 704x480 is not a resolution accepted by many authoring applications.
5. Compression artifacts are related to your bitrate, not resolution.
6. Only BLENDED/DOUBLE deinterlace is blurry. Other methods drop fields.
7. Do what you want, but you may be making this harder on yourself than it should be.

[malducci]

@ Satstorm

The more I read through your explaination, the more I see how your are describing the interlaced system. Why you don't use offical terms like scanline or fields is strange.

Fact - both NTSC and PAL *ALWAYS* have the same vertical scanline resolution regardless of the source. NTSC has 480 visible scanlines and PAL has 576 visible scanlines.

Fact - a VHS regardless of the grade or mode has to output to xxx by 576 PAL or xxx by 480 ntsc.

Fact - PAL displays 50 field per second. NTSC displays 59.94 fields per second.

Fact - one field is displayed on an even scaline, while the other field is displayed on an odd scanline

There is no such term as a non-active line. The only thing I can think of that you mean - is when the current field is drawn, then the previous field is still on the screen ( but is fading on a real TV set due to the phosphorus ).

Fact - if you are capturing @ xxx by 288 PAL or xxx by 240 NTSC - you are infact throwing out WHOLE field of video AND this is DEINTERLACING - its called DISCARDING ONE FIELD - wheather you know it or not. If you capturing @ xxx by 288 then you ARE deinterlacing the signal by discarding one field and that's a fact.

Oh, and if your source video in VHS is home movies - you are ALSO throwing out half your temporal resolution because VHS camcorders are shot in 50 fields fer second PAL or 59.94 fields per second NTSC - that's a fact too.


PS: I never said 100fps.com was a bible - it's just a site that explains what fields are.

[MrKGB]

I used to capture at 720x480 for VCD creation, but I didn't like bluryness from the deinterlacing process. So, I now capture all my VCD video at 704x240. This gives a much better image than capturing at 352x240, believe it or not. The internal scaling of the BT8x8 chip is terrible, so I let TMPGEnc or Virtualdub do the reduction to 352. Another reason for capturing at 704 instead of 352 is that TMPGEnc creates less compression artifacts with a 704 captured file. I have tried all kinds of methods for VCD creation, and have found the 704x240 mode best for VCD video.

Ummm... wow... where to begin...

1. VCD is locked at 352x240 MPEG1. Nothing else.
2. You can interlace at any MPEG2 resolution above 352x280.
.......
7. Do what you want, but you may be making this harder on yourself than it should be.

txpharoah,
I think you are confused a little bit here.
skittelsen was saying that he is CAPTURING at 720x240, and it is well known that it is a good idea to capture at a higher resolution for NTSC, and then resize.
704x240 is maybe an overkill, but the idea is right.

[MrKGB]

Don't mention the horror called "SECAM" (System Even Crapier America's). Have you ever tried cap and encode secam?

What is wrong with secam? isn't it the same as PAL as far as computer video concerned? I have done few projects with secam, didn't have any problems.
@SatStorm, I think you should understand this: "Kak nizko PAL SECAM"

[malducci]

Sorry,

I forgot to mention the exception: 2-2 PULLDOWN ( not 3-2 ). This is a popular movie to video method for PAL - pretty rare for NTSC. 2-2 pulldown is a film shot @ 24fps speed up to 25fps and then divided into two fields @ 50 fps - capturing 2-2 pulldown @ 25fps XXX x 576, with the right field order automaticly puts the video back to progessive frame. There is no deinterlacing to be performed, but discarding a field will still lose half the vertical resolution

This does not apply to VHS camcorders - only expensive cams( $5000+ DVPRO ) can record in frame mode 8)

Working with a lot of VHS cam footage lalely, I totally forgot about 2-2 pulldown

[Anonymous65]

Since I have some free time, I'll reply

>Ummm... wow... where to begin...

>1. VCD is locked at 352x240 MPEG1. Nothing else.

That is correct. The VCD has to be 352x240. However, you can capture at whatever resolution you want.

>2. You can interlace at any MPEG2 resolution above 352x280.

To deinterlace, you have to have both fields, that means x480 for NTSC and x576 for PAL 4:3 video. Any other vertical resolution does not capture both fields and cannot be deinterlaced.

>3. You can capture just as well at 352x480 as you can at other resolutions, at least on most cards most of the time. Often the "quality difference" is psychologically perceived rather than on-screen.

Capturing one field instead of two drops the CPU load, and also droppes the hard drive space by half.

>4. 704x480 is not a resolution accepted by many authoring applications.

No authoring application will use 704x480 or any other resolution other than 352x240 for making a VCD. For TMPGEnc to rezise to 352x240, only 704x240 will resize correctly. 720x240 will not resize correctly to full screen 4:3 video.

>5. Compression artifacts are related to your bitrate, not resolution.

That is not correct. The resolution of the video fed to the encoder will also have a great effect on compression artifatcs. See my web page for test results using different capture resolutions for making a 352x240 VCD. http://steve.kittelsen.com/vcd

>6. Only BLENDED/DOUBLE deinterlace is blurry. Other methods drop fields.

Dropping fields is the same as capturing one field only. Why capture both fields and then drop one before encoding? That is a waste of hard drive space. There are also deinterlacing filters that will not blur video unless there is a lot of motion. However, this filter does normally not work during capture.

>7. Do what you want, but you may be making this harder on yourself than it should be.

The goal is to make the best looking VCD that is possible, no matter how hard it is

[malducci]

I know what you mean skittelsen. Captured 704 x XXX looks better than 352 x XXX -> scaled to 704 x XXX or vice versa.

If I remember correctly, the BT848/BT8x8 internally always capture @ 704x480(ntsc) and then internally scales the horizontal resolution to whatever was requested. As far as the vertical resolution, I can only speculate that there is two modes - full frame with two fields capture( no scaling ) and single field mode which can accept scaling(reducing) parameters. I think IUlabs site had info on this - note sure.

[Anonymous65]

Yes, as far as I know, the BT8x8 chip should be capturing at full resolution all the time (720x480 for NTSC) and then do the scalling internally. However, if this was the case, the image captured at 352x240 and a image captured at 720x240 and then scaled to 352x240 in Vdub should look the same. But, they don't! The image scaled by the BT8x8 look a lot worse than the image scaled by Vdub (no matter if you select linear or bicubic mode). So, the math or horizontal scaling used in the BT8x8 must be very poor. Also, the BT8x8 chip is not capable of scaling from two fields to one (deinterlace). The RAGE Theatre chip used in the older ATI All in Wonder cards could do an internal scalling from 2 fields down to one, and made nice looking x240 captures (adaptive deinterlacing).

[txpharoah]

Having read the responses I just got, I don't think any of us are talking about the same things.

And it'll take too long to go back and sort out. So I'll move forward. I feel sorry for anybody trying to learn from this thread. I even had to re-read a few things to make any sense out of it.

I'll jsut ramble a few things off here:

1. Don't forget that VHS tapes may be fed data, but they don't necessarily record it. The broadcast signal is stronger than the tv's ability to intercept, as is the tv stronger than the VHS recording. Remember, we're talking magnetics and analog here, not digital and bytes.

2. And as odd as it seems, we've all got good facts on interlace, but none of us are talking about the same identical situations. Some of the capturing and deinterlace info is a bit off too, but again, trying to sort all that out would require time and Advil.

3. VHS does not output to a rigidly set scanlines rate. Nor is it scientifically accurate.

4. Deinterlacing can also merge fields, not just discard them.

5. 352x280 is an interlaced format for PAL DVD video and computer video.

6. Capturing at frame rates double+ the desired size is not suggested. Theory and some applicable reasons exist for doing it, but not when you're using tv or VHS as source. This would take a while to explain.

7. After you arrive at 352x480 video, artifacts are normally bitrate-related at that resolution and those beyond it. Especially when viewed on a tv. The max signal that can possibly be output'd by a s-video cable is 352x480, and that's pretty much the best video cable yo can get from VHS or consumer equipment. Capturing above that will almost never make any difference in the quality of the final product.

[SatStorm]

@malducci
I'm blessed not being an American and I'm lucky enough that English isn't my native language. So, I don't know the english techical words for many terms. That doesn't mean that I don't know what I'm talking about. I don't have the skills to express it in pure english. That's it. As I said many times in the past in this same forum, I learned english all by myself, by watching MTV Europe, 15 years ago (1988). Never went to an english school amd I don't have a simply paper state that I know english. Officially, I don't speak the language.... I can't even proove that I know the language if a paper is needed for -let say- a job.
Now: How many non - english speaking people you see posting and leading (as I do) english speaking technical forums? Very few. Did you ever wonder why this is happening? Because it is twice difficult to express yourself technically in a foreigh (for you) language, than simply chating in a foreign (for you) language. And for me, English is a foreign language. How many Germans (a nation which are monsters of technical knowledge) or French people (a nation with great studies and education system) you saw posting here ? Not so many. From the other hand you see many people from US, UK, Australia, even India. The non English by birth leading members of this board are very few. Why? Not because French and Germans don't care for those stuff. But because they can't post their thoughts in english well.
This situation has this effect in this board: The 65% here use NTSC and they are americans, while the 35% are from other parts of the world, using variations of PAL or even that terror called SECAM. You know what's the problem is here: We, the PAL people have to "convert" all the knowledge you, the NTSC people gather and post here. Unfortunatelly, this works only partly... From the other hand, when we, the PAL people try to talk about PAL, you, the NTSC people, pop up with claims and Facs and States and Terms you and only your system (NTSC) follows or need to do the job done. Plus, your totally different approach of any subject, your totally different view of anything and the overall totally different way of thinking and expressing of yourselfs, basicly because of your coulture and the "based on Maths and only" education system you have, can't realise global or different approaches/ expressions or even terms or points of view, except the ones you know, learned "from trustfull sources" or show with your own eyes. This is the so called "aglosaxon" characteristic you have and thats why it is so easy to be controlled by the mass media nowdays. "I saw it on TV, it has to be real" the Americans 20 years ago use to say. Today this turned as: "I show it on the XXXX trustfull internate site, they know, what the hell are YOU talking about". I well know this approach of yours: When I first posted for CVD in this same forum, many americans send me emails stating that I'm an ******* and I don't know what I'm talking about, I'm misleading people to non justified facts, etc. Thanks God, I prooved by anyone later on everything and they stopped. But that don't change the FACT that the "no fancy european guy which don't even know english well and don't even have a fancy site by his own" which I am, was not the total jerk many americans use to name him, just because he didn't link them to "facts" from "realable" sources. Bullshit. Like this DVDplus.org site or some stupid others... Fancy looks, bullshit inside. I stop here.

Plus, in Europe we use sometimes different words (terms) in english for the same thing. So I describe what I can in the way I can with the limited knowledge I have in this language (English). Guess what: Mostly non americans don't have problem with that. Americans do.... They try hard not to understand what I'm talk about.
Sorry for that. A non english-speaking European is far less smart a mainstream American. It is really impossible smart American people understand what us, the stupid non english-speaking people try to say. :lol:

Anyway

As txpharoah said, we talking totally different things here.
And also, trying to expain PAL with NTSC in mind (or vice versa) is totally wrong.

Try to realise something for VHS: VHS doesn't output CCIR. It is output CCIF. But in analogue you need to output CCIR. So, the cheap trick is to output 2 CCIF frames in the raw, in an offset position between them.
That result a (fake) full CCIR output . You needs 4 fields / 2 frames to do this. That is VHS in short terms.
So when you encode to digital, or you reconstuct the CCIF output (capture 352 X 576, reconstruct to 352 X 288 using whatever techique you want - nothing to do with de-interlace) or you emulate the CCIF to CCIR cheap trick (capture 352 X 576, filter, encode to 352 X 576)
That is for PAL a cheap and good trick. As txpharoah said, "we are lucky bastards" :lol:

[malducci]

Sorry, SatStorm I was not my intention to offend you - nor did I judge you, as you have apparently have already judge me based on your post.

I was simply trying to state that there was a miscommunication based and terms used. I know what I know about NTSC because I have to - its not just a hobby and I know it from experience. I have read manuals and books on NTSC singal generation having built video generating circuits projects, video conversion, and editing/special effects for low-budget independent films. I do not proclaim to know everything about any one subject.

I couldn't find any sources explaining the PAL VHS format storage method other than your posts. Obviously PAL is not my stronge point - living in a NTSC country. I have done PAL to NTSC conversions, just never from VHS

I only stated facts so we could be on the same terms. I would like to continue this conversation via private message or email if you would agree

[Gazorgan]

If ya'll are bored, try using VCD resolution, but in MPEG2 codec and VBR. Some real amazing results, and a way to get 90 minutes on a CDR. Good for Kids programing, or something I want to watch from TV later. this is limited to 25" or less TVs, otherwise you can really tell.

Thank god for my $50 US DVD player that plays dang near anything I put in it!

[txpharoah]

I only stated facts so we could be on the same terms. I would like to continue this conversation via private message or email if you would agree

No, no. Keep it here. This is what these forums are for, after all.

Or at least include me in the PMs/emails. I think I may learn a few things myself from this analog conversation. I left analog and had digital foisted onto me before I learned everything I wanted to know about foreign (and even some aspects of NTSC) analog video. Keep going guys, I'll read and chime in myself if needed/wanted.

I'm sure others could pick up some good knowledge too from this thread.

[Sefy]

@Gazorgan, you do know what you said, i've implemented in a template for TMPGEnc nearly 2 years ago ? does SxVCD ring a bell

@SatStorm, Well Said!

[SatStorm]

And I still heavily using a "SxVCD"-like template myself today, even on my DVD-Rs.
Remember Sefy some months ago, I replied you that this SxVCD of yours was a great idea and DVD compatible (if you use the correct GOP)? Well, months later, this is "official" because a well known US based site for our hobby says so. When I was said it, nobody believed me!
I hate this. And unfortunatelly, it happens all time!

Anyway, just for the info: SxVCD is still the best solution IMHO for VHS to DVD transfers! We might need a few more steps for perfect results than going CVD, but you can fit 7 hours on a DVD Disc that way, in true PAL VHS quality! If that isn't something, then what is!

Also, this discussion has nothing new to offer. Do a forum search and others have already answered in much better english than mine, all the infos for this subject!

[indolikaa]

Go CVD for NTSC VHS conversions. It rocks.

I would like to make some comments regarding certain I've seen on this forum, and this website in general.

This website is for "we" as a community to share ideas and insight into this hobby we have invested time and money into. I don't come here looking for anti-American bashing, anti-European bashing, or any bashing in general. I do not enjoy having to read through this kind of crap to find the information that makes my video pursuits more enjoyable. This is childish!

Nobody on this board is God's duly-appointed expert on video. If you think you are, go solve the bigger problems this world faces. Or post under your Avatar your credentials (i.e., where you got your Ph.D., patents pertaining to subject matters found on this website, etc.) so that we "dont-know-shnit" newbies can try to make heads or tails of who to believe.

SatStorm, I happen to have read your CVD primer and found it to be the single most helpful piece of writing I've found on this website! You notice I refer to it as CVD, not 1/2 D1? I'm not too proud an American to give China credit where credit is due. I am really disappointed and somewhat upset that you felt the need to lash out against Americans, which I happen to be. Now if you choose to single out an individual worthy of European contempt, more power to you. Just don't classify all of us as heathen American bastards.

[txpharoah]

lots of words

Huh?

[indolikaa]

I didn't stutter. And you Ain't with Stupid. So point that thing somewhere else, PAL.

[raldasec]

PAL. i get it.

if indolikaa is done and would step off soapbox for a moment, i have question about vhs transfers.

reading stuff leads me to believe vhs is in theory equal to vcd. i have many s-vhs recordings so what format is s-vhs supposed to be equal to?

[adam]

S-VHS is roughly equivalent in quality to SVCD. That would at least be the most comparable digital format.

[txpharoah]

S-VHS is roughly equivalent in quality to SVCD. That would at least be the most comparable digital format.

Actually, I'd call it equal to CVD or Half-D1 DVD.

[indolikaa]

Very confused here!

VCD = 352 x 240
CVD = 352 x 480

I didn't think SVHS was that much better, let alone double. I thought LaserDisc was a lot closer to CVD than SVHS was. This confuses me; if SVHS is close to CVD, then where is LaserDisc?

[raldasec]

i dont know. i have recorded here two discs from tape that was recorded in svhs camera. one disc is svcd and second disc is cvd. i made both discs direct from the capture (dvc2) and i dont know if i can tell the difference. there seems to be less pixels from cvd disc but it looks not quite as sharp. hard to tell and this is on a sony xbr32 tube.

btw: i think i read ld is between svcd and dvd. i use dvd at maximum rate that will fit one disc. this is vhs thread, go find ld thread to play at! :P

[txpharoah]

Very confused here!

VCD = 352 x 240
CVD = 352 x 480

I didn't think SVHS was that much better, let alone double. I thought LaserDisc was a lot closer to CVD than SVHS was. This confuses me; if SVHS is close to CVD, then where is LaserDisc?

SVHS is about 400-420 lines.
VHS is about 220-240 lines.

These are the DIGITAL equivalents.
VCD = 352 x 240 = ~VHS/8mm
CVD = 352 x 480 = ~SVHS/Betacam

Broadcasters use SVHS and Betacam for non-live recordings that are taped. It is WAY better than VHS. Even the tapes are constructed better (and different).

[indolikaa]

OK. What about the first number? My Dazzle has A LOT of different choices for the first number. I see that CVD is 352. I know that DVD/DVB is 704 or 720. Does increasing this number really make any difference when your source material is VHS/SVHS?

I'll milk these tapes for every electron I can reasonably get, but CVD does allow for several hours on a single DVD. The tradeoff between quality and keeping the number of discs on my wife's bookshelves to a minimum (happy wife=happy husband) might be appealing!

[txpharoah]

OK. What about the first number? My Dazzle has A LOT of different choices for the first number. I see that CVD is 352. I know that DVD/DVB is 704 or 720. Does increasing this number really make any difference when your source material is VHS/SVHS?

I'll milk these tapes for every electron I can reasonably get, but CVD does allow for several hours on a single DVD. The tradeoff between quality and keeping the number of discs on my wife's bookshelves to a minimum (happy wife=happy husband) might be appealing!

The "first number" is negligible in analog. It is latent, invisible, unimportant. The scanning doesn't work that way. But it is approximate to ~300 lines. That first dimension is really a product of digital video. 720x480 is actually a bastard resolution anyhow.

At 352x480, you are already capturing at a rate higher than the VHS or SVHS source, so to capture VHS/SVHS at a rate over 352x480 would just be a waste of pixels and bitrate. It is a wiser move to capture 352x480 at 4.0 MB/s rather than 720x480 and taking a bitrate under 8.0 to make it fit on the disc. The 352x480 4.0 MB/s is the same quality as 704/720x480 at 8.0MB/s because the bitrate per pixel is the same.

So lower resolution is not really "quality loss". Done correctly, it is actually a quality improvement, given that your source is VHS/SVHS.

[adam]

Actually, I'd call it equal to CVD or Half-D1 DVD.

Same difference as far as I'm concerned. CVD is almost literally equal in quality to SVCD. One has lower res but higher bits per pixel, and the other has the exact opposite in the exact same proportion. They are really identical in "quality" their differences just make them better for different situations/preferences.

I think SVCD is a more applicable comparison since it is, after all, the format that orphaned the other and became the worldwide standard, and also if you look at the press releases for SVCD and the technical documents on mpeg.org and berkley, SVCD was marketed as being equal in quality to S-VHS and these two formats are pretty much universally considered the analogue/digital equivalents of each other. CVD is simply forgotten as an official standard, it is simply incorporated into the finalized SVCD standard. (Actually its called SuperVCD but nobody uses that. SVCD +CVD became SuperVCD.)

[indolikaa]

OK. That makes some of the loose ends in SatStorm's primer make more sense. What about bitrate?

It was my understanding that, as a legal DVD resolution, 1/2 D1 as it was adopted was limited to 2744kb/s for video and audio. Anything higher, and you were at the mercy of the DVD player processor. The "home movies" will be duplicated and sent to relatives, so I want to make sure I stay within the legal limit. Again, your input is welcome.

And by the way, thanks for your help. Some of these videos are absolutely priceless to my family, and they will have to be converted to whatever format they use back home. I doubt its NTSC.

.indolikaa.

[txpharoah]

legal DVD resolution, 1/2 D1 as it was adopted was limited to 2744kb/s for video and audio. Anything higher, and you were at the mercy of the DVD player processor.

DVD, no matter the compliant resolution of the MPEG2 (including 352x240, 352x480, 704x480, 720x480 - NTSC numbers), it supports a max of 10.08 MB/s (combined audio+video). MPEG1 has a max of 1856k and only 352x240.