capturing analog (s-vhs or hi-8) as mov.dv

[bluesix]

I have been trying to find a solution to capture analog video (s-vhs + hi-8) without significant color loss. I currently capture dv avis from digital 8 camcorder to my pc. No matter how the conversion is handled, I still end up with color loss. Even capturing s-vhs with a s-vhs cable into my pc as uncompressed avis gives me the same problem.

I spoke with an expert at Compuplus and he recommended capturing as a quicktime file. In other words, a mov.dv format. Apparently that is an uncompressed or a loss-less quicktime codec. He said it was possible to do in windows. I have yet to find capture program that can handle that format. Supposedly there is a driver for premiere but I have not seen it.

Any ideas?

Running windows xp

[jggimi]

...Even capturing s-vhs with a s-vhs cable into my pc as uncompressed avis gives me the same problem....

Have you taken a look through the Analog Capture Guide (http://www.doom9.org/capture/start.html)? It looks like you've missed it, because you captured uncompressed rather than using a lossless codec such as HuffYUV.

In particular, Section 7 discusses color manipulations that may be of interest to you. Sections 7.1.1/7.2.2 cover chroma artifacts, and 7.1.9/7.2.9 cover color adjustments.

[Arachnotron]

I currently capture dv avis from digital 8 camcorder to my pc. I may be wrong here, but I thought digital-8 is a form of DV. If so, why are you trying to cap it uncompressed? It is already digitized by the camera and encoded to DV so it should be transferred in DV form too.

If you try to capture to another codec, the DV get's uncompressed first and re-compressed to the other codec afterwards. If your system uses a DV codec that gets the luma range wrong that might explain your problem.

There is more about this stuff in the DV forum.

[bluesix]

I am using my digital 8 camcorder to convert hi-8 to dv. The hi-8 footage was not shot on my digital 8 camcorder. It was shot 6 years ago on a hi-8 unit.

I did try huffyuv a year ago, and basically got the same results. The issue is not a redish or yellowish tint, it is a basic overall washout of colors through the spectrum. That is where this video tech guy firmly recommended the quicktime format to capture in. Aside from getting a MAC I was told I need to find a way to capture in mov.dv .

[jggimi]

I'm still confused about what you are seeing, and how you are capturing.

Capture "thru" DV is discussed in the DV forum, where there are experts on chroma subsampling who may be able to point to a problem and a solution. 4:1:1 is used with NTSC, and 4:2:0 is used with PAL. There are filters that can make chroma adjustments, and they may be helpful to you.

But, you've also said you capture analog, and have the same trouble (via a separate PCI card, or a VIVO card wasn't made clear). I've suggested reviewing the analog capture guide, you may see in the samples images in chapter 7 something that matches your particular issue.

[Wilbert]

That is where this video tech guy firmly recommended the quicktime format to capture in. Aside from getting a MAC I was told I need to find a way to capture in mov.dv .
My advice is not to listen to his advice. AviSynth/Vdub doesn't work on a MAC, so I have no idea about the postprocessing possibilities in that case.

it is a basic overall washout of colors through the spectrum.
Could you post some pics which shows this clearly?

[trevlac]

Originally posted by bluesix
That is where this video tech guy firmly recommended the quicktime format to capture in. Aside from getting a MAC I was told I need to find a way to capture in mov.dv

Did he sell Mac's ?

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Your problem is what you expect to see. A PC monitor does not display the same as a TV. In addition to this, what ever codec you are using to decode the DV on your pc might not be getting the color range correct. This might be a problem is you are going to encode to mpeg or filter the source. But, I'm not clear how you capture without the d8 cam so I wont go into this.

Here is a test ...

1) Output the svhs to the TV. Looks ok right?
2) Capture the svhs to the d8 tape.
3) Output the d8 to the TV. Still look ok?
4) "Capture" the DV from the D8 to the pc using firewire. This is basically a file copy.
5) View the DV on the PC. Looks bad right?
6) Copy the DV back to a new d8 tape using firewire.
7) Check it out on your TV. Looks ok?

If this is all true ... and you are going to view on a TV ... you are ok. Just adjust your pc. If you are going to make say a DVD ... run a test thru the entire process and check it out on the TV.

[bluesix]

Let me go over again my capture scenarios.

S-VHS source: Capture directly to pc from S-VHS deck via S-VHS cable. Capture format is uncompressed avi 720x480.

Hi-8 source: Capture from d8 deck to pc via firewire. Format is dv avi. The Digital8 deck handles the analog to digital conversion.

My desired output is for pc. It must look good on LCD and CRT computer monitors.

Yes the S-VHS source and the hi-8 look good on a regular tv monitor. On my computer monitors (CRT and worse LCD) there is color-loss and a general yellowish tint to everything. I have since been experimenting with the Vdub filter Color Equalizer v1.1 . Using amplification:

R 1.004
G 1.010
B 1.211

That seems to resolve the yellowish tint issue. I still seem to have to saturate the hell out of it:

hue/saturation/intensity[1.2] sat 1.39

I will post some screenshots in the next day or so.

The tech rep I spoke with was from Compuplus. They work mainly with MACs. From what I heard, most of the hardcore video editors use MACs for editing. He just re-affirmed it but suggested I try capturing with the quicktime codec.

[Sergei_Esenin]

First, DV is a 4:1:1 or 4:2:0 codec with poor color resolution in the first place, so it's not surprising it looks "washed out" on your PC. You said these are Hi8 (which is analog) tapes played back on a Digital8 camcorder to your PC or TV--meaning that when you're viewing on your TV you're getting unrecompressed analog playback, yet when viewing on the PC you're having it compressed with the DV codec and its awful reduced color sampling. *That* is most likely the source of your problem, and the idiotic salesperson's notion of getting a Mac (which is *not* what pros use, it's what low-end pro-ams use) won't fix it.

That's unless you simply have your monitor or TV calibrations off, which may be the case. Your monitor may be undersaturated or your TV oversaturated, causing disparity. You should especially calibrate your TV with Digital Video Essentials or Avia, because unless you do it's entirely useless for comparisons since TVs are almost always set incorrectly--even from the factory. As for monitor calibrations there are many methods; I just use the calibration tool included with Adobe Photoshop, but if something like that isn't available to you you can check basic contrast and gamma by going here:

http://www.jasc.com/support/kb/articles/monitor.asp

You mentioned capturing "directly to pc from S-VHS deck via S-VHS cable." What capture card are you using? Or are you also passing this through the Digital8 camera first? Even if the S-Video cable goes directly from the VCR to your PC, there's a capture card there.

What you need is a *good* uncompressed capture card with a recent Conexant or Philips chipset, like for example a Leadtek Winfast TV2000XP Expert or LifeView FlyTV 2000 or Platinum. Capturing from S-Video in lossless huffyuv using one of those will give you the best quality you can get for your S-VHS and Hi8 tapes.

[trevlac]

Originally posted by bluesix
Let me go over again my capture scenarios.

S-VHS source: Capture directly to pc from S-VHS deck via S-VHS cable. Capture format is uncompressed avi 720x480.

Hi-8 source: Capture from d8 deck to pc via firewire. Format is dv avi. The Digital8 deck handles the analog to digital conversion.

My desired output is for pc. It must look good on LCD and CRT computer monitors.

Yes the S-VHS source and the hi-8 look good on a regular tv monitor. On my computer monitors (CRT and worse LCD) there is color-loss and a general yellowish tint to everything. I have since been experimenting with the Vdub filter Color Equalizer v1.1 . Using amplification:

R 1.004
G 1.010
B 1.211

That seems to resolve the yellowish tint issue. I still seem to have to saturate the hell out of it:

hue/saturation/intensity[1.2] sat 1.39

I will post some screenshots in the next day or so.

The tech rep I spoke with was from Compuplus. They work mainly with MACs. From what I heard, most of the hardcore video editors use MACs for editing. He just re-affirmed it but suggested I try capturing with the quicktime codec.

This is good info. Still missing what your capture card is ... but I don't think that is the problem.

1st Let me restate the purpose of my test.

If you digitize using the D8 cam and then play the cam back to the TV, you are playing a DV compressed digital source. If it looks good, the DV compression nor the Analog to Digital conversion are a problem. If you then copy via firewire this source to your PC, it is exactly the same as what was on the tape. So... if you view it on the PC, and it looks bad, the difference is the viewing monitor (TV vs PC).

I believe this is the problem. The real problem then is that you wish to view your final output on a PC. Next question is what is your final output and how will this be played (what software player)? For example, if you make a dvd and use something like powerDVD or WinDVD or many others, these players will adjust for the fact that a TV has a cranked up saturation and a PC monitor does not.

If you don't know how it is going to be played ... you have some trouble. You can search the net for gamma and see that this is an issue for artist because there is no common viewing device on the net. And they don't like the differences.

BTW: Mac's are again different. If you've ever viewed anything on a Mac and a PC, you'll see the colors are different (again). So composing on a Mac for PC viewing poses problems.

Hell ... TV to TV is different. Some have really cranked up reds. I doubt most people have good PC monitors that they adjust also.

Finally, you could have a codec problem in the playback on the PC. I doubt this because you say even uncompressed is the same.

Bottom line .... If the capture is fine you can adjust the playback monitor or adjust the video.

-------------
Full disclosure. I don't have a Mac. I have a PC. And hardcore video editing is done on both. If you get to the really high end stuff, a Mac bundle is probably cheaper.

[trevlac]

Originally posted by Sergei_Esenin
First, DV is a 4:1:1 or 4:2:0 codec with poor color resolution in the first place, so it's not surprising it looks "washed out" on your PC. You said these are Hi8 (which is analog) tapes played back on a Digital8 camcorder to your PC or TV--meaning that when you're viewing on your TV you're getting unrecompressed analog playback, yet when viewing on the PC you're having it compressed with the DV codec and its awful reduced color sampling.


I agree with all your other comments ... but not this.

Hi8 or SVHS is not "uncompressed". The bandwidth of the color is quite a bit lower than that of the luma. I don't recall the spec, but I'm sure 4:1:1 and 4:2:0 are more than adiquate to produce a good color picture. After all, a DVD is 4:2:0.

If you record something on a D8 cam, it is compressed DV. I would be quite surprized if playback of a Hi8 recording to a TV vs playback of a D8 recording to a TV was much different on a given cam.

[Sergei_Esenin]

Originally posted by trevlac
I agree with all your other comments ... but not this.

Hi8 or SVHS is not "uncompressed". The bandwidth of the color is quite a bit lower than that of the luma. I don't recall the spec, but I'm sure 4:1:1 and 4:2:0 are more than adiquate to produce a good color picture. After all, a DVD is 4:2:0.

I clearly said "unrecompressed," as in not recompressed from analog to lossy DV. And no, 4:1:1 or 4:2:0 sampling is *not* enough to capture a good analog source without color banding and loss of vibrance. For example, my laserdiscs and S-VHS home videos with bright reds and greens look *awful* captured to 4:1:1 DV, but *excellent* captured with a 4:2:2 sampling. Someone here on Doom9 used to have a great picture posted using a *Star Wars* laserdisc to compare 4:1:1 color anomalies with DV passthrough vs proper 4:2:2 analog capture with a Lifeview Flyvideo 2000, but it isn't on his site anymore.

And DVD's 4:2:0 colorspace cannot be compared in any way because the original capture and sampling processes used in the source mastering are 4:4:4, or 4:2:2 at the low end, and typically begin at much higher resolutions for studio materials. Colorspace and resolution values are downsampled later. Capturing analog data directly to 4:1:1 or 4:2:0 is very different, because supersampling and then downsampling always produces better results than direct sampling. It's the same with colorspace as it is with resolution: starting with a larger sampling than your final output format, and downsampling later, gives better results.

There's a lot to be learned by reading about sampling theory. While not directly applicable, pages about Nyquist's theorem generally have some observations with broader appeal

If you record something on a D8 cam, it is compressed DV. I would be quite surprized if playback of a Hi8 recording to a TV vs playback of a D8 recording to a TV was much different on a given cam.

No, read closer. He says:

I am using my digital 8 camcorder to convert hi-8 to dv. The hi-8 footage was not shot on my digital 8 camcorder. It was shot 6 years ago on a hi-8 unit.

That is the most important detail. So, everything I have said is true, about his TV getting an unrecompressed analog signal but his PC getting downsampled colorspace with DV compression. Digital8 cameras, at least the Sony I'm familiar with, playback Hi8 over analog S-Video without showing DV compression artifacts--the DV compression is done later in the camera circuits.

BTW: Mac's are again different. If you've ever viewed anything on a Mac and a PC, you'll see the colors are different (again). So composing on a Mac for PC viewing poses problems.

Hell ... TV to TV is different. Some have really cranked up reds. I doubt most people have good PC monitors that they adjust also.

That's the purpose of calibration. A properly calibrated PC display will show almost exactly the same thing as a properly calibrated Mac display, and any properly calibrated TV will show the same image characteristics as any other properly calibrated TV. Calibration tools like Digital Video Essentials and Adobe Gamma are invaluable, though underused.

[trevlac]

Sergei

I'm not sure if you are disputing everything I am saying ... and I'm not sure if you have practical experience or are working with theory.

I have some practical (limited to the equipment I have) and recently try to stay away from the theory ....

Anyway ... to restate my points.

On the test: The purpose is to cut out the PC. You can run a test by just playing svhs->D8->TV. If it looks ok, it is not the DV and it is not the ADC.

On is 4:1:1 or 4:2:0 good enough ... SVHS color bandwidth is 0.629MHz and Hi-8 is 0.743MHz according to Video Engineering by Andrew Inglis.

By comparison ... the bandwidth of the luma portion of an SVHS signal is close to 4MHz. Or in digitial terms ... SVHS is about 4:(0.63):(0.63). No doubt when this goes thru an ADC the signal is supersampled at probably a 27MHz rate for both Luma and Chroma on a Sony (is there any other kind?) D8. Then both are downsized to 13.5MHz and 3.375MHz respectively for 4:1:1 DV. And yes these digital numbers should be at least 2x the analog bandwidth (shannon theory stuff) and preferably more. Point is, there is more room for the chroma than for the luma.

On calibrated monitors: .... Anybody who has used video esentials and such on a couple of TV will be able to tell you that TVs are different from each other and source input is different from each other ... and DVD players output different levels ... not just on theory but on the practical of the hardware. Heck go to a TV store and see how different the color characteristics are from one TV to the next.

You will never get a PC monitor to look like a TV. Different hardware for different purposes. Different signal. If you read a little about color correction you will find that the color of the paint on the wall in your viewing room, and the room lighting make a huge difference.

---------------------------
Well ... I said more than I really wanted to. :)

I did want to add. If you run the Test and the D8(DV) has less saturation and poor colors on your TV (VS the SVHS), your ADC/DV could well be the problem. I don't think so since you feel uncompressed is just as bad as DV on your PC. I think it's the monitor.