Calibrating luminance levels/color for capture from VHS

[sanlyn]

Cherbette, can you tell us the original image ratio on your source? The downloaded AVI had been resized to 700x473. That's a 1.4799 image ratio, which doesn't match any common film format. The only reason I know for cropping was that the original was wide-screen letterboxed on a 4:3 screen. I couldn't do the math to make my mpeg letterboxed, if that's the way it looked originally. So I just made it 4:3 rather than drive myself nuts.

[Cherbette]

Thanks So I just copy that AVS file to the Avisynth plugin folder? I guess I was looking for a ".dll" so I'm unsure what to do with the AVS file

[Cherbette]

Cherbette, can you tell us the original image ratio on your source? The downloaded AVI had been resized to 700x473. That's a 1.4799 image ratio, which doesn't match any common film format. The only reason I know for cropping was that the original was wide-screen letterboxed on a 4:3 screen. I couldn't do the math to make my mpeg letterboxed, if that's the way it looked originally. So I just made it 4:3 rather than drive myself nuts.

Never mind. I looked it up. Cher's original DVD was 1.78:1, so a tape might have been letterboxed. So my MPEG is slightly squished. Oh, well...If I did this again, I'd have to make borders to frame size, uh...Too much to handle right now. It would have to be an MPEG at 740x480 to display at 16:9. My bad. But at 16:9, that 1.4799 image will look stretched.

When capturing that clip I simply used the "cropping" tool during capture in VirtualDub because I noticed when I was trying to adjust the brightness/contrast viewing the histogram that it was reading the line at the bottom and the borders on the side. I was going to ask how to best way to treat those borders that show up on the left and right hand side and on the bottom as well. Here's an example:


To answer your question regarding the ratio on the tape itself, I don't think it's letterboxed. I believe it's simply full screen and normally I capture at 720x480 and I've pondered to myself whether that's the best for capturing from VHS. Sanlyn your results are GREAT. I've got so much to learn about Avisynth. Scripts have always been a nightmare to me but I'm trying to learn Starting to get the hang of it...

[sanlyn]

Yep, AviSynth has a learning curve.

MCTemporalDenoise is a script, not a dll. You can load it by either pasting the script of the MCTemporalDenoise function into the AVS file you use to open the video, or you can copy the text of the script itself into a text file and name it "MCTemporalDenoise.avsi". Copy the avsi file into the AviSynth plugins folder. avsi files load automatically when your master AVS script to opens the video.

the MCTemporalDenoise link has a preface in its top "Comments" section (lines starting with "##"). You don't need the comments in your script (just the text of the function itself, which is pretty long). But those comments list the badditional pluigins and scripts required by MCTemporalDenoise. The script runs at about 2 fps in VirtualDub, about half the speed of NeatVideo. You'll likely get the same results I did. It works only with YV12.

Most VHS captures can be cleaned up fairly well by calling the MCTemporalDenoise function with a commonly quoted "default" statement. Here's the one I used yesterday; doctor it for whatever you name your video:

AviSource("G:\forum\LovePain\LovAndPain_RGB.avi")
AddBorders(2,4,2,3).AssumeTFF().ConvertToYV12(inte rlaced=true).MCTemporalDenoise(settings="low", edgeclean=true, ecrad=3, stabilize=true, maxr=2)
in2=last

The statement following "AViSource" has no carriage return; it's one unbroken statement. Make sure your text editor doesn't have auto-wrap turned on when you write AVS scripts. A carriage return in the middle of a statement will generate an error.

Before you can run MCTemporalDenoise, you have to load all its required plugins and scripts into AviSynth plugins. As I say, MCTemporalDenoise and NeatVideo gave such similar results, I had to make captures in photoshop and could still see little difference. MCTemporalDenoise had a bit less chroma noise, but they were still visible. So some kind of chroma cleaner would still be required (I didn't use one) along with bad-frame fixing.

When learning AviSynth, test scripts one at a time. When you see you're getting what you want, add the next script or plugin. You'll get the idea in a short time, and it will be less of a hassle when you see what various plugins do. VirtualDub "learns" the same way.

[Cherbette]

There's been alot of discussion here on how much a VCR with a TBC will help...I also have a DVD-R (I haven't used it in forever I think it's Panasonic) what are the odds that it would have a built-in TBC that I could use as a passthru? I would capture directly to the DVD-R but of course it doesn't offer uncompressed AVI

[sanlyn]

I would capture directly to the DVD-R but of course it doesn't offer uncompressed AVI

It won't clean up any problems, either. Once the noise and other glitches get compressed to MPEG, you'll need more than AviSynth, VirtualDub or Premiere to fix it. And those TBC's don't fix everything.

What's the Panasonic model? It doesn't even matter if the disk drive is busted, as long as input and output are OK. Use line 1 Input only, on Panasonics; there's no active TBC on the other Panny inputs. Do NOT use any Panasonic filters on input or output. You can use s-video for output (it's a good composite-to-svideo converter, IMHO). DMR-ES10, DMR-ES20, ES15, most of the ES series and later, and probably the upper-scale new Panasonics or Toshibas have built-in TBC's you can use as pass-thru (I think Toshiba's better, but they both work). Not all DVD recorders have TBC's, nor can all of them be used as pass-thru. Some older JVC's will work, too, I believe.

[jagabo]

Make sure your text editor doesn't have auto-wrap turned on when you write AVS scripts. A carriage return in the middle of a statement will generate an error.

And also be aware the forum software here inserts random space characters in long lines! Notice the space between the e and the r of the word "interlaced" in the script in sanlyn's post. If you copy/paste from a post you may need to fix those.

[sanlyn]

I forgot to say earlier4, cherbette, MCTemporalDenoise is somewhat more than a denoiser. Using its many features, though, means getting into documenration for all its included filters (Documentation? Who reads documentation?). NeatVideo fixes several kinds of noise, but it's a denoiser-only. Ain't free, either.

[Cherbette]

I'll have to see which model it is...I know it's a part of the DMR series but I cannot recall which one. It's in storage...so I'll go check it out soon

[jagabo]

Another thing you can do is use heavier filtering on the chroma channels:

WhateverSource()
MergeChroma(last, McTemporalDenoise(settings="very high")

That will leave all the luma noise but remove a lot of chroma noise. MergeChroma() merges the luma from the first clip and the chroma from the second.

[Cherbette]

What recommendations would you fellas give for uprez from SD to HD (720p)? I've tried Instant HD & Video Enhancer but it seems many others swear by Avisynths methods...

[sanlyn]

What recommendations would you fellas give for uprez from SD to HD (720p)? I've tried Instant HD & Video Enhancer but it seems many others swear by Avisynths methods...

I hear that among the best is InstantHD plugin for Premiere and AfterEffects. An acquaintance has been using it.
http://www.redgiantsoftware.com/products/all/magic-bullet-instant-hd/
If my friend's experience is any guide, upscaling and/or resizing noisy video and damaged VHS makes it look worse. InstantHD has some builtin filters, but you won't like them. Many people use these plugins, but there's a reason why they do a prep cleanup with AviSynth/VirtualDub beforehand.

BTW, NeatVideo has a Premiere/AfterEffects plugin, as well as for VirtualDub. Like most products that perform beyond the norm, there's a learning curve. http://www.neatvideo.com/

None of this stuff makes AviSynth or VirtualDub any less useful. Archiving and restoring VHS requires many tools. Otherwise, you might just as well keep playing the tapes as-is.

[Cherbette]

None of this stuff makes AviSynth or VirtualDub any less useful. Archiving and restoring VHS requires many tools. Otherwise, you might just as well keep playing the tapes as-is.

I agree with you. I've attempted to archive my tapes several times but have never been satisfied enough with my transfer to trash my tapes. I have so many of them and they take up space. I decided that this time around it would be smart to get some education on the matter

I guess with any upres'ing software you shouldn't expect a miracle especially if your source is VHS. If I'm going to do it for playback on my HDTV, I'd like to do it in the best possible way. You're saying that if I upres VHS it is smart to filter first then upscale or avoid doing so all together?

[Cherbette]

Btw...I'm checking out NeatVideo too. Thanks for that tip

[themaster1]

What recommendations would you fellas give for uprez from SD to HD (720p)? I've tried Instant HD & Video Enhancer but it seems many others swear by Avisynths methods...

Video enhancer is slow but can improve really well your footage, problem is it work in rgb and you're obliged to make a big avi (huff). Avisynth avoid this step as many encoders support avisynth directly.

Filters i use for 720p (in the order)

levels (Ylevels filter)
color correction (HSi (vdub, rgb) and color yuv
gradation curves (vudb, rgb)
color matrix change (colormatrix)
denoise (fft3d or NeatVideo sometimes)
deinterlace (QTGMC)
spline36resize

[sanlyn]

Good info, themaster1. I'd add that the kind of fine-tune color grading sometimes needed with bad VHS has to be done in RGB. A clean VHS likely won't need much color work. The OP noted they have Premiere Pro - great for color, but like most high-end apps of its type it works in RGB. Still, sometimes a tape looks so bad that many initial corrections work only in YUV. With some godawful tapes I've had to do it both ways. But avoid switching back and forth: do as much as possible in YUV, go to RGB later. Every tape has its own problems.

I guess with any upres'ing software you shouldn't expect a miracle especially if your source is VHS. If I'm going to do it for playback on my HDTV, I'd like to do it in the best possible way. You're saying that if I upres VHS it is smart to filter first then upscale or avoid doing so all together?

VHS always requires cleanup of some kind. Even a "clean" tape has residual tape noise that looks worse with upscalers, even those with built-in filters. Most upscalers also sharpen, but they sharpen noise too. Friends who've used upscalers find that upscaler denoisers aren't that great unless you have a pristine source to start with. Much of VHS is aged, faded, off-color, damaged or distorted in some way.

NeatVideo's a great product (if it's good enough for pros with Premiere and FinalCut, it's good enough for me), but you can do good work with MCTemporalDenoise too. MCT is a hassle to load. I'm thinking of assembling its parts and docs into a ZIP file for upload to the forum. I sent your 185-MB video thru both filters - the results look alike to me. Caution: these filters have powerful default settings that can ruin video and make it look like something made from Jello. Read the docs and fiddle around at first. Moderate to light settings work well most of the time.

Ed: I've seen posts here and doom9 speculating that the color noise in your 185-MB video (drifting magenta or cyan color casts going in and out, occasional color "flashes") look like Macrovision after effects. I have copy protected tapes with similar, milder problems after removing copy protection with a TBC. On normal TV playback you'll see some of those effects, along with audio background noise (use headphones and you'll probably hear it). They usually dissipate after the first 30 minutes or so of tape.

Adobe Premiere Pro has histogram, curves, and levels controls like those in Photoshop Pro (similar plugins for VirtualDub, too). You can go to Photoshop sites on the 'net to learn to use them. Here's one on levels and histograms (http://www.cambridgeincolour.com/tutorials/levels.htm) and one on curves (http://www.cambridgeincolour.com/tutorials/photoshop-curves.htm)

I know, it all seems daunting at first . . .

[Cherbette]

I still haven't gotten to it in storage but I'm pretty sure my DVD-R is a DMR-E55K model.

[sanlyn]

All the DMR-E's have built-in TBC that can be used as pass-thru. Use input Line 1.

[Cherbette]

And you said to use the S-video out, correct? Will the S-video out on the DVD-R connect directly to the S-video input on my DC500 or will I need a cord of some kind?

[vhelp]

it will connect.

[vhelp]

looking at your sample above, does your vcr have a setup screen ?

can you post them here so we can see what your vcr is providing ?

your sample looks plasticky, seems the vcr is set to SOFT. if so, see if you can set it to EDIT. that is best setting to use, it retains all the detail, including the noise induced or otherwise. better to capture it as such and then deal with it later through post editing for cleansing. personally, i leave them in and encode to a high bitrate, either xvid or else h264 for viewing on my pc. i made a few test encodes this way with your clips. i much prefered the results from without filtering. but that is just my preference.

but if you plan on playing through a device or dvd player, then you are limited by their required standards for play, those, you will have to apply some filtering out of the noise and in most cases removes the aesthetics feel of vhs. that's why i prefer the above mention.

i'm not familiar with the ES series, but know that they help remove the jitters/wiggeling (timebase errors) but in one of the hauppauge cards has this same feature in the ES series but at cheaper cost. if you dmr-e55k offers this, then great, you are in business for better captures.

[Cherbette]

I'll have to see if I can find the remote to the VCR to get to the setup screen. I've moved so many times over the last few years it's seemingly impossible to find anything or keep it in one place If not, I may try and program my Comcast remote to operate my VCR...I think it will be able to get me to the setup screen

[Cherbette]

Ok here are a couple of grabs:

[sanlyn]

looking at your sample above, does your vcr have a setup screen ?

can you post them here so we can see what your vcr is providing ?

your sample looks plasticky, seems the vcr is set to SOFT. if so, see if you can set it to EDIT. that is best setting to use, it retains all the detail, including the noise induced or otherwise.

vhelp, if you refer to the image in post #69: jagabo determined earlier that the image is from a 3rd-generation tape copy. The only VCR's I know with an "EDIT" mode are some JVC's and older SONYs. A JVC machine In non-EDIT mode wouldn't reproduce noise as sharp as it appears in the sample image.

cherbette, I don't think your VCR has an EDIT mode. Just as well, JVC isn't the only player around and some tapes (especially slow-speed VHS) refuse to look good on them. Slow-speed VHS looks better on SONY or Panasonic -- generally, anyway. But with VHS, there are always exceptions. I had a JVC "7600" for years that served me well while it lived.

I don't know why many people worked with stretched-out images. I prefer the display size, not the rendered size. Note that display aspect ratios and pixel aspect ratios will differ for different media and formats. You'll also find that you retain more of the original 4:3 image if your DVD frame is 704x480 rather than 720x480.

[Cherbette]

So I should capture at 704X480? I've questioned this myself...is there size which will retain the entire 4:3 image?

[sanlyn]

So I should capture at 704X480? I've questioned this myself...is there size which will retain the entire 4:3 image?

How you work with noise/color/edit is often personal preference. I find it difficult to judge noise, skin tones, shadows, etc., if the working image is distorted or pixels are stretched or shrunken. Using the actual display size has two advantages: for internet use, you won't have to do any resize/fitting, because internet/computer display doesn't require DVD or BD dimensions (within limitations, of course). For DVD the rendered aspect ratio and pixel aspect ratio that most closely corresponds to 4:3 is 704x480. The less-than-handful of pixels missing from the top and left are seldom noticed, and are usually noise anyway. Many people cover the tape noise at top or bottom with black (actually RGB 8 or so) borders. VHS outputs 640x480; if you capture at any other frame size, you're resizing.

When digital video was being standardized, 720x480 was for several wide screen movie standards, centered around 16:9 and Panavision, but had to accept wider stuff like CinemaScope. 704x480 was for narrower frames used by Hollywood and Europe. Half-size (352x480) was for lower-res utility and for 16mm and silent-era frames. Anyway, you'd be surprised by what Hollywood does to fit film onto disc: they often add borders or just let pixels go. I'm told that White Christmas (1954), shot in VistaVision, looks slightly stretched on 720x480 DVD, according to people familiar with the original. You'll see some movies that don't quite fill the whole 16:9 screen. Digital video sticks with number systems based on 8, 4, 2 -- Hollywood didn't always think of that. I've removed a bad pixel or two in projects and replaced them with black borders.

Cropping is one thing, resizing is another. Veeerrry difficult and touchy to resize VHS to any extent. Upsizing is far more destructive than reducing a little. You're working with low-rez source to begin with. With YUV, crop or resize only with frame sizes divisible by 8 or 4 (I'd even stick with 2 for YV12). RGB usually can work work with uneven numbers. At the render-to-DVD stage, you have to stick with even numbers.

[jagabo]

Analog video capture cards are usually based on the BT.601 spec. The 4:3 frame is contained in a 704x480 frame. If the card captures 720x480 it is capturing a little more than the 4:3 image width -- the inner 704x480 still contains the 4:3 image, there's just a little padding at the left and right edges (in case the capture isn't perfectly centered). Ie, the full 720x480 frame represents a 1.818... AR picture, not a 1.777... AR picture.

The MPEG 2 specification* (which the DVD spec refers to regarding aspect ratios) states the entire frame represents the aspect ratio. For a 704x480 frame that matches the BT.601 spec. But it's at odds with the common practice of capturing a 720x480 frame and the use of a 720x480 frame on DVDs. How DVD players handle this varies from player to player, even for the different outputs on the same player. For example, my player follows the BT.601 spec for the composite output, but the MPEG 2 spec for upscaled HDMI output. Professionally authored DVDs are almost always 720x480 (though 704x480 is supported) and usually seem to ignore the difference between the two specs. In any case, the difference is very small, only about 2 percent.


* In the MPEG 2 spec the AR is represented by a 4 bit number (16 possible different values):

0) forbidden
1) square pixel (DAR = frame size ratio)
2) 4:3
3) 16:9
4) 2.21:1
5-15) reserved

Of those, only 4:3 and 16:9 are supported by the DVD spec.

[sanlyn]

Precise clarification, jagabo. I read similar material many times over (it can drive you to drink -- or worse -- after a while). My experience with 4:3 tapes has me watching opening titles after they're rendered to DVD. The titles are shifted leftward with 720x480, are more centered with 704X480. It just might be my various components are in or out of spec, I don't know. I found that VCR capture at either 640x480 or 704x480, with either rendered at 704x480 DVD, had titles centered and took less from borders.

Hmm. Need time to to test that and compare (time? What's time?). I got the 704x480 idea from a post by lordsmurf some years back. Need time to find that post (Time?...). You're right, there's likely very little dfifference. I prefer working with the way video will be displayed, not rendered. Some prefer otherwise.

[jagabo]

Like I said, individual devices handle the frame sizes differently.

[Cherbette]

Just went and got my DVD-R out of storage and the S-video IN on my VC500 won't connect directly to the S-video OUT on my DVD-R and I don't have a cord nor the finances to get one at this point