VHS capturing: what do I need to own and know?

[lordsmurf]

Quote:

Originally Posted by koberulz

Anyone know anything about this? More expensive than the AVT-8710, but I got mine and it's faulty, which seems to be happening a lot. And it's still cheaper than a TBC-5000, and has the proc amp controls.

The TVOne and AVToolbox TBCs are using the same chips. The 8710 and 1T-TBC both have issues, as do all Cypress products. TVOne and AVT are actually just Cypress rebadges from Taiwan.

I've not listed them in the marketplace yet, but I have
- DataVideo TBC-100 PCI card (rare!), new in original box, for $485
- AVT-8710 green version, tested and known to work flawlessly, new in original box, for $300

[koberulz]

Quote:

Originally Posted by lordsmurf

The TVOne and AVToolbox TBCs are using the same chips. The 8710 and 1T-TBC both have issues, as do all Cypress products. TVOne and AVT are actually just Cypress rebadges from Taiwan.

I've not listed them in the marketplace yet, but I have
- DataVideo TBC-100 PCI card (rare!), new in original box, for $485
- AVT-8710 green version, tested and known to work flawlessly, new in original box, for $300

US dollars? I'd be happy to take the AVT at that price, rather than keep gambling with B&H. Still has the different power connectors for different countries?

[lordsmurf]

USD, yes. And I'll need to calculate shipping. PM me your address.

[koberulz]

Done. Just got confirmation I've successfully canceled my reorder, too.

[koberulz]

Well, finally managed to get my hands on all the equipment, so: capturing samples.

Original is just the video as-is. ProcAmp used the ProcAmp settings for the USB-Live2 to try and get the blacks more black. Not sure whether it's better to do it that way or do it in VirtualDub or AviSynth later?

[lordsmurf]

The color is really off, mostly due to the chroma offset and blooming hue. But it's fixable.
I'm on the wrong computer right now, so can't do anything right now.

[koberulz]

Yeah, I'm planning on running it through VDub/AviSynth. Just want to get the capturing process right first. This tape was actually chosen specifically because it looks awful.

[sanlyn]

Quote:

Originally Posted by koberulz

Yeah, I'm planning on running it through VDub/AviSynth. Just want to get the capturing process right first. This tape was actually chosen specifically because it looks awful.

Yeah, rather awful, but I've hassled with some of them myself, and worse.

You're on the right track. But note that by not cropping borders with Virtualdub capture's Crop window the black borders are throwing off your histograms. I made some frame caps to illustrate this (the pics are slightly reduced in size to keep from stretching the panel display too wide).

Below is a cap of Original.avi frame 44 with the borders intact and a YUV histogram at the right. Most of the dark data in the upper white luma band shows that usable darki data is up around RGB 60. No hard clipping there, just a smooth rolloff which is what you want. The frame does have a lot of darks surrounding the bright arena so you can expect the histogram to have a little mountain in the dark area. At the far left of the histogram you can see smaller, separate peaks that represent the black borders. Brights are slightly into the unsafe area, but that can be recovered later.


Using the capture app's Crop dialog and removing borders from the input, you can see that the histogram shows elevated blacks. That's not a disaster -- at least darks aren't hard clipped and unrecoverable.


Considering the original tape doesn't have much sharp detail in the dark grandstands (VHS has really crummy shadow rendering, even with a better original), you could allow that left hand end of data rolloff lie closer to the left side and avoid some work. Even at that, you'd still have tweak the darks later to get what you can out of them. The temptation is to try to make natural darks look fully lighteded, which doesn't work.

Below, a frame from ProcAmp.avi, which has almost an identical YUV histogram but at least the blacks are a little blacker, if still elevated. I adjusted levels in YUV (Avisynth) and tweaked a little more in VirtualDub with a very slight gradation curve hump at about RGB 40, and brought darker stuff down to RGB 16, since there's nothing down there anyway and it's noisy. Earlier in YUV I also reduced red saturation, which caused an unnatural red glow in the original.

In Avisynth YUY2 the borders were cropped, then AddBorders added black pixels to the edges, centering the image, and resulting a 704x576 frame. That frame size is perfectly acceptable for 4:3 video, but you can leave an extra 8 pixels in place on each side for 720x576. If you had not raised darks beforehand, you'd have hard clipping and zero detail in the dark grandstand. My adjustments were quickies -- you can adjust to suit your purpose. (Note that images like this show up brighter in media players and TV than in web browsers.)


The code I used to fix up those borders for a 704x576 frame with no image resizing):

Crop(8,12,-28,-10).AddBorders(10,12,10,10)

For a 720x576 frame, just keep the extra pixels on the sides:

Crop(8,12,-28,-10).AddBorders(18,12,18,10)

Be careful, though: if the video is 16:9 DAR, use 720x576. This was done in YUY2. It won't work properly in YV12 with interlaced video which requires that cropping height must be done in groups of 4 pixels. Look at the table of allowed values near the bottom of this page: http://avisynth.nl/index.php/Crop.

[koberulz]

Yeah, I just threw this together really quickly in VirtualDub:


Didn't know the thing about cropping restrictions, so I just went with what looked good (6 & 28 X, 12 & 10 Y). Not sure how much that'll affect it, or what colour format it's actually in.

It's PAL, not NTSC, too, so it should end up at 576 pixels high.

Not sure what happened with the whites? I had an AVS set up just to load it (via GraphEdit, before capturing) and add a Histogram over the top, and checked through a bit of the tape and all the whites were in the safe zone.

Levels adjustments were made in VirtualDub using the ColorTools Wave Form Monitor, so between that and the AviSynth Histogram (which is also a wave form monitor, in reality) the borders were fairly easy to identify and ignore for the purposes of adjustments.

My previous experience watching that footage was from a simple DVD-recorder capture, over which even my quick adjustments are a massive improvement:


Which does make it a bit hard to see any flaws there might be in what I've done, because it's definitely a lot closer to where it should be than the previous version.

[sanlyn]

Quote:

Originally Posted by koberulz

It's PAL, not NTSC, too, so it should end up at 576 pixels high.

Yep. Corrected that while you were reading the post.

[koberulz]

Well, I see how I missed that unsafe white:
WhiteSafe.png

It's more of a problem elsewhere in the video, though:

You must be logged in to view this content; either login or register for the forum. The attached screen shots, before/after images, photos and graphics are created/posted for the benefit of site members. And you are invited to join our digital media community.

There's a standard video introduction, which is completely different in terms of quality to the actual game, thus that happening. How do I get those whites down?

[sanlyn]

Quote:

Originally Posted by koberulz

There's a standard video introduction, which is completely different in terms of quality to the actual game, thus that happening. How do I get those whites down?

As you've seen, "Bright" or brightness controls black level. Contrast controls white level. The two controls interact somewhat. Contrast adjusts white levels mostly but has some visible effect on black levels. The converse is true: brightness adjusts black levels mostly but has a slight effect on brights. Thus, lowering contrast lowers brights but affects the lower end somewhat, so you have to jockey back and forth to make everything fit. But it's not as difficult as it sounds. You get the hang of it quickly.

The same action holds true for most editor brighgtness/contrast controls. Unless you're working with specialized filters that let you enable automatic compensation during certain adjustments (such as ColorFinesse and a few others), you tweak black and bright adjustments together manually.

YUV luminance is expanded at both ends when converted to RGB. Thus, if you have blacks at Y=16 in YUV, when converted to RGB the blacks will be closer to RGB=0. Brights are expanded as well. So if you have the bright end overflowing the safe zone to any great extent in YUV, much of it will be clipped in RGB. Once RGB clips out-of-spec YUV values, it's too late to retrieve clipped detail. This is why most users check the YUV spectrum first in something like Avisynth before opening a video directly in editors that work in RGB. Some advanced NLE's like Vegas Pro, Premiere Pro, After Effects, and even the color filters in TMPGEnc Mastering Works, allow working in YUV as well as RGB.

[koberulz]

Yeah, I had it figured out with the AVT/internal proc amp controls. Just not sure what the best method is in VDub? I can use Levels to make whites whiter and blacks blacker, just not sure how to do the opposite.

Spent a bit of time with it, came up with this:
https://dl.dropboxusercontent.com/u/...ginal_game.avi
https://dl.dropboxusercontent.com/u/...tored_game.avi

Dropbox links because it exceeds the attachment size. Thoughts? I've basically just been following this.

[sanlyn]

Both of your links give 404 errors (page not found)

The VDub Levels filter acts like similar controls in many NLE's. Be careful with raising brights, it can blow out highlights and upper midtones if you're not careful. Vdub has a builtin Contrast/Brightness controls, but like all such controls it's limited and is usually not used. There are better filters with more specific adjustments.

Attached are 4 VirtualDub filters, 2 for levels/colors, 1 for hue/saturation/intensity, 1 for denoising. Docs included. All have been posted earlier .

[EDIT] I just noticed that the webiste of the author of ColorMill has taken to showing popup ads to help pay for his work. That's a shame. Attached is a folder with an offline copy of the website and graphics. It's the web page only, no ads. It opened correctly in Firefox and IE8.

[koberulz]

The restoration is still uploading to Dropbox. The same was probably true of the original when you tried it, thus the error. Somehow I forgot to think about that. 14 minutes remaining on the restoration as of posting this.

As I said earlier, I've been using the ColorTools Wave Form Monitor to make my levels adjustments (EDIT: and haven't touched the brights, as it's obviously not necessary with how bright this footage is to begin with). I've also used the hue/sat/int plugin you linked to. I do have the other three plugins (I downloaded the lordsmurf VirtualDub in the stickied thread), but haven't used them as yet. I think I opened Color Mill and promptly got lost.

[sanlyn]

Quote:

Originally Posted by koberulz

I think I opened Color Mill and promptly got lost.

All you do with ColorMill is click on a category, move sliders up and down, and watch the results in its preview. Otherwise, can't help you there.

Quote:

Originally Posted by koberulz

https://dl.dropboxusercontent.com/u/...ginal_game.avi
https://dl.dropboxusercontent.com/u/...tored_game.avi

[koberulz]

Yeah, there's a limit of 20GB or 100,000 downloads a day.

Which I can pretty much guarantee wasn't reached with two 200MB files.

*sigh*

[koberulz]

I'll try again with smaller files I can attach.

[sanlyn]

Downloaded OK, thanks. Better to have samples in the forum anyway than losing them later at download sites.

It's the dinner hour here in North Carolina, so I must stop now and feed the wife. Will look over the samples tonight. Thank you for your efforts.

[koberulz]

Quote:

Originally Posted by sanlyn

All you do with ColorMill is click on a category, move sliders up and down, and watch the results in its preview. Otherwise, can't help you there.

Having reopened it, I guess it's just an initially overwhelming number of options. Apart from that, though, not sure what the 'stick' and 'lock' buttons do.