digitalFAQ.com Forum

digitalFAQ.com Forum (https://www.digitalfaq.com/forum/)
-   Capture, Record, Transfer (https://www.digitalfaq.com/forum/video-capture/)
-   -   Com World CMD-1200 has TBC? (https://www.digitalfaq.com/forum/video-capture/12289-world-cmd-1200-a.html)

BarryTheCrab 11-13-2021 10:29 AM

Com World CMD-1200 has TBC?
 
2 Attachment(s)
At the risk of being pummeled without mercy...I post this!
I paid $9 for a CMD-1200 signal standards converter, because it claimed to have a TBC.
So for the pittance, I jumped.
Attached are a sample (Direct Stream Copy) of the same general frames with and without the CMD-1200.
Details, such as they are...Mitsu 778, and my precious Tevion, Windows 7.
ZERO processing, just NTSC in and NTSC out.
Comments are welcome, I'll don my helmet.

lordsmurf 11-13-2021 10:42 AM

Where'd you get it? :hmm:

BarryTheCrab 11-13-2021 10:46 AM

You're gonna kill me...Goodwill, the online site.

lordsmurf 11-13-2021 11:25 AM

I can never get that site to work properly. :(

I can't look at your clips here, but I do know about that model. It can be good as a TBC. These are old, rare. I'll have to look at your samples later. You may have scored in a major way.

msgohan 11-13-2021 12:52 PM

2 Attachment(s)
The clips are better suited to a line TBC test. They won't tell us anything about its frame TBC performance. It's straightening lines better than your direct Tevion capture, especially at the top of the frame, but it's still a poor result compared to what a DMR-ES15 etc. would do. That black border on the left should be completely straight. And this appears to be the least-challenging source material (retail Hollywood movie).

Comparing individual fields:
Attachment 14333
Attachment 14334

One frame TBC test might be a recording that includes a lot of stops, starts, unrecorded portions, etc. Here is my extreme example...
Quote:

Originally Posted by myself
This is from a summer animation program I took part in as a kid. As I recall, the machine could somehow be set to record 1, 2, 3, etc. individual frames at a time to VHS. This constant start/stop would be a chaotic signal even if this was the 1st-gen recording. I believe what we were given is 3rd-gen.

I didn't think YouTube would handle this comparison quite so poorly.



Scripts:
Code:

AVISource("Test_Mitsu_no CM1200-DSC.avi")

ColorYUV(off_y=-12)

AssumeTFF().SeparateFields()

Code:

AVISource("Test_Mitsu_with CM1200-DSC.avi")

ConvertToYV24().Crop(5,0,-0,-2).AddBorders(0,2,5,0,color=color_white)

AssumeTFF().SeparateFields()


BarryTheCrab 11-13-2021 10:07 PM

MSGOHAN,
thank you for your interest in the topic, and the script you posted.
Truth be told, I have never scripted anything in my life, all my coding is channeled through the UI of Hybrid and VirtualDub, I never see it.
However...your code is so brief, maybe I could actually utilize it in my first ME-code!
Just to enlighten you on my ignurince...
What does the first code do to the "no" video, and, following along the same vein...what the heck does it do for the "with" video? Particularly separate fields, is that to fix the frame rate film to VHS/TV stuutter?

msgohan 11-14-2021 02:40 AM

3 Attachment(s)
Common to both scripts

AssumeTFF().SeparateFields()
  • The first part sets "Top Field First". I can't give a simple explanation for why this is needed, so let's ignore it and I'll try to explain the second part.
  • SeparateFields takes two fields "woven" together and instead displays them as two separate frames each containing only one field. Your 29.97 fps 720x480 capture becomes a 59.94 fps 720x240 video. I find this view useful for analysis, as it's closer to a native representation of NTSC video. It shouldn't be used for a final output.
You can force VDub's Deinterlace filter to work the same as SeparateFields with the settings below, if you want to get a better idea by playing around yourself. For me, this only works in VirtualDub2; my classic VirtualDub version crashes.
Attachment 14338

Everything else in the scripts is just there to make comparison easier: roughly match brightness, and match spatial alignment as closely as possible. If you flick between my two screenshots in separate browser tabs (or download them and arrow back and forth in an image viewer) they don't jump around the way that screenshots direct from the clips would.

Animated GIFs showing what I mean, before scripts vs after scripts:
Attachment 14339
Attachment 14340

"No CM1200" script

ColorYUV(off_y=-12)
  • Lowers the brightness by simply shifting all Y (luma) values down by 12. A pixel with a brightness level of 12 becomes 0, etc.
"With CM1200" script

ConvertToYV24().Crop(5,0,-0,-2).AddBorders(0,2,5,0,color=color_white)
  • Shifts image left by 5 pixels and down by 2 pixels. First it's cropped, then it's shifted down and padded to maintain its dimensions. The Convert command is only there because the format that we capture in can't be cropped horizontally by odd numbers.

lordsmurf 11-14-2021 03:55 AM

We PM'd, and I know this model unit. I have one myself.

But it has caveats, namely the potential to have flawed chipsets like other Cypress. There are also no-TBC versions. Remember, this was a converter, not TBC. There are variants, many of them not good.

ComWorld is the rebadge brand (a rebadger of misc PAL<>NTSC items), not the maker. For $9, a no-brainer, but for a more typical TBC cost, you should give pause before plopping down the credit card. There's also potential for an earlier generation variation, that lacked the TBCs, those exist as well.

The line TBC correction of this model, when any TBC actually present, is weak and flawed, so not worth further discussion, at least not in any practical sense. (In a research sense, yes. That is somewhat unique in the world of TBCs, but never seems to check both boxes in terms of line+frame both working correctly and concurrently.) Since it does have obvious line, it likely has frame as well, not a prequel model. More often than not, the line performance makes the overall signal worse, not better.

I've not yet had time to get the info I need, to confirm the frame TBC quality. The JVC menu test is a quick cheat, though not the only test.

It does have quite decent luma values.

BarryTheCrab 11-14-2021 06:32 AM

I do not dare open this thing up, but it was brand new in-the-box, SN WT05B 2807.
Later I will try a JVC menu, I'll have to use my 3500 because the 7800 is going to the shop (John's TV, LLC, Taunton, MA)
I intend to pair the CMD with the ES-10 or 15, to see if they complement each other.
Thing is I need to find a better tape to post, Goodfellas has so much foul mouth murderous fun it's hard to find a clean clip, Blazing Saddles, another one that hilariously offends everyone almost every minute.
Maybe a home tape, VHS or Video8, with no filtering. I'll find another sample.

-- merged --

LordSmurf and all,
I have not yet made a new capture worthy of posting but my preliminary attempts re: JVC menu show no freeze no stutter no nuthin’.

-- merged --

Uhgg, damn unit suddenly decided to no longer deliver an image, neither S-video nor composite.
Tried different cables, of/on/off/on, a little wiggle, etc.
I'm so disappointed.
It powers on and acts normal, just nothing visual happening.
Well, it was fun while it lasted. I'll keep messing with it but I ain't hopeful.

EDIT: It is essential you plug the unit into the VCR you are actually using!!! D'oh!

latreche34 02-05-2022 01:33 PM

From the sample you posted it does have some line TBC'ish functionality judging by the line delay and better vertical lines, but it is nowhere near a built in VCR line TBC, the frame TBC function remains to be seen.

BarryTheCrab 02-05-2022 03:58 PM

It certainly improves the capture, and I'm happy to have it, especially for the price point.
So, to offer up a proper sample, what would you suggest?
I have a Sony TRV-15, my first video camera! No S-video but plenty of old footage, or I can shoot new.
I also have a Sony DCR TRV-530, S-video, I can shoot new video or use old videotapes if they play.
And a Canon HV-30, I can shoot new or grab some other tape, but that's probably not what you are after.
Let me know and I'll try to accommodate.
I will capture HuffYUV, 720x480, using either my refurbed 7800 or refurbed 4800.
Windows 7, Tevion DVD Maker.
And what would you want for the capture settings on the machines, only the 7800 has TBC.

lordsmurf 02-06-2022 02:30 PM

So it isn't failed after all? That's good. :)

I get so tired of samples that are crap homeshot footage, shaky, under/overexposed, etc. If you want to show a sample, at very least, it needs to be stable with relatively good exposure/color values. I tend to like homemade cartoon tapes to show errors, as the animation often reveals errors more obviously. But I know others lack the animation collection I have, so do the best you can.

BarryTheCrab 02-08-2022 05:55 AM

3 Attachment(s)
Here are 3 sample files...
Shot with bare bones TRV-15
Played on a TRV-530 out via s-video

I was considering using MPEG2 files to get longer uploads, a better feel for the video, as I'm not really using this for restoration rather a demonstration. I can redo if MPEG2 is a better choice.

lordsmurf 02-08-2022 02:32 PM

MPEG-2 is fine, 4:2:2, interlaced. Or H.264, again 4:2:2, interlaced.
What matter with either is good bitrates.

BarryTheCrab 02-09-2022 05:28 AM

First let me say the files I uploaded were all supposed to be HuffYuv but I think my VDub1 kept diverting Stream Copy to the HuffYuv library when I wasn't looking. Only one is HuffYuv but I do not know if that matters.
Next...I haven't found a way to capture/create an MPEG2 4:2:2. Nor have I found a path to a 4:2:2 interlaced MP4 or any interlaced MP4 to be honest.
Will MagicYuv be OK? It seems to deliver a more lengthy video for the 99mb we are allowed, if only 10 seconds.
Sorry to drag this out, I'm not sure anyone even gives a hoot.

lordsmurf 02-09-2022 07:23 AM

4:2:2 MPEG-2 is a problem with freeware.

But Hybrid has no issues making 4:2:2 H.264 files, one of my custom presets even does it.

BarryTheCrab 02-10-2022 07:15 PM

3 Attachment(s)
OK, heeeere we try again!
I think I figured it out. Now that I have half a clue I'll do this again with a different tape if this is unworthy.


All times are GMT -5. The time now is 11:19 AM

Site design, images and content © 2002-2024 The Digital FAQ, www.digitalFAQ.com
Forum Software by vBulletin · Copyright © 2024 Jelsoft Enterprises Ltd.