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  #61  
08-18-2019, 03:46 AM
dima dima is offline
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I captured the image directly from the source (via VirtulDub) and it is 720 x 576 (1.25:1; it was also captured), and not like the playback program it showed in 768 x 576 (1.33:1).
------------------------------------------------------
I read about image formats (not from today)... But I still may not know much about it.
768 x 576(1,33:1) is OAR and 720 x 576 (1.25:1) for VHS tapes... is a non-original, distorted image (image format) compared to the original(for PAL) ?

"Capture the spec res. You can convert it to whatever else is needed post-capture. Noting that 768x576 is wholly useless, the 4x3 is 720x540, and deinterlaced. I guess, technically, 768x576 would retain interlace, but no interlaced (player) device will view it, not a valid res. The source does not contain 768 detail, nor even 720."

Source quote: http://www.digitalfaq.com/forum/vide...html#post63434

Most player(devices) will not display interlaced video in 768 x 576 ? At 720 x 576, yes ?

Last edited by dima; 08-18-2019 at 03:58 AM.
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  #62  
08-18-2019, 03:54 AM
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The reasoning is because it's the standard, decided on years ago, predating even my own foray into video. It just is. 768 was never a standard, no support, often not even possible.

Realize that I find lots of stuff to be strange, but the reasonings are generally very technical. Sometimes arbitrary. For example, why did head-switching noise need to be visible? It's my understanding that this could have been hidden, but wasn't due to laziness of relying on overscan. In fact, much of the overscan noise could have been removed. I could ask why all day, but ultimately it does not matter. It is what it is. We just work around it, correct in post-capture edit/restore.

So, you capture 720x576, and you later resize to the desired viewing size. The end.

But noting that 768 is probably not a wise choice. Either leave it 720x576 interlaced, or 720x540 deinterlaced/progressive. PAL VHS has zero detail past 300x (give or take, depending on if you worship Kell factor).

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  #63  
08-18-2019, 03:59 AM
dima dima is offline
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I edited my earlier post.

-- merged --

Most player(devices) will not display interlaced video in 768 x 576 ? At 720 x 576, yes ?

-- merged --

Does ATI AIW USB (ATI TV Wonder USB 2.0) have integrated (internal) A/V capture timing ?

I think which of these five settings would be best for this device... An S-VHS VCR with built-in TBC (without external TBC) and a tape that is in good condition, but in literally at most a few places (short-lived - what for a maximum of three seconds, and most often a second or less) may have a broken (completely) or distorted signal - sound and image...

1.
Resync mode:
[x] Sync audio to video

[x] Correct video timing
[x] Automatically disable resync

2.
Resync mode:
[x] Do not resync

[ ] Correct video timing
[ ] Automatically disable resync

3.
Resync mode:
[x] Do not resync

[x] Correct video timing
[ ] Automatically disable resync

4.
Resync mode:
[x] Do not resync

[ ] Correct video timing
[x] Automatically disable resync

5.
Resync mode:
[x] Do not resync

[x] Correct video timing
[x] Automatically disable resync

General options: all two of these are set up in all variants on: OFF.
Audio latency determination: DEFAULT.
DirectShow options: all set up on: OFF.
[I think that these options are fine set in every variant and used equipment and cassette, although I read that Lordsmurf "advised" to leave all options in the tab "Timing" as default so I'm not sure how it is the best. Maybe practise will show this - because every case could be different than other/s.]
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  #64  
08-27-2019, 07:03 AM
sanlyn sanlyn is offline
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Number 2 is recommended for USB devices in the earlier notes posted in this guide, because most USB capture devices perform their own a/v sync internally. That's what I use for my VC500. if you want to experiment with other settings it's up to you.


Quote:
Originally Posted by dima View Post
Does ATI AIW USB (ATI TV Wonder USB 2.0) have integrated (internal) A/V capture timing ?

I think which of these five settings would be best for this device... An S-VHS VCR with built-in TBC (without external TBC) and a tape that is in good condition, but in literally at most a few places (short-lived - what for a maximum of three seconds, and most often a second or less) may have a broken (completely) or distorted signal - sound and image...

1.
Resync mode:
[x] Sync audio to video

[x] Correct video timing
[x] Automatically disable resync

2.
Resync mode:
[x] Do not resync

[ ] Correct video timing
[ ] Automatically disable resync

3.
Resync mode:
[x] Do not resync

[x] Correct video timing
[ ] Automatically disable resync

4.
Resync mode:
[x] Do not resync

[ ] Correct video timing
[x] Automatically disable resync

5.
Resync mode:
[x] Do not resync

[x] Correct video timing
[x] Automatically disable resync

General options: all two of these are set up in all variants on: OFF.
Audio latency determination: DEFAULT.
DirectShow options: all set up on: OFF.
[I think that these options are fine set in every variant and used equipment and cassette, although I read that Lordsmurf "advised" to leave all options in the tab "Timing" as default so I'm not sure how it is the best. Maybe practise will show this - because every case could be different than other/s.]
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  #65  
08-27-2019, 07:16 AM
dima dima is offline
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Thank you.

lordsmurf Can you comment on my question - especially in the context of (thinking) about ATI AIW USB(ATI TV Wonder USB 2.0) ?
I mean especially this my question: Does ATI AIW USB (ATI TV Wonder USB 2.0) have integrated (internal) A/V capture timing ?
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  #66  
08-27-2019, 08:08 AM
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Quote:
Originally Posted by dima View Post
lordsmurf Can you comment on my question - especially in the context of (thinking) about ATI AIW USB(ATI TV Wonder USB 2.0) ?
I mean especially this my question: Does ATI AIW USB (ATI TV Wonder USB 2.0) have integrated (internal) A/V capture timing ?
I'm not sure it matters. I'm more worried about the capture, if it's in sync, not hardware timing. I think you're really overthinking some things.

Let me turn things around here: Why are you asking this question?

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  #67  
08-28-2019, 01:13 AM
dima dima is offline
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Because I would like to know how it is in the context of the best "parameter" setting for capture in VirtualDub.
And I just want to know how this device works on this subject.
So do you know does ATI AIW USB (ATI TV Wonder USB 2.0) have integrated (internal) A/V capture timing ?
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  #68  
08-28-2019, 02:32 AM
sanlyn sanlyn is offline
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USB capture devices tat we recommend have their own internal a/v sync in their processing chips, as far as we know. If you want to conduct your own experiments with non-recommended products you're free to do so. The reason VirtualDub has sync options is to accommodate those devices that do their own sync work. My experience with telling VirtualDub to resync and handle its own inserting/dropping frames is that you'll usually get inserted and dropped frames unless you're using an external frame-level tbc, which you don't want to use. You can expect dirt-cheap Asian copies of recommended devices to use undocumented and unidentifiable components give unpredictable and undesirable results. The settings I entered for USB devices are those that I've used and have seen recommended by others who use the same products. Different system setups can often yield different results with the same device. The capture guide is a guide, not a bible.
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  #69  
08-28-2019, 04:59 AM
dima dima is offline
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Thank you for this information.

Most players(devices) will not display interlaced video in 768 x 576 ? At 720 x 576, yes ?
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  #70  
08-28-2019, 06:13 AM
sanlyn sanlyn is offline
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Your question makes no sense. Do you want 720x576 video to play at 768x576, or do you want 720x576 video encoded to play with a 4:3 display aspect ratio at any frame size on any display device? Does your display device measure exactly 768x576? Is your PC monitor or TV or other display device limited to 768x576? Can you configure your media player to play video at exactly 768x576 on any display? If you have an NTSC video or DVD at 720x480, do you want NTSC to also play at 768x576? Why do you want 768x576 specifically? How are you capturing? What is your final goal for output? Do you want square pixel video or anamorphic video? Do you know the difference? Do you want DVD, BluRay, web mounting, SmartPhone, one or two of these, three of these, or all 4 of these? Has it previously been mentioned in earlier posts from lordsmurf that 768x576 is a nonstandard frame size that would mean trouble for many display devices and encoders?
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  #71  
08-28-2019, 06:55 AM
dima dima is offline
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I would like this image resolution because: I would like the image of "my" movie to be always displayed in the aspect ratio: 1.33:1(4:3) (OAR) on every screen*, not in 1.25:1 (not original image format).

* In a situation when I know that my screen is a 16:9 display and when the aspect ratio is set to: 16:9 (not stretching to 16:9 "narrower" images, only entering them in this aspect ratio: black stripes on the sides screen for 4:3 format). Without using any stretching or narrowing of the aspect ratio - just in the native format of the TV or other devices that it will be displayed in 1.33:1 (4:3).

Can I do it differently without losing quality (if possible) than after capturing the image in 720 x 576 (5:4; 1.25:1) stretch this image to 768 x 576 (4:3; 1.33:1)?
[If the image were captured in 768 x 576, there would probably be no "problem."]
Even if the image quality is "lost". Let's assume that the correct image format is more important than image quality and that someone chooses the correct image format.
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  #72  
08-28-2019, 08:54 AM
sanlyn sanlyn is offline
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Unfortunately you still don't understand that 1.25:1 for 720x576 is the physical aspect ratio of a standard PAL video frame. As a lossless and un-encoded video it plays at 720x576 because un-encoded AVI has no display aspect ratio and always plays at its physical frame size. If you encode using MPEG or h.264 and specify a 4:3 display aspect ratio (DAR), the final 720x576 video video will always play at 4:3 regardless of the size of the display device.

You should also know that every PAL DVD recording that you own or watch in other people's homes has a frame size of 720x576, whether its playback aspect Ratio is 4:3 or 16:9. Some of the PAL DVD's might play at 4:3 or in CinemaScope or Panavision, but the frame size on those PAL DVD's is 720x576. If you own any NTSC DVD's, the frame size on those NTSC DVD's is 720x480, which is a 2:3 aspect ratio frame, but they can play 4:3, VistaVision, Panasvision, or CinemaScope frames st the proper aspect ratio because of the way they are encoded. You can get the same results when you encode your 720x576 AVI's, but you simply don't understand it and explaining the same thing again and again is getting tiresome. Unfortunately, if you transfer a PAL DVD to your computer for editing, the VOB files will play at 4:3 in a media player but in an editor they will display as 720x576. (1.25:1).

Capture to lossless 640x480, which is an industry standard 4:3 square pixel frame size. Don't use an oddball frame size like 768x576 -- it's asking for trouble. 640x480 will always display at 4:3 on any display device and when it's encoded it will still display at 4:3 unless you specify another display aspect ratio. Note that 640x480 cannot be used for DVD or for standard definition BluRay, both of which require 720x576 for PAL or 720x480 for NTSC. 640x480 will play on most DVD or BluRay players when encoded with MPEG, but a BluRay player is required for playing h.264 encodes. A modern SmartTV can display either of those encodes if you encode it according to the requirements of the TV -- and remember that smart TV's are not computers and can often be very stupid when it comes to different formats.
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  #73  
08-28-2019, 09:14 AM
dima dima is offline
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Quote:
Originally Posted by sanlyn View Post
No display
disables overlay and preview displays.

Overlay
With most capture devices, "overlay" directs the device to feed the video stream directly into the video card's display memory rather than let VirtualDub control the image display. This works with some cards, but with others only "Preview" works. Also depends on whether you've set a capture frame size that isn't like the incoming frame proportions. For example, if the capture device outputs 4:3 but you want capture at 720x480, the overlay panel will freeze or crash. I use Preview mode and let VirtualDub control display.

Preview
Displays video using the frame size you've set for capture. With some cards fast motion can stutter a bit depending on the device, the display driver itself, or other system factors. Ordinarily this doesn't mean that the capture itself stutters. Display stutter tends to mitigate if Audio Preview is turned off or when capture starts. It's annoying at times, but according to comments from others the captured signal has already passed through several stages, so preview doesn't always reflect the actual state of the capture itself. I see occasional stutter on one PC but not on two others. One user stated that increasing disc I/O cache improves preview speed (See part 5 later: Capture top menu/Disk I/O), but I've never tried it
Quote:
Originally Posted by lordsmurf View Post
(3) Overlay is best. In this display mode the video does not eat into CPU/RAM, thus prevent issues with timing/cache/etc. Again, when you have one issue, you almost always have multiple issues. The workaround is preview mode, which can cause conflicts with timing/cache/etc. So all settings must be tweaked. This is the main reason my ideal setting do not match sanlyn's. Apparently his main system, like my own secondary/backup system, has mild but workable capture problems.
It is a pity in my opinion that by setting "No display" you cannot change this while capturing.
From what I checked, this option consumes probably the least CPU and RAM, probably also among all three display options to choose from. As for Preview and Overlay, CPU usage looks very similar (I don't know what RAM is like).

1. Suppose I use: Overlay or Preview. Is it best for capture (among other things, probably CPU consumption, etc., but not only) to minimize the capture window and the entire VirtulDub or leave it open on the screen ?

2. Is the best for capturing (among other things probably about CPU consumption, etc., but not only) is to set the computer screen blanking or is it better to keep it awake (though I can't remember, but I don't know if sometimes when capturing the screen despite settings from the capture will not expire) ?

Another good option replacing the inability to turn off "No display" during capture may be connecting the VCR to a second computer via any other converter via e.g. SCART or Composite and observing the image there, cassette end etc.
3. Using a VCR at the same time on two devices can cause some problems with the VCR so that e.g. the proper signal (which is captured via S-Video) can be weakened, distorted or completely not delivered at some point in time if it could not be delivered using it on two devices (connections) ?
4. Does using it on two devices during cassette playback and capture cause any problems for the signal ?
5. Perhaps because it is an analog signal: there may be interference from additional devices, cables, transmission nearby... Yes ?

Quote:
Originally Posted by sanlyn View Post
Unfortunately you still don't understand
Thank you for the explanation.

Can you say something about this: http://www.digitalfaq.com/forum/vide...html#post63712 ?
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  #74  
08-28-2019, 03:02 PM
sanlyn sanlyn is offline
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Lordsmurf likes overlay mode, for whatever reason. I prefer the more efficient preview mode, for reasons stated in the quoted material. Also, the capture histogram won't work in overlay mode. Use the mode you prefer or the mode that gives less trouble.

Why anyone wants to capture without seeing what's happening is a mystery to me. But everyone is different.
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  #75  
01-14-2020, 10:32 AM
Okiba Okiba is offline
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Thanks for the detailed guide! This helps a lot for non-technical people. I'm assuming this is still correct, as people were recently submitting question. I have couple of questions:

Quote:
With most capture devices, "overlay" directs the device to feed the video stream directly into the video card's display memory rather than let VirtualDub control the image display.
Wouldn't that always be a good idea to use Preview so you can tweak your white/blacks with histogram? - but anyhow - no matter which I choose Preview or Overlay, shuttering or not shuttering - this does not effect capture?

Quote:
- - "Output size" can be changed here but I do it in "Custom format" and keep it all in one place. The setting in "Custom format..." will be reflected here.
My default resolution is not 720x570. When I tried to set it, it says the resolution is not supported by the Capture device. I'm using the VC500. Why is that?

Quote:
- - "Video standard" of the input source.
NTSC didn't work for me. I'm assuming that because I'm not from the US. PAL did work. Actually, couple of PAL variants worked for me. PAL G, PAL B, etc. Is there is differences between the PAL options? or as long as I can see the the record on the overlay/preview I'm fine as all I checked had the same FPS?

Quote:
Below, my setup for Huffyuv lossless compression
In what Huffyuv and Lagarith differ? is there a reason to prefer one over the other? or at the end is just how efficient the compression is in term of size?

Quote:
When a limit is reached, capture stops.
I do plan to do it while at work. Im assuming I should use a time-limit. How long is the longest VHS tape in term of time (assuming it's full of content)? 4 hours? 5 hours?

Quote:
Timing...
Well this getting more complex. As I mentioned, I own a VC500, and I'm not sure if It has internal audio input and timing correction or not. I'm assuming that I will have to play around and experiment what works best for me. Sadly I don't own TBC device, and it seems almost mandatory. the VCR is a DVD/VCR combo unit, so I assume I will have to try it. But correct me if I'm wrong - Timing only effect Audio/Video sync. So if my Audio/Video sync is fine - there's nothing here that I should worry about? Does it also means I don't need TBC? or TBC does more than just sync audio/video?

I only tried to single capture yesterday before heading to bed, I will fiddle with it more later on. I didn't tested the audio sync, but I check the video itself and it looks like some section along the recording had a problem. I could see a thin strip showing on and off across couple of places. they appears for less than 1 seconds and disappears. I somehow remember this being an issue when I used the VHS, but I'm not sure why. There's a chance the source is the problem, I need to connect the VCR directly to the TV and check. If I see the same when directly connected to the TV - Could it be the VCR itself? I remember we used to play tapes that used to 'clean' the VCR. Was that a real thing? and maybe I need to do it? I will attach more screen shots later of the exact problem after more research.

And lastly, before finding this guide, I found this YouTube video. It mentioned that post capture, it's mostly a good idea to fix the interlaced fields using deinterlace. After doing so, he compress the video at 60FPS, because now that the fields are being deinterlaced, it's not longer 30 FPS.
Is there a guide around on post filtering? filers I always want to use to improve the general quality of the capture?

Thanks again for the guide and help!

-- merged --

I did some more research for couple of questions , I had. Sadly I can no longer modify the original post, but I'm writing the answers for some of the question I wrote:

Quote:
Wouldn't that always be a good idea to use Preview so you can tweak your white/blacks with histogram? - but anyhow - no matter which I choose Preview or Overlay, shuttering or not shuttering - this does not effect capture?
It's possible to set Preview mode, set the Blak/White levels with Histogram, and once set - go back to Overlay. Lordsmurf has mentioned Overlay is takes less CPU/Mem. I'm not sure it's an issue with today's CPU/Mem, but I'm going to try both just in case. I'm still not clear if what's happening in the preview/overlay is what really getting captures (so if the Overlay shutters for example - does it mean the final capture will also shutter?)

Quote:
My default resolution is not 720x570. When I tried to set it, it says the resolution is not supported by the Capture device. I'm using the VC500. Why is that?
That's because I was setting VirtualDub to PAL.

Quote:
In what Huffyuv and Lagarith differ? is there a reason to prefer one over the other? or at the end is just how efficient the compression is in term of size?
Lordsmurff commented that Huffyyuv is a bit safer, because it takes less CPU power. Will be using it to start with.

For everything else, I pretty much still looking for answers :-)
Thanks!
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  #76  
01-15-2020, 06:08 AM
msgohan msgohan is offline
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Quote:
Originally Posted by Okiba View Post
Wouldn't that always be a good idea to use Preview so you can tweak your white/blacks with histogram? - but anyhow - no matter which I choose Preview or Overlay, shuttering or not shuttering - this does not effect capture?
Preview affects capturing in the sense that it uses CPU/RAM and could therefore cause dropped frames. But a stuttering preview doesn't necessarily mean the capture will stutter.

Quote:
My default resolution is not 720x570. When I tried to set it, it says the resolution is not supported by the Capture device. I'm using the VC500. Why is that?
720x576. You may need to set the frame rate to 25 fps first to get the device into "PAL mode". Otherwise it thinks you're forcing 720x576 @ 29.97 or 720x480 @ 25 and doesn't work.

Quote:
Is there is differences between the PAL options? or as long as I can see the the record on the overlay/preview I'm fine as all I checked had the same FPS?
Those are obsolete broadcast variants that will all be the same for tape capture.

Quote:
In what Huffyuv and Lagarith differ? is there a reason to prefer one over the other? or at the end is just how efficient the compression is in term of size?
Lagarith takes more CPU to compress & decompress but produces smaller files.

Quote:
4 hours? 5 hours?
https://en.wikipedia.org/wiki/VHS#Tape_lengths

Quote:
As I mentioned, I own a VC500, and I'm not sure if It has internal audio input and timing correction or not.
It digitizes audio, but you will get A/V desync with the VC500 in VirtualDub if you don't use any sort of TBC. If your combo unit includes a DVD recorder rather than just DVD player, you can try to engage its Dubbing mode to see if it helps.

Quote:
So if my Audio/Video sync is fine - there's nothing here that I should worry about? Does it also means I don't need TBC? or TBC does more than just sync audio/video?
Definitely does more.

http://www.digitalfaq.com/forum/vide...time-base.html
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  #77  
01-15-2020, 06:24 AM
Okiba Okiba is offline
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Hello msgohan! Thank you for the answer. I posted another post couple of seconds before you did answer some of the questions you answer :-)

Quote:
Those are obsolete broadcast variants that will all be the same for tape capture.
In that case, I will just sit it to whatever PAL it currently is (I think B).

Quote:
Oh, awesome. I'm not sure how to identify the Tape type I use. I'll check the Tape home, maybe It got an indication on the TAPE itself.

Quote:
It digitizes audio.
Thanks for confirming it. In that case, I found an early sanlyn post that mentioned for most USB devices works the best with the following time settings, I will start with that:

Resync mode:
[x] Do not resync

[ ] Correct video timing
[ ] Automatically disable resync

Quote:
Definitely does more.
http://www.digitalfaq.com/forum/video-restore/2251-tbc-time-base.html
It actually fix some image quality. Because I own a DVD Record/VCR combo unit, there's a chance it does come with some of the features describe in the document, but it also state being a bad capture device all around. I'll check around, maybe I can a different capture unit.
But there is something I'm not sure about. It sounds like TBC just fix issues with the video buffer. Isn't it something that can be done today with a software post capture? a software that detects the same issues and try to fix those?

Thank you!
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  #78  
01-15-2020, 06:54 PM
msgohan msgohan is offline
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TBCs operate on parts of the analog signal outside of the active video area. In captured files, none of the Vertical Blanking Interval is present and only a portion of the Horizontal Blanking Interval is. So it's impossible for software to correct except by guessing based on image content.

"PAL" uses 625 lines per frame; only 576 of these are the active portion that's captured.

The project below refers to a digitization method and software that bypasses the typical capture card operation, and all processing of the playback machine itself, instead digitizing the recorded signal close to its original form:
VideoHelp thread: Current status of ld-decode / vhs-decode (true "backup" of RF signals)

While I'm very enthusiastic about it, I would say it's still in "alpha" status for PAL VHS, and I think it will only ever be of interest to Advanced users because of how many steps are needed just to get a normal video file that can be played back.

In this YouTube clip you can see how much non-visual information is actually present in an analog video signal. All of those borders are actually part of the recording on tape.
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  #79  
01-16-2020, 02:37 AM
Okiba Okiba is offline
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Oh, I see. Thank you, I didn't know that. It's funny, because today we doing so many amazing things. From landing things on the moon to fully emulating gaming consoles. I guess it's just that not many people are interested in converting VHS to digital format.

That being said, the project looks very interesting, and who knows where it take us later on. The problem I assume is that the source is getting older. I don't know how age impact Tapes, but I'm assuming ages does have some sort of impact.

My folks has a large amount of Video Tapes with us being children. They take a lot of space, and I wanted to digitalize it, and throw those away to save some space. But it looks like I might hold tapes a bit more - as maybe later on, it will be possible to do a better conversion. I might Air tight the tapes in a Vacuum bags to keep them from ages faster.

But to the current setup - I will try to get my hands on TBC, even though it sounds very hard. It's a big unit, and I don't live on the states, to shipping is going to be pretty expensive. I will start without one, and adjust. I'll try to post a sample tomorrow. Perhaps you can tell me if the artifact I see are part of the hardware I'm using or the quality of the tape.

One thing I noticed in almost all videos, is the lower part of the video have touch stretchy white/black lines? Is that the quality of the tape?

Thanks!
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  #80  
01-16-2020, 04:29 AM
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Quote:
Originally Posted by sanlyn View Post
Lordsmurf likes overlay mode, for whatever reason.
The reason is because overlay operates without CPU usage, in the GPU. This results in smoother playback during preview. I see no need for histograms during capture (nor audio meters), the video is what it is. I'll preset hardware proc amps, as needed, by eyeballing the input (something you can do with calibrated monitors, and experience). But then let it capture. I'll mess with histograms, as needed, in the post-capture workflow.

Quote:
Originally Posted by Okiba View Post
I'm assuming this is still correct
This is evergreen content -- it's unlikely to ever go "out of date". Analog video capture has a fixed process, and has for at least a decade now.

Quote:
I'm using the VC500. Why is that?
This card may have mid-production changes, as results have been variables for different users. AGC issues, amongst others, have been confirmed on some VC500 cards. My own VC500 defaults to an excessively dark input IRE/contrast.

Quote:
I'm not from the US. PAL did work. Actually, couple of PAL variants worked for me. PAL G, PAL B, etc. Is there is differences between the PAL options?
You're PAL. No real difference for I/B/G/etc for s-video/composite input. That was mostly an aerial difference.

Quote:
In what Huffyuv and Lagarith differ? is there a reason to prefer one over the other? or at the end is just how efficient the compression is in term of size?
Lagarith has excessive CPU overhead, not recommended for capture, often reported issues when usede for capture. Huffyuv is slightly larger files, but not a major difference. Lagarith does work faster/better for post-capture intermediaries in editing and restoration.

Quote:
I do plan to do it while at work. Im assuming I should use a time-limit. How long is the longest VHS tape in term of time (assuming it's full of content)? 4 hours? 5 hours?
SP mode T120 = 2 hours
LP mode T120 = 4 hours
But depends on tape length (T120, T180, etc), and mode used.

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I own a VC500, and I'm not sure if It has internal audio
All USB cards do.

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Sadly I don't own TBC device, and it seems almost mandatory.
It is. Read this: http://www.digitalFAQ.com/editorials...g-workflow.htm

And specifically, this quoted section:
Quote:
Originally Posted by LS
What does a basic capturing workflow look like?

A basic/minimalist/essential workflow is
- the tape player or camera
- something that does timing correction and/or frame sync
- digital device (computer capture card, DVD recorder, DV capture box/camera)

Again, workflow = sequential steps. The analog signal is played, then corrected/prepped for digital acquisition, and then captured, in that specific order. And the middle TBC step is required, not optional.

But since analog video signal are chaotic, itís not as simple as using any VCR, any capture card, or any device claiming to be a "TBC" (or have TBC functionality). Therefore, the suggested minimal workflow is:
Quote:
Timing only effect Audio/Video sync.
"Timing" is a broad term, meaning many things. In reference to that single setting in VirtualDub, yes, timing refers to audio sync. However, hardware really controls the sync, not software. At best, software can attempt to correct bad incoming (from hardware) audio, but that's it. You can easily lose sync from dropped frames, and that's the the TBC comes in.

Quote:
So if my Audio/Video sync is fine - there's nothing here that I should worry about? Does it also means I don't need TBC? or TBC does more than just sync audio/video?
No, to all 3 questions.

Quote:
And lastly, before finding this guide, I found this YouTube video. It mentioned that post capture, it's mostly a good idea to fix the interlaced fields using deinterlace. After doing so, he compress the video at 60FPS, because now that the fields are being deinterlaced, it's not longer 30 FPS.
The author of that video is a dipshit. If you follow that horrible advice, you'll end up with low-quality videos. And I mean really, really low quality. He's using an infamous Easycap (aka Easycrap) card, and then monkeys around with VirtualDub settings that will easily cause massive amounts of dropped frames.

Quote:
Lordsmurf has mentioned Overlay is takes less CPU/Mem. I'm not sure it's an issue with today's CPU/Mem
The issue persists, even to systems from recent years. It's not the amount of CPU used, but the simple interruption of the CPU being used at all. VirtualDub doesn't operate in more than 1 core, and a single CPU core can get saturated easily, even if briefly (all it takes is 1ms for drops), thus causing dropped frames.

Quote:
Originally Posted by msgohan View Post
But a stuttering preview doesn't necessarily mean the capture will stutter.
Correct.

Quote:
Originally Posted by Okiba View Post
It sounds like TBC just fix issues with the video buffer.
Not entirely.

Quote:
Isn't it something that can be done today with a software post capture? a software that detects the same issues and try to fix those?
No. No such thing exists, and probably never will.

Quote:
Originally Posted by msgohan View Post
The project below refers to a digitization method and software that bypasses the typical capture card operation, and all processing of the playback machine itself, instead digitizing the recorded signal close to its original form:
VideoHelp thread: Current status of ld-decode / vhs-decode (true "backup" of RF signals)
While I'm very enthusiastic about it, I would say it's still in "alpha" status for PAL VHS, and I think it will only ever be of interest to Advanced users because of how many steps are needed just to get a normal video file that can be played back.
... and the quality, at the moment, is unimpressive. I've been asked about it multiple times, weighed in on the thread tonight as requested. It is interesting, bit it's far from truly usable. And (to be honest) will likely end up long-term vaporware, never having lived up to its promise. Still, I wish the developers well, will keep watching the project.

Quote:
Originally Posted by Okiba View Post
today we doing so many amazing things. From landing things on the moon to fully emulating gaming consoles.
Sadly, not really. We've not been to the moon in 50 years, and emulation has been possible for at least 25 years. Due to my own health issues, I'm actually more interested in medical breakthroughs, but that field is sparse as well. We as a society right now really are NOT experiencing an abundance of scientific or technological breakthroughs. Most are just mild improvements on what was discovered in decades past. Video capture is really not much different, same basic processes, hardware and software from 20-25 years ago.

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The problem I assume is that the source is getting older. I don't know how age impact Tapes, but I'm assuming ages does have some sort of impact.
Most physical damage: bad storage, oxide shedding, etc.

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My folks has a large amount of Video Tapes with us being children. They take a lot of space, and I wanted to digitalize it, and throw those away to save some space. But it looks like I might hold tapes a bit more - as maybe later on, it will be possible to do a better conversion. I might Air tight the tapes in a Vacuum bags to keep them from ages faster.
Don't do that. Yes, keep the tape. No, not air tight, as it will trap moisture, then you'll really have problems (mold, oxide shedding, etc).

Quote:
But to the current setup - I will try to get my hands on TBC, even though it sounds very hard. It's a big unit, and I don't live on the states, to shipping is going to be pretty expensive. I will start without one, and adjust.
Timebase correction (TBC) is not optional. Something is needed, even if minimalist TBC(ish) sorts of setups. Do not assume shipping is higher overseas, as it usually is not (I would know, I have TBCs available in the marketplace, and ship worldwide). Feel free to start without one, but you will have issues. Without any TBC whatsoever, you'll encounter dropped frames, audio sync issues, general degraded quality, and often violent errors (false MV detection being a main one, but not the only one).

Quote:
I'll try to post a sample tomorrow. Perhaps you can tell me if the artifact I see are part of the hardware I'm using or the quality of the tape.
Yes, do so -- but in a new thread, not the capture guide thread. We're veering a bit off-topic now.

Quote:
One thing I noticed in almost all videos, is the lower part of the video have touch stretchy white/black lines? Is that the quality of the tape?
Again, post a sample. You may be seeing overscan (head-switching noise), but unknown without seeing a sample image or capture. Again, in a new thread.

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