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BrainStorm69
Tobor
Joined: 05 Aug 2002
Location: Texas, USA
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We have had a very successful (and I believe useful) thread about why one would need a VCR with an internal TBC even if you are going to use an external TBC also. Link to that thread is here:
http://forum.videohelp.com/viewtopic.php?t=289311
In the course of that thread, some have expressed an interest in starting another thread where we have a test vob with some color purity and image quality tests. I have created a test vob to hopefully use for this. It has our old standbys from Ice Age and a couple of other test patterns that might be beneficial. It can be downloaded here:
http://s52.yousendit.com/d.aspx?id=1OSIQERCMRODB274SFIOHV116P
This is a 20MB zip file, so if you want to download it, I hope you have a fast connection.
In the interests of as much consistency as possible (and to at least note where your testing methodology was different), I'm going to suggest some instructions for posting here.
1. Download the test vob zip file from above
2. Unzip into an empty TS_VIDEO folder
3. Burn TS_VIDEO folder to DVD using your favorite burning program
4. Place Test DVD in stand alone DVD player and capture directly to your capture device from DVD (we'll use this later for reference) at full D1 (or as close to that as possible) resolution. Note the DVD Player make and model, capture device make and model, what format you captured to (e.g., avi using HuffyUV), and whether you used s-video or composite cables (and brand and model). For these tests, let's not use an external TBC.
5. Place in Test DVD in same stand alone DVD player and tape the output to VHS, preferable using a new (or at least good condition), high quality VHS tape. Note the brand and grade of VHS tape used. Note the make and model of VCR used. Note whether you used s-video or composite cables (and brand and model). PLEASE TAPE TO VHS, NOT S-VHS OR S-VHS ET.
6. Place VHS test tape in VCR to be tested and capture directly to your capture device at full D1 (or as close to that as possible) resolution. Note what format you captured to (e.g., avi using HuffyUV). Note the make and model of VCR used. If your vcr has any special image quality settings, note what they are set to. Note whether you used s-video or composite cables (and brand and model).
7. Use Vdub or Vdubmod to make screen caps. For each test scene you want to cap, please count 30 frames into the scene after the transition between scenes has ended. You can do this in vdub by using the right arrow on your keyboard. It's one frame per right arrow button push.
8. When you get correct frame, click on the "Video" on the menu bar, and then click on "snapshot source frame" on the dropdown menu. You will get a dialog box to save. It will have an option to save as .tga, .bmp, or ,png file. I would save as a bmp and then use your favorite image application to save as a jpg using whatever compression you need to make the file 150KB or less (since that what the forum rules require for posting images).
9. Post a test image screen cap from your DVD player directly to your capture device (for reference). Post your test image screen caps from your VCR.
If I forgot something, let me know. I'm about to try this with my Panasonic AG-1980.
Last edited by BrainStorm69 on Jan 29, 2006 16:52, edited 1 time in total
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BrainStorm69
Tobor
Joined: 05 Aug 2002
Location: Texas, USA
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Wile_E
Desert Wanderer
Joined: 12 Jul 2004
Location: Texas
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Would it be okay if I just play the VOB on Vegas timeline, out to Canopus ADVC, and into VCR? Like I did with other tests? That way, it takes the DVD Player out of the loop. I only have a Panasonic S47 DVD Player, and it doesn't have proper 7.5 IRE setup as far as I know. Only lighter/darker settings.
I prefer the AG-1980 output, even though it is much brighter. Less noise, and looks like more detail was preserved. I am viewing in Paintshop Pro, where I can zoom in the images and switch through them rapidly. Everyone else should use a similar method to view the images.
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BrainStorm69
Tobor
Joined: 05 Aug 2002
Location: Texas, USA
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| Wile_E wrote: |
| Would it be okay if I just play the VOB on Vegas timeline, out to Canopus ADVC, and into VCR? Like I did with other tests? That way, it takes the DVD Player out of the loop. I only have a Panasonic S47 DVD Player, and it doesn't have proper 7.5 IRE setup as far as I know. Only lighter/darker settings. |
Wile_E, you can do it anyway you want. But as far as the set-up on your Panasonic DVD player, that's why I suggest a cap directly to your capture device from the DVD Player for reference. Then we can see compare caps of what was being fed to the VCR vs. what the capture from the VCR looks like. The caps I posted from the DVD are not DVD rips, they are captures straight from the DVD player (source). I don't think you can do that using your method because you use the ADVC to play to the VCR and then you use the ADVC to cap from the VCR, dont you? The ADVC won't let you loop its output into its input, will it (and I wouldn't necessarily try it, might damage something)?
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jagabo
Member
Joined: 09 Dec 2005
Location: none
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BrainStorm69, Nice work and interesting thread. I did notice one problem though. You seem to have a 4:2:0 chroma subsampling problem somewhere along the line.
If you look at the original VOB file, the second S&W image has a small 4:2:0 chroma test patch. Extracted from the VOB file with VirtualDubMod it looks like this:
crop:
2x enlargement (nearest neighbor):
As you can see, one field is cyan and the other is a yellowish gray.
When I use the s-video output from my graphics card to a 32" SD TV I can see the patch just as displayed above (although it's borderline, the TV is just barely able to resolve it). Playing off a DVD looks like that too. If I capture the video with my Hauppauge WinTV PVR-250 it also captures the image as depicted.
But all your caps show a solid (more or less) light green. Somewhere along the line the 4:2:0 video has been mishandled. I know this wasn't what you were testing for but I thought I would mention it.
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BrainStorm69
Tobor
Joined: 05 Aug 2002
Location: Texas, USA
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| jagabo wrote: |
BrainStorm69, Nice work and interesting thread. I did notice one problem though. You seem to have a 4:2:0 chroma subsampling problem somewhere along the line.
But all your caps show a solid (more or less) light green. Somewhere along the line the 4:2:0 video has been mishandled. I know this wasn't what you were testing for but I thought I would mention it. |
@jagabo - nice catch. I went back to my uncompressed bitmaps of the screen caps to see if they display the same problem. They don't. So the problem is not in the capture process, it's in the conversion of the screen cap from bitmap to jpeg.
EDIT: It's sort of a bummer that some detail is lost to fit the file size restrictions, but I can understand the need for them. 
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Wile_E
Desert Wanderer
Joined: 12 Jul 2004
Location: Texas
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jagabo
Member
Joined: 09 Dec 2005
Location: none
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| BrainStorm69 wrote: |
| I went back to my uncompressed bitmaps of the screen caps to see if they display the same problem. They don't. So the problem is not in the capture process, it's in the conversion of the screen cap from bitmap to jpeg. |
Look to see if your JPEG compressor has a 4:2:2 mode:
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BrainStorm69
Tobor
Joined: 05 Aug 2002
Location: Texas, USA
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@Wile_E - I think our 9xxx caps are pretty similar, although the color is a bit different, and my 9900 is a bit darker. The AG-1980 is definitely sharper, but also has much more noticeable "ringing" on the right side of objects. I may need to try some alternative settings on the Panny. I am assuming the "detail" function may be causing it.
@jagabo - I couldn't find any such option in Paint Shop Pro or LView Pro. What app did you use to convert to jpeg?
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jagabo
Member
Joined: 09 Dec 2005
Location: none
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| BrainStorm69 wrote: |
| @jagabo - I couldn't find any such option in Paint Shop Pro or LView Pro. What app did you use to convert to jpeg? |
I used Ulead PhotoImpact. You can select between 4:4:4, 4:2:2, and 4:1:1 subsampling when saving as JPEG.
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sanlyn
Member
Joined: 06 Oct 2004
Location: NY, USA
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No matter how you play it, how you capture it, or how you wire it -- JVC tape machines have always had a soft, boring image that looks overprocessed. I've been auditioning JVC VCR's since 1990, and I still have tapes made from my earliest JVC machines as well as the latest (2005) JVC's. I sold/pitched-out/returned every one of those JVC's, and I've had one heckofa time trying to transfer those tapes to DVD without seeing blurred details, contrast loss, and really bad noise in shadow areas. Meanwhile, 20-year old tapes I made with my since-deceased Sony's and Panasonics snap to life like prime-time broadcast stuff.
However...a lot of people like soft VHS and SVHS images that have been thoroughly over-scrubbed. In that case, I would suggest that a $500 or better JVC of any vintage since the invention of analog video tape is the answer to their prayers. An alternative would be several late 90's Panasonic and Sony s-vhs machines which were high-end JVC's in disguise. These, too, will give the soft, milky images these users seek. If you have a capture device that can do a strong re-coloring and sharpening job on the incoming pic, you'll get some idea of how much damage an overly aggressive noise reduction circuit can inflict on a VHS image.
I'm glad the original post included images other than test patterns. However, I note that many users avoid image sources that contain real-life objects. But that's for another forum.
_________________
Still Lookin'
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BrainStorm69
Tobor
Joined: 05 Aug 2002
Location: Texas, USA
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| sanlyn wrote: |
| I'm glad the original post included images other than test patterns. However, I note that many users avoid image sources that contain real-life objects. But that's for another forum. |
Actually, I thought about including one more image that I personally like to use from the Spiderman DVD, but I thought that 4 was already getting a bit much for some folks. I may do some tests with that image later and post them.
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Wile_E
Desert Wanderer
Joined: 12 Jul 2004
Location: Texas
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BrainStorm, I was comparing your AG-1980 caps to the original DVD cap, and I think you over sharpened too much. There is a halo effect on the right side of the text. The text though, does look nice and sharp compared to all other caps. The iceage image does look too sharp too, IMO.
I may post my AUTO results soon. I was comparing EDIT/AUTO last night, with R3 off/on. AUTO looks best with R3 on in the iceage cap. AUTO does get rid of a lot of noise, but softens picture noticeably. R3 helps by sharpening it back up. EDIT looks best with R3 off. If I turn R3 on, it looks oversharpened to me. But even EDIT doesn't look as nice looking as the AG-1980 caps.
Could you post a capture with AG-1980 of the IceAge pic, with the slider in default position and use a normal mode, not sharpened? I would like to see how good the AG-1980 in default mode.
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gshelley61
Frequent Flyer
Joined: 19 May 2004
Location: USA
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One of the the main concerns when converting VHS to DVD is what to do about the video noise inherent in that format. Grain, streaks and chroma noise can cause very noticeable MPEG2 encoding artifacts... so one must do something about video noise prior to encoding in order to create decent looking DVD-Video from VHS.
Thankfully, many DVD recorders have input video noise filters. Some do a very good job of suppressing grain and chroma noise, and even have TBC's to deal with time base errors. So, it is possible to use a VCR that does not have any built-in noise filtering or a TBC and still get a very good capture.
For those who capture to MPEG2 with DVD recorders or computer video cards that don't have effective noise filtering built-in, the JVC VCR's that have their TBC/DNR circuit are excellent. They take care of the time base errors and reduce grain and chroma noise significantly, allowing for a good conversion to DVD. The problem I've had at times with other high quality VCR's like the Sony SLV-R1000 and the Panasonic AG-1970 is not with their playback detail, but with their inferior or non-existent noise filtering, particularly chroma noise.
All luma noise filtering methods (which reduce streaks and grain) soften the image somewhat. There's really no way around that. Chroma noise can be suppressed without affecting the detail as much. Time base correction does not affect the detail or sharpness of the image.
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swiego
Member
Joined: 02 Mar 2005
Location: United States
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How do I surpress luma noise filtering in the JVCs? I turn off the DNR and still get comparably soft images from my JVC. I don't want the JVC to do any kind of filtering at all, should I desire that option - I want to capture to PC, uncompressed, and deal with the video data in a medium where I am more comfortable and have more control.
Is it possible to get an unprocessed stream from the JVC to a capture card with just TBC, not any kind of filtration, being done by the JVC?
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gshelley61
Frequent Flyer
Joined: 19 May 2004
Location: USA
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Not with JVC machines that have TBC/DNR. The TBC and DNR are tied together. They are separate on Panasonic AG-1970 and AG-1980 VCR's, plus these units have a variable sharpness control. The Sony SLV-R1000 (and the SVO-2000) does not have a TBC or DNR, but does have variable sharpness. Earlier high end JVC units that did not have the TBC/DNR feature frequently had variable sharpness controls, too (like my BR-378U, for example).
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gshelley61
Frequent Flyer
Joined: 19 May 2004
Location: USA
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One more thing - I mentioned this in the other thread that spawned this one.... but it is important because I think people are getting a little hung up here. Consumer VCR's generally use narrow gap heads that are much better suited for playback than they are for recording. That's one of the reasons that some of these VHS test recordings you guys are making look so bad. Commercial VHS duplicators (the machines that store-bought VHS movies are made with) use special wide gap recording heads and can produce a much better recorded image than is possible with a consumer VCR. Even prosumer editing VCR's compromise in this area as they are made to do a reasonably good job in both recording and playback, but are not necessarily optimized for either purpose.
The "Titanic" store-bought VHS I have is a particularly good example. It is one of those THX certified tapes and looks pretty decent for VHS. A consumer VCR with narrow gap heads is not capable of recording a VHS image that good, but is perfectly suited to do a good job of playing it back.
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lordsmurf
Video Restorer
Joined: 10 Jun 2003
Location: Want my advice? PM me.
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| sanlyn wrote: |
| No matter how you play it, how you capture it, or how you wire it -- JVC tape machines have always had a soft, boring image that looks overprocessed. . |
Personally, I think this is horsecrap. VHS is a low-res format. But even if you believe this, then simply add a detailer from Vidicraft or SignVideo.
If you dislike Sony, JVC and Panasonic, there's not much left. I'd like to hear your idea on what would be an excellent player.
_________________
digitalFAQ.com -- Help with VHS to DVD, DVD recorders, other video/photo issues.
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BrainStorm69
Tobor
Joined: 05 Aug 2002
Location: Texas, USA
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| Wile_E wrote: |
| Could you post a capture with AG-1980 of the IceAge pic, with the slider in default position and use a normal mode, not sharpened? I would like to see how good the AG-1980 in default mode. |
Wile_E, here you go. One each of normal, edit and detail all with the slider in the middle position, and the TBC on. I haven't looked hard at them yet myself to determine any differences.
Normal setting - sharpness slider in the middle - tbc "on"
Edit setting - sharpness slider in the middle - tbc "on"
Detail setting - sharpness slider in the middle - tbc "on"
I read something in an old review today that seemed to indicate that the slider doesn't really function unless you have the "detail" on. Not sure if that's true or not, I'll have to check it out.
@gshelley - you mentioned something above about the DNR and TBC on the AG-1980 being separate. I don't see anything to turn DNR on or off. Am I missing something? Or it DNR always on?
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gshelley61
Frequent Flyer
Joined: 19 May 2004
Location: USA
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Maybe it's separate just on the 1970... that is my recollection (which might be wrong, of course!)
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BrainStorm69
Tobor
Joined: 05 Aug 2002
Location: Texas, USA
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Just for good measure
JVC 9900 - auto - R3 "on" - TBC "on"
JVC 9900 - edit - R3 "off" - TBC "on"
@gshelley - I don't know about the 1970, but I thought they were pretty much the same as far as controls.
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gshelley61
Frequent Flyer
Joined: 19 May 2004
Location: USA
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Yeah, I just had a look at a picture of a 1970... no DNR. Just TBC only. I'm probably thinking of the AG-7750 broadcast deck. It definitely had different controls for the noise reduction and the TBC.
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BrainStorm69
Tobor
Joined: 05 Aug 2002
Location: Texas, USA
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