Best VHS capture resolution??

[anitract]

LS,

Do you think that AIW 704 captures from VHS source also qualify as overkill? I ask because in my comparisons (using 3 TVs of different size, and 3 differnet DVD players - none of this equipment being cheap) I really do see a better picture than 352.

What I see does not look like artificial detail, but real source-driven detail that is lost at the 352 level. (That is, when you compare either resolution w/ the original VHS source.)

[lordsmurf]

Generally, I'd have to say so.

Also consider this ... is your VCR artificially sharpening the VHS image any? Certain VCRs, Toshiba comes to mind, can also provide a sharper image, albeit fake. Sharp VCRs, no pun intended, also have "enhance" features that can sharpen detail. Again, fake.

I have no trouble with capturing VHS at a higher resolution if you purposely sharpen it. That's great. I have a detailer, a DR-1000, as well as a resolution boost on the BVP-4. It clarifies the image quite nicely. And in order to retain that newly enhanced detail, I have to capture at 704x480 or DVD recorder at 720x480.

But in general, straight transfer, no sharpening, no, no advantages. Sometimes artificial sharpening can be overdone, so the "softer" 352 is a safety net for those that don't know when too much is too much on the sharpening.

[SatStorm]

Hauppauge PVR cards are not good if you wish to use non D1 CCIR-601 framesizes: When you capture at 352 x 576/480 the picture is noticable degraded compared an 720 x 576/480 capture.


About the framesizes, I meant target framesizes: Not framesizes for capture.
A VHS can end up on 352 x 288 interlace mpeg 2 file and look identical the source.
A SVHS can end up on a 352 x 576/480 mpeg 2 file and look identical the source.

The problem is that only 1/3 of the DVD standalones playback 1/2 D1 correct and only 1 / 6 playback 1/4 D1 correct. Yes, you see a picture. But in an awfull way

Also, the "how to" proccess and the "why is this possible" is a long story

What we have to realise here, is that what we capture, is not the SVHS / VHS info, but the VHS / SVHS info spread on a CCIR 601 canvas.
So, when we capture, we capture the canvas with the VHS / SVHS info. Not the VHS / SVHS info alone.
And the easier thing to do later, is to encode that canvas "as is" to mpeg 2.

If we wish to keep only the VHS / SVHS info of that canvas, in a way we have to "extract" it from it. What end ups, is not 720 x 576/480 for sure. So yes, 720 x 576/480 is an overkill for VHS / SVHS but not an overkill to capture the canvas (the area) that this info is spread!

And even if we made it (with various technics) end up only with the usefull VHS/SVHS info, we have a dilema: Or we can choose to emulate what analogue do (and that is the hard way), or we use the "default" settings and encode to what the average DVD standalone can playback excellent.

My point is that it is possible to convert a VHS tape to 352 x 288 if you are PAL and look the same the source (this is not possible for NTSC, there you need 480 vertical lines to have interlace).
But you won't made it if you capture straight to that framesize.

[vhelp]

Evening everyone

I was bored, and thought I'd jump in as well.

Without going into much detail here with you all
(I'll spare you.., this time around)

Very briefly..

VHS and prefered capture resolutions ...

.
some meat here I'll skip over..
.

If your end goal is just to watch the vhs -> dvd-r transfer on a
small tv set, say something around 27" or 32" or smaller size,
then finalizing to 352 pixels is find. Actually, people use this
for bitrate realestate/distribution purposes per dvd-r disk which
is usually for 2hr programs.

In this case, I would not recommend capturing to 352 unless your
capture card provides an even resize method.. ie, 352 and 704/720
pixels and is already known for it. I think there are a few ATI
cards in this area. Brainstorm69 provided a few shots, I beleive.
If memory serves me correctly. As I was saying..

I would suggest or better, recommend that you capture at 720 (after
determining 720 is good for your cap card, else use the determined
resolution of your given cap card) and then if you feel like, resize
down to 352 for a final MPEG. Again, if you are only planing on viewing
on a small screen tv set.. 352 is fine, after a proper resize.. yada yada.

But, if your end goal is to watch your vhs -> dvd-r transfer on a
LARGE tv set, then you are better off *defintately* capturing at
the 720 pixels (or whatever you have determined that your capture
card's "natural" capture pixel number is, and you have added in the
appropriate PADDED pixles.. ie, 8 pixels left and right for a 704
pixle, or 16 pixles left and right, for a 720 pixel) and then you
finalize to a 720 pixel MPEG's.

.
some *MORE* meat here I'll skip over..
.

@ ForYouAndI

I think that you should post your specs (all of them) and your
given setup.. ie, vcr; source tapes; age; source type like cable or
antenna recorded to tape; etc.

fwiw..

So that we have a better scope of what you *really* are looking
for in this endeavor. Quality or space per disk. I don't know
what you *really* want or are looking/searching for. But, I do
not agree with 352 IF quality is your main objective after all.
And, if your end goal is JUST FOR TV VIEWING (on small size tv)
then I don't think you are looking for quality reproduction in
the end.. but rather something to throw onto dvd-r 's to be done
with it. I dont' know. I'm just speculating now

-vhelp 3579

[lordsmurf]

VHS / SVHS info spread on a CCIR 601 canvas.

And that's an important concept to remember. And it's goes beyond just resolution too, but to all aspects of the video signal.

[davideck]

I think vhelp nailed it!!!

[BrainStorm69]

You might try reading this thread:

https://www.videohelp.com/forum/viewtopic.php?t=235585&start=60&postdays=0&postorder=asc&highlight=

Unfortunately, some of the pictures posted got lost in a server move/hiccup of some sort. But still a very good thread as I recall.

BTW, if you want to determine the capture window of your video card, go here:

http://www.doom9.org/capture/capture_window.html

[anitract]

LS, I use the same equipment to both view and capture either 352 or 704 size...so any artificial sharpening or what-not would occur on both resolutions...so its a moot point.

I don't know, it's pretty clear to me that 352 does not scale as well when viewed on my 36" TV. On my 13" it looks about the same as 704, but then again not on my 24" WEGA. So that tells me that in most cases I'd want 704, so I'll just stick with that.

I use a JVC SR-V101US for all my captures, BTW.

[anitract]

In the old thread BrainStorm69 posted, this POST by junkmalle interests me. The 720 mpg that is resized to 352 looks nearly identical (or better?) than the actual 352 capture does. Why is this? I had thought that any resizing of mpgs was seen as degrading the quality. What am I missing?

[davideck]

Higher bandwidth signals require higher sampling resolutions. I don't think anyone is disputing that.

The issue at hand is whether or not 352 sampling is sufficient for VHS resolution. Some say yes, others say no.

IMHO, it is such a close call that it depends on the specific setup and the detail level of the source.

It is reasonable to claim that some VHS tapes and some setups show no improvement at 704/720. It is also reasonable to claim that some VHS tapes and some setups do show improvement at 704/720. (junkmalle's Post demonstrates this.)

I would recommend that anyone who notices improvement at 704/720 capture that way.

[junkmalle]

It has to do with filtering. Good resizing algorithms like VirtaulDub's Lanczos3 blur the image slightly before resizing, then sharpen afterwards. This reduces aliasing artifacts. Exactly how the results turn out depends on how much the image is blurred and sharpened in the process. The Hauppauge cards appear to be (overly?) aggressive in their aliasing prevention when capturing at 352x480.

[anitract]

junkmalle, that makes sense...sort of.

Hmm...now it makes me wonder if in some cases capturing at 704 (my best res) and then resizing to 352 using Lanczos3 would create better 352 files than a straight cap to 352. I'll have to experiment tonight.