Better to capture @ 480 for VCD?

[TMcD]

Is it better to capture a TV show @ 480 (vertical) and then let the encoder decide what is best for the VCD (240) lines?

Or is it just a waste?

Thanks,
Troy

[Nexzus]

I've found it's better to capture at the highest resolution your capture card can handle and then convert it down to the format you want. I'm getting excellent results capturing VHS tapes at 720 x 480 and then converting down to VCD. I tried capturing at VCD resolution and the picture isn't as good as if I capture at the higher res and then convert down. I've read many posts stating that VCDs look better when created this way and I'd have to agree with them.

[TMcD]

Thanks.

I'll give it a try. I've done up to 480 x 480 and haven't really tried to compare.

Thanks again,
Troy

[Beavis]

Capturing TV at 480 vertical resolution and getting both fields will probably give you a better VCD in the end. Capturing at higher horizontal resolution is different and will make little or no difference in the end. Your best bet would be something like 352 x 480 (NTSC) and then encode.

[TMcD]

I heard that about the horizontal resolution.

But then why do DVDs use a higher horizontal resoultion?

[TMcD]

Anyone want to take a shot at the question:

Why do DVDs have higher resolution than 352 if horizontal resolution doesn't really matter?

[shochan]

It really doesnt matter for the average person, or the average tv set for that matter. aside from bitrate that is why dvds look better even on the pc is because thaey have a higher resolution and you dont have to stretch it like you do a vcd to get to 640x480 (your tv resolution) you have to shrink it. so actualy it is the same as capturing at a higher resolution, better quaity can be achieved at higher resolutions.

I hope that helps

[TMcD]

Thanks, that does help.

Troy

[wcb4]

<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR size=1 color=black></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>
On 2001-12-25 19:59:37, Beavis wrote:
Capturing at higher horizontal resolution is different and will make little or no difference in the end. Your best bet would be something like 352 x 480 (NTSC) and then encode.
</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR size=1 color=black></TD></TR></TABLE>

I've posted this before, and no one seems to agree or disagree on the point, so I will re-state it .....

there is an old photoshop trick that we would use when scaling iamges to get the smoothest scaling (useful for getting rid of noise without having to actually run a noise filter) and that is to make sure you scale in non-even percentages, not 200, or 150, but soemthing like 203 or 151. This being the case, since the final result will be 240 high, you can't really do anything about capturing at 240 or 480 (even percentage, 100 or 200%) but you can do something about the horizontal percentage. don't capture at 352 or 704, use 640 or 720, 640 scaled down to 353 is 55% percent (not ideal, but not bad) 720 to 353 is 48.8% which is even better) if you capture at this resultion and then have the encoder scale down, much of the noise in a noisy picture goes away without having to run a soften or anti-noise filter.

As I said....this was an old photoshop trick to scale things up a little more than we should or scale them down much more smoothly than they would otherwise (we would actually compute 2 percentages to scale down to get the desired final percentage and scale the image twice). If you original image is really good quality, capture at whatever you like, but television often has a bit of noise so this may help

[TMcD]

Interesting.

I'll give it a shot.

Thanks,
Troy

[Anonymous65]

Regarding DVD has higher resolution then 352, that is bacause a DVD has much higher resolution (detail) than a VCD (VHS). Most good TV's can display 640x480 pixels, which is full resolution NTSC video broadcast. DVD is actually a little better than full broadcast television. Since you use the S-video (or composite) input to the TV, the bandwidth is not limited by the tuner (640x480) and more detail can be displayed if the TV/monitor has better bandwidth. Good monitors should have no problems displaying 720x480 pixels. This is better quality then any brodcast station can deliver which is limited to the 6MHz channel bandwidth on the air (4.2 MHz for video, rest for audio and safe space).
Also, what pixel resolution to use is best determined by the quality of the source material. Taking a DVD to VCD you will loose a lot of video quality, but taking a VHS tape recorded from an off-air TV station to VCD you will not loose much at all. So, when talking about resolution, you always have to think about the source material. Making a 720x480 copy of a VHS tape is kind of waste of bandwidth because the VHS tape can only have around 320x480 pixels of detail.
The vertical resolution is fixed at 240 or 480 pixels because of the number of scanlines per field and frame you can capture. The clever "trick" of going to 240 from 480 pixels in the vertical plane is not the same as cutting the resolution in half. Think of NTSC video being 60 frames (actually fields), but only saving 30. This reduces the frame (field) rate, but not the resolution. This is not completely true, but is a better description then saying going from 480 to 240 pixels is the same as cutting the resolution in half, because your're not. You're cutting the field rate in half. And if you use 2:1 reduction during capture, you combine two fields into one frame so you don't loose any information. This is a neat trick you can use in making VCDs, which has the resolution of 352x240, aka VHS type of quality. VCD is not at all a substitute for a DVD, and was never meant to be. It was meant to be a substitute for VHS quality video. And done right, it sure looks very close in quality. Order a few commercial VCD's, and check them out.

[TMcD]

Skittlesen,

Is using the 2:1 (say serving from VirtualDub) to TMPGE and using the VirtualDub 2:1 filter the same as serving to TMPGE and just setting the template size to 240?

I know that probably is a dumb question. (Or does this just throw away 240 fields?)

Thanks,
Troy

[sommersby]

wcb4 is absolutly correct, and alot of us here ahs seen his post and agree with him, when I want the best capture from vhs or laser disk I always capture at 640x480 using picvideo or huffuv, this gives me great results in my vcd.

[vhelp]

nighty-night, this late night all. . .

I too have ben dabling with VCD's this past weekend. I have finally made some really
good looking quality VCD's, though I still prefer my xSVCD's, I'm just experimenting
on the edge here. And still at it. I have another issue or too to debug or work out.
But, I'm amazed at what I have accomplished this weekend. And this is not an
xVCD, its by the books MPEG-1, 352x240, 1150k (but I use 128k audio) - ok, close.

In reading some of the posts here, I've found some to be quite interesting. I may
add some to my debuging.

HISTORY:
---------------
I made several exploritory DVD RIPs this weekend and did many "what-if's" and "a little
of this" and stumbled accross whta looks to me like VHS or better quality VCDs with,
as far as I can tell, "no blocks". But, like I said, these are DVD RIPs I've ben doing.
When I play these sample encodes on my PC monitor at FULL SCREEN, they look kind
of blocky and whatnot, but when I burn them all to CD, they looks absolutely wonderful.
I left a 5.3MB sampe in my Shared foldre via Morpheus. If you can see it (2 servers)
you can D/L it and burn it to CD. I did these clip testings in Standard VCD format,
no upping up the birtrate to get rid of the blocks!!
I'm still in the middle of my VCD testing. My goal, is to try and stick to the VCD standards
as much as possible. And, so far, I've have done just that!
Oh, the name of the clip I made is: "vhelp-11a-122901-13-5th-element-stndrd-vcd.mpg"
I figured out how to Catagorize my clips and things. Hopefully, it will be registered on
Morpheus's main/master list. I name the clip's Artist, "vhelp" if that helps in searching.
Some key words to search for are "vhelp", "fifth element", ""5th element", etc.
On this computer, (my first pc) I'm logged in as vhelp2, my 2nd (dead pc at the moment)
is vhelp.

...Well, it's getting late, and I wanted to try a filter or too on some of my test rips.

-vhelp

[The1User]

Hello All,

"VCD is not at all a substitute for a DVD, and was never meant to be.
It was meant to be a substitute for VHS quality video. And done right,
it sure looks very close in quality.
Order a few commercial VCD's, and check them out. "

I Can't Encode Good Quality VCD's

I Can Make Good VCD From Files I Download, But Not From My Own Clips

Is There a better Way to Convert from Dv to VCD than Using TMPGEnc (2.02)?

Or is There a Better Way to "capture" the DV ?

I have a Dazzle Hollywood DV Bridge

The DV Looks Great on the Computer, And Sent Out the 1394 Card to the Dazzle Hollywood DV Bridge,
Coverted back to Analog Video and Sent to my 27 " Sony it looks GREAT to...

When I Take That DV and Encode it to VCD it Looks Terrible

The Funny Thing is, Music Video's I Download and Make into VCD Look Great

Lastly: Does Anyone Know of a Better Way of Getting My Video Off VHS Tape
than the Dazzle Hollywood DV Bridge??

I Have VHS Tape of My Kids Going Back 10 years, I Need to Get it Off the Tape in the Best Quality

Thank You

Joe

[Anonymous65]

Copy:
Is using the 2:1 (say serving from VirtualDub) to TMPGE and using the VirtualDub 2:1 filter the same as serving to TMPGE and just setting the template size to 240?

Tmpeg will do the reduction and not just trash the 240 extra lines. I'm not sure what method Tmpeg uses to resize, but Bicubic is the best way to get the most detail and sharpness when downconverting the frame size.
Since I want to save on data saved on the hard drive, I use the 2:1 vertical reduction *during* capture in Vdub. This makes the file half the size! Simply select 352x480 as the frame capture size, and turn on 2:1 vertical reduction. The saved file will be 352x240 of very good quality. If you don't like the blurr that happens during heavy action, or can't capture at more than x240, you can gain about the same extra sharpness (detail) by capturing at 704x240 and then do a 2:1 horizontal reduction.

[TMcD]

Where is the vertical reduction filter?

All I have is 2:1 which reduces both horizontal and vertical.

Thanks,
Troy

[TheInformer]

Quote:
__________________________________________________ _____

"I'm not sure what method Tmpeg uses to resize, but Bicubic is the
best way to get the most detail and sharpness when downconverting
the frame size."
__________________________________________________ _____

skittelsen:
I beg to differ with you on "bicubic is the best way ... when downconverting". At this point I cannot call myself an expert or even really knowledgable on anything but these folks say that bilinear is the way to go when downconverting, i.e. 720x480 --> 352x240 (for example):

http://nickyguides.digital-digest.com/bilinear-vs-bicubic.htm

Bilinear for downconverting, Bicubic for upconverting.

Just my two cents.

[bbb]

Looking at Nicky's page, I noticed that Bicubic is better for enlarging and for shrinking. Bicubic (for enlarging and shrinking) has better picture clarity, color range, and is pleasing towards the eyes.

The Bilinear shrinking washes out the color, dulls the shadows, blurs the picture, Plus, it's still blocky! Just because a webpage says Bilinear is better doesn't mean it is true. Use your own eyes and judge for yourself.