Welcome to Doom9's Forum, THE in-place to be for everyone interested in DVD conversion.

Before you start posting please read the forum rules. By posting to this forum you agree to abide by the rules.

 

Go Back   Doom9's Forum > Capturing and Editing Video > Capturing Video

Reply
 
Thread Tools Search this Thread Display Modes
Old 1st March 2006, 06:52   #1  |  Link
jmac698
Registered User
 
Join Date: Jan 2006
Posts: 1,862
Component4All Test Results

You asked for it, here are some samples of this new technique.

http://rapidshare.de/files/14402099/...sults.zip.html

I started this thread to discuss the test results. Do you now believe in this technique? Want to see more samples? Any more tests for me to run? Enjoy.
jmac698 is offline   Reply With Quote
Old 2nd March 2006, 22:47   #2  |  Link
jmac698
Registered User
 
Join Date: Jan 2006
Posts: 1,862
What are these things??

These first tests are very technical, and not very satisfying to the layperson. But, if you want to know,

Can a cheap svideo cable ruin the quality of your caps?
No.
Compare bad svideo cable.png vs good svideo cable.png
Here you can see the difference. I find no difference in frequency response. The difference in cost was 15 times!

Does C4All technique have better frequency response than svideo?
Yes, by >1.6 times better.
Compare c4all.png vs good svideo cable.png,
c4all U.png vs svideo U.png

You have fast OR accurate options in your technique. How do they compare?
"fast" has accurate hue/tint in this test, however the green is not very bright/saturated, and there's a slight color cast on the picture.
Compare c4all.png vs c4all-fast.png

You told me to compare these pictures, but what do they mean???
There are bands of color which are large on the left, and decreasing in size on the right. The smaller the band you can see, the higher the frequency that could be captured. There are 5 markers at the very top, indicating: 1,2,3,4,5 MHz. So, in "good svideo cable.png", look for the point where the colors disappear. Now count the markers. I count almost 4 markers. My conclusion: colors stop at 3.75MHz.

More about the bands. These are bands of pure color in a frequency sweep. The "greyness" or luma value is always the same. If a high frequency of color is filtered out, no color gets through, thefore the image shows as grey. The point at which the color disappears is the maximum frequency of color that could get through.

What are these b/w pictures called *U?
This is a direct translation of the color info into a b/w picture. If there is no color, it will be exactly grey all over. Where color appears, there will be some variations of grey. "svideo U" is exactly like "good svideo cable", but only the Cb/Pb/U information is shown. The point of this, is that it's easier to see. It's a smaller picture, because color information is usually lower rez than luma information, in this case YV12, which has only 360x240 color resolution but 720x480 luma resolution.

Last edited by jmac698; 2nd March 2006 at 23:03.
jmac698 is offline   Reply With Quote
Old 3rd March 2006, 04:51   #3  |  Link
jmac698
Registered User
 
Join Date: Jan 2006
Posts: 1,862
test2

Original - some reddish text
svideo - after svideo connection
c4all - after my technique

Compare svideo vs c4all, and see the color resolution. See svideo, and see the smearing.

This gave new information, notice the halos on top of the squares in svideo. They are roundish. That should be impossible. I think my DVD player is using a high quality Chroma Upsampling. That means the YV12 colorspace, where one color is stored in MPEG2 for 4 pixels, is interpolated to a better quality. That explains the curving quality, it happens with bicubic interpolation. Otherwise, there would be nothing on top of the squares; they are on even pixel boundaries and even in size.
Attached Images
   

Last edited by jmac698; 3rd March 2006 at 05:17.
jmac698 is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +1. The time now is 00:32.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2018, vBulletin Solutions Inc.