Awesome XVCD quality.

[BlackAdder]

I just encoded an XVCD and the quality is awesome, near DVD. My source was a very clean dvd rip at 23.976 fps. My TMPGenc template is based on Sefy's. I set "motion search precision" to High Quaility, uncheck Scene Detection, force picture type setting, and set soften block noise to default.


I never believed you could get that good of a picture with TMPGenc.

[homerpez]

The only things I see different on yours than mine is 1- you probably are using VBR with a higher AVG than mine, and 2- you used "Force Picture Type Setting"...

#2 is what interests me, especially if it helps get rid of blocks... what does it do?...

My SeVCD's look very GOOD, but not very GREAT.

<font size=-1>[ This Message was edited by: homerpez on 2001-08-01 13:20:48 ]</font>

[BlackAdder]

Of course "great" and "awesome" is subjective. Maybe we need to come up with a grading scale based on amount of blockiness, color seperation/gradiation, pq in fast scenes, etc.

I'd give my encode a 7 or 8 out of 10 on blockiness
color seperation/gradiation a 6.5 and pq in fast scenes a 9.
10 being the best a vcd can get. DVD's would probably rate about the at about 12 to 15.

Anyway, my post was worded badly. I have Force Picture Type Setting unchecked. Setting block nose to default seems to help, and doesn't increase encode time to much. I haven't done any empiricle tests though.

I think the biggest thing that contributed to the awesome quality is the source. If one thing I've learned from encoding VCD's it's, garbage in, garbage out. The source was large, I think 640x312. I had tempgenc resze it to 320x188 (custom size).

I could create a snipet of the encoded file and email you a link to it if you like.

BTW, I did not change the AVG from your template.

[khai]

What does Scene Detection do? I always leave it checked.

[BlackAdder]

My memory is sorta fuzzy on the exact hows and whys, but here it goes,

It has something to do with having TMPGenc not falsely detect color changes "within a scene" as a scene change. It helps to reduce motion stutter in low motion scenes.

[VidGuy]

What Scene Detection normally does is force an I-Frame whenever the scene changes. I've seen people give long disertations why that's a bad thing in TMPGenc, but CCE does it and I've never seen it be bad. It seems intuitive as well - if the scene changes, basing the frame on prevous frames is probably useless. Apparently, empirical evidence shows that TMPGEnc doesn't do a good job of it for some reason.

<font size=-1>[ This Message was edited by: VidGuy on 2001-08-02 14:06:57 ]</font>

[shochan]

Scene Detection is only good for a vbr style encode, mainly it is for the manual vbr setting. It is not really needed and when unchecked can decrease your decoding time. What it is is when checked it will set a specific number of bits between each scene averaging it out. Example lets say it needs a average of 2000 and you have 3 scenes, it will encode one at 3000, one at 1000 and the last one at 2000, giving you your final average. When you start encoding it will search ahead while encoding to find a given number of scenes and average to 2000 with them along with the I-Frame insertion at the begining of each one it finds. your best bet is to turn it off and stay away from the automatic vbr and the manual vbr.

[homerpez]

I use VBR all the time... and perhaps I spoke too soon...

I just did "X-Men" off my DVD, and it was IMCREDIBLE in TMPGEnc... I saw ZERO blocks. This is with 2-Pass MPEG-1 VBR, MIN 200, AVG ***, MAX 2400 (*** = Whatever needed to fit the movie on 1 CD), "Pad if below MIN" is ON.

Here's what I typically use:

"Sharpen Edge" +45 Horiz and Vertical

"Soften Block" on Default (+35)

"HIGHEST MOTION SEARCH" I know it may be overkill, and I'm told HIGH is fine, but better safe than sorry...


And what I don't use:

"Detect Scene Change" OFF (if you use it in TMPGEnc, it not only adds to file size, but it will create motion stutter just before a scene chages!)

"No Motion Search Per Half Pixel" I always used to check this, but on this encode I left it off, so it would do motion search on everything. To my suprise, it made a difference! I ran it thru TMPGEnc the first time, and it had a few blocks here and there. I turn it off, and they seem to disappear! Maybe just wishful thinking and I'm imagining it, maybe just this movie... oh, well...