2 pass vbr or not?

[dick bininya]

whats up guys and girls,
im making svcds with Tmpgenc and i had 2 questions
1.should i use 2 pass vbr, and when i do does it take longer to encode than if i didnt?

2.instead of using a vbr, can i use a cbr and still have a svcd format as the result? i figure the cbr will look better, and then i dont have to worry about the max, min and avg bitrate settings.

ok i lied heres the third and last question.....

3.what is the 3:2 pulldown option for? do i need to bother checking this what will it do?

just a few questions for the more "experienced" rippers out there.

thanks in advance!
(.)(.)

[YoshiRuler]

Im not exactly sure on 2 and 3 so heres your answer to #1

2pass VBR makes your MPEG higher quality, and it does take longer, about 2-3 times longer acutally.

[dsa44]

2 pass vbr will take about twice as long

Don't use cbr (constant bit rate) This wastes bitrate on scenes that may not need it. Instead use vbr or cq (constant quality) set to 65.

3:2 pulldown, I just discovered, somehow affects if you have encoded a 29 fps movie to 23 fps OR keeping the 16:9 aspect ratio. I am not quite sure myself (but I think the latter) as I have been just playing around with it more in my limited time. So no flames please, but any more input from more experienced users would help.

[tinmancp]

2 pass vbr is nice, but is too long. I've been using mvbr and the quality is just as good as vbr. My total encoding time for a 1hr30min film is ~3hrs using mvbr while ~6hrs using 2 pass vbr.

[ktnwin]

CBR is good too if it is set to above 2400 (that's what I have done anyway). It may waste some space on the CD-R since some of the scenes may not need that bitrate.

Lately, I always do CQ_VBR (set to 100 for top quality). It ends up to be near the max bitrate always (min 1100, max 2500 and the log shows everything is almost 2500).

I never put more than 40min on a 80-min CD-R so this works fine for me (with very high quality).

[ya_jai]

I have some comments for you
I use CQ on SVCD and VBR, CBR on VCD, never use 2 pass because it takes too long to encode.
About 3:2 pull down I think you must apply this option when you rip at 23.976 fps (use forced film when ripping with dvd2avi)and only with SVCD.

[shochan]

1. Use 2pass vbr. it allocates the bits that need to be where they eed to be. anything else is worthless and will produce a crappier quality. ( whoever wants to argue go ahead.. you are wrong.. I am sorry.. dont waste your time fightning it..)

2.what the other person said it wastes..

3.i assume you are talking about the option under advanced. if so, you use 3:2 pulldown when you want to turn a source from 23.976 or 24 fps to 29.97fps, which is what NTSC is. I have never needed to do this and if you are makeing a svcd and your source is 23.976 or 24 fps then use the option the the first settings tab to do 3:2 dropdown when playback. and it will make your hardware do it instead of the tmpge. that way you dont have to deinterlace it.

<font size=-1>[ This Message was edited by: shochan on 2001-07-24 17:50:24 ]</font>

[poopyhead]

shochan, heh...

i personally think 2 pass vbr is a waste of time...just like using highest quality (slowest) rather than high quality (slow) for motion search accuracy...

unless u can spend twice as much time to encode, then knock yourself out w/ the 2 pass....otherwise....vbr with a pretty high cq setting is good for the encoding time...2 pass is especially long when encoding at higher bitrates

[adam]

someone mentioned that they use the CQ_VBR setting at quality level 100. This is a VERY inefficient method of encoding. At 100 you are essentially encoding in cbr...the result is identical. Except since it is at least trying to use vbr it takse much longer. Either drop the quality setting way down or just encode in straight cbr.

To each his own, but I personally feel that anything other than 2 pass vbr is a waste of time, that is if space and quality are both of concern.

As shogun said about 3:2 pulldown, enable it in the video tab if you are encoding a svcd to 23.976. I think people get confused about this because the option is also available in the advanced tab but honestly I dont see any reason to use that one, just ignore that one. If you want a detailed description of what the 3:2 pulldown function does just do a forum search, it has been talked about extensively.

[dick bininya]

ok thanks!,
i guess i need to use a 2 pass,
so what settings work the best to get rid of blockiness,
and have a great picture, but not having the avg movie go above 2 cds?
thats all i ask.
so i need to know the settings for
avg br
max br
min br
and any other good twaeks or methods you guys find great results with.

thanks again, you guys really make some good points.

[ktnwin]

adam,
I am the one who does CQ_VBR at 100. I have tested CBR and got almost exactly the same result. However, there is a very subtle difference: when the scene are near static (very little change), the bitrate does drop down (look at the log file)
I fully understand the CQ_VBR 65 will yield a much more efficient file size but I care more about quality than file size. I guess it's just me.

[homerpez]

<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 2001-07-25 09:41:35, dick bininya wrote:
ok thanks!,
i guess i need to use a 2 pass,
so what settings work the best to get rid of blockiness,
and have a great picture, but not having the avg movie go above 2 cds?
thats all i ask.
so i need to know the settings for
avg br
max br
min br
and any other good twaeks or methods you guys find great results with.

thanks again, you guys really make some good points.

</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR size=1 color=black></TD></TR></TABLE>

Using TMPGEnc, I've been using 2 Pass, 0 MIN, ***AVG, 2400 MAX bitrate for Non-Standard VCD's (MPEG-1). "***" is whatever bitrate average you need to fit on a CD (use the VCD Help calculator, pick XVCD) Also tweak the audio bitrate down.

"Detect Scene Change" OFF, "No Motion Search per half Pel" either on or off (I usually can't tell the difference either way.

This gets me a very good result for most, if not all films. There is some blockiness, but you'll only notice most of it in very DARK scenes.

If you have a standard TV (19" to 25&quot, and you leave the "Sharpness" down a bit, this looks pretty much like a brand new VHS tape at 4-6 feet away. Except better when you pause it!

Supposedly Cinemacraft Encoder is even better at MPEG-1 VBR also, I'm still trying to perfect that one!

Hope this helps..

[shochan]

<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 2001-07-24 20:21:22, poopyhead wrote:
shochan, heh...

i personally think 2 pass vbr is a waste of time...just like using highest quality (slowest) rather than high quality (slow) for motion search accuracy...

unless u can spend twice as much time to encode, then knock yourself out w/ the 2 pass....otherwise....vbr with a pretty high cq setting is good for the encoding time...2 pass is especially long when encoding at higher bitrates
</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR size=1 color=black></TD></TR></TABLE>

Well if you feel that way ok... But the fact of the matter despite time (start encoding when you go to sleep), is that 2pass VBR is far better than any other mpeg 2 option in TMPGEnc.

<font size=-1>[ This Message was edited by: shochan on 2001-07-26 15:12:30 ]</font>