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-   -   KVCD: Large file sizes? (http://www.digitalfaq.com/archives/encode/175-kvcd-large-file.html)

zao 05-25-2002 12:59 PM

KVCD: Large file sizes?
 
i'm having trouble making files that will fit on one cd.

the steps i took are
1. ripped with smartripper
2. DVD2AVI - force film checked
3. FitCD - TemporalSmoother(2,2)
4. load .avs file and audio, load kvcd ntscfilm template.

is there something i missed? even a 93 minute movie was 850 meg. and it wasn't even an action movie - no explosions or flashy special effects. another was a 116 minute black and white movie. the file size ended up at 930 meg. these are examples but there have been a few more i have tried that ended up too big. none of them were 120 minutes.

if anyone has any suggestions let me know. i would appreciate it.

DaDe 05-25-2002 01:53 PM

Yes what happened to the purpose of this page? I have a 90 mins movie in 720 megs. I tought this page was intended to fit 2 hours of video into one 80 mins cd.

I dont mean to blame somebody but, understandme, a movie in two CD's with blocks in high action scenes, sounds closer to VCD and seems to leave the KVCD basics.

Just my opinion.

NYPlayer 05-25-2002 02:49 PM

I agree
 
The new template does not really encode 120 mins to 1 cd. The only movie I have gotten to encode is the Matrix, but with the old template this movie was about 500 meg.

I don't use the new template at all the size is very upredictable.

deltaboy 05-25-2002 03:19 PM

ya man! sorry to say KWAG, but i think the old template was a little more precise. i can safely go back to an 18 GOP with a 2300 max bitrate and 75 CQ, and still create marvelous results while keeping within the 800MB barrier.

no knocking KWAG and these outstanding templates tho. ive never found a better way to do my encodes.

kVCD all the way!!!

kwag 05-25-2002 03:33 PM

Something weird is going on here!

I did "The Matrix" with the old template, and the file size was 815MB.
And that's about 2 hours 14 minutes.

With the new template the size is 840MB, so I cut off about a minute and a half of the end credits.

This is all at 352x480 and via AviSynth with TemporalSmoother(2,2)

I also did "The others" and the size is about 600MB, for the complete movie, with the new template.

So under the same conditions, I am getting either the same file size, or around 20MB larger final size with the new template.

But the change in CQ from 70 to 80 is by far the best quality produced by the encoder, for the current parameters.

At CQ=70, the quality is good, but never even close to CQ=80.

kwag

rendalunit 05-25-2002 03:45 PM

I just put an 88 min movie (23.97 fps/ 4:3/ interlaced NTSC) onto an 80 min cdr with a little bit of overburn using the new template. I deinterlaced it with FeildDeinterlace() and used TemoralSmoother(2,2). The picture and sound quality is so good that you can barely tell the difference from the original dvd.

The Last Castle easily fit onto 1 cd with the old template and it's about 130 min. I'm going to try it again with the new template to see if it fits. Maybe letterboxed movies are a little smaller than 4:3?

Personally i'd rather get the best quality onto two cds because I can stack them into 1 jewel case. It really sucks when one of the cds of a movie gets lost! :(

kwag 05-25-2002 04:31 PM

I forgot to mention that I also did "Joy ride".
1 hour 37 minutes. That was 637MB.

kwag

zao 05-25-2002 04:40 PM

Quote:

Originally Posted by rendalunit
I just put an 88 min movie (23.97 fps/ 4:3/ interlaced NTSC) onto an 80 min cdr with a little bit of overburn using the new template.

thats pretty much my point. 88 min is a far cry from 120. personally i would rather fit my movies on one cd. if i wanted to use multiple discs i would encode with a different higher quality method.

i was dissapointed that i couldn't fit that 93 minute movie ("Made") on one disc. and i thought since the other was black and white ("The Man Who Wasn't There") that it might compress better. but like i said, maybe i am missing something. i have had success with the older templates, but the newer ones look better, and since kwag said there isn't much difference in file size, perhaps its something wrong with my settings. should i go back to the old template? if so where can i find it?

kwag 05-25-2002 04:46 PM

Quote:

Originally Posted by zao
Quote:

Originally Posted by rendalunit
I just put an 88 min movie (23.97 fps/ 4:3/ interlaced NTSC) onto an 80 min cdr with a little bit of overburn using the new template.

thats pretty much my point. 88 min is a far cry from 120. personally i would rather fit my movies on one cd. if i wanted to use multiple discs i would encode with a different higher quality method.

i was dissapointed that i couldn't fit that 93 minute movie ("Made") on one disc. and i thought since the other was black and white ("The Man Who Wasn't There") that it might compress better. but like i said, maybe i am missing something. i have had success with the older templates, but the newer ones look better, and since kwag said there isn't much difference in file size, perhaps its something wrong with my settings. should i go back to the old template? if so where can i find it?

If you want to go back to the old parameters, just drop the CQ from 80 to 70, change the GOP from 1-18-3-1-0 to 1-12-3-1-0 and change the audio back to "Joint Stereo" from "Dual Channel"

That's basically it.

kwag

NYPlayer 05-25-2002 05:00 PM

Template
 
I believe the bit rate has to change also not sure.

kwag 05-25-2002 05:01 PM

Re: Template
 
Quote:

Originally Posted by NYPlayer
I believe the bit rate has to change also not sure.

Oppps! Right NYPlayer!

Increase the bit rate from 1,450Kbps to 2,300Kbps.

Thanks,
kwag

deltaboy 05-26-2002 04:51 PM

lets compromise a bit then...

im working on the TRAINING DAY DVD right now. 122mins. my first encode, i used the old template:

CQ 75
max bitrate 2300
GOP 1-12-3-1-0

file size = 799MB.

came out great! looks awesome on a TV via standalone. when PC viewing, lacks detail with blurs and plenty edge interference. not a prob tho (im like 2 inches away from the monitor on full screen). dont know how itll look on a HDTV.

preparing for next encode, ill be using my own tweaked template:

CQ 78
max bitrate 2000
GOP 1-15-3-1-0
(any ideas on a more suitable GOP for this?)
file size = ill let you know tomorrow.

i guess ill also try the latest of KWAGs templates (dont like the low max bitrate, but it is necessary for comparision purposes). ill post my results tomorrow.

PS. do people prefer a closed GOP or an open one? how does this affect the file sizes? what about precision of I frames for chaptering purposes? i sometimes notice that the audio goes a bit wonky at times. seems to trail off when viewing.

zao 05-26-2002 07:25 PM

ok i just got done encoding "The man who wasn't there" again with the old template, but with dual channel selected. the final size came out at 650 mb. much better than 930 with the new template, but granted a lower quality picture. i definately think kvcd's are the way to go. i'll try messing around with it some more and see what i can come up with. and i think compromising between the two templates is a good idea. i'd like to see what others come up with.

kwag 05-26-2002 07:44 PM

Here's something new for everyone to try:

Run TMPEG and go to Settings/Video and besides Rate control (Constant Quality) go into "Setiings".
Change the P Picture spoilage from 0 to 18
Change the B Picture spoilage from 20 to 3

Now encode a couple of minutes and see if you get around 100KB file size savings per minute ( on average, specially on action scenes ) and the Quantization is lower ( means higher quality ) than with the current template.

I don't understand exactly the meaning of these fields, because the on-line help is not very helpfull. I think it was a Japanese to English translation, and it's not very well explained.

But I'm amazed at the results I got after encoding like with 50 different small clips of about 3 minutes each with different values.

If you look at the results with bit rate viewer ( http://www.tecoltd.com ) you'll see what I mean. With these new parameter changes, the Q level follows closer ( on average ) the bit rate. So it's producing a higher quality, but the final file size is a little smaller than with the P=0 B=20 8O

This has me puzzled, but it works :o
So give it a try, and if I get many positive results from many people, It'll be part of the template.

Try to be consistent with the test. Choose the same amount of frames from your movie. Make a test of at least a couple of minutes per clip, so you can see the difference.
The tests I made were done with the current template parameters:
GOP 1-18-3-1, Video MIN=300 MAX=1,450, CQ=80.

kwag

deltaboy 05-27-2002 12:57 PM

Quote:

Originally Posted by deltaboy
preparing for next encode, ill be using my own tweaked template:

CQ 78
max bitrate 2000
GOP 1-15-3-1-0
(any ideas on a more suitable GOP for this?)
file size = ill let you know tomorrow

k, files size comes out just a little larger at 820MB. i looked at the comparisons and found that blocking had increased by just a small margin, but overall, the picture looked far superior. more sharpness due to the higher CQ value of 78. so im assuming 77 would do it!

since KWAG has just posted his new template ( http://www.kvcd.net/forum/viewtopic.php?t=193 ), ill give that a try. id really like to see how the manual picture spoilage changes things up.

kwag 05-27-2002 02:01 PM

Quote:

Originally Posted by deltaboy
since KWAG has just posted his new template ( http://www.kvcd.net/forum/viewtopic.php?t=193 ), ill give that a try. id really like to see how the manual picture spoilage changes things up.

By setting both P and B in spoilage to zero, the Quantization is now closer to the bit rate, and the result is higher quality. As far as I could test with various runs, the quality is very close as with CQ=80, P=0 and B=20 in spoilage, as in the default TMPEG templates. This can be confirmed by running bitrate viewer and analyzing your mpeg files.
But the file size is not that much larger than the original CQ=70.

I'm re-encoding "The Matrix" :lol: again :lol: as I write this message, to check the file size. The quality is much higher than the original CQ=70 template.

Right now I'm at 65% done. Source position 1 hour 29 minutes and file size is 427MB. So I should end up with around 650MB with full end credits. It's looking very good. Have around 1 hour 30 minutes to go.

I'll post the final result when done.

kwag

kwag 05-27-2002 03:58 PM

Matrix done!
Result: 710,784KB :lol:
Average Q. Level viewed with bitrateviewer: 1.8 :lol: :lol:

kwag

zao 05-28-2002 08:41 PM

nice work man!

i tried encoding several clips and it is looking good so far. i'll start a new project soon and post results.

GFR 05-29-2002 07:54 AM

Hi Kwag

I was thinking about the mixed results with the "new" template.

If you looked at an ideal CQ encode in BitRate viewer, if you have the MAX bitrate high enough, the Q (quantization) should be a straight horizontal line while the bitrate varies (going down for "calm" scenes and up at "nervous" scenes.

This means that both low-action and high-action scenes will have the same "quality" (quantization level), and if you paused the video in a high action scene it would look as good (or as bad :)) as the low action scenes.

If the MAX bitrate is not high enough for a given Q setting, then at high motion scenes it will need to quantize more than the specified Q so as not to violate the max bitrate, hence the quantization curve will "follow" the bitrate at the bitrate peaks.

This means that the high action scenes will look "worse" than the low action scenes and if you pause you see the blocks. But, at high action scenes, the action itself will "MASK" the blocks and they may be hard to notice unless you pause the video. The overall visual impression may be hat the quality is the same for the whole film.

If you have a template with high Q - low MAX like the polemic "new" one, and encode a movie with low action most of the time, the higher Q will make the low action scenes look better (compared to low Q - high MAX as the original) but it will increase the average bitrate at these scenes. The bit rate at the peaks will be lower, but as the movie has not many peaks the overall average will be higher and the file size is bigger.

In a movie like "Matrix" you are hitting the ceiling almost all the time, so the lower MAX will help bring the overall average bitrate down altough the bitrate is higher for eventual low action scenes :). You may even get a smaller file size compared to the original.

Perhaps you could keep both templates and rename them to KVCD - high action / KVCD - low action :)

kwag 05-29-2002 11:05 AM

Hi GFR:

You are 100% right in all you say :)

The calculations for the CQ used is to favor the best quality from low motion to medium motion. That was my original intention. In high motion the CQ will degrade but the visual perception, as normally seen on a TV, doesn't see the loss effect. Just like in MP3' high frequencies are discarded and frequencies are discarded if they have another closer frequency with a higher ampliture ( x amount of decibels above ).

In the ideal Quantization, the CQ would be horizontal, as you say.
But I have never seen a perfect horizontal line with TMPEG in CQ mode!.
Even if I you increase the bit rate above saturation, say 8,000Kbps, and the CQ to 100.

At least with the current parameters and the new ones I'm playing now ( 704x480 ) 8)
sample here: http://www.kvcd.net/forum/viewtopic.php?t=205

But the problem with having dual templates is that most movies do have low action and high action. So what I did was to try and get a generic template that would accomodate most videos.

We'll see what develops in the future :wink:

Thanks,
kwag


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