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. |
28th March 2002, 08:32 | #1 | Link |
Half Dome - Come and see!
Join Date: Dec 2001
Location: CA
Posts: 227
|
Gnot calculate 1.6GB, DivX5 Pro makes 1.1GB
hi,
it's strange! Gknot tells me that my video (without audio) will 1,6GB but in the end after encoding with VD it is just 1,1 GB. Failure?
__________________
cu yose Yosemite National Park, CA - The greatest place on earth |
28th March 2002, 10:10 | #3 | Link |
Half Dome - Come and see!
Join Date: Dec 2001
Location: CA
Posts: 227
|
sure, but how can I know which bitrate I should take?
in worst case, my movie is in the end much bigger than wished... or is there something I can say: 100 kbps (video-bitrate) more or 100MB more, too?
__________________
cu yose Yosemite National Park, CA - The greatest place on earth |
28th March 2002, 12:24 | #4 | Link |
asleep for far too long
Join Date: Oct 2001
Posts: 131
|
i've found that setting a higher bitrate will make the codec less predictable. try increasing the resolution instead, if you're off by about 500Mb, increase resolution until the total pixels per frame goes up by 20-30%. give it a shot, it might work
|
28th March 2002, 15:46 | #5 | Link |
Piper at theGates of Dawn
Join Date: Nov 2001
Posts: 2,136
|
I think if you can't reach the desired size with a bitrate x, even increasing x to 10000 wouldn't help to make the final file bigger. Maximum quality was reached, so all you can do is increase the resolution, avoid any filters and use sharp bicubic resizing.
|
28th March 2002, 22:38 | #6 | Link |
Registered User
Join Date: Dec 2001
Location: Portugal
Posts: 730
|
What we need is some kind of comp check using divx5. Jonny has made a thread about this, and i too made some tests using his directions.
You can read it here : http://forum.doom9.org/showthread.php?s=&threadid=19927
__________________
Rui |
29th March 2002, 00:52 | #7 | Link |
DivX.com Mod Squad
Join Date: Jan 2002
Posts: 370
|
Hi,
If you want a totally predictable encode using DivX 5 Pro, turn off b-frames. Most of the time this is what was causing your problems. In the smaller number of cases where the max quality is reached, you are out of luck. Use ac3 audio, extra audio tracks, etc... to fill in extra space. dragoman |
29th March 2002, 05:36 | #8 | Link | |
Registered User
Join Date: Mar 2002
Location: Québec, Canada
Posts: 47
|
Quote:
|
|
29th March 2002, 08:55 | #9 | Link |
Registered User
Join Date: Oct 2001
Location: Croatia
Posts: 190
|
As I understand, B-frame is compressed more then P frame (delta frame) , so B frame is for use if you want smaller file size with same bitrate . Video quality is equal in both cases (or maybe better without B-frame). Yosemite didn't say what he was using but I guess it was 2pass not 1pass-qulity .
I must agree with dragoman . Turn off B-frame ,and if that don't help try using Divx4Log prog. to edit log from 1st pass and change quantizer . FFS P.S. I'm not sure is B-frame simply better compressed or it's used higher quantizer ?! Sorry , I wrote this P.S. before I saw dragoman’s post and –h’s replay about same thing. (Sorry for my bad english , but I'm geting better ) Last edited by ffroms; 29th March 2002 at 09:45. |
29th March 2002, 09:50 | #11 | Link |
Registered User
Join Date: Oct 2001
Location: Croatia
Posts: 190
|
1pass quality is better 'couse it don't use bitrate but fixed quantizer (compression) and all frames are compressed same. Of course there is still question about B-frame (it's compressed 2x then other frames) so I guess it's better without B frame but you can expect higher file size.
When you were doing 2pass encoding did you change mQ and MQ (by default it's 2 and 12) ? Try to set them both to 2. That way you will have fixed quantizer. FFS Last edited by ffroms; 29th March 2002 at 09:59. |
29th March 2002, 10:51 | #12 | Link |
Encoding Dinosaur!
Join Date: Oct 2001
Location: Europe
Posts: 1,668
|
I don't use the PRO version of DivX5. I use the normal version and it's 100% predictable. When you get an undersized movie, that means that it is already saturated, no matter how much you make the bitrate higher, it won't get any bigger. If you wanna a bigger size, you gotta higher the resolution.
@ffroms setting both quantizers to 2 is equivalent to quality based 100% IT's USELESS & TIME WASTING then to use 2-pass encoding! |
29th March 2002, 11:40 | #13 | Link |
Registered User
Join Date: Oct 2001
Location: Croatia
Posts: 190
|
I'm new at divx so correct me if I'm wrong.
Here what I think. Let say you set bitrate at 1000kbps and both quant at 2 (in 2pass) . This will give you file with fixed quant but codec will try to stay close to given bitrate. If you try to do same movie with 1pass-quality and quant at 2 will give file with only compression at 2 without thinking about bitrate so you probably end with bigger file. There is still matter with B-Frame. FFS |
29th March 2002, 14:33 | #16 | Link |
DivX.com Mod Squad
Join Date: Jan 2002
Posts: 370
|
@tripnotik
Yes, I know exactly what turning b-frames off would do, however he was asking how to get a predictable filesize. Turning off b-frames is the only way to do this in DivX 5 Pro @ffroms How do you know that the codec doubles the quantizer for b-frames? Where did you get this information? @bobonts Yes, you are correct if you want the best quality, but your filesize will be very large and you cannot predict it. dragoman |
29th March 2002, 15:39 | #18 | Link |
Registered User
Join Date: Feb 2002
Location: Italy
Posts: 876
|
If you don't want to go undersized:
1) Use compressibility test: http://forum.doom9.org/showthread.php?s=&threadid=19927 2) If you get more that 80% you'll probably get undersized avi... so try to increase the resolution or decrease number of cds or play with bicubic methods 3) If you get 95%-100% or >100% you can go with a costant quality encoding with quantizers = 2 (without changing setting) |
29th March 2002, 21:08 | #19 | Link | |
Piper at theGates of Dawn
Join Date: Nov 2001
Posts: 2,136
|
Quote:
|
|
30th March 2002, 05:16 | #20 | Link |
DivX.com Mod Squad
Join Date: Jan 2002
Posts: 370
|
@bob - thanks for the thread reference....just proves I am right in what I said
@theReal You are correct sir, I should have said "only way to do this 100% of the time" - if you are using b-frames and the quality is maxed, then it doesn't work. dragoman |
|
|