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. |
|
19th January 2017, 01:44 | #1 | Link |
Registered User
Join Date: Jan 2015
Posts: 1,056
|
XviD overshooting target file size
Is there anything, other than user error, that could cause a 2-pass XviD encode to exceed its intended file size? In particular, will it overshoot if the target file size is "too low" for the video's resolution, frame rate, and amount of motion? I just had to set the target amount of video data to 280 mb in order to get the actual amount of data down to ~310 mb (with audio adding another ~40 mb for a total file size of 350 mb).
__________________
I ask unusual questions but always give proper thanks to those who give correct and useful answers. Last edited by Katie Boundary; 19th January 2017 at 09:27. |
19th January 2017, 10:38 | #2 | Link |
HeartlessS Usurer
Join Date: Dec 2009
Location: Over the rainbow
Posts: 10,980
|
Dont know, but TmpGenc mpeg used to have a minimum bitrate that it would not go below (and would not tell you that it was going to ignore your settings).
(about 200kb/s I think, for mpeg)
__________________
I sometimes post sober. StainlessS@MediaFire ::: AND/OR ::: StainlessS@SendSpace "Some infinities are bigger than other infinities", but how many of them are infinitely bigger ??? |
17th February 2017, 15:08 | #10 | Link |
Unavailable
Join Date: Mar 2009
Location: offline
Posts: 1,480
|
|
19th February 2017, 23:13 | #12 | Link |
Join Date: Mar 2006
Location: Barcelona
Posts: 5,034
|
So why are you using such an inefficient encoder?
__________________
Groucho's Avisynth Stuff |
15th April 2017, 03:48 | #16 | Link |
Registered User
Join Date: Jan 2015
Posts: 1,056
|
1.3.4
I'm currently converting season 2 of Modern Family to VCD-compliant Mpeg-1, but once that's done, I'll dust off some of ye olde Andromeda or Birds of Prey scripts and see if changing the minimum quantizer from 1 to 2 has much of an effect.
__________________
I ask unusual questions but always give proper thanks to those who give correct and useful answers. |
15th April 2017, 09:59 | #17 | Link | |
Registered User
Join Date: May 2006
Posts: 3,997
|
Quote:
http://forum.doom9.org/showthread.ph...775#post787775 Looking forward to seeing your findings. |
|
17th April 2017, 15:09 | #20 | Link | |||
Registered User
Join Date: Mar 2011
Posts: 4,829
|
Katie probably won't read this post, or pretend not to, because I think I'm one of the "other forum members" she refers to in her signature which means I'm on her ignore list so I can't learn from her reading my posts..... or however it works according to her signature...... but...
she probably should try what I did here and run a CQ2.0 single pass encode to see what the resulting bitrate will be, and whether it's in the same ballpark as the bitrate she's using for 2 pass encoding. Or she could at least run a compression test. I'd explain how to run one but I probably haven't got it wrong enough to learn how.... or however it works according to her signature..... but it's just guessing without any further details. I played around a little more with the sample I'd been using for testing a couple of days ago, and this time Xvid wasn't overshooting the requested bitrate. After hunting through log files to see WTF, it turned out I somehow reset the overflow percentage. I don't remember doing that, but with it increased to 10% again today the target bitrate was almost exact. Highlights from yesterday's log file: Quote:
Quote:
Out of curiosity, I tried the same encode using AutoGK and Xvid 1.2.1. AutoGK wasn't happy about the bitrate. Quote:
AutoGK doesn't set the min quantizer to 1. Instead, when the quality is high, it actually does this (for lower quality it might reduce the min and max to 2 and 4 respectively etc.).... Would the following really force the same quantizer for all frames (assuming B-Frames were still enabled)? Last edited by hello_hello; 17th April 2017 at 15:11. |
|||
Thread Tools | Search this Thread |
Display Modes | |
|
|