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.

 

Go Back   Doom9's Forum > Video Encoding > New and alternative video codecs

Reply
 
Thread Tools Search this Thread Display Modes
Old 10th March 2011, 13:16   #1  |  Link
pbristow
Registered User
 
pbristow's Avatar
 
Join Date: Jun 2009
Location: UK
Posts: 262
Dummy codec for benchmarking purposes?

Has anyone produced a dummy or "null" codec, for benchmarking video tools such as AVIsynth and Virtualdub?

I often find myself wanting to compare the performance of several AVIsynth scripts, and wishing I could eliminate the encoding time of the codec from the process. My usual timing technique is to tell VirtualDub to encode either raw video or "Quality 1" DivX into an AVI file, and then use the "created" and "modified" timestamps of the file to tell me how long it took. However, sometimes the encoding time for DivX is significant compared to the execution time of the AVIsynth script (e.g. fairly simple scripts outputing Full HD video), and sometimes the disk i/o and space requirements of raw video are the problem. (Also DivX has annoying constraints on frame rate and file size - No good when you're trying to benchmark a script that puts out 1080p60!)

[EDIT - I've tried a variety of other codecs that seemed like they would be quicker: Most turn out to have annoying constraints of one kind or another.]

What would be really useful is a "null codec", that basically just discards all the frames that are fed to it except either the first or the last one, writes that one frame into the AVI file exactly as received, and then closes the file. Result: Encoding makes virtually zero contribution to the test time. [EDIT: And theoretically, no constraints at all on what framerates/sizes, colouspaces etc. can be fed to it.]

Has anyone done anything like this, or does any one fancy cobbling one together?

Last edited by pbristow; 10th March 2011 at 17:55. Reason: (Fixed a typo)
pbristow is offline   Reply With Quote
Old 10th March 2011, 14:11   #2  |  Link
J_Darnley
Registered User
 
J_Darnley's Avatar
 
Join Date: May 2006
Posts: 959
avsutil, ffmpeg's null output, mplayer's benchmark
__________________
x264 log explained || x264 deblocking how-to
preset -> tune -> user set options -> fast first pass -> profile -> level
Doom10 - Of course it's better, it's one more.
J_Darnley is offline   Reply With Quote
Old 10th March 2011, 14:54   #3  |  Link
Groucho2004
 
Groucho2004's Avatar
 
Join Date: Mar 2006
Posts: 3,896
I wrote a small cli tool for benchmarking purposes. You might want to try it: AVSInfo
Groucho2004 is offline   Reply With Quote
Reply

Tags
benchmarking, codec

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +1. The time now is 07:57.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2018, vBulletin Solutions Inc.