[theora] Sampling encoder timings between libtheora-1.0 & libtheora-1.1beta3

Basil Mohamed Gohar abu_hurayrah at hidayahonline.org
Sun Aug 30 07:54:53 PDT 2009


On 08/30/2009 09:24 PM, Bernard Jungen wrote:
> On Sun, Aug 30, 2009 at 10:11:59AM +0800, Basil Mohamed Gohar wrote:
>   
>>    1. planet-earth-360x240.yuv4mpeg - A clip from the Discovery/BBC
>>       series Planet Earth from DVD 1, the "Mountains" chapter - the
>>       first 5000 frames (I dropped half the fields to get non-interlaced
>>       video, then rescaled)
>>     
> You can properly deinterlace the clip with e.g. the yadif or pp=lb filters of
> mplayer/mencoder.
>   
I'm not as well-versed in mencoder as I am FFmpeg, so I guess that's why
I went the convoluted route.
>   
>> All clips were converted to yuv4mpeg format and then copied to /dev/shm
>> to remove, as much as possible, any potential outside influences on
>> encoder performance.
>>     
> It's not necessary to use /dev/shm on Linux if you use the time command.
>
> It's also possible to separate conversion to yuv4mpeg and theora compression
> into separate processes. Just time the theora compression process then. No
> problem.
>   
That's a great suggestion.  I re-read the manpage for `time`, and I
realized I reported the wrong times - I was reporting the *real* time,
and I should have reported user + kernel.  The difference is minor,
given my testing methodology, but it exists.
>   
>>  Also, no sound
>> was included, thus limiting this test solely to Theora encoding.
>>     
> Good. I think that's what we want.
>
>   
>> All tests were run under Fedora 11, 32 bit, booted into single user mode
>> [4].
>>     
> Again, it's not necessary to do the tests in single user mode on Linux if you
> use the time command.
>
>   
>> If there's a lot of interest in this testing methodology, I might put
>> together some scripts to make automating, timing, & reporting more
>> systematic.  These runs were all basically done manually on the
>> command-line.  I even hand-wrote the results down.  ;)
>>     
> Of course there is interest. Go ahead. It will make testing of different files,
> processors and compressor settings and versions by different people much more
> easier. Even the simple fact that you'll probably have to do some more tests
> will justify scripting!
>
> Thank you.
>
> Bernard.
>   
The only problem with the scripting is that I am most likely to do it in
PHP!  I might give a try to doing it in bash, especially since I know
how to use the `time` command more properly now.

-- 
      Basil Mohamed Gohar
abu_hurayrah at hidayahonline.org
http://www.basilgohar.com/blog
basilgohar on irc.freenode.net
GPG Key Fingerprint:  5AF4B362



More information about the theora mailing list