[theora] Why Our Civilization's Video Art and Culture is Threatened by the MPEG-LA

[fboehm]

Hi,

I am interested in some sort of open source surveillance camera for the 
masses with ethernet, megapixel resolution, wideangle lens, and weather 
resistance. It's not the same application you discussed but it could 
perhaps fit together with this project.

What are you thinking?

Regards,
Franz


Am 2010-05-06 06:44, schrieb Basil Mohamed Gohar:
> On 05/05/2010 10:42 AM, Basil Mohamed Gohar wrote:
>    
>> On 05/05/2010 10:09 AM, Lino Mastrodomenico wrote:
>>
>>      
>>> 2010/5/4 Basil Mohamed Gohar<abu_hurayrah at hidayahonline.org>:
>>>
>>>
>>>        
>>>> At acceptable bitrates,
>>>> e.g., 25Mbps+, at HD resolutions, MJPEG with a good quality encoder does
>>>> not look significantly worse than other, more modern codecs
>>>>
>>>>
>>>>          
>>> I'm completely out of my depth here, but isn't 25 Mbps at 1920x1080
>>> and, say, 25 fps only 0.5 bits per pixel? For low complexity scenes
>>> that's enough for a pretty good-looking quality, but not even close to
>>> the near-losslessness that some people expect from a camcorder.
>>>
>>> And for high-complexity videos that's awfully too low (remember it's
>>> only 125 kBytes per frame). Try e.g. compressing this image (with lots
>>> of small details like the hair and the dress) down to a 125 kB JPEG:
>>>
>>>      http://www.mastrodomenico.eu/images/dichen.png
>>>
>>> Again I'm not and expert in the field, but I would expect that for
>>> very good quality in worst-case scenarios a 1080p 4:2:0 MJPEG stream
>>> may need 100-150 Mbps or even more, and a good denoising filter before
>>> the compression.
>>>
>>>
>>>        
>> I did some informal testing with some HD content I've made myself, and
>> 25Mbps for MJPEG wouldn't really cut it.  We'd need closer to 50Mbps to
>> get something acceptable, but yeah, I think I overestimated MJPEG's
>> suitability at these rates.
>>
>>      
>>>
>>>
>>>        
>>>> I thought about keyframe-only Theora, but then, if we're going
>>>> to do that, why not just fall back to MJPEG?
>>>>
>>>>
>>>>          
>>> One reason is that if you use Theora you can offer to the user the
>>> option to switch to a full intra+inter stream with dramatically lower
>>> bitrates. Plus doesn't MJPEG have a lower quality than intra-only
>>> Theora?
>>>
>>>
>>>
>>>        
>> Well, now we're talking many different things!  If we want intra-only,
>> such as DiracPro or MJPEG, then intra-only Theora is a possible player,
>> but having the ability to switch up to full intra+inter Theora will add
>> the full complexity of the spec, so why bother with the inefficiency of
>> intra-only anyway?
>>
>> The way I see it, if we're going to go for a freedom-friendly camcorder,
>> we can have the option of supporting more than one codec (at least on a
>> technical level).  Whatever hardware can do intra-only Theora, I'm
>> reasonably confident can also do MJPEG as well.
>>
>> Having said that, as I mentioned elsewhere, I'm going to play-around
>> with some intra-only Theora and see how it performs vis-a-vis MJPEG.
>>
>>      
> I've done some more casual testing of intra-only Theora, and ptalarbvorm
> really has some beautiful intra-only video, even at a measly 25Mbps!  I
> am pulling down some 1080p clips from media.xiph.org right now to test
> some more with, and I will let you guys know the results later.
>
> Maybe we can call it TheoraPro...;)
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