Coming in very late on thread....

sequences need to be grouped in multiple dimensions. I'd suggest that
one dimension be:

- Talking heads (still camera, little movement)
- Cinematic material (slow camera moves, dramatic cuts, sudden moves)
- Amateur video (camera shake, sudden moves)
- Artificially generated (no camera shake, color gradients smoother than
normal, no inter-frame movement blur)

Another dimension should be available bandwidth

- 0.1 Mbits, 1 Mbits, 10 Mbits, 100 Mbits

I've come to the conclusion that varying resolution should be considered
one tool for achieving lossy compression, and should not be a primary
dimension - YMMV.
(that said, existing source material has resolutions, and a codec should
make sure to handle all resolutions well.)

A third dimension should be available computing resources for encode and
decode:

- Infinite encode resources available (test style)
- Encode 10x slower than real time (production environments)
- Encode faster than real time (interactive + overhead)

- Decode in real time, stalls acceptable
- Decode in real time, stalls not acceptable

A fourth dimension is about the use of lookahead:

- Any lookahead, including multipass, is acceptable
- Lookahead of a second or two is acceptable
- Lookahead of 100 ms is acceptable
- No lookahead at all is permissible (minimum delay)

I'm running some codec comparisons on compare-codecs.appspot.com (open
source project) - incorporating Derf's clip set is high on my TODO list.

Den 27. jan. 2015 10:17, skrev Mo Zanaty (mzanaty):
> Since a particularly interesting comparison will be HEVC, should we
> consider some JCT-VC standard sequences and operating points?
> 
> We can redefine the classes of sequences to be the most relevant for
> initial experiments. For example:
> 
> Class 1: Video Conferencing
>   a) 360p 30Hz 0.1-1Mbps
>   b) 720p 30Hz 0.2-2Mbps
>   c) 720p 60Hz 0.3-3Mbps
>   d) 1080p 30Hz 0.4-4Mbps
>   e) 1080p 60Hz 0.6-6Mbps
>   f) 2160p 30Hz 1.2-12Mbps
> 
> Class 2: Video Streaming
>   a) 360p 30Hz 0.2-2Mbps
>   b) 720p 30Hz 0.3-3Mbps
>   c) 1080p 24Hz 0.6-6Mbps
>   d) 2160p 24Hz 2-20Mbps
> 
> 1b and 2c may be the most interesting operating points for many.
> 
> We can also consider other classes like professional applications, screen
> content / wireless display, etc. with relatively higher rates.
> 
> 
> Mo
> 
> 
> On 1/26/15, 8:09 PM, Monty Montgomery <[email protected]> wrote:
> 
> Right, and our use of AWCY and test clips being mostly regression
> testing at the moment (and specific to our particular glass box), I
> wasn't proposing the particulars what we're doing right now as the
> starting point.  Rather, it could be, but used a different way, not as
> we're using it.
> 
> Monty
> 
> On Sun, Jan 25, 2015 at 1:14 PM, Eric Rescorla <[email protected]> wrote:
>> Following up to myself: what i'm hoping here is to get a consensus list
>> of
>> the domains of interest so that we can then evaluate our progress against
>> them.
>>
>> -Ekr
>>
>>
>> On Sun, Jan 25, 2015 at 12:57 PM, Eric Rescorla <[email protected]> wrote:
>>>
>>>
>>> On Fri, Jan 23, 2015 at 1:45 PM, Monty Montgomery <[email protected]>
>>> wrote:
>>>>
>>>> Hi everyone,
>>>>
>>>> Testing discussions are already happening in private and elsewhere.
>>>> The basic points are usually pretty similar and I expect they're going
>>>> to keep coming up, so I'm going to try centralizing it here.
>>>>
>>>> The Daala team is using a small number of fairly short test sequences
>>>> in an automated testing system ('Are We compressed Yet?) mostly as a
>>>> way of doing regression testing.  It's also used to sanity check small
>>>> improvements that are unlikely to be apparent in visual testing.  The
>>>> various graphs we've shown in demos and the like are coming from AWCY.
>>>>
>>>> One point that's been raised several times is that we're not testing
>>>> reasonable or practical bitrates.  Or, rather, that our range includes
>>>> the typical useful rates, but we also go way up to insanely high rates
>>>> no one would ever use.  That's mainly because AWCY is meant as a
>>>> sanity/regression check, and many subtle bugs we've had in the past
>>>> have only popped out at near-lossless quality levels.  Automated
>>>> testing should report these rates, but we don't intend to use them in
>>>> evaluation of relative practical performance.
>>>
>>>
>>> To sharpen this point a little bit, it's probably useful to distinguish
>>> between testing for performance evaluation and testing for regression,
>>> continuous integration etc.
>>>
>>> For the purpose of continuous integration, we should, as you
>>> suggest, test all sorts of parameter sets, including insane ones,
>>> as well as how the decoder handles bogus encodings, etc. For
>>> the purpose of performance evaluation/comparison, I would suggest
>>> that it would be useful to try to define a set of strawman scenarios
>>> which we would use. I'm sure others have different opinions, but
>>> for me the scenarios of most interest are basically videoconferencing,
>>> so roughly speaking:
>>>
>>> - Some set of sizes like:
>>>   - QCIF
>>>   - VGA
>>>   - 1080p
>>>
>>> - 30fps.
>>> - Bit rates on the order of 200kps - 5ish Mbps, depending on the size
>>> (I could be a bit off here).
>>>
>>>
>>> Presumably we want some streaming use cases, but I have a less good
>>> handle on what typical streaming is...
>>>
>>> -Ekr
>>>
>>>
>>>
>>>
>>>
>>>
>>>> Another point that keeps coming up is that we should come up with a
>>>> standard set of sequences and rates for trading and evaluating first-
>>>> and probably second-line evaluations.  Full agreement there, though
>>>> our own frontline tetsing right now is only using a handful of clips
>>>> of a few seconds each (though our available library is much larger).
>>>>
>>>> Monty
>>>>
>>>> _______________________________________________
>>>> video-codec mailing list
>>>> [email protected]
>>>> https://www.ietf.org/mailman/listinfo/video-codec
>>>
>>>
>>
> 
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