>On Apr 3, 6:25=A0am, "praveen.264" <kpk_...@yahoo.co.in> wrote:
>> Hi friends !
>>
>> Iam trying to project the performance of our video processin
algorithm
>> objectively in terms of PSNR and SSIM. We are dealing with YV12 videos
I=
>am
>> using the MSU Video Quality measurement tool to compute the PSNR an
SSIM
>> values. Here they give the options to compute the values fo
Y-componet
>> alone (and average for all the Y frames), U componet alone (and averag
f=
>or
>> all the U frames),V componet alone (and average for all the V frames.
>>
>> My question here is which value should I take into consideration (Y,
or
>> V?? or the average of Y,U,V values??) for comparing with unprocesse
vide=
>o?
>>
>> to summarize,
>>
>> what will be correct PSNR for a YUV video - =A0Y component PSNR,
compon=
>ent
>> PSNR or V component PSNR or the average of the three?
>>
>> Pls give ur valuable inputs..
>>
>> Thanks in advance,
>> Praveen
>
>There is no one answer that is "correct". I have seen much literature
>in the video compression community where the Y PSNR is the primary
>metric, and the others are ignored, or assumed to follow fairly
>closely. If you wanted conservative results, you could use max of
>Y,U,V. But there's certainly no reason you can't average them either.
>If on the other hand you're try to compare against some other
>published literature, you should do exactly what they do to make the
>comparison more fair.
>
> - Kenn
>

Hi Kenn!

I was caught in this dilemma because of the following situation:

Our processing is mainly concentrated on Y component than U and
components. So, obviously as the U and V components are not much affected
the PSNR or SSIM for U and V will be very high compared to the Y component
Consider the follwoing example:

I have to compare our encoder with an existing encoder (MPEG4 or H.26
etc..) which gave the following PSNR values (compared with original file
for Y, U, and V respectively: 49, 53, 54 => Avg of YUV = 52 db (only thi
Avg value being shown in the literature without the individual values)

let the values obtained by our encoder (compared with original file) be
51, 80, 80=> Avg. of YUV = 70.33

now, going by the Avg., can we claim a whopping difference of 18.33 d
while the actual improvement is 2 db for Y-component alone?