What I've had difficulty with is getting my head around the fact that
this works at all with small integer values. But given that the data
originates with a gamma curve which is then linearized it must do so.
I've just had to accept the paragraph as written (whether Spanish or
English) :-)
Chuck Norcutt
On 6/16/2012 5:22 AM, Moose wrote:
> On 6/15/2012 7:00 AM, Chuck Norcutt wrote:
>> Very interesting but so far not understood. I'd never heard of a linear
>> histogram and I'll obviously have to study it much more.
>
> It's pretty simple. I assume you are familiar with the difference between a
> graph with linear vertical axis and one with
> a logarithmic axis. Not the same math, but a similar sort of effect.
>
>> So far I have not been able to make sense of this paragraph:
>>
>> "We must not think that the higher concentration of information due to
>> the linear development means we are losing tonal richness. This is not
>> like that at all, in fact a gamma corrected histogram starts from a
>> linear one to which a gamma correction curve has been applied and that
>> is why a lot of holes are created in the low end of gamma corrected
>> histograms. The tonal richness is not increased nor reduced for using
>> one or the other kind of image."
>
> Maybe it makes sense in the original Spanish?
>
>> The digital representation of the numbers constituting the tonal
>> information must be much different than what I would imagine looking at
>> figure 6.
>
> It has nothing to with 'digital'. Both figures 5& 6 are representations of
> exactly the same digital data. 6 is the data
> as it comes out of the sensor. 5 is the same data redistributed, via the
> gamma function, to look correct to human eyes.
> You've only ever seen histograms after gamma is applied.
>
> Non Linear Moose
>
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