Histogram: Red & green swapped?

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AloisMuc

Histogram: Red & green swapped?

Post by AloisMuc »

The green and red graph are mixed up. The red channel has a green line, the green channel a red line. Blue is correct.

I compared the histogram with the D200 camera histogram, and the histogram of Corel PaintshopPro Photo XI. Both histograms are contrarily to XnView.

My Version of XnView is 1.90.2.
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helmut
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Post by helmut »

I've tried to verify this, surprisingly I find that it's not that easy to say. From my point of view, the whole histogram looks somehow screwed up and not alright.

A sample image which I've used:
Image
Last edited by helmut on Tue Feb 27, 2007 12:16 am, edited 2 times in total.
AloisMuc

Histogram: Red & green swapped?

Post by AloisMuc »

Helmut,

I took your example above an looked at the histogram in XnView: Blue is mainly on the right side of the panel, green mainly on the left side.
Took the same picture in other programs with histogram the colors blue and green are swapped: Green is dominant right and blue left.
marsh
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Post by marsh »

Helmut's sample image compared.
v.1.90.2 results:
Image

Gimp Results:
Image
nightflyer
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Post by nightflyer »

Here's another one:
Image
-=nightflyer=-
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xnview
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Re: Histogram: Red & green swapped?

Post by xnview »

AloisMuc wrote:The green and red graph are mixed up. The red channel has a green line, the green channel a red line. Blue is correct.

I compared the histogram with the D200 camera histogram, and the histogram of Corel PaintshopPro Photo XI. Both histograms are contrarily to XnView.

My Version of XnView is 1.90.2.
Right, there is a problem...
Pierre.
marsh
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Post by marsh »

v.1.90.3:
Image
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helmut
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Post by helmut »

marsh wrote:v.1.90.3:
From what I can see red, green, and blue are o.k., now. Not sure about grey.
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Post by nightflyer »

helmut wrote:
marsh wrote:v.1.90.3:
From what I can see red, green, and blue are o.k., now. Not sure about grey.
It looks OK. XnView presents composite luminosity histogram, while in my example it is RGB histogram.
If you mean spikes, your example has not ideal tonal ranges, take a tool that enables seeing Y Cb Cr components and you will see it.
-=nightflyer=-
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