For starters, I apologize for my English, I used google translate.
For some years that I give up trying to fix this bug which now describe.
It's Reading and Pixel Graphics.
I do not know if the bug is on the graphics or the reading of pixels.
The images describe the problem better.
1 - http://upperpix.com/pm-YSV8.html[^]
2 - http://upperpix.com/pm-QDA3.html[^]
The reading of pixels is done using an object created by me.
The 'object works fine, then incorrect values are not due to some incorrect completion of the object.
the position of "Mouse Y" is at 0 but the values I read one more.
If, however, change the first color of "LinearGradientBrush" and select an almost black color or a color with RGB values that are close to 0, the value is correct.
I do not know how to solve the problem, I wrote a series of forums but no one has been able to help me.
Thank you and I apologize for the English, I hope you understand something.