colormatrix

How to deal with ColorMatrix overflows?

Before I start here, I am using C#. I would like to do some transforms using the ColorMatrix class. The problem is that sometimes an overflow occurs for r, g, or b. Instead of clamping the value at 255, the matrix loops around and starts again at 0. This means that, for images which should appear all white, they begin to turn black a...

Rotate Hue using ImageAttributes in C#

How can I rotate the hue of an image using GDI+'s ImageAttributes (and presumably ColorMatrix)? Note that I want to rotate the hue, not tint the image. EDIT: By rotating the hue, I mean that each color in the image should be shifted to a different color, as opposed to making the entire image a shade of one color. For example, Origina...

How can we use the colormatrix only a part of image rather than whole image?

I know the use of colormatrix. but this work on the whole image. is there any way to work with colormatrix only a part of image rather than whole image. eg i want to give the brightness of only border area of image. i am working with c#. ...

Apply a ColorMatrix making use of GPU

I have a C# application that recolors an image using ColorMatrix. I understand that ColorMatrix doesn't make use of the GPU. What would be the best avenue to explore if I wanted to use the GPU to recolor the image? Pointers to where look in any suggested libraries would be appreciated, examples even more so! ...

How to continuously fade a BitmapData to a certain color?

I'm drawing stuff on a bitmapData and I need to continuously fade every pixel to 0x808080 while still drawing (its for a DisplacementMapFilter)... I think this illustrates my problem: http://www.ventdaval.com/lab/grey.swf The simpler approach I tried was drawing a semi-transparent grey box on it, but it never reaches a single color (i....

finding matrix through optimisation

I am looking for algorithm to solve the following problem : I have two sets of vectors, and I want to find the matrix that best approximate the transformation from the input vectors to the output vectors. vectors are 3x1, so matrix is 3x3. This is the general problem. My particular problem is I have a set of RGB colors, and another se...

Strange behaviour when appying a ColorMatrix to an image in .Net, WinForms.

The method below, takes a colour matrix and applies it to the supplied image. There are a couple of things to note: (1) It is not a function (2) The same image is used to create the graphics object, and as the source of the DrawImage method. Public Sub ApplyMatrixToImage(ByVal matrix As ColorMatrix, ByVal image As Image) Using atts...

iPhone documentation image transformation

Hi, I would like to know if there is a programming guide or other documentation for image transformation (histogram, matrix black & white, etc ...). ...

What would be a good TRUE black and white colormatrix?

I want to convert an image from color to B/W (i.e. no grayscale, just black and white). Does anyone have a good colormatrix to achieve this? ...

Any good source of explanatory documentation on ColorMatrix?

I'd like to try using ColorMatrix, but am only able to find examples that convert an image to grayscale. And even then, they tend to be presented as a chunk of 'magic numbers' code with no explanation. Does anyone know of a 'tutorial' on how to use ColorMatrix? For example I'd be interested in converting a grayscale image to a color ima...

How to Use Calculated Color Values with ColorMatrix?

I am changing color values of each pixel in an image based on a calculation. The problem is that this takes over 5 seconds on my machine with a 1000x1333 image and I'm looking for a way to optimize it to be much faster. I think ColorMatrix may be an option, but I'm having a difficult time figure out how I would get a set of pixel RGB va...

Required Info to choose colormatrix for getting original Image

Hi, I have a requirement where i need to mask and clear the masked portion of the images. I am done with masking part of the requirement. I am using color matrix to mask my image also the selected portion in the image is blacked out. For this the color matrix setting used is , colormatrix obj = new colormatrix ( { 255,0,0,0,0} {0,255,...