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use vtkUnsignedCharArray import byte[]

I don't understand why a column of pixels on the right is moved to the left, and there is also a problem with the imported colors
This is My code
private void RendervtkImageImportBmp2()
{
var myBitMap = new Bitmap(bmpPath);
byte[] bmpBytes = BmpHelper.BitmapToByte(myBitMap);
GCHandle hObject = GCHandle.Alloc(bmpBytes, GCHandleType.Pinned);
var bmpInptr = hObject.AddrOfPinnedObject();
vtkImageImport imageImport = new vtkImageImport();
imageImport.SetDataSpacing(1, 1, 0);
imageImport.SetDataOrigin(0, 0, 0);
imageImport.SetWholeExtent(0, MyBitMap.Width - 1, 0, MyBitMap.Height - 1, 0, 0);
imageImport.SetDataExtentToWholeExtent();
imageImport.SetDataScalarTypeToUnsignedChar();
imageImport.SetNumberOfScalarComponents(3);
imageImport.SetImportVoidPointer(bmpInptr);
imageImport.Update();
var actor = new vtkImageActor();
actor.SetInput(imageImport.GetOutput());
var ren = new vtkRenderer();
ren.AddActor(actor);
var renWin = new vtkRenderWindow();
renWin.SetParentId(this.Handle);
renWin.SetSize((this.Width - (this.Width / 2)), this.Height);
renWin.SetPosition(0, 0);
renWin.AddRenderer(ren);
renWin.Render();
}
pictures show the result
this is afterimport picture
this is original image
I'm just getting started with VTK, please help me to see where I made a mistake, thank you

Replacing colour of an Image

I am trying to replace the black colours of a picture with white, and vice versa. This is actually so my OCR code can read it on white backgrounds better. It's currently getting the image from clipboard
Image img = Clipboard.GetImage();
pictureBox1.SizeMode = PictureBoxSizeMode.StretchImage;
pictureBox1.Image = img;
I've seen some other questions where they're working with an actual bitmap, but how do I approach it direct from Clipboard?

Another solution using the ColorMatrix class.
You can use the Graphics.DrawImage overload that accepts an ImageAttributes argument.
ImageAttributes.SetColorMatrix() sets the color-adjustment matrix, optionally targeting a specific category (Bitmap, Pen, Brush etc.) and can be instructed to skip the Gray Colors, modify the Gray colors only or all Colors.
The ImageAttributes.SetThreshold() method allows to regulate the Colors cutoff point (threshold) to fine tune the Brightness.
It accepts values from 0 to 1.
When set to 0, an image is all white, all black when set to 1 (see the Docs about it).
Also consider that the "Inversion" depends on the original bitmap color pattern, so try different approaches. Sometimes, inverting the brightness can give you a better result, sometime it doesn't.
You OCR must be "trained", to verify what values suits it better.
Take a look at these articles:
Recoloring (MSDN)
ASCII Art Generator (CodeProject)
Brightness Matrix:
R=Red G=Green B=Blue A=Alpha Channel W=White (Brightness)
Modify the Brightness component to obtain an "Inversion"
R G B A W
R [1 0 0 0 0]
G [0 1 0 0 0]
B [0 0 1 0 0]
A [0 0 0 1 0]
W [b b b 0 1] <= Brightness
using System.Drawing;
using System.Drawing.Imaging;
// ...
Image colorImage = Clipboard.GetImage();
// Default values, no inversion, no threshold adjustment
var bmpBlackWhite = BitmapToBlackAndWhite(colorImage);
// Inverted, use threshold adjustment set to .75f
var bmpBlackWhite = BitmapToBlackAndWhite(colorImage, true, true, .75f);
// ...
private Bitmap BitmapToBlackAndWhite(Image image, bool invert = false, bool useThreshold = false, float threshold = .5f)
{
var mxBlackWhiteInverted = new float[][]
{
new float[] { -1, -1, -1, 0, 0},
new float[] { -1, -1, -1, 0, 0},
new float[] { -1, -1, -1, 0, 0},
new float[] { 0, 0, 0, 1, 0},
new float[] { 1, 1, 1, 0, 1}
};
var mxBlackWhite = new float[][]
{
new float[] { 1, 1, 1, 0, 0},
new float[] { 1, 1, 1, 0, 0},
new float[] { 1, 1, 1, 0, 0},
new float[] { 0, 0, 0, 1, 0},
new float[] {-1, -1, -1, 0, 1}
};
var bitmap = new Bitmap(image.Width, image.Height);
using (var g = Graphics.FromImage(bitmap))
using (var attributes = new ImageAttributes()) {
attributes.SetColorMatrix(new ColorMatrix(invert ? mxBlackWhiteInverted : mxBlackWhite));
// Adjust the threshold as needed
if (useThreshold) attributes.SetThreshold(threshold);
var rect = new Rectangle(Point.Empty, image.Size);
g.DrawImage(image, rect, 0, 0, image.Width, image.Height, GraphicsUnit.Pixel, attributes);
return bitmap;
}
}

You can use the ColorMap and ImageAttributes classes from the System.Drawimg.Imaging namespace to directly replace the pixels in your image:
Image img = Clipboard.GetImage();
if (img != null) {
ColorMap[] cm = new ColorMap[1];
cm[0] = new ColorMap();
cm[0].OldColor = Color.Black;
cm[0].NewColor = Color.White;
ImageAttributes ia = new ImageAttributes();
ia.SetRemapTable(cm);
using (Graphics g = Graphics.FromImage(img)) {
g.DrawImage(img, new Rectangle(Point.Empty, img.Size), 0, 0, img.Width, img.Height,
GraphicsUnit.Pixel, ia);
}
pictureBox1.SizeMode = PictureBoxSizeMode.StretchImage;
pictureBox1.Image = img;
}

if your image is B&W, it is very easy in OpenCV:
// bmp is your bitmap
var inverted = (255 - bitmap.ToMat()).ToMat().
.ToBitamp() // or
.ToWriteableBitmap() // or
.ToBitmapSource()
OpenCV can be a little overkill if this in your only manipulation in the whole app

Convert grayscale partially transparent image to a single color in c#

I am trying to create a function that takes a gray scale image and a color and colors the gray scale image using that color shade but keeps the shading levels of the gray scale image. The function also should not color the transparent parts of the image. I have multiple layers (multiple png's) I will be combining later and only need to color certain layers. I have looked around and found similar things but not quite what I need. I know how to do it in HTML5 on front end for the user using Canvas but I need a way to achieve same thing on the backend using I am guessing either a manual method using unlocked bitmap memory calls or a ColorMatrix class. Can anyone help me, graphics aren't my strongest area but I am slowly learning. See the function below for what I need in C# that I did in javascript. Doing the hidden canvas stuff isn't as important because I am doing this server side for saving to PNG file...
function drawImage(imageObj, color) {
var hidden_canvas = document.createElement("canvas");
hidden_canvas.width = imageObj.width;
hidden_canvas.height = imageObj.height;
var hidden_context = hidden_canvas.getContext("2d");
// draw the image on the hidden canvas
hidden_context.drawImage(imageObj, 0, 0);
if (color !== undefined) {
var imageData = hidden_context.getImageData(0, 0, imageObj.width, imageObj.height);
var data = imageData.data;
for (var i = 0; i < data.length; i += 4) {
var brightness = 0.34 * data[i] + 0.5 * data[i + 1] + 0.16 * data[i + 2];
//red
data[i] = brightness + color.R;
//green
data[i + 1] = brightness + color.G;
//blue
data[i + 2] = brightness + color.B;
}
//overwrite original image
hidden_context.putImageData(imageData, 0, 0);
}
var canvas = document.getElementById('card');
var context = canvas.getContext('2d');
context.drawImage(hidden_canvas, 0, 0);
};

This should do the job:
public static Bitmap MakeChromaChange(Bitmap bmp0, Color tCol, float gamma)
{
Bitmap bmp1 = new Bitmap(bmp0.Width, bmp0.Height);
using (Graphics g = Graphics.FromImage(bmp1))
{
float f = (tCol.R + tCol.G + tCol.B) / 765f;
float tr = tCol.R / 255f - f;
float tg = tCol.G / 255f - f;
float tb = tCol.B / 255f - f;
ColorMatrix colorMatrix = new ColorMatrix(new float[][]
{ new float[] {1f + tr, 0, 0, 0, 0},
new float[] {0, 1f + tg, 0, 0, 0},
new float[] {0, 0, 1f + tb, 0, 0},
new float[] {0, 0, 0, 1, 0},
new float[] {0, 0, 0, 0, 1} });
ImageAttributes attributes = new ImageAttributes();
attributes.SetGamma(gamma);
attributes.SetColorMatrix(colorMatrix);
g.DrawImage(bmp0, new Rectangle(0, 0, bmp0.Width, bmp0.Height),
0, 0, bmp0.Width, bmp0.Height, GraphicsUnit.Pixel, attributes);
}
return bmp1;
}
Note that I kept a gamma parameter; if you don't need it keep the value at 1f;
Here it is at work, adding first red then more red and some blue :
Transparent pixels are not affected.
For more on ColorMatrix here is a really nice intro!
As a fun project I applied the known colors to a known face:

SlimDX 11 Depth Buffer issues

I am getting an issue with SlimDX March SDK (For DXSDK11 June 2010 I believe). The problem is that whenever I turn the attach the depth view to the output merger state I don't get any output on the screen. I have compared my code with DX11 samples and it does seem to be correct. I have tried all sorts of flags and formats for the depth test (including always passing etc.) but nothing seems to work. I'd appreciate if anyone can spot a mistake. Here is the code. Here are the steps:
Initialize the back buffer:
D3DDevice device;
SwapChain swapChain;
/// Create the swap chain
SwapChainDescription desc = new SwapChainDescription()
{
BufferCount = 1,
ModeDescription = new ModeDescription
{
Width = ContextSettings.Width,
Height = ContextSettings.Height,
RefreshRate = new SlimDX.Rational(ContextSettings.RefreshRate, 1),
Format = ContextSettings.BufferFormat,
},
IsWindowed = !ContextSettings.FullScreen,
OutputHandle = WindowHandle,
SampleDescription = new SampleDescription(1, 0),
SwapEffect = SwapEffect.Discard,
Usage = Usage.RenderTargetOutput,
};
FeatureLevel[] featureLevels = new FeatureLevel[] { FeatureLevel.Level_11_0, FeatureLevel.Level_10_1 };
DriverType driverType = DriverType.Hardware;
D3DDevice.CreateWithSwapChain(driverType, DeviceCreationFlags.Debug, featureLevels, desc, out device, out swapChain);
Device = device;
SwapChain = swapChain;
/// Setup window association
Factory factory = swapChain.GetParent<Factory>();
factory.SetWindowAssociation(WindowHandle, WindowAssociationFlags.IgnoreAll);
/// Setup back buffers and render target views
RenderBuffer = DXTexture2D.FromSwapChain<DXTexture2D>(swapChain, 0);
RenderView = new RenderTargetView(Device, RenderBuffer);
Then initialize the depth buffer:
Format depthFormat = Format.D32_Float;
Texture2DDescription depthBufferDesc = new Texture2DDescription
{
ArraySize = 1,
BindFlags = BindFlags.DepthStencil,
CpuAccessFlags = CpuAccessFlags.None,
Format = depthFormat,
Height = width,
Width = height,
MipLevels = 1,
OptionFlags = ResourceOptionFlags.None,
SampleDescription = new SampleDescription( 1, 0 ),
Usage = ResourceUsage.Default
};
DepthBuffer = new DXTexture2D(Device, depthBufferDesc);
DepthStencilViewDescription dsViewDesc = new DepthStencilViewDescription
{
ArraySize = 0,
Format = depthFormat,
Dimension = DepthStencilViewDimension.Texture2D,
MipSlice = 0,
Flags = 0,
FirstArraySlice = 0
};
DepthView = new DepthStencilView(Device, DepthBuffer, dsViewDesc);
DepthStencilStateDescription dsStateDesc = new DepthStencilStateDescription()
{
IsDepthEnabled = true,
IsStencilEnabled = false,
DepthWriteMask = DepthWriteMask.All,
DepthComparison = Comparison.Less,
};
DepthState = DepthStencilState.FromDescription(Device, dsStateDesc);
Setup the render targets:
DeviceContext.OutputMerger.DepthStencilState = DepthState;
DeviceContext.OutputMerger.SetTargets(DepthView, RenderView);
DeviceContext.Rasterizer.SetViewports(new Viewport(0, 0, ContextSettings.Width, ContextSettings.Height, 0.0f, 1.0f));
Clear();
As soon as I remove DepthView from OutputMerger.SetTargets I start seeing images on the screen (without the depth test of course) and vice-versa otherwise.

It turned out that in the depthBufferDesc, I was passing width to the Height variable and height to the Width. This was creating the two render targets with different dimensions which was breaking it down.

How to do color balancing using a gray card in C#

I need to color balance an image that has an 18% gray card in it. The user loads this image into the application, then clicks on the gray card. From here is where I need help with an algorithm to color balance the image. I've found a few articles that mention doing a matrix transform, which I've tried, but without success (the image washes out or turns one color or another). The code I have now is:
int sampleSize = 20; // The square around the user's click on the gray card
int rVal = 0, gVal = 0, bVal = 0;
int count = 0;
for (int x = 0; x < sampleSize - 1; x++)
{
for (int y = 0; y < sampleSize - 1; y++)
{
System.Drawing.Color c = grayCardArea.GetPixel(x, y);
if (c.R > 0)
{
rVal += c.R;
gVal += c.G;
bVal += c.B;
rs.Add(c.R);
count++;
}
}
}
grayCardGraphics.Dispose();
int rAvg = 0, gAvg = 0, bAvg = 0;
rAvg = (int)Math.Round((decimal)rVal / (count));
gAvg = (int)Math.Round((decimal)gVal / (count));
bAvg = (int)Math.Round((decimal)bVal / (count));
// 117 is a value I found online for the neutral gray color of the gray card
float rDiff = (117 / (float)rAvg);
float gDiff = (117 / (float)gAvg);
float bDiff = (117 / (float)bAvg);
float[][] ptsArray =
{
new float[] {rDiff, 0, 0, 0, 0},
new float[] {0, gDiff, 0, 0, 0},
new float[] {0, 0, bDiff, 0, 0},
new float[] {0, 0, 0, 1, 0},
new float[] {0, 0, 0, .0f, 1}
};
// Create a ColorMatrix
ColorMatrix clrMatrix = new ColorMatrix(ptsArray);
// Create ImageAttributes
ImageAttributes imgAttribs = new ImageAttributes();
// Set color matrix
imgAttribs.SetColorMatrix(clrMatrix, ColorMatrixFlag.Default, ColorAdjustType.Default);
// Draw image with ImageAttributes
outputImageGraphics.DrawImage(srcImage, new System.Drawing.Rectangle(0, 0, srcImage.Width, srcImage.Height),
0, 0, srcImage.Width, srcImage.Height,
GraphicsUnit.Pixel, imgAttribs);
Viewing a saved copy of the outputImage shows an odd transformation of the image.
Any help is greatly appreciated!

My company, Atalasoft, has a free .NET Imaging SDK, with a class called LevelsCommand, that I think will do what you want.
http://atalasoft.com/photofree
Code is something like
AtalaImage img = new AtalaImage("filename");
LevelsCommand cmd = new LevelsCommand(/* ... */ ); // need to pass in leveling colors
img = cmd.Apply(img).Image;
img.Save("filename-new", new PngEncoder(), null); // or could be new JpegEncoder() or something else
You should use proper extensions on filenames to indicate the format.

Your first assumption appears to be that the image was properly exposed in the first place and that making the gray card read 117, 117, 117 will solve the problem. My advice is to leave the exposure alone and adjust just the color cast. You might find a different color model useful -- e.g., HSL. The saturation of a gray card should always be zero.
Alternatively, I have an example gray target reading 71, 72, 60. This is a bit warm. It would stand to reason that a more correct reading would be 67,67,67 or (R+G+B)/3. Because the image is a bit underexposed, I left it that way, but achieved a true neutral without altering the density of the image.
I hope this provides some help along your path toward getting the color right.