I have two for loops and I wanna save that data in one array. The first for loop will create 5 rectangles in the array. After that, the second for loop will create 5 rectangles and add them to the array. But something doesn't work. I get that "Index was outside the bounds of the array" error message in the last line of the code and I don't know what to change.
int framewidth = texture.Width / sourceRects.Length;
int frameheight = texture.Height;
private void vorrück(Rectangle[] sourceRects, int framewidth, int frameheight)
{
int doublelenght = sourceRects.Length * 2;
for (int i = 0; i < sourceRects.Length; i++)
sourceRects[i] = new Rectangle(i * framewidth, 0, framewidth, frameheight);
for (int normallenght = sourceRects.Length; normallenght < doublelenght; normallenght++)
sourceRects[normallenght] = new Rectangle((sourceRects.Length - 1 - normallenght) * framewidth, 0, framewidth, frameheight);
}
You get this error because the size of your Rectangle[] array is smaller than 10. Keep in mind that when you declare your Rectangle[] array, you should at least declare it with a size of 10.
Rectangle[] sourceRects = new Rectangle[10]; //(it will be from 0 to 9)
You will then be able to add 10 rectangles to it.
You need a bigger array.
The second loop very clearly writes outside the bounds, the relevant details are:
for (int normallenght = sourceRects.Length; ...; ...)
sourceRects[normallenght] = ...; // normallenght >= sourceRects.Length
As a general solution, do not use arrays so much. In this case a List<Rectangle> is probably the preferred datastructure.
You have made 2 mistakes (missing resize and second for never works).
Look at my modified code:
private void vorrück(ref Rectangle[] sourceRects, int framewidth, int frameheight)
{
int doublelenght = sourceRects.Length * 2;
for (int i = 0; i < sourceRects.Length; i++)
{
sourceRects[i] = new Rectangle(i * framewidth, 0, framewidth, frameheight);
}
Array.Resize(ref sourceRects, doublelenght);
for (int normallenght = sourceRects.Length /2; normallenght < doublelenght; normallenght++)
{
sourceRects[normallenght] = new Rectangle((sourceRects.Length - 1 - normallenght) * framewidth, 0, framewidth, frameheight);
}
}
This code will resize and fill your sourceRects array.
You can use this code like this:
Rectangle[] sourceRects = new Rectangle[2];
vorrück(ref sourceRects,5,4);
Related
I am trying to perform a basic number-only OCR on an image by comparing it to bitmaps of the numbers 0 - 9, using the code below. I have tried to follow the code in the answer to this question, but it is not returning the correct results. There are 2 main issues that I am facing:
1: If the program determines that the number 0 is present at any given point, then it also determines that 1, 2, 3, ... , and 9 are present at that location, which is obviously not true.
2: The locations that it finds numbers in ... most of the locations are blank (white) spaces.
I'll be the first to admit that using the lockbits method is new to me, as I usually use the getPixel() method of comparing, but it was far too slow for this project, so I may be making a rookie mistake or 2.
Thanks for the help!!!
P.S. The image to OCR is RTA, and I believe everything else is self-explanatory.
void newOCR()
{
Rectangle rect = new Rectangle(0, 0, 8, 9);
Rectangle numRect = new Rectangle(0, 0, 8, 9);
for (int i = 0; i < RTA.Width - 8; i++)
{
for (int j = 0; j < RTA.Height - 9; j++)
{
rect.Location = new Point(i, j);
for (int n = 0; n < numbers.Length; n++)
{
System.Drawing.Imaging.BitmapData data = RTA.LockBits(rect, System.Drawing.Imaging.ImageLockMode.ReadOnly, RTA.PixelFormat);
System.Drawing.Imaging.BitmapData numData = numbers[n].LockBits(numRect, System.Drawing.Imaging.ImageLockMode.ReadOnly, numbers[n].PixelFormat);
unsafe
{
byte* ptr = (byte*)data.Scan0.ToPointer();
byte* numPtr = (byte*)data.Scan0.ToPointer();
int width = rect.Width * Image.GetPixelFormatSize(data.PixelFormat) / 8;
for(int y = 0; y < rect.Height; y++)
{
bool outBreak = false;
for(int x = 0; x < width; x++)
{
if(*ptr != *numPtr)
{
outBreak = true;
break;
}
else if(y == rect.Height - 1 && x == width - 1)
{
timeDict.Add(new Point(i, j), n);
}
ptr++;
numPtr++;
}
if(outBreak)
{
break;
}
ptr += data.Stride - width;
numPtr += numData.Stride - width;
}
RTA.UnlockBits(data);
numbers[n].UnlockBits(numData);
}
}
}
}
}
There is a (probably copy/paste) mistake in the following line
byte* numPtr = (byte*)data.Scan0.ToPointer();
which is causing comparing the bitmap to itself. It should be
byte* numPtr = (byte*)numData.Scan0.ToPointer();
I have two images(original and noisy). I'm calculating PSNR. I kinda did it for color RGB images, but i don't know how to do it with grayscale. As i read, MSE calculation is different. For RGB i'm doing it like you can see in following code (I'm using Visual C#):
for (int i = 0; i < bmp1.Width; i++)
{
for (int j = 0; j < bmp1.Height; j++)
{
mseR += Math.Pow(bmp1.GetPixel(i, j).R - bmp2.GetPixel(i, j).R, 2);
mseG += Math.Pow(bmp1.GetPixel(i, j).G - bmp2.GetPixel(i, j).G, 2);
mseB += Math.Pow(bmp1.GetPixel(i, j).B - bmp2.GetPixel(i, j).B, 2);
}
}
mse = (mseR + mseG + mseB) / ((bmp1.Width * bmp1.Height) * 3);
Here I am manipulating with R,G,B of pixels.But i don't know what should i take in case of grayscale images. Can I use RGB aswell, because it actually gives some results, or i should take something else?
To make grayscale you can make the picture out of averages (no need to vary your implementation). I'm assuming your images are bmp1 = grayImage and bmp2 = noisy image.
for (int i = 0; i < bmp1.Width; i++)
{
for (int j = 0; j < bmp1.Height; j++)
{
// As a grayscale image has rthe same color on all RGB just pick one
int gray1 = bmp1.GetPixel(i, j).R;
int gray2 = bmp2.GetPixel(i, j).R;
double sum = Math.Pow(gray1 - gray2, 2)
mseGray += sum;
}
}
mse = (mseGray) / ((bmp1.Width * bmp1.Height) * 3);
Also getting pixels one at a time is a slow process look into using the indexes, and a optimization in the loop. It should give about a tenfold in performance.
You need to make the bitmap into an indexable img, I'm assuming its BitmapSource for this example. the interesting part is the loop and the index building and not the precode, the precode is just to make the image indexable.
var height = bmp1.Height;
var width = bmp1.Width;
var pixelBytes1 = new byte[height * width * 4];
var pixelBytes2 = new byte[height * width * 4];
bmp1.CopyPixels(pixelBytes1, stride, 0);
bmp2.CopyPixels(pixelBytes2, stride, 0);
for (int x = 0; x < width; x++)
{
int woff = x * height;
for (int y = 0; y < height; y++)
{(R*0.3 + G*0.59+ B*0.11)
int index = woff + y;
int gray1 = bmp1[index];
int gray2 = bmp2[index];
double sum = Math.Pow(gray1 - gray2, 2)
mseGray += sum;
}
}
mse = (mseGray) / ((bmp1.Width * bmp1.Height) * 3);
EDIT:
http://www.mathworks.com/matlabcentral/answers/49906-how-to-calculate-psnr-of-compressed-images-and-how-to-compare-psnr-of-images-compressed-by-two-diff
I'm having an issue with your implementation of PSNR though im thinking its not per definition
here is an example from java (very similar to C#)
http://www.cyut.edu.tw/~yltang/program/Psnr.java
I'm doing some image processing and ran in to an exception.
Let me explain the logic process;
Resize the image to to a smaller size
Turn it grayscale
Threshold the image
Save it for use later on.
When you threshold the image, the constructor can take an int that sets the intensity of the filter. The best way I've found to get this "magic number" is to use a method called GetOtsuThreshold. It uses unsafe code but works well. However, something strange happens when you call that method. After you call the otsu method, it causes the Aforge...Threshold.ApplyInPlace() method to throw a Parameter is not valid exception. If you don't call it (When the code is commented out) the whole thing runs just fine though.
Wot's the deal?
EDIT: Found the problem; You must put a new a new image into the otsu method because it disposes of the image!!
using System;
using System.Drawing;
using System.Drawing.Imaging;
using AForge.Imaging.Filters;
namespace Puma.Ocr.Tests
{
class FormatImage
{
public static Bitmap _FullImageOfCoin;
public FormatImage(string path)
{
_FullImageOfCoin = ScaleImage(new Bitmap(path), 2000, 2000);
GrayscaleImage();
ThresholdImage();
}
private void GrayscaleImage()
{
Grayscale filter = new Grayscale(0.2125, 0.7154, 0.0721);
// apply the filter
_FullImageOfCoin = filter.Apply(_FullImageOfCoin);
}
private void ThresholdImage()
{
//Causes the exception
Threshold threshold = new Threshold(getOtsuThreshold(_FullImageOfCoin));
//Runs fine
//Threshold threshold = new Threshold();
threshold.ApplyInPlace(_FullImageOfCoin);
_FullImageOfCoin.Save(#"C:\users\school\desktop\thresholded.bmp");
}
public static Bitmap ScaleImage(Bitmap image, int maxWidth, int maxHeight)
{
var ratioX = (double)maxWidth / image.Width;
var ratioY = (double)maxHeight / image.Height;
var ratio = Math.Min(ratioX, ratioY);
var newWidth = (int)(image.Width * ratio);
var newHeight = (int)(image.Height * ratio);
var newImage = new Bitmap(newWidth, newHeight);
Graphics.FromImage(newImage).DrawImage(image, 0, 0, newWidth, newHeight);
return newImage;
}
public int getOtsuThreshold(Bitmap bmp)
{
byte t = 0;
float[] vet = new float[256];
int[] hist = new int[256];
vet.Initialize();
float p1, p2, p12;
int k;
BitmapData bmData = bmp.LockBits(new Rectangle(0, 0, bmp.Width, bmp.Height),
ImageLockMode.ReadOnly, PixelFormat.Format24bppRgb);
unsafe
{
byte* p = (byte*)(void*)bmData.Scan0.ToPointer();
getHistogram(p, bmp.Width, bmp.Height, bmData.Stride, hist);
for (k = 1; k != 255; k++)
{
p1 = Px(0, k, hist);
p2 = Px(k + 1, 255, hist);
p12 = p1 * p2;
if (p12 == 0)
p12 = 1;
float diff = (Mx(0, k, hist) * p2) - (Mx(k + 1, 255, hist) * p1);
vet[k] = (float)diff * diff / p12;
}
}
bmp.UnlockBits(bmData);
t = (byte)findMax(vet, 256);
bmp.Dispose();
return t;
}
private unsafe void getHistogram(byte* p, int w, int h, int ws, int[] hist)
{
hist.Initialize();
for (int i = 0; i < h; i++)
{
for (int j = 0; j < w * 3; j += 3)
{
int index = i * ws + j;
hist[p[index]]++;
}
}
}
private int findMax(float[] vec, int n)
{
float maxVec = 0;
int idx = 0;
int i;
for (i = 1; i <= n - 1; i++)
{
if (vec[i] > maxVec)
{
maxVec = vec[i];
idx = i;
}
}
return idx;
}
private float Px(int init, int end, int[] hist)
{
int sum = 0;
int i;
for (i = init; i <= end; i++)
sum += hist[i];
return (float)sum;
}
// function is used to compute the mean values in the equation (mu)
private float Mx(int init, int end, int[] hist)
{
int sum = 0;
int i;
for (i = init; i <= end; i++)
sum += i * hist[i];
return (float)sum;
}
}
}
A few ideas:
Use debugging and follow this method step by step to see if it is well working
Your getOtsuThreshold(Bitmap bmp) is returning an int, but the variable t returned is a byte: try to cast the value?
If the int returned by getOtsuThreshold is okay, check that the value is in the good range provided the API info (http://www.aforgenet.com/framework/docs/html/503a43b9-d98b-a19f-b74e-44767916ad65.htm):
Since the filter can be applied as to 8 bpp and to 16 bpp images, the
ThresholdValue value should be set appropriately to the pixel format.
In the case of 8 bpp images the threshold value is in the [0, 255]
range, but in the case of 16 bpp images the threshold value is in the
[0, 65535] range.
Alright, found the answer. By putting the _Fullimage of coin into the otsu method it stripped the variable of all it properties. I don't know how, but by putting a new Bitmap into the otsu method it fixed the problem.
Similar to many programs that take a tiled map, like that in the game Terraria, and turn the map into a single picture of the entire map, I am trying to do something similar. The problem is, my block textures are in a single large texture atlas and are referenced by index, and I am having trouble taking the color data from a single block and placing it into the correct place in the larger texture.
This is my code so far.
Getting the source from the index (this code works):
public static Rectangle GetSourceForIndex(int index, Texture2D tex)
{
int dim = tex.Width / TEXTURE_MAP_DIM;
int startx = index % TEXTURE_MAP_DIM;
int starty = index / TEXTURE_MAP_DIM;
return new Rectangle(startx * dim, starty * dim, dim, dim);
}
Getting the texture at the index (Where the problems start):
public static Texture2D GetTextureAtIndex(int index, Texture2D tex)
{
Rectangle source = GetSourceForIndex(index, tex);
Texture2D texture = new Texture2D(_device, source.Width, source.Height);
Color[] colors = new Color[tex.Width * tex.Height];
tex.GetData<Color>(colors);
Color[] colorData = new Color[source.Width * source.Height];
for (int x = 0; x < source.Width; x++)
{
for (int y = 0; y < source.Height; y++)
{
colorData[x + y * source.Width] = colors[x + source.X + (y + source.Y) * tex.Width];
}
}
texture.SetData<Color>(colorData);
return texture;
}
Putting the texture into the larger picture (this is completely wrong I'm sure):
private void doSave()
{
int texWidth = this._rWidth * Region.REGION_DIM * 16;
int texHeight = this._rHeight * Region.REGION_DIM * 16;
Texture2D picture = new Texture2D(Game.GraphicsDevice, texWidth, texHeight);
Color[] pictureData = new Color[picture.Width * picture.Height];
for (int blockX = 0; blockX < texWidth / 16; blockX++)
{
for (int blockY = 0; blockY < texHeight / 16; blockY++)
{
Block b = this.GetBlockAt(blockX, blockY);
Texture2D toCopy = TextureManager.GetTextureAtIndex(b.GetIndexBasedOnMetadata(b.GetMetadataForSurroundings(this, blockX, blockY)), b.GetTextureFile());
Color[] copyData = new Color[toCopy.Width * toCopy.Height];
Rectangle source = new Rectangle(blockX * 16, blockY * 16, 16, 16);
toCopy.GetData<Color>(copyData);
for (int x = 0; x < source.Width; x++)
{
for (int y = 0; y < source.Height; y++)
{
pictureData[x + source.X + (y + source.Y) * picture.Width] = copyData[x + y * source.Width];
}
}
}
}
picture.SetData<Color>(pictureData);
string fileName = "picture" + DateTime.Now.ToString(#"MM\-dd\-yyyy-h\-mm-tt");
FileStream stream = File.Open(this.GetSavePath() + #"Pictures\" + fileName, FileMode.OpenOrCreate);
picture.SaveAsPng(stream, picture.Width, picture.Height);
I can't find any good descriptions on how to properly convert between the texture and a one dimensional color array. It would be much easier if I knew how to easily and properly place a square of colors into a larger two dimensional texture.
TL;DR: How do you put a smaller Texture into a larger texture?
Create a RenderTarget2D the size of you largest texture and set it to active. Draw the large texture then draw the smaller one. Set the reference to the original texture to the RenderTarget2D you just drew to.
int texWidth = this._rWidth * Region.REGION_DIM * 16;
int texHeight = this._rHeight * Region.REGION_DIM * 16;
_renderTarget = new RenderTarget2D(GraphicsDevice, texWidth, texHeight);
GraphicsDevice.SetRenderTarget(_renderTarget);
GraphicsDevice.Clear(Color.Transparent);
_spriteBatch.Begin(SpriteSortMode.Immediate, BlendState.Opaque);
for (int blockX = 0; blockX < texWidth / 16; blockX++)
{
for (int blockY = 0; blockY < texHeight / 16; blockY++)
{
_spriteBatch.Draw(
TextureManager.GetTextureAtIndex(b.GetIndexBasedOnMetadata(b.GetMetadataForSurroundings(this, blockX, blockY)), b.GetTextureFile()),
new Rectangle(blockX * 16, blockY * 16, 16, 16),
Color.White);
}
}
_spriteBatch.End()
GraphicsDevice.SetRenderTarget(null);
var picture = _renderTarget;
At last I have something displayed. Switched to using graphics.GraphicsDevice.DrawIndexedPrimitives ... Next problem... Only one triangle is displayed. The data set is about 200 triangles. I formatted the data coming in to make sure every three consecutive vectors form a triangle face. These are irregular triangles forming an irregular shape. I don't fully understand the indexing of the vertices. Looks like each 3 indices form a triangle. If that is so then the indices match the data coming in. I did this:
int i4 = -1;
indices = new int[xData1.Count];
for (int i2 = 0; i2 < xData1.Count; i2++)
{
i4++;
cubeVertices[i4].Position = new Vector3((float)xData1[i2][0], (float)xData1[i2][1], (float)xData1[i2][2]);
cubeVertices[i4].Color = Color.LawnGreen;
indices[i4] = i4;
}
making the indices match the vertices coming in.. then I used Reimers normal calc to provide normals.. this is probably wrong as his example was using 6 vertices per index (I think!), like this:
for (int i = 0; i < cubeVertices.Length; i++)
cubeVertices[i].Normal = new Vector3(0, 0, 0);
for (int i = 0; i < indices.Length / 3; i++)
{
int index1 = indices[i * 3];
int index2 = indices[i * 3 + 1];
int index3 = indices[i * 3 + 2];
Vector3 side1 = cubeVertices[index1].Position - cubeVertices[index3].Position;
Vector3 side2 = cubeVertices[index1].Position - cubeVertices[index2].Position;
Vector3 normal = Vector3.Cross(side1, side2);
cubeVertices[index1].Normal += normal;
cubeVertices[index2].Normal += normal;
cubeVertices[index3].Normal += normal;
}
for (int i = 0; i < cubeVertices.Length; i++)
cubeVertices[i].Normal.Normalize();
how many things do I need to fix here? I am only seeing 1 out of a couple of hundred triangles
:(
thx for your patience
public struct VertexPositionColorNormal
{
public Vector3 Position;
public Color Color;
public Vector3 Normal;
public readonly static VertexDeclaration VertexDeclaration = new VertexDeclaration
(
new VertexElement(0, VertexElementFormat.Vector3, VertexElementUsage.Position, 0),
new VertexElement(sizeof(float) * 3, VertexElementFormat.Color, VertexElementUsage.Color, 0),
new VertexElement(sizeof(float) * 3 + 4, VertexElementFormat.Vector3, VertexElementUsage.Normal, 0)
);
}
...
private void CopyToBuffers()
{
vertexBuffer = new VertexBuffer(graphics.GraphicsDevice, VertexPositionColorNormal.VertexDeclaration,
cubeVertices.Length, BufferUsage.WriteOnly);
vertexBuffer.SetData(cubeVertices);
myIndexBuffer = new IndexBuffer(graphics.GraphicsDevice, typeof(int), indices.Length, BufferUsage.WriteOnly);
myIndexBuffer.SetData(indices);
}
....
foreach (EffectPass pass in basicEffect.CurrentTechnique.Passes)
{
basicEffect.World = world;
basicEffect.View = view;
basicEffect.Projection = proj;
pass.Apply();
graphics.GraphicsDevice.Indices = myIndexBuffer;
graphics.GraphicsDevice.SetVertexBuffer(vertexBuffer);
graphics.GraphicsDevice.DrawIndexedPrimitives(PrimitiveType.TriangleList, 0, 0,
cubeVertices.Length, 0, indices.Length / 3);
Your normal calculation is correct, and even if it was wrong the only thing that would happen is that your triangles would receive the wrong lightning.
You're using indices which exactly match the order of the vertices coming in, which is in itself redundant. If you switch to not setting the indices at all and use DrawPrimitives instead with the primitive count the same does that make a difference?
Other than that, are you sure that the data you're giving it is valid? Are the vertex positions correctly set?