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8 bpp raw file


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I am trying to work with some heightmaps in Paint.net, and am looking to write a plugin that will do the following:

Load and save an 8bpp greyscale image. No header information, just the pixel data in a RGB format. I tried using the RawLoader plugin, and mucked around with its settings but no dice. I am currently using Gimp for this, but would like to be able to use PDN for it all. I am new to C# as well, but here was my first stab at doing this:

int width = 257;
               int height = 257;

               byte[] data = new byte[width * height];

               for (int index = 0; index < width * height; index++)
                   data [index] = (byte)input.ReadByte ();

               Bitmap bmp = new Bitmap(width, height, PixelFormat.Format8bppIndexed);

               //Create a BitmapData and Lock all pixels to be written
               BitmapData bmpData = bmp.LockBits(
                                    new Rectangle(0, 0, bmp.Width, bmp.Height),
                                    ImageLockMode.WriteOnly, bmp.PixelFormat);

               //Copy the data from the byte array into BitmapData.Scan0
               System.Runtime.InteropServices.Marshal.Copy(data, 0, bmpData.Scan0, data.Length);

               //Unlock the pixels

               return Document.FromImage(bmp);

It loads the image, but it is all messed up. I am pretty sure it has to do with the PixelFormat. Is there an easier way to do this?



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protected unsafe override Document OnLoad(Stream input)
//create our surface
           Surface surface = new Surface(width, height);
//grab a pointer to the image's memory
           ColorBgra* ptr = surface.GetRowAddress(0);

           int b;
//loop through the stream. (+perf by making a buffer and reading a few bytes at a time?)
           for (int i = 0; i             {
               b = input.ReadByte();
//set the pixel's a to opaque, and r,g,and b to the read value
               ptr->Bgra = (uint)((255 ;
//move to the next pixel in memory.

           return Document.FromImage(surface.CreateAliasedBitmap());

A lot of room for improvement, performance-wise, but it does the trick. I think. Worked with the images I tested, anyway.


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[i write plugins and stuff]

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