Generating bitmap image

Question

Hi I'm having trouble generating an image from data that I simulate using one of my own programs written in C. Could anyone give me a hand and point me in the right direction please? I can generate the 'raw data' in any convenient format. The trouble is that I'm yet to crack the image 'encoding' that will then allow me to display it on the screen. I'm new to GDI+ (and .NET and C# for that matter) and I have been reading 'Graphics Programming with GDI+' by M. Chand. Even though the book is makes for easy reading with an awful lot of examples it mostly focus on manipulating images. I have followed one of its many tutorials and I now have a little application written in C# that opens & displays different image formats and that can convert & save the image to a different format. I only require a single colour - usually grey for this type of application - with associated intensity gradient. I was told that 'BMP' was an appropriate bitmap format for my needs. Could anyone tell me how I should write the simulated data to file so that I can then open it as a bitmap image please? Many thanks TM

shas_ip · Answer

Can you explain your problem more clearly. but try to read about LockBits property of Bitmap class

ahuttere · Answer

I have a same problem. We can't : -copy each pixel. -Save to file. Must be a matrix at memory . Because if you want to do samething like animations you need at least 30 images per second.... So we need some instruction like memcpy(..) in C that can do at once. Ariel

shas_ip · Answer

Hi You can also display the raw data in a file or in an array with out saving it as a bmp file. As follows: First create a Bitmap object as shown Assume your data is in ImageData[][]; Bitmap bmp=new Bitmap(this.pictureBox4.Widththis.pictureBox4.HeightPixelFormat.Format24bppRgb); Then assign this bmp to the picturebox as this.pictureBox4.Image=(Image)bmp; Then using SetPixel property of Bitmap object change the color of each pixel with your raw(simulated) data as shown for(int i=0;i<bmp.width;i++) { for(int j=0;i<bmp.length;j++) bmp.SetPixel(ij)=ImageData[i][j]; } You also can use LockBits method of Bitmap object which is more useful for faster applications. Feel free to ask doubts if any

spgilmore · Answer

Could anyone tell me how I should write the simulated data to file so that I can then open it as a bitmap image please?  If you want to use a BMP image in your C# program then you should probably write a BMP image to disk. If you need to know the format of a raw BMP file see www.wotsit.org (or STW on google). It's all over the web. If you want to write it there using C# this is easily done. If you're not concerned with preserving details you may store it in a compressed format such as PNG or JPG then convert to BMP when you load it it makes no difference. Any image that is loaded is treated as a generic image after that anyway. Hence it doesn't matter which format you use on disk except that some are lossy and some aren't.