![]() ![]() First, it extends the ImageV example by adding a menu item you can use to display the color depth of the current bitmap, by using the corresponding PixelFormat property: The BmpDraw example uses this information about the internal structure of a bitmap and some other technical features to take direct handling of bitmaps to a new level. ![]() Actually, all TPicture does is to manage a registered list of graphic classes. For compressed images in Delphi, you can use the TJpegImage class and the support for the JPEG format offered by the TPicture class. This can reduce the size of the image, but in some cases it will make it grow. The BMP format actually has a very limited form of compression, known as Run-Length Encoding (RLE), in which subsequent pixels with the same color are replaced by the number of such pixels followed by the color. This is efficient for moving the data from memory to the screen, but it is not an effective way to store information BMP files are generally very large, and they perform no compression. All the values that make up a line are stored sequentially in a memory block. Internally the bitmap format is very simple, whatever the color depth. ![]() To make things more complex, when the system draws a bitmap on a computer with a different color capability, it has to perform some conversion. An 8-bit bitmap usually has a companion palette to indicate how the 256 different colors map to the actual system colors, a 24-bit bitmap indicates the system color directly. In a 1-bit bitmap, each point can be either black or white (to be more precise, 1-bit bitmaps can have a color palette, allowing the bitmap to represent any two colors and not just black and white). BMP files are usually device-independent bitmaps.Īnother difference relates to the color depth-that is, the number of different colors the bitmap can use or, in other words, the number of bits required for storing each pixel. Bitmaps can be device-independent or not, a term used to indicate whether the bitmap has extra palette management information. There are different types of bitmaps in Windows. When the Image control is connected to a bitmap, there are some additional operations you can do, but before we examine them, I have to introduce bitmap formats. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. Archives
December 2022
Categories |