Tutorial by Examples

An image represents a rectangular grid of picture elements (pixel). In the image package, the pixel is represented as one of the color defined in image/color package. The 2-D geometry of the image is represented as image.Rectangle, while image.Point denotes a position on the grid. The above figur...

In memory, an image can be seen as a matrix of pixel (color). However, when an image being stored in a permanent storage, it may be stored as is (RAW format), Bitmap or other image formats with particular compression algorithm for saving storage space, e.g. PNG, JPEG, GIF, etc. When loading an image...

Most of image type in image package having SubImage(r Rectangle) Image method, except image.Uniform. Based on this fact, We can implement a function to crop an arbitrary image as follows func CropImage(img image.Image, cropRect image.Rectangle) (cropImg image.Image, newImg bool) { //Interface ...

Some digital image processing algorithm such as edge detection, information carried by the image intensity (i.e. grayscale value) is sufficient. Using color information (R, G, B channel) may provides slightly better result, but the algorithm complexity will be increased. Thus, in this case, we need ...