pixels

问题 I'm currently following a series on Java game development from scratch. I understand most java and oop concepts but have very little experience when dealing with graphics and hardware acceleration. The lines of code that I am questioning are: private BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB); private int[] pixels = ((DataBufferInt) image.getRaster().getDataBuffer()).getData(); The BufferedImage "image" variable is always the variable being drawn to the

问题 I am desperately trying to create an Image from a pixel-array with integer values. Regardless of using the WritableImage or the Canvas, it is always said that the PixelFormat is BYTE_RGB or BYTE_BGRA_PRE, so that I am forced to use a byte-array. Is there any way to change the PixelFormat to <IntBuffer> or did I overlook another component that is capable of having a PixelFormat<IntBuffer> ? 回答1: You haven't described the structure of the pixel data in your int[] , but you can do something

问题 I have looked at many articles and answers to questions on how the Viola-Jones algorithm really works. I keep finding the answers saying the "sum of pixels" in a certain region subtracted by the "sum of pixels" in the adjacent region. I'm confused on what "sum of pixels" means. What is the value based on? Is it the number of pixels in the area? The intensity of the color? Thanks in advance. 回答1: These are the definitions based on Viola-Jones paper on 'Robust Real-time Object Detection'

问题 Im doing some image processing and I have the coordinates of the 4 points of a quadrilateral. (something like a trapezium) How can i get the coordinates of all the pixels inside it? I'm using Java by the way. Thanks! 回答1: You need scanline polygon filling. Here's a quick PDF lecture on the subject: http://www.cs.binghamton.edu/~reckert/460/lect11_2009-areafill-transformations.pdf Here's a web page example with some sample C code and a good illustration of the basic idea: http://alienryderflex

问题 I want to write pixels directly to to screen (not using vertices and polygons). I have investigated a variety of answers to similar questions, the most notable ones here and here. I see a couple ways drawing pixels to the screen might be possible, but they both seem to be indirect and use unnecessary floating point operations: Draw a GL_POINT for each pixel on the screen. I've tried this and it works, but this seems like an inefficient way to draw pixels onto the screen. Why write my data in

问题 I have an integer array of RGB pixels that looks something like: pixels[0] = <rgb-value of pixel(0,0)> pixels[1] = <rgb-value of pixel(1,0)> pixels[2] = <rgb-value of pixel(2,0)> pixels[3] = <rgb-value of pixel(0,1)> ...etc... And I'm trying to create a BufferedImage from it. I tried the following: BufferedImage img = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); img.getRaster().setPixels(0, 0, width, height, pixels); But the resulting image has problems with the color bands.

问题 I want to change pixel in a grayscale pgm image. When I compile the following code it shows image is read-only. I can not change the pixel of the image. How can I fix this error? Here are my codes: from PIL import Image img = Image.open('Image.pgm') pixval= img.load() columnsize, rowsize = img.size img1 = Image.open('Image.pgm') pix1 = img1.load() for i in range(rowsize): for j in range(columnsize): pix1[j,i]=250 img1.save("share1.pgm") 回答1: In order to change a pixel, use the following API

问题 I have a byte array containing pixel values from a .bmp file. It was generated by doing this: BufferedImage readImage = ImageIO.read(new File(fileName)); byte imageData[] = ((DataBufferByte)readImage.getData().getDataBuffer()).getData(); Now I need to recreate the .bmp image. I tried to make a BufferedImage and set the pixels of the WritableRaster by calling the setPixels method. But there I have to provide an int[], float[] or double[] array. Maybe I need to convert the byte array into one

问题 I have a byte array containing pixel values from a .bmp file. It was generated by doing this: BufferedImage readImage = ImageIO.read(new File(fileName)); byte imageData[] = ((DataBufferByte)readImage.getData().getDataBuffer()).getData(); Now I need to recreate the .bmp image. I tried to make a BufferedImage and set the pixels of the WritableRaster by calling the setPixels method. But there I have to provide an int[], float[] or double[] array. Maybe I need to convert the byte array into one

问题 Is it possible to read pixels of an image in canvas A and create pixels on canvas B? And I want to create the new pixels on Canvas B only where the image's pixels are green. eg. If images' pixel (120,45) is green I need to create a green colored pixel in Canvas B at (120,45) 回答1: You can use canvas ImageData to get color values for each pixels. The function: context.getImageData(left, top, width, height); returns an ImageData object, which consists of the following properties: width height