image-manipulation

问题 Objective: take a UIImage, crop out a square in the middle, change size of square to 320x320 pixels, slice up the image into 16 80x80 images, save the 16 images in an array. Here's my code: CGImageRef originalImage, resizedImage, finalImage, tmp; float imgWidth, imgHeight, diff; UIImage *squareImage, *playImage; NSMutableArray *tileImgArray; int r, c; originalImage = [image CGImage]; imgWidth = image.size.width; imgHeight = image.size.height; diff = fabs(imgWidth - imgHeight); if(imgWidth >

问题 I'm trying to create an image mask that from a composite of two existing images. First I start with creating the composite which consists of a small image that is the masking image, and a larger image which is the same size as the background: UIImage * BaseTextureImage = [UIImage imageNamed:@"background.png"]; UIImage * MaskImage = [UIImage imageNamed:@"my_mask.jpg"]; UIImage * ShapesBase = [UIImage imageNamed:@"largerimage.jpg"]; UIImage * MaskImageFull; CGSize finalSize = CGSizeMake(480.0,

问题 OK i thought i understood this function but i have a complete mental block on this one. I wanted to create cropped thumbnails of size 75x75 from photos that are 800x536. the imagecopyresampled function has 10 possible parameters. i first tried this: // Starting point of crop $tlx = floor(($width / 2) - ($new_width / 2)); //finds halfway point of big image and subtracts half of thumb. $tly = floor(($height / 2) - ($new_height / 2)); //gets centre of image to be cropped. imagecopyresampled($tmp

问题 OK i thought i understood this function but i have a complete mental block on this one. I wanted to create cropped thumbnails of size 75x75 from photos that are 800x536. the imagecopyresampled function has 10 possible parameters. i first tried this: // Starting point of crop $tlx = floor(($width / 2) - ($new_width / 2)); //finds halfway point of big image and subtracts half of thumb. $tly = floor(($height / 2) - ($new_height / 2)); //gets centre of image to be cropped. imagecopyresampled($tmp

问题 i'm using codeigniter to build a project and right now i need to create a thumb depending on user choice. like he will give me X1,Y1,X2,Y2,X3,Y3,X4,Y4 i want to crop the image depending on that 4 points. i checked the image manipulation class. the crop function seems to be very strange. any help please ? 回答1: I know that the documentation is sparse on this particular function in the image library. The crop function asks you only to supply to axises. It will then cut along these axes and

问题 I'd like to make a simple VB utility to resize images using vb.net. I am having trouble figuring out what vb class to use to actually manipulate the images. The Image class and the Bitmap class don't work. Any ideas, hints, tips, tutorial links are greatly appreciated. Thanks. 回答1: Here is an article with full details on how to do this. Private Sub btnScale_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles btnScale.Click ' Get the scale factor. Dim scale_factor As

问题 I have this code to mask an image. Basically, I only work with PNG images. So I have a 300x400 PNG image with 24bits of color (PNG-24). I am not sure if it also has an alpha channel. But there's no transparency in it. Then, there is the image mask which is PNG-8bit without alpha channel. It is just black, grayscale and white. I create both images as UIImage. Both display correctly when putting them into an UIImageView. Then I create an UIImage out of them which contains the results of the

问题 I need to cut this image into three parts using PIL and pick the middle part. How do I do it? http://thedilbertstore.com/images/periodic_content/dilbert/dt110507dhct.jpg 回答1: If the boxes are not known on before hand I would run a simple edge finding filter over the image (both x and y directions) to find the boundaries of the box. A simple approach would be: Run horizontal edge filter over image. You now have an image where each pixel describes the changes in intensity left and right of that

问题 I've got an image that I've scanned, but the white paper is not white on the screen. Is there a way to equalize the contract/brightness to make the background whiter? Update I've tried the suggested Image._EqualizeHist function from EmguCv: string file = @"IMG_20120512_055533.jpg"; Image<Bgr, byte> originalColour = new Image<Bgr, byte>(file); Image<Bgr, byte> improved = originalColour.Clone(); improved._EqualizeHist(); But get an even worse result (also when first gray scaled): Am I missing

问题 Closed. This question is off-topic. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 4 years ago . I want to develop an application which shows photos like digital picture frame (One by one photo slides automatically and shows animation). How to do it ? Is there any sdk available or I have to do it by my own logic ? Please help me if anyone can suggest any reference link. 回答1: This is not exactly an answer