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POHow to crop or get a smaller size UIImage in iPhone without memory leaks?
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copied!<p>I am using a navigation controller in which I push a tableview Controller as follows:</p> <p>TableView *Controller = [[TableView alloc] initWithStyle:UITableViewStylePlain]; [self.navigationController pushViewController:Controller animated:NO]; [Controller release];</p> <p>In this table view I am using following two methods to display images:</p> <pre><code>- (UIImage*) getSmallImage:(UIImage*) img { CGSize size = img.size; CGFloat ratio = 0; if (size.width < size.height) { ratio = 36 / size.width; } else { ratio = 36 / size.height; } CGRect rect = CGRectMake(0.0, 0.0, ratio * size.width, ratio * size.height); UIGraphicsBeginImageContext(rect.size); [img drawInRect:rect]; return UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); } - (UIImage*)imageByCropping:(UIImage *)imageToCrop toRect:(CGRect)rect { //create a context to do our clipping in UIGraphicsBeginImageContext(rect.size); CGContextRef currentContext = UIGraphicsGetCurrentContext(); //create a rect with the size we want to crop the image to //the X and Y here are zero so we start at the beginning of our //newly created context CGFloat X = (imageToCrop.size.width - rect.size.width)/2; CGFloat Y = (imageToCrop.size.height - rect.size.height)/2; CGRect clippedRect = CGRectMake(X, Y, rect.size.width, rect.size.height); //CGContextClipToRect( currentContext, clippedRect); //create a rect equivalent to the full size of the image //offset the rect by the X and Y we want to start the crop //from in order to cut off anything before them CGRect drawRect = CGRectMake(0, 0, imageToCrop.size.width, imageToCrop.size.height); CGContextTranslateCTM(currentContext, 0.0, drawRect.size.height); CGContextScaleCTM(currentContext, 1.0, -1.0); //draw the image to our clipped context using our offset rect //CGContextDrawImage(currentContext, drawRect, imageToCrop.CGImage); CGImageRef tmp = CGImageCreateWithImageInRect(imageToCrop.CGImage, clippedRect); //pull the image from our cropped context UIImage *cropped = [UIImage imageWithCGImage:tmp];//UIGraphicsGetImageFromCurrentImageContext(); CGImageRelease(tmp); //pop the context to get back to the default UIGraphicsEndImageContext(); //Note: this is autoreleased*/ return cropped; } </code></pre> <p>But when I pop the Controller, the memory being used is not released. Is there any leaks in the above code used to create and crop images. </p> <p>Also are there any efficient method to deal with images in iPhone. I am having a lot of images and facing major challeges in resolving the memory issues.</p> <p>tnx in advance.</p>

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