Exposure values from camera can be acquired when you take picture (without saving it to SavedPhotos). A light meter application on iPhone does this. What is the appropriate way to get these values? The aforementioned application does this on iPhone 3GS only, so I guess it may be somehow related to EXIF data which is populated with this...
My application lets the user save/load images with alpha values to the camera roll on the device. I can see in the Photos application that these images are appropriately alpha'd, as alpha'd areas just appear black. However, when I load these images back into the application using the valueForKey:UIImagePickerControllerOriginalImage messa...
I use CGContexts to allow the user to draw in my application, here's an example: CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound); CGContextSetLineWidth(UIGraphicsGetCurrentContext(), size); CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(),r,g,b,a); I want the user to have an "eraser" tool that a...
I would like to handle out of memory errors in iPhone to execute logic with lesser memory requirements in case I run of of memory. In particular, I would like to do something very similar to the following pseudo-code: UIImage* image; try { image = [UIImage imageNamed:@"high_quality_image.png"]; } catch (OutOfMemoryException e) { ...
I am designing an application where a user places multiple UIImageViews one over another. When the user decides to save this to photo album, I have to combine all these UIImageViews and save it to Photo Library. While combining them I need to preserve their positions, resolutions, zorder. The approach I tried I was to have a parent UIVie...
I have two image views, one on top of the another, with two different images. As the user touches the image and moves his/her finger, the top image should become transparent along the touch points with a fixed radius. (Like the PhotoChop app). Currently I am doing it this way... For each touch. Get a copy of the image buffer from CGIm...
Hello all I was wondering how it's possible to find out if an image in the iPhone photo library is isotropic or anisotropic. Basically how many millimeters each pixel measures in height and in width. In JPG images the information is hardcoded into the data stream so it's possible to do by simply pointing a const char* to the image fil...
Hi, I'm creating an image from a view whith the folowing code : UIGraphicsBeginImageContext(myView.bounds.size); [myView.layer renderInContext:UIGraphicsGetCurrentContext()]; UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); UIImageWriteToSavedPhotosAlbum(viewImage, nil, nil, nil); The...
Hey all! I'm using ASyncSocket to move some UIImages from one device over to another. Essentially, on one device I have: NSMutableData *data = UIImageJPEGRepresentation(image, 0.1); if(isRunning){ [sock writeData:data withTimeout:-1 tag:0]; } So a new image will be added to the socket every so often (like a webcam). Then, on ...
Hi there, I have a UIImage with white background. I would like replace the white background/pixels with alpha-transparent pixels. I've looked at other questions on StackOverflow, along with Quartz documentation, but have yet to find a coherent "start-to-end" for this problem. How is this done? ...
Hello, I have requirement of selecting a portion of UIImage displayed on iPhone screen (for e.g. selecting the face from the image of some human being) using some rectangular type of frame. It means a rectangular type of frame can be moved across the image to place it at portion that we want. After placing it, I need to resize the fra...
Hello, I am saving image in the camera roll using UIImageWriteToSavedPhotosAlbum but always get an black thumbnail even if the picture is correct. Do you have pointers to address this? Thanks in advance for your help. Regards, ...
I'm using UIImageView to run a flipbook anim like this: mIntroAnimFrame = [[UIImageView alloc] initWithFrame:CGRectMake( 0, 0, 480, 320); mIntroAnimFrame.image = [UIImage imageNamed:@"frame0000.tif"]; Basically, when determine it is time, I flip the image by just calling: mIntroAnimFrame.image = [UIImage imageNamed:@"frame0000.tif"];...
I display an image in a UIImageView (within a UIScrollView) which is also stored in CoreData. In the interface, I want the user to be able to rotate the picture by 90 degrees. I also want it to be saved in CoreData. What should I rotate in the display? the scrollview, the uiimageview or the image itself? (If possible I would like the r...
I have a UIImageView with an image in it. I have rotated the image prior to display by setting the transform property of the UIImageView to CGAffineTransformMakeRotation(angle) where angle is the angle in radians. I want to be able to create another UIImage that corresponds to the rotated version that I can see in my view. I am almost...
I am using following code to resize the image. Resize a UIImage Right Way And I use interpolation quality as kCGInterpolationLow. And then I use UIImageJPEGRepresentation(image,0.0) to get the NSData of that image. Still its a little bit high in size around 100kb. when I send it over the network. Can I reduce it further. If I am to r...
Hi everyone, I just wanted to confirm, is it possible that we add layers of images using UImageView, one as background and other on top of it. I mean i want to use 2 images one has to be in the background and the other on top of it. ( the size of both these images is 320 x 480 ). Through the attributes inspector we cant do it. Is the...
Hi all, I'm replacing an uiimage of uiimageview before calling NSURLConnection sendSynchronousRequest, an as a result i don't see the new uiimage. How i can resolve this? tnx ...
Hi, I am working on an iPhone project, and have two themes defined under different directories, with most files share the same names (like background.png, image1.png, image2.png, etc). I have had them imported into xcode under different group names (group1, group2). How do I tell UIImage to load an image from a given group, say, I want...
I am able to load over 200 UIImage objects into a NSMutableDictionary without any memorry warning issues. When I start displaying them on the screen (after about showing 10-20 images) I get low memory warnings and an eventual crash. Only about 8 images are displayed at anyone time. Does it take additional memory to actually draw a UII...