UIImageView set image orienation after setting from camera roll - objective-c

Image Orientation changes after setting it from camera roll to UIImage.
UIImagePickerController *controller = [[UIImagePickerController alloc] init];
controller.sourceType = UIImagePickerControllerSourceTypeCamera;
controller.allowsEditing = NO;
controller.mediaTypes = [UIImagePickerController availableMediaTypesForSourceType: UIImagePickerControllerSourceTypeCamera];
controller.delegate = self;
[self.navigationController presentViewController: controller animated: YES completion: nil];
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{
[self.navigationController dismissViewControllerAnimated: YES completion: nil];
UIImage *image = [info valueForKey: UIImagePickerControllerOriginalImage];
NSData *imageData = UIImageJPEGRepresentation(image, 0.1);
headerCell.userProfileImageView.image = [UIImage imageWithData:imageData];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsPath = [paths objectAtIndex:0]; //Get the docs directory
NSString *filePath = [documentsPath stringByAppendingPathComponent:#"profileImage.png"]; //Add the file name
NSData *pngData = UIImagePNGRepresentation(image);
[pngData writeToFile:filePath atomically:YES];
}
From Camera Roll its set orientation wrong but from photo library its setting perfectly.
Any one had same issue like this please let us know your comments to fix this issue.

From thread here and below answer(by Dilip Rajkumar):
https://stackoverflow.com/a/10602363/5575752
You can use below method to manage image orientation after picking image:
(Modify method as per your requirement)
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{
[self.navigationController dismissViewControllerAnimated: YES completion: nil];
UIImage *image = [self scaleAndRotateImage: [info objectForKey:UIImagePickerControllerOriginalImage]];
NSData *imageData = UIImageJPEGRepresentation(image, 0.1);
headerCell.userProfileImageView.image = [UIImage imageWithData:imageData];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsPath = [paths objectAtIndex:0]; //Get the docs directory
NSString *filePath = [documentsPath stringByAppendingPathComponent:#"profileImage.png"]; //Add the file name
NSData *pngData = UIImagePNGRepresentation(image);
[pngData writeToFile:filePath atomically:YES];
}
- (UIImage *)scaleAndRotateImage:(UIImage *) image {
int kMaxResolution = 320;
CGImageRef imgRef = image.CGImage;
CGFloat width = CGImageGetWidth(imgRef);
CGFloat height = CGImageGetHeight(imgRef);
CGAffineTransform transform = CGAffineTransformIdentity;
CGRect bounds = CGRectMake(0, 0, width, height);
if (width > kMaxResolution || height > kMaxResolution) {
CGFloat ratio = width/height;
if (ratio > 1) {
bounds.size.width = kMaxResolution;
bounds.size.height = bounds.size.width / ratio;
}
else {
bounds.size.height = kMaxResolution;
bounds.size.width = bounds.size.height * ratio;
}
}
CGFloat scaleRatio = bounds.size.width / width;
CGSize imageSize = CGSizeMake(CGImageGetWidth(imgRef), CGImageGetHeight(imgRef));
CGFloat boundHeight;
UIImageOrientation orient = image.imageOrientation;
switch(orient) {
case UIImageOrientationUp: //EXIF = 1
transform = CGAffineTransformIdentity;
break;
case UIImageOrientationUpMirrored: //EXIF = 2
transform = CGAffineTransformMakeTranslation(imageSize.width, 0.0);
transform = CGAffineTransformScale(transform, -1.0, 1.0);
break;
case UIImageOrientationDown: //EXIF = 3
transform = CGAffineTransformMakeTranslation(imageSize.width, imageSize.height);
transform = CGAffineTransformRotate(transform, M_PI);
break;
case UIImageOrientationDownMirrored: //EXIF = 4
transform = CGAffineTransformMakeTranslation(0.0, imageSize.height);
transform = CGAffineTransformScale(transform, 1.0, -1.0);
break;
case UIImageOrientationLeftMirrored: //EXIF = 5
boundHeight = bounds.size.height;
bounds.size.height = bounds.size.width;
bounds.size.width = boundHeight;
transform = CGAffineTransformMakeTranslation(imageSize.height, imageSize.width);
transform = CGAffineTransformScale(transform, -1.0, 1.0);
transform = CGAffineTransformRotate(transform, 3.0 * M_PI / 2.0);
break;
case UIImageOrientationLeft: //EXIF = 6
boundHeight = bounds.size.height;
bounds.size.height = bounds.size.width;
bounds.size.width = boundHeight;
transform = CGAffineTransformMakeTranslation(0.0, imageSize.width);
transform = CGAffineTransformRotate(transform, 3.0 * M_PI / 2.0);
break;
case UIImageOrientationRightMirrored: //EXIF = 7
boundHeight = bounds.size.height;
bounds.size.height = bounds.size.width;
bounds.size.width = boundHeight;
transform = CGAffineTransformMakeScale(-1.0, 1.0);
transform = CGAffineTransformRotate(transform, M_PI / 2.0);
break;
case UIImageOrientationRight: //EXIF = 8
boundHeight = bounds.size.height;
bounds.size.height = bounds.size.width;
bounds.size.width = boundHeight;
transform = CGAffineTransformMakeTranslation(imageSize.height, 0.0);
transform = CGAffineTransformRotate(transform, M_PI / 2.0);
break;
default:
[NSException raise:NSInternalInconsistencyException format:#"Invalid image orientation"];
}
UIGraphicsBeginImageContext(bounds.size);
CGContextRef context = UIGraphicsGetCurrentContext();
if (orient == UIImageOrientationRight || orient == UIImageOrientationLeft) {
CGContextScaleCTM(context, -scaleRatio, scaleRatio);
CGContextTranslateCTM(context, -height, 0);
}
else {
CGContextScaleCTM(context, scaleRatio, -scaleRatio);
CGContextTranslateCTM(context, 0, -height);
}
CGContextConcatCTM(context, transform);
CGContextDrawImage(UIGraphicsGetCurrentContext(), CGRectMake(0, 0, width, height), imgRef);
UIImage *imageCopy = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return imageCopy;
}

Related

effective way to generate thumbnail from uiimage

I have an UICollectionView and each item shows a square image.
Each image is big file (> 3MB) and every time app try to jump into this view. It will delay 2-3 seconds.
I try to create a thumbnail from big file then apply to each collection item. But it seems not saving time.
Is there any effective way ?
Follow is the method I use to create thumbnail
-(UIImage*)resizedImageToSize:(CGSize)dstSize{
CGImageRef imgRef = self.CGImage;
// the below values are regardless of orientation : for UIImages from Camera, width>height (landscape)
CGSize srcSize = CGSizeMake(CGImageGetWidth(imgRef), CGImageGetHeight(imgRef)); // not equivalent to self.size (which is dependant on the imageOrientation)!
/* Don't resize if we already meet the required destination size. */
if (CGSizeEqualToSize(srcSize, dstSize)) {
return self;
}
CGFloat scaleRatio = dstSize.width / srcSize.width;
UIImageOrientation orient = self.imageOrientation;
CGAffineTransform transform = CGAffineTransformIdentity;
switch(orient) {
case UIImageOrientationUp: //EXIF = 1
transform = CGAffineTransformIdentity;
break;
case UIImageOrientationUpMirrored: //EXIF = 2
transform = CGAffineTransformMakeTranslation(srcSize.width, 0.0);
transform = CGAffineTransformScale(transform, -1.0, 1.0);
break;
case UIImageOrientationDown: //EXIF = 3
transform = CGAffineTransformMakeTranslation(srcSize.width, srcSize.height);
transform = CGAffineTransformRotate(transform, M_PI);
break;
case UIImageOrientationDownMirrored: //EXIF = 4
transform = CGAffineTransformMakeTranslation(0.0, srcSize.height);
transform = CGAffineTransformScale(transform, 1.0, -1.0);
break;
case UIImageOrientationLeftMirrored: //EXIF = 5
dstSize = CGSizeMake(dstSize.height, dstSize.width);
transform = CGAffineTransformMakeTranslation(srcSize.height, srcSize.width);
transform = CGAffineTransformScale(transform, -1.0, 1.0);
transform = CGAffineTransformRotate(transform, 3.0 * M_PI_2);
break;
case UIImageOrientationLeft: //EXIF = 6
dstSize = CGSizeMake(dstSize.height, dstSize.width);
transform = CGAffineTransformMakeTranslation(0.0, srcSize.width);
transform = CGAffineTransformRotate(transform, 3.0 * M_PI_2);
break;
case UIImageOrientationRightMirrored: //EXIF = 7
dstSize = CGSizeMake(dstSize.height, dstSize.width);
transform = CGAffineTransformMakeScale(-1.0, 1.0);
transform = CGAffineTransformRotate(transform, M_PI_2);
break;
case UIImageOrientationRight: //EXIF = 8
dstSize = CGSizeMake(dstSize.height, dstSize.width);
transform = CGAffineTransformMakeTranslation(srcSize.height, 0.0);
transform = CGAffineTransformRotate(transform, M_PI_2);
break;
default:
[NSException raise:NSInternalInconsistencyException format:#"Invalid image orientation"];
}
/////////////////////////////////////////////////////////////////////////////
// The actual resize: draw the image on a new context, applying a transform matrix
UIGraphicsBeginImageContextWithOptions(dstSize, NO, self.scale);
CGContextRef context = UIGraphicsGetCurrentContext();
if (!context) {
return nil;
}
if (orient == UIImageOrientationRight || orient == UIImageOrientationLeft) {
CGContextScaleCTM(context, -scaleRatio, scaleRatio);
CGContextTranslateCTM(context, -srcSize.height, 0);
} else {
CGContextScaleCTM(context, scaleRatio, -scaleRatio);
CGContextTranslateCTM(context, 0, -srcSize.height);
}
CGContextConcatCTM(context, transform);
// we use srcSize (and not dstSize) as the size to specify is in user space (and we use the CTM to apply a scaleRatio)
CGContextDrawImage(UIGraphicsGetCurrentContext(), CGRectMake(0, 0, srcSize.width, srcSize.height), imgRef);
UIImage* resizedImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return resizedImage;
}
There's a built in way to create thumbnails from compressed image files: directly using ImageIO. It is lightning fast compared to rendering the image into a smaller bitmap context.
Here's a method that does the job:
+ (UIImage *)thumbnailWithContentsOfURL:(NSURL *)URL maxPixelSize:(CGFloat)maxPixelSize
{
CGImageSourceRef imageSource = CGImageSourceCreateWithURL((__bridge CFURLRef)URL, NULL);
NSAssert(imageSource != NULL, #"cannot create image source");
NSDictionary *imageOptions = #{
(NSString const *)kCGImageSourceCreateThumbnailFromImageIfAbsent : (NSNumber const *)kCFBooleanTrue,
(NSString const *)kCGImageSourceThumbnailMaxPixelSize : #(maxPixelSize),
(NSString const *)kCGImageSourceCreateThumbnailWithTransform : (NSNumber const *)kCFBooleanTrue
};
CGImageRef thumbnail = CGImageSourceCreateThumbnailAtIndex(imageSource, 0, (__bridge CFDictionaryRef)imageOptions);
CFRelease(imageSource);
UIImage *result = [[UIImage alloc] initWithCGImage:thumbnail];
CGImageRelease(thumbnail);
return result;
}

In cocoa: why changing image size it also change image resolution?

I am using this code to change size to an image and then create a new file with new dimensions. All is working fine but it changes the image dpi resolution and I don't want that... the initial image dpi res is 328 and after the resizing it becomes 72... how to keep the original dpi resolution?
Here is my code:
- (void)scaleIcons:(NSString *)outputPath :(NSURL *)nomeImmagine
{
NSImage *image = [[NSImage alloc] initWithContentsOfFile:[nomeImmagine path]];
if (!image)
image = [[NSWorkspace sharedWorkspace] iconForFile:[nomeImmagine path]];
NSSize outputSize = NSMakeSize(512.0f,512.0f);
NSImage *anImage = [self scaleImage:image toSize:outputSize];
NSString *finalPath = [outputPath stringByAppendingString:#"/icon_512x512.png"];
NSData *imageData = [anImage TIFFRepresentation];
NSBitmapImageRep *rep = [NSBitmapImageRep imageRepWithData:imageData];
NSData *dataToWrite = [rep representationUsingType:NSPNGFileType properties:nil];
[dataToWrite writeToFile:finalPath atomically:NO];
}
- (NSImage *)scaleImage:(NSImage *)image toSize:(NSSize)targetSize
{
if ([image isValid])
{
NSSize imageSize = [image size];
float width = imageSize.width;
float height = imageSize.height;
float targetWidth = targetSize.width;
float targetHeight = targetSize.height;
float scaleFactor = 0.0;
float scaledWidth = targetWidth;
float scaledHeight = targetHeight;
NSPoint thumbnailPoint = NSZeroPoint;
if (!NSEqualSizes(imageSize, targetSize))
{
float widthFactor = targetWidth / width;
float heightFactor = targetHeight / height;
if (widthFactor < heightFactor)
{
scaleFactor = widthFactor;
}
else
{
scaleFactor = heightFactor;
}
scaledWidth = width * scaleFactor;
scaledHeight = height * scaleFactor;
if (widthFactor < heightFactor)
{
thumbnailPoint.y = (targetHeight - scaledHeight) * 0.5;
}
else if (widthFactor > heightFactor)
{
thumbnailPoint.x = (targetWidth - scaledWidth) * 0.5;
}
newImage = [[NSImage alloc] initWithSize:targetSize];
[newImage lockFocus];
NSRect thumbnailRect;
thumbnailRect.origin = thumbnailPoint;
thumbnailRect.size.width = scaledWidth;
thumbnailRect.size.height = scaledHeight;
[image drawInRect:thumbnailRect
fromRect:NSZeroRect
operation:NSCompositeSourceOver
fraction:1.0];
[newImage unlockFocus];
}
}
return newImage;
}
Any help will be very much appreciated! Thanks... Massy
Finally I've been able to change the res... using the code taken by the post pointed by trojanfoe... I added this to my code before to write the file:
NSSize pointsSize = rep.size;
NSSize pixelSize = NSMakeSize(rep.pixelsWide, rep.pixelsHigh);
CGFloat currentDPI = ceilf((72.0f * pixelSize.width)/pointsSize.width);
NSLog(#"current DPI %f", currentDPI);
NSSize updatedPointsSize = pointsSize;
updatedPointsSize.width = ceilf((72.0f * pixelSize.width)/328);
updatedPointsSize.height = ceilf((72.0f * pixelSize.height)/328);
[rep setSize:updatedPointsSize];
only problem now is that the final resolution is 321,894 and not 328... but it's already something!

How do I capture a zoomed UIImageView inside of a Scrollview to crop?

Problem:
Cropping with the image zoomed out is fine.
Cropping with the image zoomed in is showing the image above what is should be.
The yOffset I have in there is because the crop square I want starts below where the scrollview does.
Code:
CGRect rect;
float yOffset = 84;
rect.origin.x = floorf([scrollView contentOffset].x * zoomScale);
rect.origin.y = floorf(([scrollView contentOffset].y + yOffset) * zoomScale);
rect.size.width = floorf([scrollView bounds].size.width * zoomScale);
rect.size.height = floorf((320 * zoomScale));
if (rect.size.width > 320) {
rect.size.width = 320;
}
if (rect.size.height > 320) {
rect.size.height = 320;
}
CGImageRef cr = CGImageCreateWithImageInRect([[imageView image] CGImage], rect);
UIImage *img = imageView.image; //[UIImage imageWithCGImage:cr];
UIGraphicsBeginImageContext(rect.size);
// translated rectangle for drawing sub image
CGRect drawRect = CGRectMake(-rect.origin.x, -rect.origin.y, 320.0f, 320.0f);
NSLog(#"drawRect: %#", NSStringFromCGRect(drawRect));
NSLog(#"rect: %#", NSStringFromCGRect(rect));
// draw image
[img drawInRect:drawRect];
// grab image
UIImage *cropped = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
CGImageRelease(cr);
[self.delegate imageCropper:self didFinishCroppingWithImage:cropped];
What am I doing that is causing the image to get the wrong height when zooming?
UIImage* imageFromView(UIImage* srcImage, CGRect* rect)
{
CGImageRef cr = CGImageCreateWithImageInRect(srcImage.CGImage, *rect);
UIImage* cropped = [UIImage imageWithCGImage:cr];
CGImageRelease(cr);
return cropped;
}
-(void) doneEditing
{
//Calculate the required area from the scrollview
CGRect visibleRect;
float scale = 1.0f/scrollView.zoomScale;
visibleRect.origin.x = scrollView.contentOffset.x * scale;
visibleRect.origin.y = scrollView.contentOffset.y * scale;
visibleRect.size.width = scrollView.bounds.size.width * scale;
visibleRect.size.height = scrollView.bounds.size.height * scale;
FinalOutputView* outputView = [[FinalOutputView alloc] initWithNibName:#"FinalOutputView" bundle:[NSBundle mainBundle]];
outputView.image = imageFromView(imageView.image, &visibleRect);
[self.navigationController pushViewController:outputView animated:YES];
[outputView release];
}
Loading Orginal Image:
Zooming Image:
Finally Capturing the Image
If you want to take screenshot from the whole view of scrollView (after zooming) you can do this:
UIImage* image = nil;
UIGraphicsBeginImageContext(self.scrollView.contentSize);
{
//save previous frames
CGPoint savedContentOffset = self.scrollView.contentOffset;
CGRect savedFrame = self.scrollView.frame;
CGRect imgFrame = self.imageView.frame;
//set the frames with current content size
self.scrollView.contentOffset = CGPointZero;
self.scrollView.frame = CGRectMake(0, 0, self.scrollView.contentSize.width, self.scrollView.contentSize.height);
self.imageView.frame = self.scrollView.frame;
//render image now :)
[self.scrollView.layer renderInContext: UIGraphicsGetCurrentContext()];
image = UIGraphicsGetImageFromCurrentImageContext();
//now set the frames again with old ones :)
self.scrollView.contentOffset = savedContentOffset;
self.scrollView.frame = savedFrame;
self.imageView.frame = imgFrame;
[self viewForZoomingInScrollView:self.scrollView];
}
UIGraphicsEndImageContext();
//get the documents path
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
//save file as savedImage.png
NSString *savedImagePath = [documentsDirectory stringByAppendingPathComponent:#"savedImage.png"];
//get the png data from image
NSData *imageData = UIImagePNGRepresentation(image);
//write it now
[imageData writeToFile:savedImagePath atomically:NO];

How to compress and scale down an NSImage?

This is my compress code
NSBitmapImageRep* tmpRep = [[_image representations] objectAtIndex:0];
[tmpRep setPixelsWide:512];
[tmpRep setPixelsHigh:512];
[tmpRep setSize:NSMakeSize(SmallThumbnailWidth, SmallThumbnailHeight)];
NSDictionary* imageProps = [NSDictionary dictionaryWithObject:[NSNumber numberWithFloat:0.3] forKey:NSImageCompressionFactor];
NSData* outputImageData = [tmpRep
representationUsingType:NSJPEGFileType properties:imageProps];
NSString* imageFilePath = [NSString stringWithFormat:#"%#/thumbnail.jpg",imagePath];
[outputImageData writeToFile:imageFilePath atomically:YES];
The original image size is 960*960.I want to compress the original image into 512*512.But the output Image's size is 960*960 when I check it in finder and the location size which compares with the original has really been compressed.Any one could tell me why ? thank you
Try this one:
This will reduce the saving size in kbs:
-(NSImage *)imageCompressedByFactor:(float)factor{
NSBitmapImageRep *imageRep = [[NSBitmapImageRep alloc] initWithData:[self TIFFRepresentation]];
NSDictionary *options = [NSDictionary dictionaryWithObject:[NSNumber numberWithFloat:factor] forKey:NSImageCompressionFactor];
NSData *compressedData = [imageRep representationUsingType:NSJPEGFileType properties:options];
return [[NSImage alloc] initWithData:compressedData];
}
This will reduce the file size in pixels :
Copied from here
#implementation NSImage (ProportionalScaling)
- (NSImage*)imageByScalingProportionallyToSize:(NSSize)targetSize{
NSImage* sourceImage = self;
NSImage* newImage = nil;
if ([sourceImage isValid]){
NSSize imageSize = [sourceImage size];
float width = imageSize.width;
float height = imageSize.height;
float targetWidth = targetSize.width;
float targetHeight = targetSize.height;
float scaleFactor = 0.0;
float scaledWidth = targetWidth;
float scaledHeight = targetHeight;
NSPoint thumbnailPoint = NSZeroPoint;
if ( NSEqualSizes( imageSize, targetSize ) == NO )
{
float widthFactor = targetWidth / width;
float heightFactor = targetHeight / height;
if ( widthFactor < heightFactor )
scaleFactor = widthFactor;
else
scaleFactor = heightFactor;
scaledWidth = width * scaleFactor;
scaledHeight = height * scaleFactor;
if ( widthFactor < heightFactor )
thumbnailPoint.y = (targetHeight - scaledHeight) * 0.5;
else if ( widthFactor > heightFactor )
thumbnailPoint.x = (targetWidth - scaledWidth) * 0.5;
}
newImage = [[NSImage alloc] initWithSize:targetSize];
[newImage lockFocus];
NSRect thumbnailRect;
thumbnailRect.origin = thumbnailPoint;
thumbnailRect.size.width = scaledWidth;
thumbnailRect.size.height = scaledHeight;
[sourceImage drawInRect: thumbnailRect
fromRect: NSZeroRect
operation: NSCompositeSourceOver
fraction: 1.0];
[newImage unlockFocus];
}
return [newImage autorelease];
}
#end
Create a category method like so, in order to incrementally compress the image till you meet the desired file size:
- (NSImage*) compressUnderMegaBytes:(CGFloat)megabytes {
CGFloat compressionRatio = 1.0;
NSBitmapImageRep *imageRep = [[NSBitmapImageRep alloc] initWithData:[self TIFFRepresentation]];
NSDictionary *options = [NSDictionary dictionaryWithObject:[NSNumber numberWithFloat:compressionRatio] forKey:NSImageCompressionFactor];
NSData *compressedData = [imageRep representationUsingType:NSJPEGFileType properties:options];
while ([compressedData length]>(megabytes*1024*1024)) {
#autoreleasepool {
compressionRatio = compressionRatio * 0.9;
options = [NSDictionary dictionaryWithObject:[NSNumber numberWithFloat:compressionRatio] forKey:NSImageCompressionFactor];
compressedData = [imageRep representationUsingType:NSJPEGFileType properties:options];
// Safety check, 0.4 is a reasonable compression size, anything below will become blurry
if (compressionRatio <= 0.4) {
break;
}
}
}
return [[NSImage alloc] initWithData: compressedData];
}
You can then use it like this:
NSImage *compressedImage = [myImage compressUnderMegaBytes: 0.5];
level from 0.0 to 1.0
func getImageQualityWithLevel(image: NSImage, level: CGFloat) -> NSImage {
let _image = image
var newRect: NSRect = NSMakeRect(0, 0, _image.size.width, _image.size.height)
let imageSizeH: CGFloat = _image.size.height * level
let imageSizeW: CGFloat = _image.size.width * level
var newImage = NSImage(size: NSMakeSize(imageSizeW, imageSizeH))
newImage.lockFocus()
NSGraphicsContext.currentContext()?.imageInterpolation = NSImageInterpolation.Low
_image.drawInRect(NSMakeRect(0, 0, imageSizeW, imageSizeH), fromRect: newRect, operation: NSCompositingOperation.CompositeSourceOver, fraction: 1)
newImage.unlockFocus()
return newImage
}

Render a single UIImage and rotation has to be applied

I have rendered few UIImage objects using CGContextDrawImage. But when i apply rotation to the image, it is not applied and the view disappears.
code here
-(void )renderImage: (ItemView *)array
{
NSArray *selectedImages = self.slideView.selectedView.subviews;
CGSize combinedSize = CGSizeMake(0, 0);
for (int i = 0; i < [selectedImages count]; ++i) {
CGSize sourceSize = [selectedImages[i] size];
NSLog(#"sdfsd %f %f ", sourceSize.width, sourceSize.height);
combinedSize.width = MAX(combinedSize.width, sourceSize.width);
combinedSize.height += sourceSize.height;
}
UIGraphicsBeginImageContextWithOptions(self.view.frame.size, NO, 0);
CGContextRef context = UIGraphicsGetCurrentContext();
{
CGContextTranslateCTM(context, 0, 768);
CGContextScaleCTM(context, 1,-1);
for (int i = 0; i < [selectedImages count]; ++i) {
UIImageView *imageview = selectedImages[i];
UIImage *sourceImage = imageview.image;
CGContextSaveGState(context);
float radians1 = atan2(imageview.transform.a, imageview.transform.b);
CGFloat angle = [(NSNumber *)[imageview valueForKeyPath:#"layer.transform.rotation.z"] floatValue];
printf("\n radians %f",radians1);
printf("\n angle %f",angle);
CGContextRotateCTM(context, radians(angle));
CGContextDrawImage(context, imageview.frame, imageview.image.CGImage);
CGContextRestoreGState(context);
//CGContextDrawImage(context, imageview.frame, imageview.image);
}
}
UIImage *combinedImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageWriteToSavedPhotosAlbum(combinedImage, nil, nil, nil);
}
Thanks,
Any help would be appreciated
Let's say you have an array of source images:
NSArray *sourceImages = ...;
// each element of sourceImages is a UIImage
Now you want to take the first count images from the array and concatenate them vertically into a new image. Start by figuring out the size of the combined image:
CGSize combinedSize = CGSizeMake(0, 0);
for (int i = 0; i < count; ++i) {
CGSize sourceSize = [sourceImages[i] size];
combinedSize.width = MAX(combinedSize.width, sourceSize.width);
combinedSize.height += sourceSize.height;
}
Next, create a graphics context of that size:
UIGraphicsBeginImageContextWithOptions(combinedSize, NO, 0); {
Now draw each component image into the graphics context at the appropriate position:
CGFloat y = 0;
for (int i = 0; i < count; ++i) {
UIImage *sourceImage = sourceImages[i];
[sourceImage drawAtPoint:CGPointMake(0, y)];
y += sourceImage.size.height;
}
Finally, create the combined image from the context and dispose of the context:
}
UIImage *combinedImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
Read Drawing and Printing Guide for iOS - Drawing and Creating Images for more information.
I cracked the answer . # rob mayoff : Thanks much who helped me out.
code here
//code to render group of images excluding the image which has been selected in a particular view
-(void )renderImage: (ItemView *)selectedItem
{
NSArray *selectedImages = self.slideView.selectedView.subviews;
int selectedItemIndex = [selectedImages indexOfObject:selectedItem];
if(selectedItem.image==nil){
[selectedItem loadImageFromFile];
}
// first set
UIGraphicsBeginImageContextWithOptions(self.slideView.selectedView.frame.size, NO, 0);
for (int i = 0; i < selectedItemIndex; ++i) {
if([selectedImages[i] isKindOfClass:[ItemView class]]){
ItemView *imageview = (ItemView *)selectedImages[i];
CGAffineTransform transform = imageview.transform;
imageview.transform = CGAffineTransformIdentity;
UIImage *image = [[UIImage alloc] initWithContentsOfFile:imageview.filename];
UIImageView *renderImageView = [[UIImageView alloc] initWithImage:image]; //[imageview copy];
renderImageView.frame = imageview.frame;
renderImageView.bounds = imageview.bounds;
imageview.transform = transform;
renderImageView.transform = transform;
renderImageView.center = CGPointMake(imageview.frame.size.width/2,imageview.frame.size.height/2);
UIView *view = [[UIView alloc] initWithFrame:renderImageView.frame];
view.backgroundColor = [UIColor clearColor];
[view addSubview:renderImageView];
[renderImageView release];
[image release];
imageview.image = nil;
UIGraphicsBeginImageContext(imageview.frame.size);
CGContextRef context1 = UIGraphicsGetCurrentContext();
[view.layer renderInContext:context1];
UIImage *result = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
[view release];
[result drawAtPoint:imageview.frame.origin];
}
}
UIImage *combinedImage1 = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
//UIImageWriteToSavedPhotosAlbum(combinedImage1, nil, nil, nil);
if (groupBgImage1) {
[groupBgImage1 removeFromSuperview];
[groupBgImage1 release];
groupBgImage1 = nil;
}
groupBgImage1 = [[UIImageView alloc] initWithImage:combinedImage1];
[self.slideView.selectedView insertSubview:groupBgImage1 belowSubview:selectedItem ];
// second set
UIGraphicsBeginImageContextWithOptions(self.slideView.selectedView.frame.size, NO, 0);
for (int i = selectedItemIndex+1; i < [selectedImages count]; ++i) {
if([selectedImages[i] isKindOfClass:[ItemView class]]){
ItemView *imageview = (ItemView *)selectedImages[i];
CGAffineTransform transform = imageview.transform;
imageview.transform = CGAffineTransformIdentity;
UIImage *image = [[UIImage alloc] initWithContentsOfFile:imageview.filename];
UIImageView *renderImageView = [[UIImageView alloc] initWithImage:image]; //[imageview copy];
renderImageView.frame = imageview.frame;
renderImageView.bounds = imageview.bounds;
imageview.transform = transform;
renderImageView.transform = transform;
renderImageView.center = CGPointMake(imageview.frame.size.width/2,imageview.frame.size.height/2);
UIView *view = [[UIView alloc] initWithFrame:renderImageView.frame];
view.backgroundColor = [UIColor clearColor];
[view addSubview:renderImageView];
[renderImageView release];
[image release];
imageview.image = nil;
UIGraphicsBeginImageContext(imageview.frame.size);
CGContextRef context1 = UIGraphicsGetCurrentContext();
[view.layer renderInContext:context1];
UIImage *result = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
[view release];
[result drawAtPoint:imageview.frame.origin];
}
}
UIImage *combinedImage2 = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageWriteToSavedPhotosAlbum(combinedImage2, nil, nil, nil);
if (groupBgImage2) {
[groupBgImage2 removeFromSuperview];
[groupBgImage2 release];
groupBgImage2 = nil;
}
groupBgImage2 = [[UIImageView alloc] initWithImage:combinedImage2];
[self.slideView.selectedView insertSubview:groupBgImage2 aboveSubview:selectedItem ];
}