I am taking the screenshot of my last viewed Screen, by the following code
//Image Code
UIImage *nextImage;
CGImageRef imgRef = CGBitmapContextCreateImage(UIGraphicsGetCurrentContext());
nextImage = [UIImage imageWithCGImage:imgRef];
CGImageRelease(imgRef);
CGContextRelease(UIGraphicsGetCurrentContext());
When i displayed the the image in the console i got the O/P like: UIImage: 0x929c760
The Problem lies here for me, When converting that UIImage to NSData i am getting null.
The things i have tried are
//tried
NSData *data = UIImagePNGRepresentation(nextImage);
NSData *data2 = UIImageJPEGRepresentation(nextImage, 1.0);
Hi everyone i have got the solution to my Question as given by the link by #NP Compete
//getting screenshot i haven't used any UIImageview so my code goes as following
-(UIImage*)doImageOperation
{
UIImage *image = [[UIImage alloc]init];
UIGraphicsBeginImageContext(self.bounds.size);
[self.layer renderInContext:UIGraphicsGetCurrentContext()];
image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSLog(#"image in cg %#",image);
[self saveImage:image];
return image;
}
// Saved into Documents Directory
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
path = [documentsDirectory stringByAppendingPathComponent:
[NSString stringWithString:#"test.png"]];
data = UIImagePNGRepresentation(image);
[data writeToFile:path atomically:YES];
NSData *data = UIImagePNGRepresentation(image1);
NSLog(#"data %#",data);
Related
So I have a function which gets an image from a URL which looks like this:
- (UIImage *) getImageFromURL:(NSString *)fileURL {
UIImage * result;
NSData * img_data = [NSData dataWithContentsOfURL:[NSURL URLWithString:fileURL]];
result = [UIImage imageWithData:img_data];
return result;
}
and then a function which saves the image from a UIImage Which looks like this:
-(void) saveImage:(UIImage *)image withFileName:(NSString *)imageName ofType:(NSString *)extension inDirectory:(NSString *)directoryPath {
if ([[extension lowercaseString] isEqualToString:#"png"]) {
[UIImagePNGRepresentation(image) writeToFile:[directoryPath stringByAppendingPathComponent:[NSString stringWithFormat:#"%#.%#", imageName, #"png"]] options:NSAtomicWrite error:nil];
} else if ([[extension lowercaseString] isEqualToString:#"jpg"] || [[extension lowercaseString] isEqualToString:#"jpeg"]) {
[UIImageJPEGRepresentation(image, 1.0) writeToFile:[directoryPath stringByAppendingPathComponent:[NSString stringWithFormat:#"%#.%#", imageName, #"jpg"]] options:NSAtomicWrite error:nil];
NSLog(#"Image named %# wrote to %#", imageName, directoryPath);
} else {
NSLog(#"Image Save Failed\nExtension: (%#) is not recognized, use (PNG/JPG)", extension);
}
}
The issue I am facing is that when I run a UIImage through the saveImage function I dont think it is saving the image. This is because when I check for a UIImage imageNamed:#"Documents/filenamesavedas.jpeg" it returns (null). The image does however download correctly.
Here is my Documents Directory path function:
- (NSString *)getDocumentsDirectoryPath {
NSString * documentsDirectoryPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSLog(documentsDirectoryPath);
return documentsDirectoryPath;
}
Here is where I am downloading and trying to save the image:
dispatch_async(jsonQueue, ^{
// check to see if data authenticate runs successfully.
NSString *documentsDirectoryPath = [util getDocumentsDirectoryPath];
UIImage *imageToSave = [util getImageFromURL:[properties objectForKey:#"current_group_logoURL"]];
[util saveImage:imageToSave withFileName:[properties objectForKey:#"home_venue_logo"] ofType:#"jpeg" inDirectory:documentsDirectoryPath];
NSLog(#"Group Logo URL %#", [properties objectForKey:#"current_group_logoURL"]);
NSLog(#"Current Group Image %#", [properties objectForKey:#"home_venue_logo"]);
UIImage *testToSeeItHasDownloaded = imageToSave;
NSString *imageLocation = [documentsDirectoryPath stringByAppendingPathComponent:[properties objectForKey:#"home_venue_logo"]];
NSData *data = [NSData dataWithContentsOfFile:imageLocation];
UIImage *testToSeeImageHasSaved = [UIImage imageWithData:data];
NSLog(#"testToSeeImagehasDownloaded: %#", testToSeeItHasDownloaded);
NSLog(#"image location to save to: %#", imageLocation);
NSLog(#"testToSeeImagehasSaved: %#", testToSeeImageHasSaved );
});
The Console returns this:
2012-10-22 16:27:45.642 asdaf[46819:1d807] Group Logo URL http://somesite.com/50a0e42619424ba551a956511c098656.jpeg
2012-10-22 16:27:45.642 asdaf[46819:1d807] Current Group Image 50a0e42619424ba551a956511c098656.jpeg
2012-10-22 16:27:45.649 asdaf[46819:1d807] testToSeeImagehasDownloaded: <UIImage: 0xb09ed50>
2012-10-22 16:27:45.649 asdaf[46819:1d807] testToSeeImagehasSaved: (null)
testToSeeImagehasSaved should return null. But what am I doing wrong? Thanks.
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
//documentsDirectory is your documents directory path
//Now append your image name in this path
NSString *imagePath = [documentsDirectory stringByAppendingPathComponent:#"ImageName.jpeg"];
//convert your image in NSData
NSData *imageData = UIImagePNGRepresentation(image);
//Now write it at path
[imageData writeToFile:imagePath atomically:NO];
You can get this image in same way
NSData *data = [NSData dataWithContentsOfFile:imagePath];
UIImage *image = [UIImage imageWithData:data];
Edit:
-(void)saveImage:(UIImage *)image withFileName:(NSString *)imageName ofType:(NSString *)extension
{
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *imageName = [imageName stringByAppendingString:extension];
//Note extension should be like .png, .jpg, .jpeg dont forget dot (.).
NSString *imagePath = [documentsDirectory stringByAppendingPathComponent:imageName];
NSData *imageData = UIImagePNGRepresentation(image);
[imageData writeToFile:imagePath atomically:NO];
}
Well i dont now about your whole code but why you're passing an UIImage object when you have to save your image in documents directory. You can pass NSData as well in your method. You're doing more.
Your problem is you're saving .jpg image each time and at the time of retrieving you're trying to find .jpeg image on same path thats why you're getting null value. See this line in your saving method -
[UIImageJPEGRepresentation(image, 1.0) writeToFile:[directoryPath stringByAppendingPathComponent:[NSString stringWithFormat:#"%#.%#", imageName, #"jpg"]] options:NSAtomicWrite error:nil];
this line doesn't look right to me:
UIImage *testToSeeImageHasSaved = [UIImage imageNamed: [#"Documents/" stringByAppendingString: [properties objectForKey:#"home_venue_logo"]]];
I think you have to do:
UIImage* image = [UIImage imageWithContentsOfFile:"YOUR_FILE_PATH"];
[UIImage imageNamed:"image_name"] is good only for images attached to your project
When you save it in the document folder, it does not exacly saves it in the "Document" directory but rather something like
path=/var/mobile/Applications/144B3628-5258-4939-8B80-006EC5BE45B2/Library/Caches/6_1.png
So to retreive your image you should use
NSString *uniquePath = [directory stringByAppendingPathComponent: filename];
image = [UIImage imageWithContentsOfFile: uniquePath];
where directory is the path you used to save it and filename the name of your jpeg.
[UIImage imageNamed:#"Documents/filenamesavedas.jpeg"]
Doesnt take paths it searches your bundle for the file with a specific name.
Locate the file using calls to NSFileManager and use the expected path and file name.
in one of the example of GLImageProcessing i m just changing the way of getting image but app get crashed help me please i have change the way in such a manner
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *savedImagePath = [documentsDirectory stringByAppendingPathComponent:#"savedImage.png"];
// UIImage *image = image; // imageView is my image from camera
UIImage* img11 = [UIImage imageNamed:#"image1.jpg"];
NSData *imageData = UIImagePNGRepresentation(img11);
[imageData writeToFile:savedImagePath atomically:NO];
NSArray *paths1 = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory1 = [paths1 objectAtIndex:0];
NSString *getImagePath1 = [documentsDirectory1 stringByAppendingPathComponent:#"savedImage.png"];
UIImage *imgGet = [UIImage imageWithContentsOfFile:getImagePath1];
CGImageRef CGImage = imgGet.CGImage;
However earlier way was ....
CGImageRef CGImage = [UIImage imageNamed:[NSString stringWithUTF8String:name]].CGImage;
I am not much sure but UIImagePNGRepresentation gives internal data so read it back as data and then convert it into image using following lines.
NSData *data1 = [NSData dataWithContentsOfFile:#"filePath"];
UIImage *uiImage = [[UIImage alloc] initWithData:data1];"
Please consider following block also. Put check for nil to avoid unexpected execution.
Return Value
An autoreleased data object containing the PNG data, or nil if there was a problem generating the data. This function may return nil if the image has no data or if the underlying CGImageRef contains data in an unsupported bitmap format.
Check if above is helpful...
I have pulled an image out of the UIImagePicker thingy, and I would like to temporarily save it to the sandbox environment, in either the documents folder, or some other similar equivalent. However, I do not know how to do this, please could someone help me? Thanks
At the moment the image is a UIImage
Saving an image:
-(void)saveImage:(UIImage*)image{
NSString *imagePath = [NSHomeDirectory() stringByAppendingPathComponent:#"Documents/someImageName.png"];
[UIImagePNGRepresentation(image) writeToFile:imagePath atomically:YES];
}
Loading an image
-(UIImage)loadImage{
NSString *imagePath = [NSHomeDirectory() stringByAppendingPathComponent:#"Documents/someImageName.png"];
UIImage *image = [UIImage imageWithContentsOfFile:imagePath];
}
-(void)SaveImage
{
NSData *data;
NSArray *paths;
NSString *documentsDirectory,*imagePath ;
UIImage *image=[UIImage imageNamed:#"public.png"];
paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
documentsDirectory = [paths objectAtIndex:0];
imagePath = [documentsDirectory stringByAppendingPathComponent:[NSString stringWithFormat:#"public.png"]];
data = UIImagePNGRepresentation(image);
[data writeToFile:imagePath atomically:YES];
}
Hi i cant seem to get his code to work
//Save Image To Device
UIImage *image = [[UIImage alloc] initWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:[self.ImageURLS objectAtIndex:0]]]];
NSString *docDir = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSLog(#"saving jpg");
NSString *jpgFilePath = [NSString stringWithFormat:#"%#/%#.jpg",docDir,[self.NameArray objectAtIndex:0]];
NSData *data2 = [NSData dataWithData:UIImageJPEGRepresentation(image, 1.0f)];//1.0f = 100% quality
[data2 writeToFile:jpgFilePath atomically:YES];
and i am getting the image via
NSString *docDir = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSString *jpgFilePath = [NSString stringWithFormat:#"%#/%#.jpg",docDir,[self.NameArray objectAtIndex:[indexPath row]]];
UIImage *image = [UIImage imageNamed:jpgFilePath];
Any help ?
Thanks
Change the last line of your code to
UIImage *image = [UIImage imageWithContentsOfFile:jpgFilePath];
UIImage's +imageNamed: searches the app bundle for a file with a given name, which is not what you need.
I am using a UIImagePickerController in my application.
After selecting an image by user,
image should be saved at application Documents Directory,
my Code is Give Below.
-(void)imagePickerController:(UIImagePickerController*)picker didFinishPickingMediaWithInfo:(NSDictionary*)info
{
[picker dismissModalViewControllerAnimated:YES];
NSData *imgData = UIImagePNGRepresentation([info objectForKey:#"UIImagePickerControllerOriginalImage"]);
UIImage *img = [[UIImage alloc] initWithData:imgData];
stuImgView.image = img;
[img release];
//write image
NSString *imageFilename = [NSString stringWithFormat:#"%i.jpg", currentStudent.stuNo];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *path = [NSString stringWithFormat:#"%#/%#", [paths objectAtIndex:0], imageFilename];
UIImage *stuImg;
BOOL success;
NSFileManager *fm=[NSFileManager defaultManager];
// how to store file at documents dir????
}
i dont know how to use file manager to store a file?
Help me Out.
Thanks in advance.
You can use writeToFile:atomically::
[imgData writeToFile:path atomically:NO];