I am writing an image in iPad using ALAssets. When it finish I try to create an UIImage with the returned URL but it won't load. This is the code:
LAssetsLibrary *library = [[ALAssetsLibrary alloc] init];
[library writeImageToSavedPhotosAlbum:[anImage CGImage] orientation:(ALAssetOrientation)[anImage imageOrientation] completionBlock:^(NSURL *assetURL, NSError *error){
if (!error) {
CGImageSourceRef src = CGImageSourceCreateWithURL((CFURLRef) [NSURL fileURLWithPath:[assetURL absoluteString]], NULL);
My purpose is to save an image to the device, then convert it to another format using ImageIO and finally send it to a web service. CGImageSourceRef is null, I also tried with standard UIImage with the same result.
What I am doing wrong here?
EDIT: The problem is when creating the CFURLRef.
If I do
CGImageSourceCreateWithURL((CFURLRef) assetURL, NULL);
I got this error
ImageIO: CGImageSourceCreateWithURL CFURLCreateDataAndPropertiesFromResource failed with error code -11.
But if I try to convert the URL with
[NSURL fileURLWithPath:[assetURL absoluteString]]
the path is changed to
assets-library:/asset/asset.JPG%3Fid=57BBBA99-E7BF-4DB7-839E-F915005E6DFA&ext=JPG -- file://localhost/
I cannot find how to properly create the CFURLRef needed by the method. I tried printing all the conversions I could think of and this are the results
[assetURL relativePath]
[assetURL relativeString]
[assetURL absoluteURL]
[assetURL absoluteString]
/asset.JPG ,
assets-library://asset/asset.JPG?id=57BBBA99-E7BF-4DB7-839E-F915005E6DFA&ext=JPG
assets-library://asset/asset.JPG?id=57BBBA99-E7BF-4DB7-839E-F915005E6DFA&ext=JPG
assets-library://asset/asset.JPG?id=57BBBA99-E7BF-4DB7-839E-F915005E6DFA&ext=JPG
[NSURL fileURLWithPath:[assetURL relativePath]]
[NSURL fileURLWithPath:[assetURL relativeString]]
[NSURL fileURLWithPath:[assetURL absoluteString]]
file://localhost/asset.JPG
assets-library:/asset/asset.JPG%3Fid=57BBBA99-E7BF-4DB7-839E-F915005E6DFA&ext=JPG -- file://localhost/
assets-library:/asset/asset.JPG%3Fid=57BBBA99-E7BF-4DB7-839E-F915005E6DFA&ext=JPG -- file://localhost/
Help please, I am stuck with this :-(
This is what I did for my case.
UIImage* anImage; //this is the original image
NSData * imgData = UIImageJPEGRepresentation(anImage, 0.7);
CGImageSourceRef src = CGImageSourceCreateWithData((CFDataRef) imgData, NULL);
NSMutableData *data = [NSMutableData data];
CFStringRef imageType = CFSTR("com.microsoft.bmp");
CGImageDestinationRef myImageDest = CGImageDestinationCreateWithData((CFMutableDataRef) data, imageType, 1, nil);
//Convert!
CGImageDestinationAddImageFromSource(myImageDest, src, 0, myOptions);
CGImageDestinationFinalize(myImageDest);
//Freeing things
CFRelease(myImageDest);
CFRelease(src);
But this just converts the image, it doesn't store it in any file... Not sure this should be an answer to the original question.
If you already have an ALAsset and your goal is a CGImageRef you can do something like this.
ALAssetRepresentation* rep = [asset defaultRepresentation];
NSDictionary* options = [[NSDictionary alloc] initWithObjectsAndKeys:
(id)kCFBooleanTrue, (id)kCGImageSourceCreateThumbnailWithTransform,
(id)kCFBooleanTrue, (id)kCGImageSourceCreateThumbnailFromImageAlways,
(id)[NSNumber numberWithDouble:400], (id)kCGImageSourceThumbnailMaxPixelSize,
nil];
CGImageRef image = [rep CGImageWithOptions:options];
Related
When using ALAssetsLibrary, I used to save image to photo library with proper exif using the code below:
NSInteger orientation = 2;// Or whatever
NSData *jpegData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageDataSampleBuffer];
CMSetAttachment(imageDataSampleBuffer, kCGImagePropertyOrientation,
[NSNumber numberWithInt: orientation],
kCMAttachmentMode_ShouldPropagate);
ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];
CFDictionaryRef attachments = CMCopyDictionaryOfAttachments(kCFAllocatorDefault, imageDataSampleBuffer, kCMAttachmentMode_ShouldPropagate);
[library writeImageDataToSavedPhotosAlbum:jpegData metadata:(id)attachments completionBlock:^(NSURL *assetURL, NSError *error) {
...
...
}
It's not clear how to translate that code when using PHPhotoLibrary. Can anyone provide the right way to save attachments along with the jpeg image?
Use ImageIO to add Metadata to your JPEG/PNG image as described in the following article:
Save the exif metadata using the new PHPhotoLibrary
I have been trying to extract metadata information from a .mp3 file for an iPhone app. I tried using AVAsset like this.It didn't work,the common meta data is empty. But audacity and another iOS app from app store could retrieve the meta data details. I don't know why?.
So, I tried to extract the same with below code using AudioToolBox framework
CFDictionaryRef piDict = nil;
UInt32 piDataSize = sizeof(piDict);
// Populates a CFDictionary with the ID3 tag properties
err = AudioFileGetProperty(fileID, kAudioFilePropertyInfoDictionary, &piDataSize, &piDict);
if(err != noErr) {
NSLog(#"AudioFileGetProperty failed for property info dictionary");
return nil;
}
// Toll free bridge the CFDictionary so that we can interact with it via objc
NSMutableDictionary* nsDict = [(__bridge NSDictionary*)piDict mutableCopy];
This returned everything except album art. When I tried to extract the album art using kAudioFilePropertyAlbumArtwork , I got osstatus error(The operation couldn't be completed).
So at last, I tried my luck with ObjC wrapper for libId3(found here). It worked perfectly well. I could get the artwork.
My question is, why AVAsset could not retrieve the data?. What am I missing there?. somebody managed to to get it work?. A sample will be appreciated.
Why kAudioFilePropertyAlbumArtwork extraction couldn't be completed?. Both the issues happened with all the .mp3 files I had.
Solution Update:
AVAsset didn't work for me because I made my URL using
[NSURL URLWithString:[filePath stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]]
rather than
NSURL *fileURL = [NSURL fileURLWithPath:filePath];
To use AVAsset to extract metadata informations, this post is useful. The following code is what you need:
NSString *filePath = [[NSBundle mainBundle] pathForResource:#"filename" ofType:#"mp3"];
NSURL *fileURL = [NSURL fileURLWithPath:filePath];
AVAsset *asset = [AVURLAsset URLAssetWithURL:fileURL options:nil];
NSArray *keys = [NSArray arrayWithObjects:#"commonMetadata", nil];
[asset loadValuesAsynchronouslyForKeys:keys completionHandler:^{
NSArray *artworks = [AVMetadataItem metadataItemsFromArray:asset.commonMetadata
withKey:AVMetadataCommonKeyArtwork
keySpace:AVMetadataKeySpaceCommon];
for (AVMetadataItem *item in artworks) {
if ([item.keySpace isEqualToString:AVMetadataKeySpaceID3]) {
NSDictionary *dict = [item.value copyWithZone:nil];
self.imageView.image = [UIImage imageWithData:[dict objectForKey:#"data"]];
} else if ([item.keySpace isEqualToString:AVMetadataKeySpaceiTunes]) {
self.imageView.image = [UIImage imageWithData:[item.value copyWithZone:nil]];
}
}
}];
NSURL *fileURL1 = [NSURL fileURLWithPath:url];
AVAsset *asset = [AVAsset assetWithURL:fileURL1];
for (AVMetadataItem *metadataItem in asset.commonMetadata) {
if ([metadataItem.commonKey isEqualToString:#"artwork"]){
NSDictionary *imageDataDictionary = (NSDictionary *)metadataItem.value;
NSData *imageData = [imageDataDictionary objectForKey:#"data"];
UIImage *image = [UIImage imageWithData:imageData];
imageThumb.image = image;
}
}
I wish to compress the image before storing it as an NSData object.
Below is the code, that helps me take NSData object of an Image.
NSURL *referenceURL = [info objectForKey:UIImagePickerControllerReferenceURL];
ALAssetsLibrary *library1 = [[ALAssetsLibrary alloc] init];
[library1 assetForURL:referenceURL resultBlock:^(ALAsset *asset)
{
int byteArraySize = asset.defaultRepresentation.size;
NSMutableData* rawData = [[NSMutableData alloc]initWithCapacity:byteArraySize];
void* bufferPointer = [rawData mutableBytes];
NSError* error=nil;
[asset.defaultRepresentation getBytes:bufferPointer fromOffset:0 length:byteArraySize error:&error];
if (error) {
NSLog(#"%#",error);
}
rawData = [NSMutableData dataWithBytes:bufferPointer length:byteArraySize];
}
Any Help will be appreciated.
UIImagePickerController does return a compressed image, but you can control the format and compression as well with this built in UIKit function and a related function for PNGs:
NSData* UIImageJPEGRepresentation(UIImage *image, CGFloat compressionQuality);
You might need to create an NSURL if referenceURL returns a string.
NSImage *image = [UIImage imageWithData:[NSData dataWithContentsOfURL: referenceURL]];
NSData *compressedImage = UIImageJPEGRepresentation(image, .1); //.1 is low quality
If you're using a UIImagePickerController, the image returned will be a JPEG, which is already compressed (I think). If not, you can use AVAssetWriter to write the image as a JPEG or PNG.
simple to use:-
-(UIImage *)fireYourImageForCompression:(UIImage *)imgComing{
NSData *dataImgBefore = [[NSData alloc] initWithData:UIImageJPEGRepresentation((imgComing), 1.0)];//.1 BEFORE COMPRESSION
int imageSizeBefore = (int)dataImgBefore.length;
NSLog(#"SIZE OF IMAGE: %i ", imageSizeBefore);
NSLog(#"SIZE OF IMAGE in Kb: %i ", imageSizeBefore/1024);
NSData *dataCompressedImage = UIImageJPEGRepresentation(imgComing, .1); //.1 is low quality
int sizeCompressedImage = (int)dataCompressedImage.length;
NSLog(#"SIZE AFTER COMPRESSION OF IMAGE: %i ", sizeCompressedImage);
NSLog(#"SIZE AFTER COMPRESSION OF IMAGE in Kb: %i ", sizeCompressedImage/1024); //AFTER
//now change your image from compressed data
imgComing = [UIImage imageWithData:dataCompressedImage];
return imgComing;}
I have code that will check to see if an image is on the phone or not (the name being retrieved from the db), and if not, it runs this code:
NSString *urlString = [NSString stringWithFormat: #"http://www.vegashipster.com/%#",image_path];
NSData *imageData = [[NSData alloc] initWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:urlString]]];
NSLog(#"saving jpg");
UIImage *image = [[UIImage alloc] initWithData:imageData];//1.0f = 100% quality
[UIImageJPEGRepresentation(image, 1.0f) writeToFile:myFilePath atomically:YES];
NSLog(#"saving image done");
NSLog(#"URL String: %#",urlString);
NSLog(#"http://www.vegashipster.com/%#",image_path);
rest_image = [UIImage imageNamed:image_path];
[image release];
[imageData release];
This code works just fine on the simulator, but on the iPhone, the screen freezes for a few seconds (downloading the image, I think), then loads the page, but with no image visible. The next time you hit that page, there is no freeze. So I believe the file is being created, but it's a messed up image file, and therefore not displayed.
I've already broken this code up so that it runs in it's own thread, and again, it works in the simulator. I had thought that if it ran behind the scenes, there would be less of a chance that the image data would get messed up, but the exact same thing happens (minus the freezing). Does anyone know what I am doing wrong with this code? Thanks for any and all help/comments.
Edit
And yes, the images being downloaded are strictly .jpg
Edit 2
I seen:
Make sure you are writing to your DOCUMENTS directory, which you have read+write access to. Otherwise you won't get any files.
at http://www.iphonedevsdk.com/forum/iphone-sdk-development/15628-file-weirdness-files-written-disk-do-not-appear-nsfilemanager-defaultmanager.html . Could this be my issue?
NSString *image_path = [[NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 5)] stringByReplacingOccurrencesOfString:#"../"
NSString *myFilePath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:image_path];
Last Edit
Well, I found what I believe to be my answer at How can I get a writable path on the iPhone? . It pretty much states I cannot save image files where my own image files are located inside the build. If this is incorrect, please let me know and I will try your way.
NSData *imageData = [[NSData alloc] initWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:urlString]]];
Is a synchronous call, ie it blocks until it has fully executed, which in the case of network operations can be 1 second, 10 seconds or 3 minutes if you don't have a time out. You are presumably running this on the main thread which is why your UI freezes (all UI stuff is done on the main thread so you must do everything not to block it). The reason it doesn't freeze the next time around is probably that it has cached the image data.
You should use asynchronous APIs, NSURLConnection has some, however I strongly recommend ASIHTTPRequest, which is an obj c wrapper around NSURLConnection and co. The code would look something like this (read through the how to use section)
- (IBAction)grabURLInBackground:(id)sender
{
NSURL *url = [NSURL URLWithString:#"http://allseeing-i.com"];
ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:url];
[request setDelegate:self];
[request startAsynchronous];
}
- (void)requestFinished:(ASIHTTPRequest *)request
{
// Use when fetching text data
NSString *responseString = [request responseString];
// Use when fetching binary data
NSData *responseData = [request responseData];
UIImage* downloadedImage = [UIImage imageWithData:responseData];
}
- (void)requestFailed:(ASIHTTPRequest *)request
{
NSError *error = [request error];
}
Sorry, forgot about this thread completely. I did end up fixing this issue. Here is what I did:
NSFileManager* fileManager = [NSFileManager defaultManager];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES);
NSString *libraryDirectory = [paths objectAtIndex:0];
NSString *myFilePath = [libraryDirectory stringByAppendingPathComponent:image_path];
BOOL fileExists = [fileManager fileExistsAtPath:myFilePath];
if (fileExists){
hotel_image = [UIImage imageWithContentsOfFile:myFilePath];
}else{
[NSThread detachNewThreadSelector:#selector(downloadImage:) toTarget:[HotelsDetailsViewController class] withObject:image_path];
fileExists = [fileManager fileExistsAtPath:myFilePath];
if (fileExists){
hotel_image = [UIImage imageWithContentsOfFile:myFilePath];
}else{
hotel_image = [UIImage imageNamed:#"hdrHotels.jpg"];
}
}
In short, I found my app's library directory and saved there.
I'm creating some temporary files in the iPad simulator. To test my file creation, I create the file and then read it back. Here's some code to show this:
-(NSString *) writeToTempFile:(UIImage*) image{
NSString *path = [self createTemporaryFile];
NSLog(#"path: %#", path);
NSData *data = UIImageJPEGRepresentation(image, 1);
[data writeToFile:path atomically:YES];
free(data);
return path;
}
-(UIImage *) readTempFile:(NSString *) path{
NSData *data = [[NSData alloc] initWithContentsOfFile:path];
UIImage *image = [[UIImage alloc] initWithData:data];
return image;
}
I call these methods one after another, before a final function writes out the UIImage to the photo album.
UIImageWriteToSavedPhotosAlbum(image2, self, nil, nil);
The problem is, this always crashes my app on the third time it is executed. First and second time it successfully does all of this and stores to the album. Third time it crashes to Home. Any ideas?
NSData *data = UIImageJPEGRepresentation(image, 1);
[data writeToFile:path atomically:YES];
free(data);
The NSData returned from UIImageJPEGRepresentation is -autoreleased. There is no need to free() it. And it is wrong to free() any Objective-C objects — send a -release message instead.
Please read through the Memory Management Programming Guide.