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    <p>It's dangerous to use the fullResolutionImage for this task for several reasons. Some remarks:</p> <ol> <li>For large images memory problems could occur. when using the fullResolutionImage method. Please note, that the Photo-Library (on the iPad at least) can also contain RAW-images.</li> <li>The performance is suboptimal as internally from the imagefile ImageIO creates first a CGImageRef that is then converted to a JPEG. This takes time.</li> <li>The AssetLibrary can also contain videos. In such a case fullResolutionImage only returns a previewImage of the video, but not the actual video.</li> <li>It's no problem to store the actual Asset-Objects as these are small in memory. </li> </ol> <p>A far better approach to write out the images to the documents directory, would be to use the getBytes method of ALAssetsRepresentation. This should be way faster and more efficient memory wise. It also gives you the original image file (incl. metadata) and also works for videos.</p> <p>Your example code rewritten then would look like that:</p> <pre><code>//reading out the orginal images for (int j=0; j&lt;[assetArray count]; j++) { ALAssetRepresentation *representation = [[assetArray objectAtIndex:j] defaultRepresentation]; NSString* filename = [documentPath stringByAppendingPathComponent:[representation filename]]; [[NSFileManager defaultManager] createFileAtPath:filename contents:nil attributes:nil]; NSOutputStream *outPutStream = [NSOutputStream outputStreamToFileAtPath:filename append:YES]; [outPutStream open]; long long offset = 0; long long bytesRead = 0; NSError *error; uint8_t * buffer = malloc(131072); while (offset&lt;[representation size] &amp;&amp; [outPutStream hasSpaceAvailable]) { bytesRead = [representation getBytes:buffer fromOffset:offset length:131072 error:&amp;error]; [outPutStream write:buffer maxLength:bytesRead]; offset = offset+bytesRead; } [outPutStream close]; free(buffer); } //reading out the fullScreenImages and thumbnails for (int j=0; j&lt;[assetArray count]; j++) { @autoreleasepool { ALAsset *asset = [assetArray objectAtIndex:j]; NSString *orgFilename = [representation filename]; NSString *filenameFullScreen = [NSString stringWithFormat:@"%@_fullscreen.png",[orgFilename stringByDeletingPathExtension]] NSString* pathFullScreen = [documentPath stringByAppendingPathComponent:filenameFullScreen]; CGImageRef imageRefFullScreen = [[asset defaultRepresentation] fullScreenImage]; UIImage *imageFullScreen = [UIImage imageWithCGImage:imageRefFullScreen]; NSData *imageDataFullScreen = UIImagePNGRepresentation(imageFullScreen); [imageDataFullScreen writeToFile:pathFullScreen atomically:YES]; NSString *filenameThumb = [NSString stringWithFormat:@"%@_thumb.png",[orgFilename stringByDeletingPathExtension]] NSString* pathThumb = [documentPath stringByAppendingPathComponent:filenameThumb]; CGImageRef imageRefThumb = [asset thumbnail]; UIImage *imageThumb = [UIImage imageWithCGImage:imageRefThumb]; NSData *imageDataThumb = UIImagePNGRepresentation(imageThumb); [imageDataThumb writeToFile:pathThumb atomically:YES]; } } </code></pre>
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    1. POWhat is the correct way to import & save Photos from iPhone Album?
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    1. COthank you its working very nicely.. But how can I copy the thumbnail image and fullscreen image to the documents folder ? or is there is anyother way for getting these images from the ALAssetsRepresentation in the documents folder ?
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    2. COI amended the source code to include reading out the fullScreenImage and thumbnail. For these 2 images you can use the approach you had before-as they are limited in size and consume only a predictable amount of memory in contrast to the fullResolutionImage. Depending on what you want to do you might consider saving the fullScreenImage as JPEG instead of PNG, but this is only a minor code change.
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    3. COthanks for your answer.. Its working well :)
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