Simple version record of GIF in iOS

I have done an app about gif before, and I have never had time to record it. Now I want to record the learning process.

Creating a gif is based on ImageIO. framework. Therefore, you must add this library first.

 

Gif decomposed Image

 

 

-(Void) viewDidLoad {[super viewDidLoad]; NSData * data = [NSData dataWithContentsOfFile: [[NSBundle mainBundle] pathForResource: @ test101 ofType: @ gif]; // obtain the image data source CGImageSourceRef source = CGImageSourceCreateWithData (_ bridge CFDataRef) data, NULL) through data; // obtain the number of frames size_t count = CGImageSourceGetCount (source ); NSMutableArray * tmpArray = [NSMutableArray array]; for (size_t I = 0; I <count; I ++) {// obtain the image CGImageRef imageRef = CGImageSourceCreateImageAtIndex (source, I, NULL); // generate image UIImage * image = [UIImage imageWithCGImage: imageRef scale: [UIScreen mainScreen]. scale orientation: UIImageOrientationUp]; [tmpArray addObject: image]; CGImageRelease (imageRef);} CFRelease (source); int I = 0; for (UIImage * img in tmpArray) {// Write File NSData * imageData = UIImagePNGRepresentation (img); NSString * pathNum = [[self backPath] stringByAppendingPathComponent: [NSString stringWithFormat: @ % d.png, I]; [imageData writeToFile: pathNum atomically: NO]; I ++ }}// return the path to save the image-(NSString *) backPath {NSFileManager * fileManager = [NSFileManager defamanager]; NSString * path = [UniversalMethod backDocumentDirectoryPath]; NSString * imageDirectory = [path stringByAppendingPathComponent: @ Normal]; [fileManager createDirectoryAtPath: imageDirectory succeeded: YES attributes: nil error: nil]; return imageDirectory ;}

 

Gif Production

To create a gif, you must rely on MobileCoreServices. framework.

 

 

// Gif preparation // obtain the source data image NSMutableArray * imgs = [[NSMutableArray alloc] initWithObjects: [UIImage imageNamed: @ bear_1], [UIImage imageNamed: @ bear_2], nil]; // Image Target CGImageDestinationRef destination; // create the output path NSArray * document = NSSearchPathForDirectoriesInDomains (NSDocumentDirectory, NSUserDomainMask, YES); NSString * documentStr = [document objectAtIndex: 0]; NSFileManager * fileManager = [NSFileManager defaultManager]; NSString * textDirectory = [documentStr stringByAppendingPathComponent: @ gif]; [fileManager createDirectoryAtPath: textDirectory succeeded: YES attributes: nil error: nil]; NSString * path = [textDirectory stringByAppendingPathComponent: @test101.gif]; NSLog (@%@, path); // create a CFURL object/* struct (CFAllocatorRef allocator, CFStringRef filePath, CFURLPathStyle pathStyle, boolean isDirectory) allocator: distributor. Generally, kCFAllocatorDefault filePath: path pathStyle: path style is used. Fill in kCFURLPOSIXPathStyle. For more information, see "isDirectory" by yourself, used to specify whether filePath is resolved as a directory path */CFURLRef url = CFURLCreateWithFileSystemPath (kCFAllocatorDefault, (CFStringRef) path, kCFURLPOSIXPathStyle, false ); // return the image destination = CGImageDestinationCreateWithURL (url, kUTTypeGIF, imgs. count, NULL); // set gif information, playback interval, basic data, and delay time NSDictionary * frameProperties = [NSDictionary dictionaryWithObject: [NSMutableDictionary category: [NSNumber numberWithFloat: 0.3], (NSString *) delimiter, nil] forKey :( NSString *) delimiter]; // set the gif information NSMutableDictionary * dict = [NSMutableDictionary dictionaryWithCapacity: 2]; [dict setObject: [NSNumber numberWithBool: YES] forKey :( NSString *) delimiter]; [dict setObject :( NSString *) delimiter forKey :( NSString *) kCGImagePropertyColorModel]; [dict setObject: [NSNumber numberWithInt: 8] forKey :( NSString *) kCGImagePropertyDepth]; [dict setObject: [NSNumber numberWithInt: 0] forKey :( NSString *) random]; NSDictionary * gifProperties = [NSDictionary dictionaryWithObject: dict forKey :( NSString *) kCGImagePropertyGIFDictionary]; // synthesize gif for (UIImage * dImg in imgs) {CGImageDestinationAddImage (destination, dImg. CGImage, (_ bridge CFDictionaryRef) frameProperties);} CGImageDestinationSetProperties (destination, (_ bridge CFDictionaryRef) gifProperties); CGImageDestinationFinalize (destination); CFRelease (destination );