//获取gif图片的总时长和循环次数
- (NSTimeInterval)durationForGifData:(NSData *)data{
//将GIF图片转换成对应的图片源
CGImageSourceRef gifSource = CGImageSourceCreateWithData((__bridge CFDataRef)data, NULL);
//获取其中图片源个数,即由多少帧图片组成
size_t frameCout = CGImageSourceGetCount(gifSource);
//定义数组存储拆分出来的图片
NSMutableArray* frames = [[NSMutableArray alloc] init];
NSTimeInterval totalDuration = 0;
for (size_t i=0; i<frameCout; i++) {
//从GIF图片中取出源图片
CGImageRef imageRef = CGImageSourceCreateImageAtIndex(gifSource, i, NULL);
//将图片源转换成UIimageView能使用的图片源
UIImage* imageName = [UIImage imageWithCGImage:imageRef];
//将图片加入数组中
[frames addObject:imageName];
NSTimeInterval duration = [self gifImageDeleyTime:gifSource index:i];
totalDuration += duration;
CGImageRelease(imageRef);
}
//获取循环次数
NSInteger loopCount;//循环次数
CFDictionaryRef properties = CGImageSourceCopyProperties(gifSource, NULL);
if (properties) {
CFDictionaryRef gif = CFDictionaryGetValue(properties, kCGImagePropertyGIFDictionary);
if (gif) {
CFTypeRef loop = CFDictionaryGetValue(gif, kCGImagePropertyGIFLoopCount);
if (loop) {
//如果loop == NULL,表示不循环播放,当loopCount == 0时,表示无限循环;
CFNumberGetValue(loop, kCFNumberNSIntegerType, &loopCount)
};
}
}
CFRelease(gifSource);
return totalDuration;
}
循环次数的键:kCGImagePropertyGIFLoopCount
时间间隔的键:kCGImagePropertyGIFUnclampedDelayTime
//获取GIF图片每帧的时长
- (NSTimeInterval)gifImageDeleyTime:(CGImageSourceRef)imageSource index:(NSInteger)index {
NSTimeInterval duration = 0;
CFDictionaryRef imageProperties = CGImageSourceCopyPropertiesAtIndex(imageSource, index, NULL);
if (imageProperties) {
CFDictionaryRef gifProperties;
BOOL result = CFDictionaryGetValueIfPresent(imageProperties, kCGImagePropertyGIFDictionary, (const void **)&gifProperties);
if (result) {
const void *durationValue;
if (CFDictionaryGetValueIfPresent(gifProperties, kCGImagePropertyGIFUnclampedDelayTime, &durationValue)) {
duration = [(__bridge NSNumber *)durationValue doubleValue];
if (duration < 0) {
if (CFDictionaryGetValueIfPresent(gifProperties, kCGImagePropertyGIFDelayTime, &durationValue)) {
duration = [(__bridge NSNumber *)durationValue doubleValue];
}
}
}
}
}
return duration;
}