從圖像獲取「時間戳」

Question

我只是想知道是否有獲取圖片時間戳的方法，或者如果該信息甚至被寫入圖像文件，例如從何時拍攝。

在此先感謝

Answer 1

導入imageIO框架並嘗試使用帶有時間戳的圖像。這裏是one，將它添加到您的項目中。

#import <ImageIO/ImageIO.h> 

NSString *path = [[NSBundle mainBundle] pathForResource:@"gg_gps" ofType:@"jpg"]; 
NSURL *imageFileURL = [NSURL fileURLWithPath:path]; 
CGImageSourceRef imageSource = CGImageSourceCreateWithURL((CFURLRef)CFBridgingRetain(imageFileURL), NULL); 

// or you can get your imageSource this other way: 
// NSData *data = [NSData dataWithContentsOfFile:path]; 
// CGImageSourceRef imageSource = CGImageSourceCreateWithData((__bridge CFDataRef)data, NULL); 

NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:[NSNumber numberWithBool:NO], (NSString *)kCGImageSourceShouldCache, nil]; 
CFDictionaryRef imageProperties = CGImageSourceCopyPropertiesAtIndex(imageSource, 0, (CFDictionaryRef)CFBridgingRetain(options)); 
CFDictionaryRef exifDic = CFDictionaryGetValue(imageProperties, kCGImagePropertyExifDictionary); 
if (exifDic){ 
    NSString *timestamp = (NSString *)CFBridgingRelease(CFDictionaryGetValue(exifDic, kCGImagePropertyExifDateTimeOriginal)); 
    if (timestamp){ 
     NSLog(@"timestamp: %@", timestamp); 
    } else { 
     NSLog(@"timestamp not found in the exif dic %@", exifDic); 
    } 
} else { 
    NSLog(@"exifDic nil for imageProperties %@",imageProperties); 
} 
CFRelease(imageProperties);