ios - 从图像Objective c中提取纬度和经度

Question

我在从图像(具有地理位置详细信息)获取纬度和经度数据时遇到问题。我已经导入了 EXIF 框架，并使用以下代码来实现:

 NSData *jpegData = [UIImageJPEGRepresentation(image, 0.5) base64String];
EXFJpeg* jpegScanner = [[EXFJpeg alloc] init];
[jpegScanner scanImageData: jpegData];
EXFMetaData* exifData = jpegScanner.exifMetaData;
id latitudeValue = [exifData tagValue:[NSNumber numberWithInt:EXIF_GPSLatitude]];
id longitudeValue = [exifData tagValue:[NSNumber numberWithInt:EXIF_GPSLongitude]];
NSLog(@"Longitude: %@  Longitude: %@", latitudeValue, longitudeValue);

但是它返回纬度和经度的 NULL 值，任何人都可以告诉我我在上面的代码中做错了什么吗？请帮帮我。提前致谢!!

Answer 1

您可以使用 alasset 来做到这一点框架。

ALAssetsLibrary *assetsLibrary = [[ALAssetsLibrary alloc]init];
[assetsLibrary assetForURL:photoUrl resultBlock:resultBlock failureBlock:nil];
ALAssetsLibraryAssetForURLResultBlock resultBlock = ^(ALAsset *photoAsset) {        
    CLLocation *location = [photoAsset valueForProperty:ALAssetPropertyLocation];

    NSMutableDictionary *exifDataDict = [[NSMutableDictionary alloc] init];
    if (location != nil) {
        [exifDataDict setObject:[NSNumber numberWithDouble:location.coordinate.latitude] forKey:@"latitude"];
        [exifDataDict setObject:[NSNumber numberWithDouble:location.coordinate.longitude] forKey:@"longitude"];
    }
}