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iOS如何扫描HEIF格式的二维码图片

2019-10-21 18:41:36
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一、说在前面

iPhone 7 之后系统相机支持HEIF格式的图片,在扫描二维码时,该格式的图片需要转换成JPG格式才能进行扫描成功。

二、思路

用户在打开系统相册选择完一张照片后,要判断该照片是否是HEIF格式,如果是,进行格式转换之后再扫描JPG图片的内容,得到扫描结果。

三、具体实现

因为过程中用到photoKit,因此需要加入该头文件,#import

@protocol TVUImageManagerDelegate <NSObject>- (void)letQRCodeVCScanQRCodeImageInAlbum:(BOOL)isHEIFFormat;@end@interface TVUImageManager : NSObject@property (strong, nonatomic) UIImage *jpgImage;@property (strong, nonatomic) UIImage *selectedImage;@property (strong, nonatomic) PHAsset *selectedAsset;@property (nonatomic,strong) id <TVUImageManagerDelegate> delegate;+ (TVUImageManager *)defaultManager;- (void)doSomethingAfterSelectedImage:(NSDictionary *)info;@end

自定义类:(.mm)

#define IOS9orLater ([UIDevice currentDevice].systemVersion.integerValue >= 9)@implementation TVUImageManager#pragma mark - init part+ (TVUImageManager *)defaultManager{  static TVUImageManager *m_manager = nil;  if (m_manager == nil) {    m_manager = [[TVUImageManager alloc] init];  }  return m_manager;}- (id)init{  self = [super init];  if (self) {  }  return self;}#pragma mark - image format part- (void)doSomethingAfterSelectedImage:(NSDictionary *)info{  [self getSelectedImagePHAsset:info];  if (self.selectedAsset == nil) {    log4cplus_error("TVUImageManagerLog", "%s:selected image is null",__func__);    return;  }else {    BOOL isHEIF = [self judgeIfAnImageIsHeifFormat];    if (isHEIF) {      log4cplus_error("TVUImageManagerLog", "%s:selected image is HEIF format",__func__);      [self convertImageFormatFromHeifToJpegAndThenScanTheImage];    }else {      log4cplus_error("TVUImageManagerLog", "%s:selected image is not HEIF format",__func__);      self.selectedImage = (UIImage *)[info objectForKey:UIImagePickerControllerOriginalImage];      if (self.selectedImage == nil) {        log4cplus_error("TVUImageManagerLog", "%s:selected image is null",__func__);        return;      }      [self.delegate letQRCodeVCScanQRCodeImageInAlbum:NO];    }  }}// Choose a picture from the system album- (void)getSelectedImagePHAsset:(NSDictionary *)info{  log4cplus_error("TVUImageManagerLog", "%s:get selected image PHAsset",__func__);  NSURL *imageAssetUrl = [info objectForKey:UIImagePickerControllerReferenceURL];  PHFetchResult *fetchResult = [PHAsset fetchAssetsWithALAssetURLs:[NSArray arrayWithObject:imageAssetUrl] options:nil];  if (fetchResult.count == 0) {    log4cplus_error("TVUImageManagerLog", "%s:fetchResult's count is 0",__func__);    return;  }  self.selectedAsset = (PHAsset*)fetchResult.firstObject;}// Determine if the picture is in HEIF format- (BOOL)judgeIfAnImageIsHeifFormat{  log4cplus_error("TVUImageManagerLog", "%s:begin to judge if an image is HEIF format",__func__);  __block BOOL isHEIF = NO;  if (IOS9orLater) {    NSArray *resourceList = (NSArray *)[PHAssetResource assetResourcesForAsset:self.selectedAsset];    [resourceList enumerateObjectsUsingBlock:^(id _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {      PHAssetResource *resource = obj;      NSString *UTI = resource.uniformTypeIdentifier;      if ([UTI isEqualToString:@"public.heif"] || [UTI isEqualToString:@"public.heic"]) {        isHEIF = YES;        *stop = YES;      }    }];  }else {    NSString *UTI = [self.selectedAsset valueForKey:@"uniformTypeIdentifier"];    isHEIF = [UTI isEqualToString:@"public.heif"] || [UTI isEqualToString:@"public.heic"];  }  return isHEIF;}// Convert image format from HEIF to JPEG and then scan the image- (void)convertImageFormatFromHeifToJpegAndThenScanTheImage{  log4cplus_error("TVUImageManagerLog", "%s:begin to convert image format from HEIF to JPEG",__func__);  [[PHImageManager defaultManager] requestImageDataForAsset:self.selectedAsset options:nil resultHandler:^(NSData * _Nullable imageData, NSString * _Nullable dataUTI, UIImageOrientation orientation, NSDictionary * _Nullable info) {    CIImage *ciImage = [CIImage imageWithData:imageData];    CIContext *context = [CIContext context];    NSData *jpgData = [context JPEGRepresentationOfImage:ciImage colorSpace:ciImage.colorSpace options:@{}];    self.jpgImage = [UIImage imageWithData:jpgData];    [self.delegate letQRCodeVCScanQRCodeImageInAlbum:YES];  }];}@end

调用:

#pragma mark UIImagePickerControllerDelegate- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{  [self.imageMgr doSomethingAfterSelectedImage:info];}

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持VEVB武林网。


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