美文网首页
iOS 图片选择 heic 格式图片转 jpg

iOS 图片选择 heic 格式图片转 jpg

作者: IT姑凉 | 来源:发表于2019-11-25 18:24 被阅读0次

    iOS HEIF/HEVC 格式

    iOS 11更新后,iPhone 7及以上设备,在拍摄照片时的默认图像存储格式是 .heic.heic 格式相比普通的jpg、png格式来说,占用手机的内存更小,而且拍摄下来的照片无损度也非常高,这也就是为什么iOS 11会采用这种文件的原因。如下图:

    修改相机格式操作截图:


    详见:
    1、关于 iOS 11 更新
    https://support.apple.com/zh-cn/HT208067#11
    2、在 Apple 设备上使用 HEIF 或 HEVC 媒体
    https://support.apple.com/zh-cn/HT207022

    遇到的问题

    APP在图片选择的时候,无法显示图片,需要 heic 格式图片转 jpg 才能显示
    插件:cordova-plugin-mediapicker-dmcsdk

    1、识别HEIF
    __block BOOL isHEIF = NO;
    if (iOSVersionGreaterThanOrEqualTo(@"9.0")) {
        NSArray *resourceList = [PHAssetResource assetResourcesForAsset:phAsset];
        [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 = [phAsset valueForKey:@"uniformTypeIdentifier"];
        isHEIF = [UTI isEqualToString:@"public.heif"] || [UTI isEqualToString:@"public.heic"];
    }
    
    2、转换
    [[PHImageManager defaultManager] requestImageDataForAsset:phAsset options:nil resultHandler:^(NSData * _Nullable imageData, NSString * _Nullable dataUTI, UIImageOrientation orientation, NSDictionary * _Nullable info) {
        if (isHEIF) {
            CIImage *ciImage = [CIImage imageWithData:imageData];
            CIContext *context = [CIContext context];
            NSData *jpgData = [context JPEGRepresentationOfImage:ciImage colorSpace:ciImage.colorSpace options:@{}];
        } else {
        }
    }];
    
    3、修改插件源码
    #define iOSVersionGreaterThanOrEqualTo(v)([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch]!=NSOrderedAscending)
    
    ...
    
    [[PHImageManager defaultManager] requestImageDataForAsset:asset  options:options resultHandler:^(NSData * _Nullable imageData, NSString * _Nullable dataUTI, UIImageOrientation orientation, NSDictionary * _Nullable info) {
        NSString *filename=[asset valueForKey:@"filename"];
        NSString *fullpath=[NSString stringWithFormat:@"%@/%@%@", dmcPickerPath,[[NSProcessInfo processInfo] globallyUniqueString], filename];
            
        //增加 判断如果heic图片 转换一次
        __block BOOL isHEIF = NO;
        if (iOSVersionGreaterThanOrEqualTo(@"9.0")) {
            NSArray *resourceList = [PHAssetResource assetResourcesForAsset:asset];
            [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 = [asset valueForKey:@"uniformTypeIdentifier"];
            isHEIF = [UTI isEqualToString:@"public.heif"] || [UTI isEqualToString:@"public.heic"];
        }
            
            
        if (isHEIF) {
            CIImage *ciImage = [CIImage imageWithData:imageData];
            CIContext *context = [CIContext context];
            imageData = [context JPEGRepresentationOfImage:ciImage colorSpace:ciImage.colorSpace options:@{}];
        }
        //增加 判断如果heic图片 转换一次  end
    
        //对图片进行压缩
        UIImage *photo = [UIImage imageWithData: imageData];
        NSData *data;
        if ((limit_width > 0 || limit_height > 0) && limit_quality > 0) {
            float q = (float)limit_quality/100;
                
            CGFloat imgWidth = photo.size.width;
            CGFloat imgHeight = photo.size.height;
                
            //limit_width设置为0 不限宽 最大宽度为图片原宽
            int max_width=limit_width==0?imgWidth:limit_width;
            //limit_height设置为0 不限高 最大高度为图片原高
            int max_height=limit_height==0?imgHeight:limit_height;
                
            data = [UIImage compressScale:photo maxWidth:max_width maxHeight:max_height quality:q];
        } else {
            data = [UIImage lubanCompressImage:photo];
        }
        
        NSString *dmcPickerPath = [NSTemporaryDirectory() stringByAppendingPathComponent:@"dmcPicker"];
        NSFileManager *fileManager = [NSFileManager defaultManager];
        if(![fileManager fileExistsAtPath:dmcPickerPath ]){
            [fileManager createDirectoryAtPath:dmcPickerPath withIntermediateDirectories:YES attributes:nil error:nil];
        }
        filename = [NSString stringWithFormat:@"%@%@%@",@"dmcMediaPickerCompress", [self currentTimeStr],@".jpg"];
        fullpath = [NSString stringWithFormat:@"%@/%@", dmcPickerPath,filename];
        NSNumber* size = [NSNumber numberWithLong: data.length];
            
        NSError *error = nil;
        if (![data writeToFile:fullpath options:NSAtomicWrite error:&error]) {
            NSLog(@"%@", [error localizedDescription]);
            [self.commandDelegate sendPluginResult:[CDVPluginResult resultWithStatus:CDVCommandStatus_ERROR messageAsString:[error localizedDescription]] callbackId:callbackId];
        } else {
            NSDictionary *dict=[NSDictionary dictionaryWithObjectsAndKeys:fullpath,@"path",[[NSURL fileURLWithPath:fullpath] absoluteString],@"uri",@"image",@"mediaType",size,@"size",[NSNumber numberWithInt:index],@"index", nil];
            [aListArray addObject:dict];
            if([aListArray count]==[selectArray count]){
                [self.commandDelegate sendPluginResult:[CDVPluginResult resultWithStatus:CDVCommandStatus_OK messageAsArray:aListArray] callbackId:callbackId];
            }
        }
    }];
    

    参考:https://www.jianshu.com/p/a63c7d5d98a9

    相关文章

      网友评论

          本文标题:iOS 图片选择 heic 格式图片转 jpg

          本文链接:https://www.haomeiwen.com/subject/vvxqwctx.html