Added some options (max width/height and quality) to the takePicture …

…call.
RobertSasak · Jul 22, 2019 · fdffed4 · fdffed4
1 parent 97230d2
commit fdffed4
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Showing 2 changed files with 50 additions and 4 deletions.
diff --git a/index.js b/index.js
@@ -98,10 +98,11 @@ export default class Camera extends Component {
   }
 
   // Take a picture of what is currently seen by the user.
+  // Possible options: width (int), height (int) and quality (float).
   // @return a Promise<String:uri>.
   // @warn Currently only works on iOS.
-  async takePicture() {
-    return await CameraManager.takePicture();
+  async takePicture(options) {
+    return await CameraManager.takePicture(options);
   }
 
   render() {

diff --git a/ios/ALPRCameraManager.mm b/ios/ALPRCameraManager.mm
@@ -192,22 +192,67 @@ - (id)init {
     }];
 }
 
-RCT_EXPORT_METHOD(takePicture:(RCTPromiseResolveBlock)resolve
+RCT_EXPORT_METHOD(takePicture:(NSDictionary *)options
+                  resolve:(RCTPromiseResolveBlock)resolve
                   reject:(RCTPromiseRejectBlock)reject) {
     AVCaptureConnection *connection = [self.stillImageOutput connectionWithMediaType:AVMediaTypeVideo];
     [connection setVideoOrientation:self.previewLayer.connection.videoOrientation];
     [self.stillImageOutput captureStillImageAsynchronouslyFromConnection:connection completionHandler: ^(CMSampleBufferRef imageSampleBuffer, NSError *error) {
         if (imageSampleBuffer && !error) {
             NSData *imageData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageSampleBuffer];
+            NSData* compressedImage = [ALPRCameraManager imageWithImage:imageData options:options];
             NSString *path = [ALPRCameraManager generatePathInDirectory:[[ALPRCameraManager cacheDirectoryPath] stringByAppendingPathComponent:@"Camera"] withExtension:@".jpg"];
-            NSString *uri = [ALPRCameraManager writeImage:imageData toPath:path];
+            NSString *uri = [ALPRCameraManager writeImage:compressedImage toPath:path];
             resolve(uri);
         } else {
             reject(@"E_IMAGE_CAPTURE_FAILED", @"Image could not be captured", error);
         }
     }];
 }
 
++ (NSData *)imageWithImage:(NSData *)imageData options:(NSDictionary *)options {
+    UIImage *image = [UIImage imageWithData:imageData];
+
+    // Calculate the image size.
+    int width = 0, height = 0;
+    float quality;
+
+    if([options valueForKey:@"width"] != nil) {
+        width = [options[@"width"] intValue];
+    }
+    if([options valueForKey:@"height"] != nil) {
+        height = [options[@"height"] intValue];
+    }
+
+    if(image.size.width > image.size.height) {
+        if(width == 0) {
+            width = image.size.width; // Default max width
+        }
+        height = width * image.size.height / image.size.width;
+
+    } else {
+        if(height == 0) {
+            height = image.size.height; // Default max height
+        }
+        width = height * image.size.width / image.size.height;
+    }
+    CGSize size = CGSizeMake(width,height);
+
+    if([options valueForKey:@"quality"] != nil) {
+        quality = [options[@"quality"] floatValue];
+    } else {
+        quality = 1.0; // Default quality
+    }
+
+    UIGraphicsBeginImageContext(size);
+    [image drawInRect:CGRectMake(0, 0, size.width, size.height)];
+    UIImage *destImage = UIGraphicsGetImageFromCurrentImageContext();
+    UIGraphicsEndImageContext();
+
+    NSData *destData = UIImageJPEGRepresentation(destImage, quality);
+    return destData;
+}
+
 + (NSString *)generatePathInDirectory:(NSString *)directory withExtension:(NSString *)extension
 {
     NSString *fileName = [[[NSUUID UUID] UUIDString] stringByAppendingString:extension];