Support more image formats on Android

Author: ueman

packages/google_mlkit_commons/android/src/main/java/com/google_mlkit_commons/InputImageConverter.java

@@ -37,7 +37,7 @@ public static InputImage getInputImageFromData(Map<String, Object> imageData,
                     (int) (double) metaData.get("width"),
                     (int) (double) metaData.get("height"),
                     (int) metaData.get("rotation"),
-                    InputImage.IMAGE_FORMAT_NV21);
+                    (int) imageData.get("image_format"));
             return inputImage;
         } else {
             result.error("InputImageConverterError", "Invalid Input Image", null);

packages/google_mlkit_commons/lib/src/input_image.dart

@@ -62,7 +62,11 @@ class InputImageMetadata {
 
   /// Format of the input image.
   ///
-  /// Not used on Android.
+  /// Android only supports
+  /// - [InputImageFormat.nv21]
+  /// - [InputImageFormat.yuv_420_888]
+  /// - [InputImageFormat.yv12]
+  /// as described in [here](https://developers.google.com/android/reference/com/google/mlkit/vision/common/InputImage.ImageFormat).
   final InputImageFormat format;
 
   /// The row stride for color plane, in bytes.