Recognize text from image using firebase_ml_vision and Cloud Vision API

ios/Podfile

@@ -1,5 +1,4 @@
-# Uncomment this line to define a global platform for your project
-# platform :ios, '9.0'
+platform :ios, '9.0'
 
 # CocoaPods analytics sends network stats synchronously affecting flutter build latency.
 ENV['COCOAPODS_DISABLE_STATS'] = 'true'

ios/Podfile.lock

@@ -6,12 +6,19 @@ PODS:
     - FirebaseAnalytics (= 6.2.2)
   - Firebase/CoreOnly (6.17.0):
     - FirebaseCore (= 6.6.2)
+  - Firebase/MLVision (6.17.0):
+    - Firebase/CoreOnly
+    - FirebaseMLVision (~> 0.19.0)
   - firebase_analytics (0.0.1):
     - Firebase/Core
     - Flutter
   - firebase_core (0.0.1):
     - Firebase/Core
     - Flutter
+  - firebase_ml_vision (0.1.1):
+    - Firebase/Core
+    - Firebase/MLVision
+    - Flutter
   - FirebaseAnalytics (6.2.2):
     - FirebaseCore (~> 6.6)
     - FirebaseInstanceID (~> 4.3)
@@ -42,7 +49,30 @@ PODS:
     - FirebaseInstallations (~> 1.0)
     - GoogleUtilities/Environment (~> 6.5)
     - GoogleUtilities/UserDefaults (~> 6.5)
+  - FirebaseMLCommon (0.19.0):
+    - FirebaseCore (~> 6.3)
+    - FirebaseInstanceID (~> 4.2)
+    - GoogleToolboxForMac/Logger (~> 2.1)
+    - "GoogleToolboxForMac/NSData+zlib (~> 2.1)"
+    - "GoogleToolboxForMac/NSDictionary+URLArguments (~> 2.1)"
+    - GoogleUtilities/UserDefaults (~> 6.0)
+    - GTMSessionFetcher/Core (~> 1.1)
+    - Protobuf (~> 3.5)
+  - FirebaseMLVision (0.19.0):
+    - FirebaseCore (~> 6.3)
+    - FirebaseMLCommon (~> 0.19)
+    - GoogleAPIClientForREST/Core (~> 1.3)
+    - GoogleAPIClientForREST/Vision (~> 1.3)
+    - GoogleToolboxForMac/Logger (~> 2.1)
+    - "GoogleToolboxForMac/NSData+zlib (~> 2.1)"
+    - GTMSessionFetcher/Core (~> 1.1)
+    - Protobuf (~> 3.5)
   - Flutter (1.0.0)
+  - GoogleAPIClientForREST/Core (1.3.11):
+    - GTMSessionFetcher (>= 1.1.7)
+  - GoogleAPIClientForREST/Vision (1.3.11):
+    - GoogleAPIClientForREST/Core
+    - GTMSessionFetcher (>= 1.1.7)
   - GoogleAppMeasurement (6.2.2):
     - GoogleUtilities/AppDelegateSwizzler (~> 6.0)
     - GoogleUtilities/MethodSwizzler (~> 6.0)
@@ -53,6 +83,18 @@ PODS:
   - GoogleDataTransportCCTSupport (1.4.0):
     - GoogleDataTransport (~> 4.0)
     - nanopb (~> 0.3.901)
+  - GoogleToolboxForMac/DebugUtils (2.2.2):
+    - GoogleToolboxForMac/Defines (= 2.2.2)
+  - GoogleToolboxForMac/Defines (2.2.2)
+  - GoogleToolboxForMac/Logger (2.2.2):
+    - GoogleToolboxForMac/Defines (= 2.2.2)
+  - "GoogleToolboxForMac/NSData+zlib (2.2.2)":
+    - GoogleToolboxForMac/Defines (= 2.2.2)
+  - "GoogleToolboxForMac/NSDictionary+URLArguments (2.2.2)":
+    - GoogleToolboxForMac/DebugUtils (= 2.2.2)
+    - GoogleToolboxForMac/Defines (= 2.2.2)
+    - "GoogleToolboxForMac/NSString+URLArguments (= 2.2.2)"
+  - "GoogleToolboxForMac/NSString+URLArguments (2.2.2)"
   - GoogleUtilities/AppDelegateSwizzler (6.5.1):
     - GoogleUtilities/Environment
     - GoogleUtilities/Logger
@@ -71,6 +113,11 @@ PODS:
     - GoogleUtilities/Logger
   - GoogleUtilities/UserDefaults (6.5.1):
     - GoogleUtilities/Logger
+  - GTMSessionFetcher (1.3.1):
+    - GTMSessionFetcher/Full (= 1.3.1)
+  - GTMSessionFetcher/Core (1.3.1)
+  - GTMSessionFetcher/Full (1.3.1):
+    - GTMSessionFetcher/Core (= 1.3.1)
   - nanopb (0.3.9011):
     - nanopb/decode (= 0.3.9011)
     - nanopb/encode (= 0.3.9011)
@@ -79,11 +126,13 @@ PODS:
   - path_provider (0.0.1):
     - Flutter
   - PromisesObjC (1.2.8)
+  - Protobuf (3.11.4)
 
 DEPENDENCIES:
   - camera (from `.symlinks/plugins/camera/ios`)
   - firebase_analytics (from `.symlinks/plugins/firebase_analytics/ios`)
   - firebase_core (from `.symlinks/plugins/firebase_core/ios`)
+  - firebase_ml_vision (from `.symlinks/plugins/firebase_ml_vision/ios`)
   - Flutter (from `Flutter`)
   - path_provider (from `.symlinks/plugins/path_provider/ios`)
 
@@ -96,12 +145,18 @@ SPEC REPOS:
     - FirebaseCoreDiagnosticsInterop
     - FirebaseInstallations
     - FirebaseInstanceID
+    - FirebaseMLCommon
+    - FirebaseMLVision
+    - GoogleAPIClientForREST
     - GoogleAppMeasurement
     - GoogleDataTransport
     - GoogleDataTransportCCTSupport
+    - GoogleToolboxForMac
     - GoogleUtilities
+    - GTMSessionFetcher
     - nanopb
     - PromisesObjC
+    - Protobuf
 
 EXTERNAL SOURCES:
   camera:
@@ -110,6 +165,8 @@ EXTERNAL SOURCES:
     :path: ".symlinks/plugins/firebase_analytics/ios"
   firebase_core:
     :path: ".symlinks/plugins/firebase_core/ios"
+  firebase_ml_vision:
+    :path: ".symlinks/plugins/firebase_ml_vision/ios"
   Flutter:
     :path: Flutter
   path_provider:
@@ -120,21 +177,28 @@ SPEC CHECKSUMS:
   Firebase: 2672e5636b42f977177716317e68346ae5e9de25
   firebase_analytics: bd50d8f5d3f42dcab6da67944a849062470b0a19
   firebase_core: ce5006bb48508ee4e71e0f429a3f519bb8ee2961
+  firebase_ml_vision: a40524ef47717f380239e19567c9dc050d8cc1de
   FirebaseAnalytics: cf95d3aab897612783020fbd98401d5366f135ee
   FirebaseCore: a1dd9dd6355a8356dd30a8f076839e242285a81c
   FirebaseCoreDiagnostics: 5e78803ab276bc5b50340e3c539c06c3de35c649
   FirebaseCoreDiagnosticsInterop: 296e2c5f5314500a850ad0b83e9e7c10b011a850
   FirebaseInstallations: 575cd32f2aec0feeb0e44f5d0110a09e5e60b47b
   FirebaseInstanceID: 031d7d0c8e7b5c030bbeb4d2a690550375e83fec
+  FirebaseMLCommon: 074a67e05122b1c9f6401a4e33b2cea3b4efd224
+  FirebaseMLVision: 7a456009787690e3b53436092ae9b635563de8f3
   Flutter: 0e3d915762c693b495b44d77113d4970485de6ec
+  GoogleAPIClientForREST: 0f19a8280dfe6471f76016645d26eb5dae305101
   GoogleAppMeasurement: d0560d915abf15e692e8538ba1d58442217b6aff
   GoogleDataTransport: 47fe3b8e1673e5187dfd615656a3c5034f150d69
   GoogleDataTransportCCTSupport: 36f69887fd212db6d7ef4dd45ba44523717a434e
+  GoogleToolboxForMac: 800648f8b3127618c1b59c7f97684427630c5ea3
   GoogleUtilities: 06eb53bb579efe7099152735900dd04bf09e7275
+  GTMSessionFetcher: cea130bbfe5a7edc8d06d3f0d17288c32ffe9925
   nanopb: 18003b5e52dab79db540fe93fe9579f399bd1ccd
   path_provider: fb74bd0465e96b594bb3b5088ee4a4e7bb1f2a9d
   PromisesObjC: c119f3cd559f50b7ae681fa59dc1acd19173b7e6
+  Protobuf: 176220c526ad8bd09ab1fb40a978eac3fef665f7
 
-PODFILE CHECKSUM: 1b66dae606f75376c5f2135a8290850eeb09ae83
+PODFILE CHECKSUM: 836bcbcff58bec3d0a1a7a17cf269f9fcc45b6cb
 
 COCOAPODS: 1.8.4

lib/widgets/screens/camera.dart

@@ -2,6 +2,7 @@ import 'dart:async';
 import 'dart:io';
 
 import 'package:camera/camera.dart';
+import 'package:firebase_ml_vision/firebase_ml_vision.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_sandbox/widgets/components/drawer.dart';
 import 'package:path/path.dart' show join;
@@ -89,11 +90,21 @@ class TakePictureScreenState extends State<TakePictureScreen> {
             // Attempt to take a picture and log where it's been saved.
             await _controller.takePicture(path);
 
+            // Recognize text from image using Cloud Vision API
+            final File imageFile = File(path);
+            final FirebaseVisionImage visionImage =
+                FirebaseVisionImage.fromFile(imageFile);
+            final TextRecognizer textRecognizer =
+                FirebaseVision.instance.cloudTextRecognizer();
+            final VisionText visionText =
+                await textRecognizer.processImage(visionImage);
+
             // If the picture was taken, display it on a new screen.
             Navigator.push(
               context,
               MaterialPageRoute(
-                builder: (context) => DisplayPictureScreen(imagePath: path),
+                builder: (context) => DisplayPictureScreen(
+                    imagePath: path, recognizedText: visionText.text),
               ),
             );
           } catch (e) {
@@ -109,16 +120,27 @@ class TakePictureScreenState extends State<TakePictureScreen> {
 // A widget that displays the picture taken by the user.
 class DisplayPictureScreen extends StatelessWidget {
   final String imagePath;
+  final String recognizedText;
 
-  const DisplayPictureScreen({Key key, this.imagePath}) : super(key: key);
+  const DisplayPictureScreen({Key key, this.imagePath, this.recognizedText})
+      : super(key: key);
 
   @override
   Widget build(BuildContext context) {
     return Scaffold(
       appBar: AppBar(title: Text('Display the Picture')),
       // The image is stored as a file on the device. Use the `Image.file`
       // constructor with the given path to display the image.
-      body: Image.file(File(imagePath)),
+      body: Center(
+        child: SingleChildScrollView(
+          child: Column(
+            children: <Widget>[
+              Image.file(File(imagePath)),
+              Text(recognizedText),
+            ],
+          ),
+        ),
+      ),
     );
   }
 }

pubspec.lock

@@ -85,6 +85,13 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "0.2.5+1"
+  firebase_ml_vision:
+    dependency: "direct main"
+    description:
+      name: firebase_ml_vision
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.9.3+5"
   flutter:
     dependency: "direct main"
     description: flutter

pubspec.yaml

@@ -11,6 +11,7 @@ dependencies:
   cupertino_icons: ^0.1.2
   firebase_core: ^0.2.5
   firebase_analytics: ^1.0.4
+  firebase_ml_vision: ^0.9.3+5
   flutter:
     sdk: flutter
   path: ^1.6.4