initial push to GitHub

.gitignore

@@ -0,0 +1,2 @@
+.DS_Store
+xcuserdata

README.md

@@ -0,0 +1,36 @@
+# Tensorflow iOS Object Detection
+
+An Object Detection application on iOS using Tensorflow and pre-trained COCO dataset models.  Video frames are captured and inference is done locally using one of the 3 provided models: ssd_mobilenet_v1_coco, ssd_inception_v2_coco, and faster_rcnn_resnet101_coco.  Both Swift and Objective-C projects.
+
+![cat image](images/cat.png)
+
+## Building
+
+* Make sure you have automake and libtool.  Using homebrew:
+
+`brew install automake libtool`
+
+
+* Clone the tensorflow source repo on GitHub
+
+`git clone https://github.com/tensorflow/tensorflow`
+
+
+* We need to build the tensorflow components with ANDROID_TYPES_FULL.  In the terminal type:
+
+`export ANDROID_TYPES="-D__ANDROID_TYPES_FULL__"`
+
+
+* Build the tensorflow libraries for iOS.  Go to the root of your newly downloaded tensorflow repo and run:
+
+`tensorflow/contrib/makefile/build_all_ios.sh`
+
+Go get a coffee. This can take a while.  On my macBook it took almost 2 hours.
+
+
+* Open either the Swift of Objective-C project in this repo and edit the **tensorflow.xconfig** file to point to the folder where you cloned the tensorflow repo
+
+`TENSORFLOW_ROOT=/Users/username/Development/tensorflow`
+
+
+* Compile the xcode project and run. Since we need a camera this will only run on a device.

objC/App/AppDelegate.h

@@ -0,0 +1,8 @@
+
+@import UIKit;
+
+@interface AppDelegate : UIResponder <UIApplicationDelegate>
+
+@property (nonatomic) UIWindow *window;
+
+@end

objC/App/AppDelegate.m

@@ -0,0 +1,5 @@
+
+#import "AppDelegate.h"
+
+@implementation AppDelegate
+@end

objC/App/BoundingBoxView.h

@@ -0,0 +1,17 @@
+//
+//  BoundingBoxView.h
+//  tensorflowiOS
+//
+//  Created by Sharp, Chris T on 10/9/17.
+//  Copyright © 2017 Apple. All rights reserved.
+//
+
+#import <UIKit/UIKit.h>
+
+@interface BoundingBoxView : UIView
+
+@property (nonatomic) NSMutableArray* labels;
+
+- (void) updateBoundingBoxes: (NSArray*) boxes;
+
+@end

objC/App/BoundingBoxView.m

@@ -0,0 +1,142 @@
+//
+//  BoundingBoxView.m
+//  tensorflowiOS
+//
+//  Created by Sharp, Chris T on 10/9/17.
+//  Copyright © 2017 Apple. All rights reserved.
+//
+
+#import "BoundingBoxView.h"
+#import "TensorflowPrediction.h"
+
+const CGFloat BoundingBoxLineWidth = 3.5f;
+
+@interface BoundingBoxView()
+@property (nonatomic) NSArray *boxesToBeErased;
+@property (nonatomic) NSArray *boxesToBeDrawn;
+@end
+
+@implementation BoundingBoxView
+
+- (instancetype)initWithCoder:(NSCoder *)coder
+{
+    self = [super initWithCoder:coder];
+    if (self)
+    {
+        //
+        // Maintain a list of UILabels for easy removal from superView.
+        //
+        self.labels = [[NSMutableArray alloc] init];
+    }
+    return self;
+}
+
+
+//
+// in drawRect we have a clear UIView that we draw green bounding boxes on.
+// As a new list of boundingboxes comes in we erase the old boxes and draw the new ones.
+// Since this view is just a layer over the videoPreview the bounding boxes could be a few
+// frames behind and the box will not align with the object underneath it.  This will likely
+// be an issue until Tensorflow processing is as fast as the video preview's frame capture.
+//
+- (void)drawRect:(CGRect)rect
+{
+    //
+    // Our drawing context
+    //
+    CGContextRef context = UIGraphicsGetCurrentContext();
+
+    //
+    // The width of the bounding box lines.
+    //
+    CGContextSetLineWidth(context, BoundingBoxLineWidth);
+
+    //
+    // The fill color of the bounding box is always clear
+    //
+    CGContextSetRGBFillColor(context, 1.0, 1.0, 1.0, 0.0);
+
+    //
+    // Erase boxes from the previous frame
+    //
+    if (self.boxesToBeErased)
+    {
+        for (TensorflowPrediction* pred in self.boxesToBeErased)
+        {
+            // Erase the previous bounding box by using a clear stroke color
+            CGContextSetRGBStrokeColor(context, 1.0, 1.0, 1.0, 0.0);
+
+            // Calculate box dimensions of box to be erased.
+            CGFloat x = pred.left    * self.frame.size.width;
+            CGFloat y = pred.top     * self.frame.size.height;
+            CGFloat w = (pred.right  * self.frame.size.width)  - x;
+            CGFloat h = (pred.bottom * self.frame.size.height) - y;
+            CGRect rectangle = CGRectMake(x, y, w, h);
+
+            //Erase it. (draw clear pixels over the green)
+            CGContextFillRect(context, rectangle);
+            CGContextStrokeRect(context, rectangle);
+        }
+
+        //
+        // Remove existing labels too.
+        //
+        for (UILabel * label in self.labels)
+        {
+            [label removeFromSuperview];
+        }
+        [self.labels removeAllObjects];
+        self.boxesToBeErased = nil;
+    }
+
+    //
+    // Draw newly predicted boxes
+    //
+    for (TensorflowPrediction* pred in self.boxesToBeDrawn)
+    {
+        //
+        // Calculate the box dimensions.  The box dimensions are given
+        // as normalized values. Because this view has the same dimensions
+        // as the original image multiplying by width and height gives the
+        // correct location for the bounding box.
+        //
+        CGFloat x = pred.left    * self.frame.size.width;
+        CGFloat y = pred.top     * self.frame.size.height;
+        CGFloat w = (pred.right  * self.frame.size.width)  - x;
+        CGFloat h = (pred.bottom * self.frame.size.height) - y;
+        CGRect rectangle = CGRectMake(x, y, w, h);
+
+        // Draw with a green stroke.
+        CGContextSetRGBStrokeColor(context, 0.0, 1.0, 0.0, 0.75);
+        CGContextFillRect(context, rectangle);
+        CGContextStrokeRect(context, rectangle);
+
+        // Add the label to the upper left of the bounding box
+        UILabel * label = [[UILabel alloc] initWithFrame:CGRectMake(x, y, 75, 35)];
+        [label setBackgroundColor:[UIColor whiteColor]];
+        [label setTextColor:[UIColor orangeColor]];
+        [label setText:pred.label];
+        [self addSubview:label];
+
+        //
+        // Keep a list of labels so we can easily remove from superview.
+        //
+        [self.labels addObject:label];
+    }
+}
+
+- (void) updateBoundingBoxes: (NSArray*) boxes
+{
+    //
+    // flag the old boxes to be erased and flag the new to be drawn.
+    //
+    self.boxesToBeErased = self.boxesToBeDrawn;
+    self.boxesToBeDrawn = boxes;
+
+    //
+    // trigger a drawRect call next frame
+    //
+    [self setNeedsDisplay];
+}
+
+@end

objC/App/CameraPreviewView.h

@@ -0,0 +1,12 @@
+
+#import <UIKit/UIKit.h>
+
+@class AVCaptureSession;
+
+@interface CameraPreviewView : UIView
+@property (nonatomic, readonly) AVCaptureVideoPreviewLayer *videoPreviewLayer;
+
+- (void) configureSession;
+- (void) startSessionWithDelegate: (id<AVCaptureVideoDataOutputSampleBufferDelegate>) delegate;
+- (void) stopSession;
+@end