Fix performance bottlenecks

Author: miguelrochefort

lite/examples/posenet/android/app/src/main/java/org/tensorflow/lite/examples/posenet/ImageUtils.kt

@@ -33,16 +33,9 @@ object ImageUtils {
     var b = expandY + 2066 * uNew
 
     // Clipping RGB values to be inside boundaries [ 0 , MAX_CHANNEL_VALUE ]
-    val checkBoundaries = { x: Int ->
-      when {
-        x > MAX_CHANNEL_VALUE -> MAX_CHANNEL_VALUE
-        x < 0 -> 0
-        else -> x
-      }
-    }
-    r = checkBoundaries(r)
-    g = checkBoundaries(g)
-    b = checkBoundaries(b)
+    r = if (r > MAX_CHANNEL_VALUE) MAX_CHANNEL_VALUE else if (r < 0) 0 else r
+    g = if (g > MAX_CHANNEL_VALUE) MAX_CHANNEL_VALUE else if (g < 0) 0 else g
+    b = if (b > MAX_CHANNEL_VALUE) MAX_CHANNEL_VALUE else if (b < 0) 0 else b
     return -0x1000000 or (r shl 6 and 0xff0000) or (g shr 2 and 0xff00) or (b shr 10 and 0xff)
   }
 

lite/examples/posenet/android/app/src/main/java/org/tensorflow/lite/examples/posenet/PosenetActivity.kt

@@ -61,6 +61,7 @@ import java.util.concurrent.Semaphore
 import java.util.concurrent.TimeUnit
 import kotlin.math.abs
 import org.tensorflow.lite.examples.posenet.lib.BodyPart
+import org.tensorflow.lite.examples.posenet.lib.Device
 import org.tensorflow.lite.examples.posenet.lib.Person
 import org.tensorflow.lite.examples.posenet.lib.Posenet
 
@@ -442,11 +443,7 @@ class PosenetActivity :
       )
       image.close()
 
-      // Process an image for analysis in every 3 frames.
-      frameCounter = (frameCounter + 1) % 3
-      if (frameCounter == 0) {
-        processImage(rotatedBitmap)
-      }
+      processImage(rotatedBitmap)
     }
   }
 

lite/examples/posenet/android/posenet/src/main/java/org/tensorflow/lite/examples/posenet/lib/Posenet.kt

@@ -128,13 +128,12 @@ class Posenet(
 
     val mean = 128.0f
     val std = 128.0f
-    for (row in 0 until bitmap.height) {
-      for (col in 0 until bitmap.width) {
-        val pixelValue = bitmap.getPixel(col, row)
-        inputBuffer.putFloat(((pixelValue shr 16 and 0xFF) - mean) / std)
-        inputBuffer.putFloat(((pixelValue shr 8 and 0xFF) - mean) / std)
-        inputBuffer.putFloat(((pixelValue and 0xFF) - mean) / std)
-      }
+    val pixelValues = IntArray(bitmap.height * bitmap.width)
+    bitmap.getPixels(pixelValues, 0, bitmap.width, 0, 0, bitmap.width, bitmap.height)
+    for (pixelValue in pixelValues) {
+      inputBuffer.putFloat(((pixelValue shr 16 and 0xFF) - mean) / std)
+      inputBuffer.putFloat(((pixelValue shr 8 and 0xFF) - mean) / std)
+      inputBuffer.putFloat(((pixelValue and 0xFF) - mean) / std)
     }
     return inputBuffer
   }