Fixed all memory leaks in segmentation view

apps/segment/segment.js

@@ -457,8 +457,7 @@ function camicStopDraw(e) {
       } else {
         segmentModel(args.status);
       }
-      var memory = tf.memory();
-      console.log(memory);
+      console.log(tf.memory());
       $UI.segmentPanel.setPosition(box.rect.x,box.rect.y,box.rect.width,box.rect.height);
       $UI.segmentPanel.open(args);
 
@@ -686,7 +685,11 @@ async function segmentModel(key) {
 
     model = await tf.loadLayersModel(IDB_URL + key);
     console.log('Model Loaded');
-
+    const memory = tf.memory()
+    console.log("Model Memory Usage")
+    console.log("GPU : " + memory.numBytesInGPU + " bytes")
+    console.log("Total : " + memory.numBytes + " bytes")
+
     tf.tidy(()=>{
     // Warmup the model before using real data.
     const warmupResult = model.predict(tf.zeros([1, image_size, image_size, input_channels]));
@@ -735,6 +738,7 @@ async function segmentModel(key) {
         } else {
           img2 = tf.image.resizeBilinear(img, [image_size, image_size]);
         }
+        img.dispose()
         let scaleMethod = $UI.filter? $UI.filter.status: 'norm';
         console.log(scaleMethod);
 
@@ -761,7 +765,7 @@ async function segmentModel(key) {
           let std = (img2.squaredDifference(mean).sum()).div(img2.flatten().shape).sqrt();
           normalized = img2.sub(mean).div(std);
         }      
-
+        img2.dispose()
 
         let batched = normalized.reshape([1, image_size, image_size, input_channels]);
         let values = model.predict(batched).dataSync();
@@ -771,9 +775,10 @@ async function segmentModel(key) {
         val = new Array();
         while (values.length > 0) val.push(values.splice(0, image_size));
         });
+        tf.engine().startScope()
         await tf.browser.toPixels(val, temp);
-        finalRes.getContext('2d').drawImage(temp, dx, dy);    
-
+        finalRes.getContext('2d').drawImage(temp, dx, dy);  
+        tf.engine().endScope()
         dx += step;
       }
       dy += step;