Change highlight alpha from filter to global alpha

Signed-off-by: Justin Georgi <justin.georgi@gmail.com>

src/pages/detect.vue

@@ -501,9 +501,9 @@
           this.imCvsLocation.left = imageLoc[0].cvsLeft
           this.imCvsLocation.width = imageLoc[0].cvsRight - imageLoc[0].cvsLeft
           this.imCvsLocation.height = imageLoc[0].cvsBottom - imageLoc[0].cvsTop
-          if (drawChip) {imageCtx.filter = "grayscale(1) opacity(.5)"}
+          if (drawChip) {imageCtx.globalAlpha = .5}
           imageCtx.drawImage(this.imageView, 0, 0, this.imageView.width, this.imageView.height, this.imCvsLocation.left, this.imCvsLocation.top, this.imCvsLocation.width, this.imCvsLocation.height)
-          if (drawChip) {imageCtx.filter = "grayscale(0) opacity(1)"}
+          if (drawChip) {imageCtx.globalAlpha = 1}
         }
         this.structureZoomed = false
         return [imCanvas, imageCtx]