Add an option to postprocess masks during inference (#180)

* Add an option to postprocess masks during inference

* Fix COCO evaluation to resize masks ony if needed.

* Fix casting

* Fix minor issues in paste_mask_in_image

* Cast mask to uint8

* Make Masker batch compatible

* Remove warnings and stylistic changes

maskrcnn_benchmark/config/defaults.py

@@ -194,6 +194,9 @@
 _C.MODEL.ROI_MASK_HEAD.CONV_LAYERS = (256, 256, 256, 256)
 _C.MODEL.ROI_MASK_HEAD.RESOLUTION = 14
 _C.MODEL.ROI_MASK_HEAD.SHARE_BOX_FEATURE_EXTRACTOR = True
+# Whether or not resize and translate masks to the input image.
+_C.MODEL.ROI_MASK_HEAD.POSTPROCESS_MASKS = False
+_C.MODEL.ROI_MASK_HEAD.POSTPROCESS_MASKS_THRESHOLD = 0.5
 
 # ---------------------------------------------------------------------------- #
 # ResNe[X]t options (ResNets = {ResNet, ResNeXt}

maskrcnn_benchmark/engine/inference.py

@@ -87,8 +87,12 @@ def prepare_for_coco_segmentation(predictions, dataset):
         image_height = dataset.coco.imgs[original_id]["height"]
         prediction = prediction.resize((image_width, image_height))
         masks = prediction.get_field("mask")
+
         # t = time.time()
-        masks = masker(masks, prediction)
+        # Masker is necessary only if masks haven't been already resized.
+        if list(masks.shape[-2:]) != [image_height, image_width]:
+            masks = masker(masks.expand(1, -1, -1, -1, -1), prediction)
+            masks = masks[0]
         # logger.info('Time mask: {}'.format(time.time() - t))
         # prediction = prediction.convert('xywh')
 
@@ -426,6 +430,6 @@ def inference(
     check_expected_results(results, expected_results, expected_results_sigma_tol)
     if output_folder:
         torch.save(results, os.path.join(output_folder, "coco_results.pth"))
-        
+
     return results, coco_results, predictions
 

maskrcnn_benchmark/modeling/roi_heads/mask_head/inference.py

@@ -1,8 +1,8 @@
 # Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
 import numpy as np
 import torch
-from PIL import Image
 from torch import nn
+import torch.nn.functional as F
 
 from maskrcnn_benchmark.structures.bounding_box import BoxList
 
@@ -44,12 +44,12 @@ def forward(self, x, boxes):
         index = torch.arange(num_masks, device=labels.device)
         mask_prob = mask_prob[index, labels][:, None]
 
-        if self.masker:
-            mask_prob = self.masker(mask_prob, boxes)
-
         boxes_per_image = [len(box) for box in boxes]
         mask_prob = mask_prob.split(boxes_per_image, dim=0)
 
+        if self.masker:
+            mask_prob = self.masker(mask_prob, boxes)
+
         results = []
         for prob, box in zip(mask_prob, boxes):
             bbox = BoxList(box.bbox, box.size, mode="xyxy")
@@ -119,25 +119,28 @@ def paste_mask_in_image(mask, box, im_h, im_w, thresh=0.5, padding=1):
     padded_mask, scale = expand_masks(mask[None], padding=padding)
     mask = padded_mask[0, 0]
     box = expand_boxes(box[None], scale)[0]
-    box = box.numpy().astype(np.int32)
+    box = box.to(dtype=torch.int32)
 
     TO_REMOVE = 1
     w = box[2] - box[0] + TO_REMOVE
     h = box[3] - box[1] + TO_REMOVE
     w = max(w, 1)
     h = max(h, 1)
 
-    mask = Image.fromarray(mask.cpu().numpy())
-    mask = mask.resize((w, h), resample=Image.BILINEAR)
-    mask = np.array(mask, copy=False)
+    # Set shape to [batchxCxHxW]
+    mask = mask.expand((1, 1, -1, -1))
+
+    # Resize mask
+    mask = mask.to(torch.float32)
+    mask = F.interpolate(mask, size=(h, w), mode='bilinear', align_corners=False)
+    mask = mask[0][0]
 
     if thresh >= 0:
-        mask = np.array(mask > thresh, dtype=np.uint8)
-        mask = torch.from_numpy(mask)
+        mask = mask > thresh
     else:
         # for visualization and debugging, we also
         # allow it to return an unmodified mask
-        mask = torch.from_numpy(mask * 255).to(torch.uint8)
+        mask = (mask * 255).to(torch.uint8)
 
     im_mask = torch.zeros((im_h, im_w), dtype=torch.uint8)
     x_0 = max(box[0], 0)
@@ -175,15 +178,27 @@ def forward_single_image(self, masks, boxes):
         return res
 
     def __call__(self, masks, boxes):
-        # TODO do this properly
         if isinstance(boxes, BoxList):
             boxes = [boxes]
-        assert len(boxes) == 1, "Only single image batch supported"
-        result = self.forward_single_image(masks, boxes[0])
-        return result
+
+        # Make some sanity check
+        assert len(boxes) == len(masks), "Masks and boxes should have the same length."
+
+        # TODO:  Is this JIT compatible?
+        # If not we should make it compatible.
+        results = []
+        for mask, box in zip(masks, boxes):
+            assert mask.shape[0] == len(box), "Number of objects should be the same."
+            result = self.forward_single_image(mask, box)
+            results.append(result)
+        return results
 
 
 def make_roi_mask_post_processor(cfg):
-    masker = None
+    if cfg.MODEL.ROI_MASK_HEAD.POSTPROCESS_MASKS:
+        mask_threshold = cfg.MODEL.ROI_MASK_HEAD.POSTPROCESS_MASKS_THRESHOLD
+        masker = Masker(threshold=mask_threshold, padding=1)
+    else:
+        masker = None
     mask_post_processor = MaskPostProcessor(masker)
     return mask_post_processor