示例#1
0
    def _sample_output(self, all_rois, gt_boxes, im_scale, gt_masks, mask_info,
                       init_state0):
        overlaps = bbox_overlaps(
            np.ascontiguousarray(all_rois[:, 1:5], dtype=np.float),
            np.ascontiguousarray(gt_boxes[:, :4], dtype=np.float))
        gt_assignment = overlaps.argmax(axis=1)
        max_overlaps = overlaps.max(axis=1)
        labels = gt_boxes[gt_assignment, 4]
        # Sample foreground indexes
        fg_inds = np.where(max_overlaps >= cfg.TRAIN.BBOX_THRESH)[0]
        bg_inds = np.where(max_overlaps < cfg.TRAIN.BBOX_THRESH)[0]
        keep_inds = np.append(fg_inds, bg_inds).astype(int)
        # Select sampled values from various arrays:
        labels = labels[keep_inds]
        # Clamp labels for the background RoIs to 0
        labels[len(fg_inds):] = 0
        rois = all_rois[keep_inds]
        #init_states = init_state0[keep_inds]
        init_states = init_state0

        bbox_target_data = bbox_compute_targets(
            rois[:, 1:5],
            gt_boxes[gt_assignment[keep_inds], :4],
            normalize=True)
        bbox_target_data = np.hstack((labels[:, np.newaxis], bbox_target_data))\
            .astype(np.float32, copy=False)
        bbox_targets, bbox_inside_weights = get_bbox_regression_label(
            bbox_target_data, 21)

        scaled_rois = rois[:, 1:5] / float(im_scale)
        scaled_gt_boxes = gt_boxes[:, :4] / float(im_scale)

        pos_masks = np.zeros((len(keep_inds), 1, cfg.MASK_SIZE, cfg.MASK_SIZE))
        top_mask_info = np.zeros((len(keep_inds), 12))
        top_mask_info[len(fg_inds):, :] = -1

        for i, val in enumerate(fg_inds):
            gt_box = scaled_gt_boxes[gt_assignment[val]]
            gt_box = np.around(gt_box).astype(int)
            ex_box = np.around(scaled_rois[i]).astype(int)
            gt_mask = gt_masks[gt_assignment[val]]
            gt_mask_info = mask_info[gt_assignment[val]]
            gt_mask = gt_mask[0:gt_mask_info[0], 0:gt_mask_info[1]]
            # regression targets is the intersection of bounding box and gt mask
            ex_mask = intersect_mask(ex_box, gt_box, gt_mask)
            pos_masks[i, ...] = ex_mask
            top_mask_info[i, 0] = gt_assignment[val]
            top_mask_info[i, 1] = gt_mask_info[0]
            top_mask_info[i, 2] = gt_mask_info[1]
            top_mask_info[i, 3] = labels[i]
            top_mask_info[i, 4:8] = ex_box
            top_mask_info[i, 8:12] = gt_box

        return labels, rois, fg_inds, keep_inds, pos_masks, top_mask_info, bbox_targets, bbox_inside_weights, init_states
示例#2
0
    def _sample_output(self, all_rois, gt_boxes, im_scale, gt_masks, mask_info):
        overlaps = bbox_overlaps(
            np.ascontiguousarray(all_rois[:, 1:5], dtype=np.float),
            np.ascontiguousarray(gt_boxes[:, :4], dtype=np.float))
        gt_assignment = overlaps.argmax(axis=1)
        max_overlaps = overlaps.max(axis=1)
        labels = gt_boxes[gt_assignment, 4]
        # Sample foreground indexes
        fg_inds = np.where(max_overlaps >= cfg.TRAIN.BBOX_THRESH)[0]
        bg_inds = np.where(max_overlaps < cfg.TRAIN.BBOX_THRESH)[0]
        keep_inds = np.append(fg_inds, bg_inds).astype(int)
        # Select sampled values from various arrays:
        labels = labels[keep_inds]
        # Clamp labels for the background RoIs to 0
        labels[len(fg_inds):] = 0
        rois = all_rois[keep_inds]

        bbox_target_data = bbox_compute_targets(
            rois[:, 1:5], gt_boxes[gt_assignment[keep_inds], :4], normalize=True)
        bbox_target_data = np.hstack((labels[:, np.newaxis], bbox_target_data))\
            .astype(np.float32, copy=False)
        bbox_targets, bbox_inside_weights = get_bbox_regression_label(
            bbox_target_data, 21)

        scaled_rois = rois[:, 1:5] / float(im_scale)
        scaled_gt_boxes = gt_boxes[:, :4] / float(im_scale)

        pos_masks = np.zeros((len(keep_inds), 1,  cfg.MASK_SIZE,  cfg.MASK_SIZE))
        top_mask_info = np.zeros((len(keep_inds), 12))
        top_mask_info[len(fg_inds):, :] = -1

        for i, val in enumerate(fg_inds):
            gt_box = scaled_gt_boxes[gt_assignment[val]]
            gt_box = np.around(gt_box).astype(int)
            ex_box = np.around(scaled_rois[i]).astype(int)
            gt_mask = gt_masks[gt_assignment[val]]
            gt_mask_info = mask_info[gt_assignment[val]]
            gt_mask = gt_mask[0:gt_mask_info[0], 0:gt_mask_info[1]]
            # regression targets is the intersection of bounding box and gt mask
            ex_mask = intersect_mask(ex_box, gt_box, gt_mask)
            pos_masks[i, ...] = ex_mask
            top_mask_info[i, 0] = gt_assignment[val]
            top_mask_info[i, 1] = gt_mask_info[0]
            top_mask_info[i, 2] = gt_mask_info[1]
            top_mask_info[i, 3] = labels[i]
            top_mask_info[i, 4:8] = ex_box
            top_mask_info[i, 8:12] = gt_box

        return labels, rois, fg_inds, keep_inds, pos_masks, top_mask_info, bbox_targets, bbox_inside_weights
示例#3
0
def _sample_rois(all_rois, gt_boxes, rois_per_image, num_classes, gt_masks, im_scale, mask_info):
    """
    Generate a random sample of RoIs comprising
    foreground and background examples.
    """
    # overlaps: (rois x gt_boxes)
    overlaps = bbox_overlaps(
        np.ascontiguousarray(all_rois[:, 1:5], dtype=np.float),
        np.ascontiguousarray(gt_boxes[:, :4], dtype=np.float))
    gt_assignment = overlaps.argmax(axis=1)
    max_overlaps = overlaps.max(axis=1)
    labels = gt_boxes[gt_assignment, 4]

    # Sample foreground indexes
    fg_inds = []
    for i in xrange(len(cfg.TRAIN.FG_FRACTION)):
        cur_inds = np.where((max_overlaps >= cfg.TRAIN.FG_THRESH_LO[i]) &
                            (max_overlaps <= cfg.TRAIN.FG_THRESH_HI[i]))[0]
        cur_rois_this_image = min(cur_inds.size, np.round(rois_per_image *
                                                          cfg.TRAIN.FG_FRACTION[i]))
        if cur_inds.size > 0:
            cur_inds = npr.choice(cur_inds, size=cur_rois_this_image, replace=False)
        fg_inds = np.hstack((fg_inds, cur_inds))
        fg_inds = np.unique(fg_inds)
    fg_rois_per_image = fg_inds.size
    # Sample background indexes according to number of foreground
    bg_rois_per_this_image = rois_per_image - fg_rois_per_image
    bg_inds = []
    for i in xrange(len(cfg.TRAIN.BG_FRACTION)):
        cur_inds = np.where((max_overlaps >= cfg.TRAIN.BG_THRESH_LO[i]) &
                            (max_overlaps <= cfg.TRAIN.BG_THRESH_HI[i]))[0]
        cur_rois_this_image = min(cur_inds.size, np.round(bg_rois_per_this_image *
                                                          cfg.TRAIN.BG_FRACTION[i]))
        if cur_inds.size > 0:
            cur_inds = npr.choice(cur_inds, size=cur_rois_this_image, replace=False)
        bg_inds = np.hstack((bg_inds, cur_inds))
        bg_inds = np.unique(bg_inds)

    # The indices that we're selecting (both fg and bg)
    keep_inds = np.append(fg_inds, bg_inds).astype(int)
    # Select sampled values from various arrays:
    labels = labels[keep_inds]
    # Clamp labels for the background RoIs to 0
    labels[fg_rois_per_image:] = 0
    rois = all_rois[keep_inds]

    bbox_target_data = bbox_compute_targets(
        rois[:, 1:5], gt_boxes[gt_assignment[keep_inds], :4], normalize=True)
    bbox_target_data = np.hstack((labels[:, np.newaxis], bbox_target_data))\
        .astype(np.float32, copy=False)
    bbox_targets, bbox_inside_weights = get_bbox_regression_label(
        bbox_target_data, num_classes)
    bbox_outside_weights = np.array(bbox_inside_weights > 0).astype(np.float32)

    blobs = {
        'rois': rois,
        'labels': labels,
        'bbox_targets': bbox_targets,
        'bbox_inside_weights': bbox_inside_weights,
        'bbox_outside_weights': bbox_outside_weights
    }

    if cfg.MNC_MODE:
        scaled_rois = rois[:, 1:5] / float(im_scale)

        # map to original image space
        scaled_gt_boxes = gt_boxes[:, :4] / float(im_scale)
        pos_masks = np.zeros((len(keep_inds), 1, cfg.MASK_SIZE,  cfg.MASK_SIZE))
        top_mask_info = np.zeros((len(keep_inds), 12))
        top_mask_info[len(fg_inds):, :] = -1

        for i, val in enumerate(fg_inds):
            gt_box = scaled_gt_boxes[gt_assignment[val]]
            gt_box = np.around(gt_box).astype(int)
            ex_box = np.around(scaled_rois[i]).astype(int)
            gt_mask = gt_masks[gt_assignment[val]]
            gt_mask_info = mask_info[gt_assignment[val]]
            gt_mask = gt_mask[0:gt_mask_info[0], 0:gt_mask_info[1]]
            # calculate mask regression targets
            # (intersection of bounding box and gt mask)
            ex_mask = intersect_mask(ex_box, gt_box, gt_mask)

            pos_masks[i, ...] = ex_mask
            top_mask_info[i, 0] = gt_assignment[val]
            top_mask_info[i, 1] = gt_mask_info[0]
            top_mask_info[i, 2] = gt_mask_info[1]
            top_mask_info[i, 3] = labels[i]

            top_mask_info[i, 4:8] = ex_box
            top_mask_info[i, 8:12] = gt_box

        mask_weight = np.zeros((rois.shape[0], 1, cfg.MASK_SIZE, cfg.MASK_SIZE))
        # only assign box-level foreground as positive mask regression
        mask_weight[0:len(fg_inds), :, :, :] = 1
        blobs['mask_targets'] = pos_masks
        blobs['mask_weight'] = mask_weight
        blobs['gt_masks_info'] = top_mask_info

    return blobs, fg_inds, bg_inds, keep_inds
示例#4
0
def process_roidb(file_start, file_end, db):

    for cnt in xrange(file_start, file_end):
        f = file_list[cnt]
        full_file = os.path.join(input_dir, f)
        output_cache = os.path.join(output_dir, f.split('.')[0] + '.mat')
        timer_tic = time.time()
        if os.path.exists(output_cache):
            continue
        mcg_mat = sio.loadmat(full_file)
        mcg_mask_label = mcg_mat['labels']
        mcg_superpixels = mcg_mat['superpixels']
        num_proposal = len(mcg_mask_label)
        mcg_boxes = np.zeros((num_proposal, 4))
        mcg_masks = np.zeros((num_proposal, mask_size, mask_size), dtype=np.bool)

        for ind_proposal in xrange(num_proposal):
            label = mcg_mask_label[ind_proposal][0][0]
            proposal = np.in1d(mcg_superpixels, label).reshape(mcg_superpixels.shape)
            [r, c] = np.where(proposal == 1)
            y1 = np.min(r)
            x1 = np.min(c)
            y2 = np.max(r)
            x2 = np.max(c)
            box = np.array([x1, y1, x2, y2])
            proposal = proposal[y1:y2+1, x1:x2+1]
            proposal = cv2.resize(proposal.astype(np.float), (mask_size, mask_size), interpolation=cv2.INTER_NEAREST)
            mcg_masks[ind_proposal, :, :] = proposal
            mcg_boxes[ind_proposal, :] = box

        if top_k != -1:
            mcg_boxes = mcg_boxes[:top_k, :]
            mcg_masks = mcg_masks[:top_k, :]

        if db == 'val':
            # if we prepare validation data, we only need its masks and boxes
            roidb = {
                'masks': (mcg_masks >= cfg.BINARIZE_THRESH).astype(bool),
                'boxes': mcg_boxes
            }
            sio.savemat(output_cache, roidb)
            use_time = time.time() - timer_tic
            print '%d/%d use time %f' % (cnt, len(file_list), use_time)

        else:
            # Otherwise we need to prepare other information like overlaps
            num_mcg = mcg_boxes.shape[0]
            gt_roidb = gt_roidbs[cnt]
            gt_maskdb = gt_maskdbs[cnt]
            gt_boxes = gt_roidb['boxes']
            gt_masks = gt_maskdb['gt_masks']
            gt_classes = gt_roidb['gt_classes']
            num_gt = gt_boxes.shape[0]
            num_all = num_gt + num_mcg
            # define output structure
            det_overlaps = np.zeros((num_all, 1))
            seg_overlaps = np.zeros((num_all, 1))
            seg_assignment = np.zeros((num_all, 1))
            mask_targets = np.zeros((num_all, mask_size, mask_size))
            # ------------------------------------------------------
            all_boxes = np.vstack((gt_boxes[:, :4], mcg_boxes)).astype(int)
            all_masks = np.zeros((num_all, mask_size, mask_size))
            for i in xrange(num_gt):
                all_masks[i, :, :] = (cv2.resize(gt_masks[i].astype(np.float),
                                                (mask_size, mask_size)))
            assert all_masks[num_gt:, :, :].shape == mcg_masks.shape
            all_masks[num_gt:, :, :] = mcg_masks
            # record bounding box overlaps
            cur_overlap = bbox_overlaps(all_boxes.astype(np.float), gt_boxes.astype(np.float))
            seg_assignment = cur_overlap.argmax(axis=1)
            det_overlaps = cur_overlap.max(axis=1)
            seg_assignment[det_overlaps == 0] = -1
            # record mask region overlaps
            seg_overlaps[:num_gt] = 1.0
            for i in xrange(num_gt, num_all):
                cur_mask = cv2.resize(all_masks[i, :, :].astype(np.float),
                                      (all_boxes[i, 2] - all_boxes[i, 0] + 1,
                                       all_boxes[i, 3] - all_boxes[i, 1] + 1)) >= cfg.BINARIZE_THRESH
                for mask_ind in xrange(len(gt_masks)):
                    gt_mask = gt_masks[mask_ind]
                    gt_roi = gt_roidb['boxes'][mask_ind]
                    cur_ov = mask_overlap(all_boxes[i, :], gt_roi, cur_mask, gt_mask)
                    seg_overlaps[i] = max(seg_overlaps[i], cur_ov)

            output_label = np.zeros((num_all, 1))
            for i in xrange(num_all):
                if seg_assignment[i] == -1:
                    continue
                cur_ind = seg_assignment[i]
                output_label[i] = gt_classes[seg_assignment[i]]
                mask_targets[i, :, :] = intersect_mask(all_boxes[i, :], gt_roidb['boxes'][cur_ind], gt_masks[cur_ind])

            # Some of the array need to insert a new axis to be consistent of savemat method
            roidb = {
                'masks': (all_masks >= cfg.BINARIZE_THRESH).astype(bool),
                'boxes': all_boxes,
                'det_overlap': det_overlaps[:, np.newaxis],
                'seg_overlap': seg_overlaps,
                'mask_targets': (mask_targets >= cfg.BINARIZE_THRESH).astype(bool),
                'gt_classes': gt_classes[:, np.newaxis],
                'output_label': output_label,
                'gt_assignment': seg_assignment[:, np.newaxis],
                'Flip': False
            }

            sio.savemat(output_cache, roidb)
            use_time = time.time() - timer_tic
            print '%d/%d use time %f' % (cnt, len(file_list), use_time)
示例#5
0
def process_roidb(file_start, file_end, db):

    for cnt in xrange(file_start, file_end):
        f = file_list[cnt]
        full_file = os.path.join(input_dir, f)
        output_cache = os.path.join(output_dir, f.split('.')[0] + '.mat')
        timer_tic = time.time()
        if os.path.exists(output_cache):
            continue
        mcg_mat = sio.loadmat(full_file)
        mcg_mask_label = mcg_mat['labels']
        mcg_superpixels = mcg_mat['superpixels']
        num_proposal = len(mcg_mask_label)
        mcg_boxes = np.zeros((num_proposal, 4))
        mcg_masks = np.zeros((num_proposal, mask_size, mask_size),
                             dtype=np.bool)

        for ind_proposal in xrange(num_proposal):
            label = mcg_mask_label[ind_proposal][0][0]
            proposal = np.in1d(mcg_superpixels,
                               label).reshape(mcg_superpixels.shape)
            [r, c] = np.where(proposal == 1)
            y1 = np.min(r)
            x1 = np.min(c)
            y2 = np.max(r)
            x2 = np.max(c)
            box = np.array([x1, y1, x2, y2])
            proposal = proposal[y1:y2 + 1, x1:x2 + 1]
            proposal = cv2.resize(proposal.astype(np.float),
                                  (mask_size, mask_size),
                                  interpolation=cv2.INTER_NEAREST)
            mcg_masks[ind_proposal, :, :] = proposal
            mcg_boxes[ind_proposal, :] = box

        if top_k != -1:
            mcg_boxes = mcg_boxes[:top_k, :]
            mcg_masks = mcg_masks[:top_k, :]

        if db == 'val':
            # if we prepare validation data, we only need its masks and boxes
            roidb = {
                'masks': (mcg_masks >= cfg.BINARIZE_THRESH).astype(bool),
                'boxes': mcg_boxes
            }
            sio.savemat(output_cache, roidb)
            use_time = time.time() - timer_tic
            print '%d/%d use time %f' % (cnt, len(file_list), use_time)

        else:
            # Otherwise we need to prepare other information like overlaps
            num_mcg = mcg_boxes.shape[0]
            gt_roidb = gt_roidbs[cnt]
            gt_maskdb = gt_maskdbs[cnt]
            gt_boxes = gt_roidb['boxes']
            gt_masks = gt_maskdb['gt_masks']
            gt_classes = gt_roidb['gt_classes']
            num_gt = gt_boxes.shape[0]
            num_all = num_gt + num_mcg
            # define output structure
            det_overlaps = np.zeros((num_all, 1))
            seg_overlaps = np.zeros((num_all, 1))
            seg_assignment = np.zeros((num_all, 1))
            mask_targets = np.zeros((num_all, mask_size, mask_size))
            # ------------------------------------------------------
            all_boxes = np.vstack((gt_boxes[:, :4], mcg_boxes)).astype(int)
            all_masks = np.zeros((num_all, mask_size, mask_size))
            for i in xrange(num_gt):
                all_masks[i, :, :] = (cv2.resize(gt_masks[i].astype(np.float),
                                                 (mask_size, mask_size)))
            assert all_masks[num_gt:, :, :].shape == mcg_masks.shape
            all_masks[num_gt:, :, :] = mcg_masks
            # record bounding box overlaps
            cur_overlap = bbox_overlaps(all_boxes.astype(np.float),
                                        gt_boxes.astype(np.float))
            seg_assignment = cur_overlap.argmax(axis=1)
            det_overlaps = cur_overlap.max(axis=1)
            seg_assignment[det_overlaps == 0] = -1
            # record mask region overlaps
            seg_overlaps[:num_gt] = 1.0
            for i in xrange(num_gt, num_all):
                cur_mask = cv2.resize(
                    all_masks[i, :, :].astype(np.float),
                    (all_boxes[i, 2] - all_boxes[i, 0] + 1, all_boxes[i, 3] -
                     all_boxes[i, 1] + 1)) >= cfg.BINARIZE_THRESH
                for mask_ind in xrange(len(gt_masks)):
                    gt_mask = gt_masks[mask_ind]
                    gt_roi = gt_roidb['boxes'][mask_ind]
                    cur_ov = mask_overlap(all_boxes[i, :], gt_roi, cur_mask,
                                          gt_mask)
                    seg_overlaps[i] = max(seg_overlaps[i], cur_ov)

            output_label = np.zeros((num_all, 1))
            for i in xrange(num_all):
                if seg_assignment[i] == -1:
                    continue
                cur_ind = seg_assignment[i]
                output_label[i] = gt_classes[seg_assignment[i]]
                mask_targets[i, :, :] = intersect_mask(
                    all_boxes[i, :], gt_roidb['boxes'][cur_ind],
                    gt_masks[cur_ind])

            # Some of the array need to insert a new axis to be consistent of savemat method
            roidb = {
                'masks': (all_masks >= cfg.BINARIZE_THRESH).astype(bool),
                'boxes': all_boxes,
                'det_overlap': det_overlaps[:, np.newaxis],
                'seg_overlap': seg_overlaps,
                'mask_targets':
                (mask_targets >= cfg.BINARIZE_THRESH).astype(bool),
                'gt_classes': gt_classes[:, np.newaxis],
                'output_label': output_label,
                'gt_assignment': seg_assignment[:, np.newaxis],
                'Flip': False
            }

            sio.savemat(output_cache, roidb)
            use_time = time.time() - timer_tic
            print '%d/%d use time %f' % (cnt, len(file_list), use_time)
def _sample_rois(all_rois, gt_boxes, rois_per_image, num_classes, gt_masks,
                 im_scale, mask_info):
    """
    Generate a random sample of RoIs comprising
    foreground and background examples.
    """
    # overlaps: (rois x gt_boxes)
    overlaps = bbox_overlaps(
        np.ascontiguousarray(all_rois[:, 1:5], dtype=np.float),
        np.ascontiguousarray(gt_boxes[:, :4], dtype=np.float))
    gt_assignment = overlaps.argmax(axis=1)
    max_overlaps = overlaps.max(axis=1)
    labels = gt_boxes[gt_assignment, 4]

    # Sample foreground indexes
    fg_inds = []
    for i in xrange(len(cfg.TRAIN.FG_FRACTION)):
        cur_inds = np.where((max_overlaps >= cfg.TRAIN.FG_THRESH_LO[i])
                            & (max_overlaps <= cfg.TRAIN.FG_THRESH_HI[i]))[0]
        cur_rois_this_image = min(
            cur_inds.size, np.round(rois_per_image * cfg.TRAIN.FG_FRACTION[i]))
        if cur_inds.size > 0:
            cur_inds = npr.choice(cur_inds,
                                  size=cur_rois_this_image,
                                  replace=False)
        fg_inds = np.hstack((fg_inds, cur_inds))
        fg_inds = np.unique(fg_inds)
    fg_rois_per_image = fg_inds.size
    # Sample background indexes according to number of foreground
    bg_rois_per_this_image = rois_per_image - fg_rois_per_image
    bg_inds = []
    for i in xrange(len(cfg.TRAIN.BG_FRACTION)):
        cur_inds = np.where((max_overlaps >= cfg.TRAIN.BG_THRESH_LO[i])
                            & (max_overlaps <= cfg.TRAIN.BG_THRESH_HI[i]))[0]
        cur_rois_this_image = min(
            cur_inds.size,
            np.round(bg_rois_per_this_image * cfg.TRAIN.BG_FRACTION[i]))
        if cur_inds.size > 0:
            cur_inds = npr.choice(cur_inds,
                                  size=cur_rois_this_image,
                                  replace=False)
        bg_inds = np.hstack((bg_inds, cur_inds))
        bg_inds = np.unique(bg_inds)

    # The indices that we're selecting (both fg and bg)
    keep_inds = np.append(fg_inds, bg_inds).astype(int)
    # Select sampled values from various arrays:
    labels = labels[keep_inds]
    # Clamp labels for the background RoIs to 0
    labels[fg_rois_per_image:] = 0
    rois = all_rois[keep_inds]

    bbox_target_data = bbox_compute_targets(
        rois[:, 1:5], gt_boxes[gt_assignment[keep_inds], :4], normalize=True)
    bbox_target_data = np.hstack((labels[:, np.newaxis], bbox_target_data))\
        .astype(np.float32, copy=False)
    bbox_targets, bbox_inside_weights = get_bbox_regression_label(
        bbox_target_data, num_classes)
    bbox_outside_weights = np.array(bbox_inside_weights > 0).astype(np.float32)

    blobs = {
        'rois': rois,
        'labels': labels,
        'bbox_targets': bbox_targets,
        'bbox_inside_weights': bbox_inside_weights,
        'bbox_outside_weights': bbox_outside_weights
    }

    if cfg.MNC_MODE:
        scaled_rois = rois[:, 1:5] / float(im_scale)

        # map to original image space
        scaled_gt_boxes = gt_boxes[:, :4] / float(im_scale)
        pos_masks = np.zeros((len(keep_inds), 1, cfg.MASK_SIZE, cfg.MASK_SIZE))
        top_mask_info = np.zeros((len(keep_inds), 12))
        top_mask_info[len(fg_inds):, :] = -1

        for i, val in enumerate(fg_inds):
            gt_box = scaled_gt_boxes[gt_assignment[val]]
            gt_box = np.around(gt_box).astype(int)
            ex_box = np.around(scaled_rois[i]).astype(int)
            gt_mask = gt_masks[gt_assignment[val]]
            gt_mask_info = mask_info[gt_assignment[val]]
            gt_mask = gt_mask[0:gt_mask_info[0], 0:gt_mask_info[1]]
            # calculate mask regression targets
            # (intersection of bounding box and gt mask)
            ex_mask = intersect_mask(ex_box, gt_box, gt_mask)

            pos_masks[i, ...] = ex_mask
            top_mask_info[i, 0] = gt_assignment[val]
            top_mask_info[i, 1] = gt_mask_info[0]
            top_mask_info[i, 2] = gt_mask_info[1]
            top_mask_info[i, 3] = labels[i]

            top_mask_info[i, 4:8] = ex_box
            top_mask_info[i, 8:12] = gt_box

        mask_weight = np.zeros(
            (rois.shape[0], 1, cfg.MASK_SIZE, cfg.MASK_SIZE))
        # only assign box-level foreground as positive mask regression
        mask_weight[0:len(fg_inds), :, :, :] = 1
        blobs['mask_targets'] = pos_masks
        blobs['mask_weight'] = mask_weight
        blobs['gt_masks_info'] = top_mask_info

    return blobs, fg_inds, bg_inds, keep_inds