This op produces Region of Interests from given bounding boxes(bbox_deltas) encoded wrt anchors according to eq.2 in arXiv:1506.01497
tf.raw_ops.GenerateBoundingBoxProposals(
    scores, bbox_deltas, image_info, anchors, nms_threshold, pre_nms_topn, min_size,
    post_nms_topn=300, name=None
)
  The op selects top `pre_nms_topn` scoring boxes, decodes them with respect to anchors,
  applies non-maximal suppression on overlapping boxes with higher than
  `nms_threshold` intersection-over-union (iou) value, discarding boxes where shorter
  side is less than `min_size`.
  Inputs:
  `scores`: A 4D tensor of shape [Batch, Height, Width, Num Anchors] containing the scores per anchor at given position
  `bbox_deltas`: is a tensor of shape [Batch, Height, Width, 4 x Num Anchors] boxes encoded to each anchor
  `anchors`: A 1D tensor of shape [4 x Num Anchors], representing the anchors.
  Outputs:
  `rois`: output RoIs, a 3D tensor of shape [Batch, post_nms_topn, 4], padded by 0 if less than post_nms_topn candidates found.
  `roi_probabilities`: probability scores of each roi in 'rois', a 2D tensor of shape [Batch,post_nms_topn], padded with 0 if needed, sorted by scores.
| Args | 
|---|
| scores | A Tensorof typefloat32.
A 4-D float tensor of shape[num_images, height, width, num_achors]containing scores of the boxes for given anchors, can be unsorted. | 
| bbox_deltas | A Tensorof typefloat32.
A 4-D float tensor of shape[num_images, height, width, 4 x num_anchors]. encoding boxes with respec to each anchor.
Coordinates are given in the form [dy, dx, dh, dw]. | 
| image_info | A Tensorof typefloat32.
A 2-D float tensor of shape[num_images, 5]containing image information Height, Width, Scale. | 
| anchors | A Tensorof typefloat32.
A 2-D float tensor of shape[num_anchors, 4]describing the anchor boxes. Boxes are formatted in the form [y1, x1, y2, x2]. | 
| nms_threshold | A Tensorof typefloat32.
A scalar float tensor for non-maximal-suppression threshold. | 
| pre_nms_topn | A Tensorof typeint32.
A scalar int tensor for the number of top scoring boxes to be used as input. | 
| min_size | A Tensorof typefloat32.
A scalar float tensor. Any box that has a smaller size than min_size will be discarded. | 
| post_nms_topn | An optional int. Defaults to300.
An integer. Maximum number of rois in the output. | 
| name | A name for the operation (optional). | 
| Returns | 
|---|
| A tuple of Tensorobjects (rois, roi_probabilities). | 
| rois | A Tensorof typefloat32. | 
| roi_probabilities | A Tensorof typefloat32. |