https://github.com/facebookresearch/pythia
Tip revision: dabf95f523cd07e93380c6931e5140ade0f50b2f authored by Sethu Sankaran on 26 October 2021, 19:18:43 UTC
Revert D30704069: [feat] Add a refiner head that can be used with MMFT
Revert D30704069: [feat] Add a refiner head that can be used with MMFT
Tip revision: dabf95f
box_ops.py
# Copyright (c) Facebook, Inc. and its affiliates.
# Mostly copy-pasted from
# https://github.com/facebookresearch/detr/blob/master/util/box_ops.py
import torch
from torch import Tensor
from torchvision.ops.boxes import box_area
def box_cxcywh_to_xyxy(x: Tensor):
x_c, y_c, w, h = x.unbind(-1)
b = [(x_c - 0.5 * w), (y_c - 0.5 * h), (x_c + 0.5 * w), (y_c + 0.5 * h)]
return torch.stack(b, dim=-1)
def box_xyxy_to_cxcywh(x: Tensor):
x0, y0, x1, y1 = x.unbind(-1)
b = [(x0 + x1) / 2, (y0 + y1) / 2, (x1 - x0), (y1 - y0)]
return torch.stack(b, dim=-1)
def box_iou(boxes1: Tensor, boxes2: Tensor):
area1 = box_area(boxes1)
area2 = box_area(boxes2)
lt = torch.max(boxes1[:, None, :2], boxes2[:, :2]) # [N,M,2]
rb = torch.min(boxes1[:, None, 2:], boxes2[:, 2:]) # [N,M,2]
wh = (rb - lt).clamp(min=0) # [N,M,2]
inter = wh[:, :, 0] * wh[:, :, 1] # [N,M]
union = area1[:, None] + area2 - inter
iou = inter / union
return iou, union
def generalized_box_iou(boxes1: Tensor, boxes2: Tensor):
"""
Generalized IoU from https://giou.stanford.edu/
The boxes should be in [x0, y0, x1, y1] format
Returns a [N, M] pairwise matrix, where N = len(boxes1)
and M = len(boxes2)
"""
# degenerate boxes gives inf / nan results
# so do an early check
assert (boxes1[:, 2:] >= boxes1[:, :2]).all()
assert (boxes2[:, 2:] >= boxes2[:, :2]).all()
iou, union = box_iou(boxes1, boxes2)
lt = torch.min(boxes1[:, None, :2], boxes2[:, :2])
rb = torch.max(boxes1[:, None, 2:], boxes2[:, 2:])
wh = (rb - lt).clamp(min=0) # [N,M,2]
area = wh[:, :, 0] * wh[:, :, 1]
return iou - (area - union) / area