Papers › A Geometric Approach to Obtain a Bird's Eye View from an Image

A Geometric Approach to Obtain a Bird's Eye View from an Image

6 May 2019arXiv:1905.02231archive 2025-07-28

Ammar Abbas, Andrew Zisserman

The objective of this paper is to rectify any monocular image by computing a homography matrix that transforms it to a bird's eye (overhead) view. We make the following contributions: (i) we show that the homography matrix can be parameterised with only four parameters that specify the horizon line and the vertical vanishing point, or only two if the field of view or focal length is known; (ii) We introduce a novel representation for the geometry of a line or point (which can be at infinity) that is suitable for regression with a convolutional neural network (CNN); (iii) We introduce a large synthetic image dataset with ground truth for the orthogonal vanishing points, that can be used for training a CNN to predict these geometric entities; and finally (iv) We achieve state-of-the-art results on horizon detection, with 74.52% AUC on the Horizon Lines in the Wild dataset. Our method is fast and robust, and can be used to remove perspective distortion from videos in real time.

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wrapped_partial SAmmarAbbas/birds-eye-view/nets/mobilenet_v1.py official repository ran Apache-2.0 (permissive) · b6e06004f7efe660 · report
get_abcline_from_two_points SAmmarAbbas/birds-eye-view/utils/geometry.py official repository unverified Apache-2.0 (permissive) · fe63b14b45f4dc1b · report
get_point_on_2pointline_normal_to_3rdpoint SAmmarAbbas/birds-eye-view/utils/projection.py official repository unverified Apache-2.0 (permissive) · cae34523b46e1666 · report
get_point_on_sphere_normal_to_plane SAmmarAbbas/birds-eye-view/utils/projection.py official repository unverified Apache-2.0 (permissive) · 1515b9ba2356962c · report
get_projection_on_sphere SAmmarAbbas/birds-eye-view/utils/projection.py official repository unverified Apache-2.0 (permissive) · 731aee05bcf54013 · report
get_slope_intercept_from_abc_line SAmmarAbbas/birds-eye-view/utils/geometry.py official repository unverified Apache-2.0 (permissive) · 420ab89b99034648 · report
preprocess_for_eval SAmmarAbbas/birds-eye-view/preprocessing/vgg_preprocessing.py official repository unverified Apache-2.0 (permissive) · 9d85e040f6eb6b96 · report
preprocess_for_train SAmmarAbbas/birds-eye-view/preprocessing/vgg_preprocessing.py official repository unverified Apache-2.0 (permissive) · e5e1627b9d206d2e · report
preprocess_image SAmmarAbbas/birds-eye-view/preprocessing/vgg_preprocessing.py official repository unverified Apache-2.0 (permissive) · bc061bfb32babd6d · report
resize_image_with_vps SAmmarAbbas/birds-eye-view/utils/images.py official repository unverified Apache-2.0 (permissive) · 24f28b7c4fff4754 · report
scale_abcline SAmmarAbbas/birds-eye-view/utils/geometry.py official repository unverified Apache-2.0 (permissive) · f6f639da7e199940 · report

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