Roozbeh Mottaghi, Yu Xiang, and Silvio Savarese · Roozbeh Mottaghi, Yu Xiang, and Silvio Savarese...

1
A Unified Framework for Object Detection, Pose Estimation, and Sub-category Recognition Roozbeh Mottaghi, Yu Xiang, and Silvio Savarese Our goal is to detect objects in images. In addition to the object bounding box, we are interested in estimating its viewpoint (e.g., it is critical for autonomous driving applications). We also find the sub-category of the object and provide finer details for the detected object. Summary Car Truck Aeroplane Fighter Hierarchical Model Top Layer Middle Layer Bottom Layer Dataset For training and evaluating our method we required a large scale 3D dataset. Hence, we annotated around 30,000 images with 3D information [1]. elevation distance azimuth References [1] Y. Xiang, R. Mottaghi, and S. Savarese. Beyond PASCAL: A Benchmark for 3D Object Detection in the Wild. In WACV 2014. [2] P. F. Felzenszwalb, R. B. Girshick, D. McAllester, and D. Ramanan. Object detection with discriminatively trained part based models. In PAMI, 2010. Approach We formulate the problem as a structured learning problem. a: azimuth, e: elevation, d: distance, : mid-layer category, : fine-layer category, o: object type is the feature vector, and is the learned weight. The hierarchy allows us to break down the problem into easier chunks. Also, the joint modeling of these tasks with a hierarchy enables us to better recover from the mistakes that a single layer makes. coarse to fine hierarchy car race SUV race 1 race 2 Results We evaluate our method on PASCAL 3D+ dataset, which is a challenging benchmark. The evaluation is done for all three tasks: detection, pose estimation, and sub-category recognition. Detection (AP) Viewpoint Sub-category Viewpoint + Sub-category Viewpoint + Sub-category+ Sub-sub-category DPM [2] 32.0 33.3 16.5 6.5 0.8 Hierarchical Model 41.1 45.9 26.1 11.9 1.9 We use histogram of oriented gradients (HOG) and convolutional neural network features. Failure Cases

Transcript of Roozbeh Mottaghi, Yu Xiang, and Silvio Savarese · Roozbeh Mottaghi, Yu Xiang, and Silvio Savarese...

Page 1: Roozbeh Mottaghi, Yu Xiang, and Silvio Savarese · Roozbeh Mottaghi, Yu Xiang, and Silvio Savarese • Our goal is to detect objects in images. • In addition to the object bounding

A Unified Framework for Object Detection, Pose Estimation, and Sub-category Recognition Roozbeh Mottaghi, Yu Xiang, and Silvio Savarese

• Our goal is to detect objects in images.

• In addition to the object bounding box, we are interested

in estimating its viewpoint (e.g., it is critical for

autonomous driving applications).

• We also find the sub-category of the object and provide

finer details for the detected object.

Summary

Car

Truck Aeroplane

Fighter

Hierarchical Model

Top Layer

Middle Layer

Bottom Layer

Dataset

• For training and evaluating our method we required a

large scale 3D dataset. Hence, we annotated around

30,000 images with 3D information [1].

elevation

distance

azimuth

References

[1] Y. Xiang, R. Mottaghi, and S. Savarese. Beyond PASCAL: A

Benchmark for 3D Object Detection in the Wild. In WACV 2014.

[2] P. F. Felzenszwalb, R. B. Girshick, D. McAllester, and D.

Ramanan. Object detection with discriminatively trained part

based models. In PAMI, 2010.

Approach

•We formulate the problem as a structured learning

problem.

a: azimuth, e: elevation, d: distance, : mid-layer

category, : fine-layer category, o: object type

is the feature vector, and is the learned weight.

• The hierarchy allows us to break down the problem into

easier chunks. Also, the joint modeling of these tasks

with a hierarchy enables us to better recover from the

mistakes that a single layer makes.

coarse to fine hierarchy

car

race SUV

race 1 race 2

Results

• We evaluate our method on PASCAL 3D+ dataset, which

is a challenging benchmark.

• The evaluation is done for all three tasks: detection,

pose estimation, and sub-category recognition.

Detection (AP)

Viewpoint Sub-category Viewpoint + Sub-category

Viewpoint + Sub-category+

Sub-sub-category

DPM [2] 32.0 33.3 16.5 6.5 0.8 Hierarchical

Model 41.1 45.9 26.1 11.9 1.9

We use histogram of oriented

gradients (HOG) and convolutional

neural network features.

Failure Cases