Bundling interest points for object classification

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BSc thesis by Jordi Sánchez Escué. ETSETB UPC (25/07/2014) More details:

Transcript of Bundling interest points for object classification

Bundling interest points for object classification

Jordi Sánchez Escué

Supervised byXavier Giró i Nieto

Carles Ventura Royo

Contents● Introduction● State of the art● System Architecture

○ Feature extraction○ Classification○ Evaluation

● Experiments○ Class aggregation of interest points○ Bundling interest points○ Class aggregation & Bundling

● Conclusions & Future work1

Contents● Introduction● State of the art● System Architecture

○ Feature extraction○ Classification○ Evaluation

● Experiments○ Class aggregation of interest points○ Bundling interest points○ Class aggregation & Bundling

● Conclusions & Future work2

Introduction● Does this image contain a plane?

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Introduction● Does this image contain a plane?

● Which type of flower is it?

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Introduction● Mobile Visual Search

○ Generalist: Google Goggles

○ Leaf-based: Leafsnap

● Fine-grained classification○ Mushrooms

○ Flowers

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Introduction● Textures around some interest points

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Introduction● Features based on regions

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Introduction● Explore combination: points & regions

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Introduction● Project Requirements and Goals

○ Comparative study bundling interest points

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Introduction● Project Requirements and Goals

○ Software Development

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Contents● Introduction● State of the art● System Architecture

○ Feature extraction○ Classification○ Evaluation

● Experiments○ Class aggregation of interest points○ Bundling interest points○ Class aggregation & Bundling

● Conclusions & Future work11

State of the art● In Defense of Nearest-Neighbor Based

Image Classification, Oren Boiman

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State of the art● Building contextual visual vocabulary for

large-scale image applications, S. Zhang

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Contents● Introduction● State of the art● System Architecture

○ Feature extraction○ Classification○ Evaluation

● Experiments○ Class aggregation of interest points○ Bundling interest points○ Class aggregation & Bundling

● Conclusions & Future work14

System Architecture● Interest points and feature extraction

○ Sparse extraction

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System Architecture● Interest points and feature extraction

○ Interest Points: SURF

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System Architecture● Binary Partition Tree (BPT)

○ Partition: 20 reg. SLIC

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● Binary Partition Tree○ A scale is chosen (ex, N = 3)

System Architecture

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Contents● Introduction● State of the art● System Architecture

○ Feature extraction○ Classification○ Evaluation

● Experiments○ Class aggregation of interest points○ Bundling interest points○ Class aggregation & Bundling

● Conclusions & Future work19

System Architecture● Classification: Training

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Trainer

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System Architecture

CLASSIFIER1-NN, euclidean

distance

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● Classification: Detection

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Target image

System Architecture

Query image

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System Architecture

Target image

Query image

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System Architecture

Query image

Target image

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System Architecture

Query image

Target image

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System Architecture

Query image

Target image

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System Architecture

Query image

Target image

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System Architecture

Query image

Nearest Target image11

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Contents● Introduction● State of the art● System Architecture

○ Feature extraction○ Classification○ Evaluation

● Experiments○ Class aggregation of interest points○ Bundling interest points○ Class aggregation & Bundling

● Conclusions & Future work29

System Architecture● Evaluation

○ Development of an evaluation tool

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Tools

System Architecture● Software development

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Trainer

Detector

Evaluation

SVM adapted to a flexible architecture

New tool for evaluation

Can be adapted to any classifier

or descriptor

Contents● Introduction● State of the art● System Architecture

○ Feature extraction○ Classification○ Evaluation

● Experiments○ Class aggregation of interest points○ Bundling interest points○ Class aggregation & Bundling

● Conclusions & Future work32

M-E. Nilsback & A. Zisserman, «A Visual Vocabulary for Flower Classification» Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, 2006. http://www.robots.ox.ac.uk/~vgg/data/flowers/17/

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0.591769

0.3813720.463660

Experiments: basic approach● Results

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Contents● Introduction● State of the art● System Architecture

○ Feature extraction○ Classification○ Evaluation

● Experiments○ Class aggregation of interest points○ Bundling interest points○ Class aggregation & Bundling

● Conclusions & Future work35

Experiments: Class aggregation● Aggregation of the interest points of all the

images of the same class to do the matching

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Experiments: Class aggregation● Results

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Contents● Introduction● State of the art● System Architecture

○ Feature extraction○ Classification○ Evaluation

● Experiments○ Class aggregation of interest points○ Bundling interest points○ Class aggregation & Bundling

● Conclusions & Future work38

● Region restriction

Experiments: Bundling interest points

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Experiments: Bundling interest points

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● Why the results did not improve?○ Image flower segmentation

Experiments: Bundling interest points

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● Why the results did not improve?○ Bad flower segmentation (N = 2)

Experiments: Bundling interest points

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● Why the results did not improve?○ Bad flower segmentation (N = 2)

● Future work to improve results○ Using perfect manual segmentation

Experiments: Bundling interest points

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● Why the results did not improve?○ Good region matching (flower to flower)

Experiments: Bundling interest points

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● Why the results did not improve?○ Bad region matching (flower to background)

Experiments: Bundling interest points

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● Why the results did not improve?○ Bad region matching (flower to background)

● Future work to improve results○ Avoid using edge regions

○ Using object candidates

Experiments: Bundling interest points

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Contents● Introduction● State of the art● System Architecture

○ Feature extraction○ Classification○ Evaluation

● Experiments○ Class aggregation of interest points○ Bundling interest points○ Class aggregation & Bundling

● Conclusions & Future work47

Experiments: Class aggregation & Bundling

● Class aggregation with points bundled in regions

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● Comparative study

Experiments: Class aggregation & Bundling

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Contents● Introduction● State of the art● System Architecture

○ Feature extraction○ Classification○ Evaluation

● Experiments○ Class aggregation of interest points○ Bundling interest points○ Class aggregation & Bundling

● Conclusions & Future work50

Conclusions & Future Work● Comparative study done

○ Bundling interest points into regions worsens the F1-score between 1% and 7%

○ Class aggregation improves the F1-score by 9.2%

● State of the art comparative study

○ Pointless having bad results

● Software development

● Future Work51

Bundling interest points for object classification

Jordi Sánchez Escué

Supervised byXavier Giró i Nieto

Carles Ventura Royo

System Architecture● Classification: Training

○ Semantic annotation & Ontology

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System Architecture● Binary Partition Tree (BPT)

○ 20 SLIC superpixels

Future work● Add new approaches

○ Class aggregation in the query

○ Bundling query image, not bundling target

images (with certain spatial restriction).

● Optimize k, change classifier, more descriptors