ACP based face detection Ramin Marx 1 Mai 2007 1 with support from - - PowerPoint PPT Presentation

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ACP based face detection Ramin Marx 1 Mai 2007 1 with support from - - PowerPoint PPT Presentation

Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software ACP based face detection Ramin Marx 1 Mai 2007 1 with support from Jean-Marc Bo and Bernard Fertil Ramin Marx ACP based face


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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

ACP based face detection

Ramin Marx 1 Mai 2007

1with support from Jean-Marc Bo¨

ı and Bernard Fertil

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Introduction

Situation many domains deal with human faces (video surveillance, identification)

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Introduction

Situation many domains deal with human faces (video surveillance, identification) Problems humans in the picture? or not? where?

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Introduction

Situation many domains deal with human faces (video surveillance, identification) Problems humans in the picture? or not? where? Goal algorithm, which locates faces in a given picture

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Input picture

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Output picture

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Approach

◮ calculate the faceness of a region R

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Approach

◮ calculate the faceness of a region R ◮ analyze a training database with a huge number of faces

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Approach

◮ calculate the faceness of a region R ◮ analyze a training database with a huge number of faces ◮ extract the most characteristic features and find out how

many of those features contains R

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

Idea

◮ treat each of the face images (size n × m) as vector

v ∈ Rn·m

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

Idea

◮ treat each of the face images (size n × m) as vector

v ∈ Rn·m

◮ find relationships between dimensions by calculating the

covariances of the training faces

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

Idea

◮ treat each of the face images (size n × m) as vector

v ∈ Rn·m

◮ find relationships between dimensions by calculating the

covariances of the training faces

◮ calculate the eigenvectors of that covariance matrix and sort

them descending according to their eigenvalues

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

Idea

◮ treat each of the face images (size n × m) as vector

v ∈ Rn·m

◮ find relationships between dimensions by calculating the

covariances of the training faces

◮ calculate the eigenvectors of that covariance matrix and sort

them descending according to their eigenvalues

◮ new base, in which the i-th base vector contains i-th most

information about the data set

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

Idea

◮ treat each of the face images (size n × m) as vector

v ∈ Rn·m

◮ find relationships between dimensions by calculating the

covariances of the training faces

◮ calculate the eigenvectors of that covariance matrix and sort

them descending according to their eigenvalues

◮ new base, in which the i-th base vector contains i-th most

information about the data set

◮ we take the first M base vectors and obtain a hyperplane

H ⊂ Rn·m

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

Idea

◮ treat each of the face images (size n × m) as vector

v ∈ Rn·m

◮ find relationships between dimensions by calculating the

covariances of the training faces

◮ calculate the eigenvectors of that covariance matrix and sort

them descending according to their eigenvalues

◮ new base, in which the i-th base vector contains i-th most

information about the data set

◮ we take the first M base vectors and obtain a hyperplane

H ⊂ Rn·m

◮ H is the M-dimensional face space, all face vectors lie very

close to it

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

The faceness-test

◮ face vector

v lies close to H ⇔ their distance is small

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

The faceness-test

◮ face vector

v lies close to H ⇔ their distance is small

◮ but what is the distance between

v and H?

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

The faceness-test

◮ face vector

v lies close to H ⇔ their distance is small

◮ but what is the distance between

v and H?

◮ it is the (Euclidian) distance between

v and its projection

  • vH ⊂ H

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

The faceness-test

◮ face vector

v lies close to H ⇔ their distance is small

◮ but what is the distance between

v and H?

◮ it is the (Euclidian) distance between

v and its projection

  • vH ⊂ H

◮ problem:

v and vH have different bases

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

The faceness-test

◮ face vector

v lies close to H ⇔ their distance is small

◮ but what is the distance between

v and H?

◮ it is the (Euclidian) distance between

v and its projection

  • vH ⊂ H

◮ problem:

v and vH have different bases

◮ solution: transform

vH back to Rn·m and then calculate the distance

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

Which parameters are interesting?

We have to analyze what impacts

◮ the number of images in the database M,

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

Which parameters are interesting?

We have to analyze what impacts

◮ the number of images in the database M, ◮ the number of pricipal components M′ to choose,

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

Which parameters are interesting?

We have to analyze what impacts

◮ the number of images in the database M, ◮ the number of pricipal components M′ to choose, ◮ the comparison algorithm which test the simiarity between

  • riginal and reconstructed image,

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

Which parameters are interesting?

We have to analyze what impacts

◮ the number of images in the database M, ◮ the number of pricipal components M′ to choose, ◮ the comparison algorithm which test the simiarity between

  • riginal and reconstructed image,

◮ and the size of the images in the database have.

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

Tests

All in all, we want to know how the PCA reacts on

◮ images which contain faces from the database,

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

Tests

All in all, we want to know how the PCA reacts on

◮ images which contain faces from the database, ◮ images which contain faces not in the database,

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software PCA Parameters

Tests

All in all, we want to know how the PCA reacts on

◮ images which contain faces from the database, ◮ images which contain faces not in the database, ◮ and on images which contain no faces at all.

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 1

Database Olivetti Research Laboratory face database, which contains 400 pictures of faces (40 individuals, 10 poses)

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 1

Database Olivetti Research Laboratory face database, which contains 400 pictures of faces (40 individuals, 10 poses) Test 1 100 faces from the database,

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 1

Database Olivetti Research Laboratory face database, which contains 400 pictures of faces (40 individuals, 10 poses) Test 1 100 faces from the database, Test 2 100 faces not in the database

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 1

Database Olivetti Research Laboratory face database, which contains 400 pictures of faces (40 individuals, 10 poses) Test 1 100 faces from the database, Test 2 100 faces not in the database Test 3 30 non-face pictures

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Sample pictures with faces from the database

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Sample pictures from faces not in the database

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Sample pictures from non-faces

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

After having made the Principle Component Analysis of our data set with the 300 face images, we take a look at our new base vectors, the Eigenfaces.

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Eigenfaces 1 . . . 10 and 20, 25, 30, 40, . . . , 100, 150, 200, 250 and 300.

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Start of experiment

Now, we will

◮ take a sample picture,

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Start of experiment

Now, we will

◮ take a sample picture, ◮ project it onto the n-dimensional face space,

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Start of experiment

Now, we will

◮ take a sample picture, ◮ project it onto the n-dimensional face space, ◮ vary n from 1 to 300 and

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Start of experiment

Now, we will

◮ take a sample picture, ◮ project it onto the n-dimensional face space, ◮ vary n from 1 to 300 and ◮ consider the reconstruction error (distance between n and its

projection).

Ramin Marx ACP based face detection

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dist(original,projection) for the DB-face (lower curve) the non-DB face (upper curve) and the non-face (middle curve).

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Results

◮ the more Eigenfaces are used, the better is the reconstruction

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Results

◮ the more Eigenfaces are used, the better is the reconstruction ◮ face from database can be perfectly reconstructed

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Results

◮ the more Eigenfaces are used, the better is the reconstruction ◮ face from database can be perfectly reconstructed ◮ non-DB face and non-face can also be reconstructed (but not

perfectly)

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Results

◮ the more Eigenfaces are used, the better is the reconstruction ◮ face from database can be perfectly reconstructed ◮ non-DB face and non-face can also be reconstructed (but not

perfectly)

◮ the non-face can be better reconstructed than the non-DB

face

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Results

◮ the more Eigenfaces are used, the better is the reconstruction ◮ face from database can be perfectly reconstructed ◮ non-DB face and non-face can also be reconstructed (but not

perfectly)

◮ the non-face can be better reconstructed than the non-DB

face

◮ that is bad - we expected the opposite

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Results

◮ the more Eigenfaces are used, the better is the reconstruction ◮ face from database can be perfectly reconstructed ◮ non-DB face and non-face can also be reconstructed (but not

perfectly)

◮ the non-face can be better reconstructed than the non-DB

face

◮ that is bad - we expected the opposite ◮ but one image is not representative → repeat with more

Ramin Marx ACP based face detection

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100 faces from the DB 100 faces not from DB 30 non-faces Average

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Closer look at the average picture

many pictures, but the same result: non-faces images are assigned a higher faceness than non-DB faces

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Possible explanation

◮ why are the non-face images closer to the face space than the

non-DB faces?

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Possible explanation

◮ why are the non-face images closer to the face space than the

non-DB faces?

◮ perhaps non-DB faces got a low faceness value because of

disturbing background?

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Possible explanation

◮ why are the non-face images closer to the face space than the

non-DB faces?

◮ perhaps non-DB faces got a low faceness value because of

disturbing background?

◮ apply a mask!

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Possible explanation

◮ why are the non-face images closer to the face space than the

non-DB faces?

◮ perhaps non-DB faces got a low faceness value because of

disturbing background?

◮ apply a mask!

− →

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 2

◮ we repeat the experiment with exactly the same parameters

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 2

◮ we repeat the experiment with exactly the same parameters ◮ except that we apply a mask :-)

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 2

◮ we repeat the experiment with exactly the same parameters ◮ except that we apply a mask :-) ◮ unfortunately, almost exactly the same results

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 2

◮ we repeat the experiment with exactly the same parameters ◮ except that we apply a mask :-) ◮ unfortunately, almost exactly the same results ◮ explanation: because the DB was big enough, the PCA was

able to ’ignore’ those unimportant border pixels (that means: don’t consider them while creating the face space)

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 3

Database AT&T Face Database, we use 50 pictures of faces (20 individuals, ca. 3 poses)

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 3

Database AT&T Face Database, we use 50 pictures of faces (20 individuals, ca. 3 poses) Difference 1 images are illuminated differently → more robust

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 3

Database AT&T Face Database, we use 50 pictures of faces (20 individuals, ca. 3 poses) Difference 1 images are illuminated differently → more robust Difference 2 resolution is much higher (250 × 300 instead of 32 × 32)

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 3

Database AT&T Face Database, we use 50 pictures of faces (20 individuals, ca. 3 poses) Difference 1 images are illuminated differently → more robust Difference 2 resolution is much higher (250 × 300 instead of 32 × 32) Difference 3 none of the faces have a background; only the face is visible

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 3

Database AT&T Face Database, we use 50 pictures of faces (20 individuals, ca. 3 poses) Difference 1 images are illuminated differently → more robust Difference 2 resolution is much higher (250 × 300 instead of 32 × 32) Difference 3 none of the faces have a background; only the face is visible Test 1 30 faces from the database

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 3

Database AT&T Face Database, we use 50 pictures of faces (20 individuals, ca. 3 poses) Difference 1 images are illuminated differently → more robust Difference 2 resolution is much higher (250 × 300 instead of 32 × 32) Difference 3 none of the faces have a background; only the face is visible Test 1 30 faces from the database Test 2 30 faces not in the database

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 3

Database AT&T Face Database, we use 50 pictures of faces (20 individuals, ca. 3 poses) Difference 1 images are illuminated differently → more robust Difference 2 resolution is much higher (250 × 300 instead of 32 × 32) Difference 3 none of the faces have a background; only the face is visible Test 1 30 faces from the database Test 2 30 faces not in the database Test 3 30 non-face pictures

Ramin Marx ACP based face detection

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Sample pictures of the AT&T database

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Recostruction errors of DB-faces, non-DB-faces and non-faces

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Average reconstruction errors

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Results

◮ 20-25 Eigenfaces are enough to distinguish a face from the

DB from any other structure.

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Results

◮ 20-25 Eigenfaces are enough to distinguish a face from the

DB from any other structure.

◮ again problems in distinguishing non-DB-faces from non-faces.

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 4

◮ we repeat the experiment with the same parameters

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 4

◮ we repeat the experiment with the same parameters ◮ but we reduce the resolution to (37x44) to find out if the

results of the PCA depend on the dimension of the input data

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software Experiment 1 Experiment 2 Experiment 3 Experiment 4

Experiment 4

◮ we repeat the experiment with the same parameters ◮ but we reduce the resolution to (37x44) to find out if the

results of the PCA depend on the dimension of the input data

◮ as expected: the same result

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Questions and conclusions

◮ Why does the PCA react so much on certain non-face images?

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Questions and conclusions

◮ Why does the PCA react so much on certain non-face images? ◮ How to improve the method to compare original picture with

reconstructed picture? Perhaps there are better methods than calculating the Euclidian distance.

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Questions and conclusions

◮ Why does the PCA react so much on certain non-face images? ◮ How to improve the method to compare original picture with

reconstructed picture? Perhaps there are better methods than calculating the Euclidian distance.

◮ As the curves suggest, the PCA seems to be better suited for

face recognition than for face detection, because it can very well distinguish between DB-face and any other image, but not between non-DB-faces and non-faces.

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Questions and conclusions

◮ Why does the PCA react so much on certain non-face images? ◮ How to improve the method to compare original picture with

reconstructed picture? Perhaps there are better methods than calculating the Euclidian distance.

◮ As the curves suggest, the PCA seems to be better suited for

face recognition than for face detection, because it can very well distinguish between DB-face and any other image, but not between non-DB-faces and non-faces.

◮ Although histogram stretching was used, could more

sophisticated preprocessing improve the results?

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Questions and conclusions

◮ Why does the PCA react so much on certain non-face images? ◮ How to improve the method to compare original picture with

reconstructed picture? Perhaps there are better methods than calculating the Euclidian distance.

◮ As the curves suggest, the PCA seems to be better suited for

face recognition than for face detection, because it can very well distinguish between DB-face and any other image, but not between non-DB-faces and non-faces.

◮ Although histogram stretching was used, could more

sophisticated preprocessing improve the results?

◮ If the above problems were all solved, which heuristics could

be used to increase the speed?

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Face Detection Program

◮ Designed to find faces of any size.

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Face Detection Program

◮ Designed to find faces of any size. ◮ Masks can be applied.

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Face Detection Program

◮ Designed to find faces of any size. ◮ Masks can be applied. ◮ Different face databases can be easily used.

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Face Detection Program

◮ Designed to find faces of any size. ◮ Masks can be applied. ◮ Different face databases can be easily used. ◮ Heuristics are used which increase the speed about a factor of

20000 (search for regions which are similar to the structure of human eyes)

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Face Detection Program

◮ Designed to find faces of any size. ◮ Masks can be applied. ◮ Different face databases can be easily used. ◮ Heuristics are used which increase the speed about a factor of

20000 (search for regions which are similar to the structure of human eyes)

◮ . . .

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Face Detection Program

◮ Designed to find faces of any size. ◮ Masks can be applied. ◮ Different face databases can be easily used. ◮ Heuristics are used which increase the speed about a factor of

20000 (search for regions which are similar to the structure of human eyes)

◮ . . . ◮ but because of the results obtained above, too many non-face

regions are classified as faces and that’s why the program is useless at the moment

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Used papers/software

◮ GNU Scientific Library for matrix calculations like finding

eigenvectors

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Used papers/software

◮ GNU Scientific Library for matrix calculations like finding

eigenvectors

◮ M. Turk and A. Pentland (1991). ’Face recognition using

eigenfaces’. Proc. IEEE Conference on Computer Vision and Pattern Recognition: 586-591. (PDF file available)

Ramin Marx ACP based face detection

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Introduction Analysis Experiments Questions and conclusions Face Detection Program Used Papers/Software

Used papers/software

◮ GNU Scientific Library for matrix calculations like finding

eigenvectors

◮ M. Turk and A. Pentland (1991). ’Face recognition using

eigenfaces’. Proc. IEEE Conference on Computer Vision and Pattern Recognition: 586-591. (PDF file available)

◮ http://en.wikipedia.org/wiki/Eigenface and many other

web-pages on PCA, Eigenfaces and face detection

Ramin Marx ACP based face detection