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Thumbprint Gabor Filtering, Orientation Map and Normalization

Hi everyone,

I have been working through the steps of fingerprint matching presented in an answer here: http://answers.opencv.org/question/6364/fingerprint-matching-in-mobile-devices-android-platform/ Some of the links provided in the answer are now dead and I cannot find examples online. I have figured out how to perform some steps, but there are a few I am struggling with.

For the blockwise gabor filtering, can someone provide me an example or the parameters I should use? (All the images I am using are size 388x374)

Before filtering the images and creating the skeleton map, I would like to somehow normalize the images. Ideally I would like to center each thumbprint based on some reference point. It seems like creating an orientation map may be how to accomplish this step. If so, can someone provide so example/help to obtain the orientation map? Once i have obtained the orientation map how can I use it to find a reference point?

Thank you for your help

Thumbprint Gabor Filtering, Orientation Map and Normalization

Hi everyone,

I have been working through the steps of fingerprint matching presented in an answer here: http://answers.opencv.org/question/6364/fingerprint-matching-in-mobile-devices-android-platform/ http://answers.opencv.org/question/6364/fingerprint-matching-in-mobile-devices-android-platform/

Some of the links provided in the answer are now dead and I cannot find examples online. I have figured out how to perform some steps, but there are a few I am struggling with.

For the blockwise gabor filtering, can someone provide me an example or the parameters I should use? (All the images I am using are size 388x374)

Before filtering the images and creating the skeleton map, I would like to somehow normalize the images. Ideally I would like to center each thumbprint based on some reference point. It seems like creating an orientation map may be how to accomplish this step. If so, can someone provide so example/help to obtain the orientation map? Once i I have obtained the orientation map how can I use it to find a reference point?

Thank you for your help

Thumbprint Gabor Filtering, Orientation Map and Normalization

Hi everyone,

I have been working through the steps of fingerprint matching presented in an answer here: http://answers.opencv.org/question/6364/fingerprint-matching-in-mobile-devices-android-platform/

Some of the links provided in the answer are now dead and I cannot find examples online. I have figured out how to perform some steps, but there are a few I am struggling with.

For the blockwise gabor filtering, can someone provide me an example or the parameters I should use? (All the images I am using are size 388x374)

Before filtering the images and creating the skeleton map, I would like to somehow normalize the images. Ideally I would like to center EDIT:

I have begun working on this again and made some progress. I have obtained the orientation map. I think there should be some way to improve my results though, as they don't seem as good as the result in the referenced answer.

Currently, I am obtaining the gradient direction for each thumbprint based on some reference point. It seems like creating an orientation map may be how to accomplish pixel. Then I split the image into non-overlapping windows. I average the directions within the window to find the local direction for that window and plot a corresponding line.

Is there some improvement I can make to this step. If so, can someone provide so example/help to obtain the orientation map? Once I have obtained the orientation map how can I use it to find a reference point?

Thank you for your helpprocess to better my results? Is this the correct way to get "block-wise gradient direction" as the referenced answer states?

image description

image description

Thumbprint Gabor Filtering, Orientation Map and Normalization

Hi everyone,

I have been working through the steps of fingerprint matching presented in an answer here: http://answers.opencv.org/question/6364/fingerprint-matching-in-mobile-devices-android-platform/

Some of the links provided in the answer are now dead and I cannot find examples online. I have figured out how to perform some steps, but there are a few I am struggling with.

For the blockwise gabor filtering, can someone provide me an example or the parameters I should use? (All the images I am using are size 388x374)

EDIT:

I have begun working on this again and made some progress. I have obtained the orientation map. I think there should be some way to improve my results though, as they don't seem as good as the result in the referenced answer.

Currently, I first perform CLAHE to increase image contrast. Then, I am obtaining the gradient magnitude and direction for each pixel. Then Next, I split the image into non-overlapping windows. I average the directions within the each window to find the local direction for that window the windows and plot a corresponding line. lines.

Is there some improvement I can make to this process to better my results? Is this the correct way to get "block-wise gradient direction" as the referenced answer states?

image description

image descriptionimage description

Thumbprint Gabor Filtering, Orientation Map and Normalization

Hi everyone,

I have been working through the steps of fingerprint matching presented in an answer here: http://answers.opencv.org/question/6364/fingerprint-matching-in-mobile-devices-android-platform/

Some of the links provided in the answer are now dead and I cannot find examples online. I have figured out how to perform some steps, but there are a few I am struggling with.

For the blockwise gabor filtering, can someone provide me an example or the parameters I should use? (All the images I am using are size 388x374)

EDIT:

I have begun working on this again and made some progress. I have obtained the orientation map. I think there should be some way to improve my results though, as they don't seem as good as the result in the referenced answer.

Currently, I first perform CLAHE to increase image contrast. Then, I am obtaining the gradient magnitude and direction for each pixel. Next, I split the image into non-overlapping windows. I average the directions within each window to find the local direction for the windows and plot a corresponding lines.

Is there some improvement I can make to this process to better my results? Is this the correct way to get "block-wise gradient direction" as the referenced answer states?

My next step will be to enhance the image using block-wise gabor filters. Should they be applied to each window using the window's average direction I found? I am not sure what exactly the answer means here: "Enhance the normalize image by block-wise gabor filter according to block-wise orientation map then binarize the fingerprint"

image description

Thumbprint Gabor Filtering, Orientation Map and Normalization

Hi everyone,

I have been working through the steps of fingerprint matching presented in an answer here: http://answers.opencv.org/question/6364/fingerprint-matching-in-mobile-devices-android-platform/

Some of the links provided in the answer are now dead and I cannot find examples online. I have figured out how to perform some steps, but there are a few I am struggling with.

For the blockwise gabor filtering, can someone provide me an example or the parameters I should use? (All the images I am using are size 388x374)

EDIT:

I have begun working on this again and made some progress. I have obtained the orientation map. I think there should be some way to improve my results though, as they don't seem as good as the result in the referenced answer.

Currently, I first perform CLAHE to increase image contrast. Then, I am obtaining the gradient magnitude and direction for each pixel. Next, I split the image into non-overlapping windows. I average the directions within each window to find the local direction for the windows and plot a corresponding lines. Is there some improvement I can make to this process to better my results? Is this the correct way to get "block-wise gradient direction" as the referenced answer states?

My next step will be to enhance the image using block-wise gabor filters. Should they be applied to each window using the window's average direction I found? I am not sure what exactly the answer means here: Can anyone further explain the answer's step: "Enhance the normalize image by block-wise gabor filter according to block-wise orientation map then binarize the fingerprint"

Any tips will be very appreciated!

image description