how can i obtain a clear image from a set of 180 images

I have a series of images produced by an ultrasound machine. The images are of an eraser. the position of the eraser is in a different as the ultrasound probe moves. I did image registration to register all of the images in respect to frame 1 (I have a total of 180 images). the intensities of the pixels of the eraser are not consistent between the frames. I took the average of the 180 images and the output image was blurred. I was wondering if u can suggest away to me so that I can get a clearer image out of the 180 images other than averaging them. Thank you in advance

[Walter Roberson]

(Sample images can be seen at http://www.mathworks.co.uk/matlabcentral/answers/105504-remove-out-of-place-pixel-values )

Answer 1

[Image Analyst]

See section 20.12 here for algorithms: http://iris.usc.edu/Vision-Notes/bibliography/contentsmedical.html#Medical%20Applications,%20CAT,%20MRI,%20Ultrasound,%20Heart%20Models,%20Brain%20Models. Pick on, code it up, and come back here if you have questions.

[Yazan Awwad]

I looked at those algorithms but those are used to remove speckle noise using filters. What i am looking for is to get one output from the 180 images and not clear each of the 180 images

[Walter Roberson]

20.7.1.2 leads to something that is not for speckle noise, it appears to me.

[Image Analyst]

Does the scene move between frames? If not, I don't see why averaging frames would produce blur. If they do move, reduce noise on each frame, then call imregister() to align them all, then do averaging.

[Yazan Awwad]

The eraser is what moves, but using phase correlation I aligned all the images (see examples at this link: http://www.mathworks.co.uk/matlabcentral/answers/105504-remove-out-of-place-pixel-values ). After i averaged them all, the output image was blurred. Is it may be because i am doing the registration incorrectly. Can u plz take a look at the sample images and probably let me know what is going wrong? Thank you