## Integration using 2 images of Slopes

Started by in comp.dsp13 years ago 2 replies

Hi everybody! I don't know if my topics is really clear... In fact, lets say that 'I' is an image. I have the image of 'dI/dX' and...

Hi everybody! I don't know if my topics is really clear... In fact, lets say that 'I' is an image. I have the image of 'dI/dX' and 'dI/dY'. Is it possible to get the image 'I' from those slopes (using MATLAB)? I didn't find any topics related to this, hope I didn't miss it.

## Are these two methods identical to get the noise only image

Started by in comp.dsp8 years ago 2 replies

Under the same circumstances, I get 15 X ray images I1, I2, I3, ?,I15. Then two methods were used to get the noise only image. First...

Under the same circumstances, I get 15 X ray images I1, I2, I3, ?,I15. Then two methods were used to get the noise only image. First method: Noise image=(I1-I2)/sqrt(2). They said that subvided by sqrt(2) can maintain the variance of the Noise image identical to I1 and I2. Second method: Noise image=I1-(I1+I2+I3+?+I15)/15. Can this method maintain the variance of noise image identi

## Sub sampling in frequency domain

Started by in comp.dsp11 years ago 1 reply

Hi, I like to know the procedure to subsample an image in frequency domain For example Image = ...

Hi, I like to know the procedure to subsample an image in frequency domain For example Image = 121 122 131 141 123 132 141 152 101 97 191 120 100 41 40 78 Sub sampled image is average of 2X2 sub matrix without overlap Result ------------ Sub ...

## algorithms for star field compression

Started by in comp.dsp7 years ago 13 replies

Dear all, I am working on the software of a Star Tracker device which should be capable to compress the images for transmission [1]. The CCD...

Dear all, I am working on the software of a Star Tracker device which should be capable to compress the images for transmission [1]. The CCD is 512x512 and each pixel is digitized with a 12bit ADC and the image frequency is ~10Hz. Since the bandwidth available is rather limited (~1.5 Kb/s) I need to compress the image to a level of few bytes per image to be able to cope with the input...

## Neural Network for Image Processing

Started by in comp.dsp10 years ago 1 reply

Hey, I have an Image of 512 * 512 and need to train a neural network to learn this image so as to use it in detection of bad spare parts....

Hey, I have an Image of 512 * 512 and need to train a neural network to learn this image so as to use it in detection of bad spare parts. Whenever i feed this to ANN toolbox, it is saying memory overflow. How do i do this ? Do i need to do it in window like ? How do i generate my target data for each of the windows? Any form of help will be appreciated.

## Reviewer need for an IEEE 2-D image processing paper

Started by in comp.dsp5 years ago 2 replies

Hi Guys, One of the professors working with the IEEE Image Processing Society recently asked me to review a manuscript of an image...

Hi Guys, One of the professors working with the IEEE Image Processing Society recently asked me to review a manuscript of an image processing paper being considered for publication. After telling the professor that I wasn't qualified to review image processing papers he asked if I knew anyone who was qualified. I couldn't think of anyone but I told the professor that I would...

## Interpolation of versions of an image at different resolutions

Started by in comp.dsp12 years ago 6 replies

Here's a little something I'd like to get suggestions for so I can try them. My problem is the following, for an original image of...

Here's a little something I'd like to get suggestions for so I can try them. My problem is the following, for an original image of given dimensions, you're only given (for example) 6 lower resolution images and by combining them try to obtain something as close as possible to the original full resolution image. Here are in my example the characteristics of the 6 low resolution images : 1st...

## Image Processing to transform background

Started by in comp.dsp15 years ago 4 replies

What is a good image algorithm that will convert a background of one color to another? One that will handle edge effects on the border between...

What is a good image algorithm that will convert a background of one color to another? One that will handle edge effects on the border between the background and the rest of the image? -- % Randy Yates % "With time with what you've learned, %% Fuquay-Varina, NC % they'll kiss the ground you walk %%% 919-577-9882 % upon." %%%%

## Gibbs phenomenon

Started by in comp.dsp12 years ago 10 replies

Hi! I am working over high quality image processing algorithms (image shifts, image rotation, etc). I am trying to use 1D sinc interpolation,...

Hi! I am working over high quality image processing algorithms (image shifts, image rotation, etc). I am trying to use 1D sinc interpolation, but it produces Gibbs artifacts. Is it possible to modify sinc interpolation in some way in order to reduce these artidacts? Perhaps, it is better to use some other interpolations for the case of sharp edges? I have tried to apply some windows (Hann, La...

## a question about image filtering: what should be the scaling factor after image filtering?

Started by in comp.dsp14 years ago 1 reply

Hi all, I am facing a headache question in image filtering... I want to apply a low pass filter to an RGB image... I used Gaussian filter,...

Hi all, I am facing a headache question in image filtering... I want to apply a low pass filter to an RGB image... I used Gaussian filter, using Matlab "fspecial" command h=fspecial('gaussian', [31, 31], 5); ... and I am setting the cutoff frequency quite low because I really want to blur the images quite heavily... I applied the filter to each of the RGB planes, using the Matla...

## tiny image filter with large filter

Started by in comp.dsp14 years ago 1 reply

HI all, I am have a tiny image filtering with my 2D Gaussian filter. The Gaussian filter is 20 times larger than the tiny input image in both...

HI all, I am have a tiny image filtering with my 2D Gaussian filter. The Gaussian filter is 20 times larger than the tiny input image in both X and Y size. Are there any methods to speed up my convolution? Since I just want the same size output as my tiny input image size; can I truncate the Gaussian filter to be the same size as the tiny input to make the filter and the image the s...

## Polyphase interpolation on an image with real value only

Started by in comp.dsp15 years ago 2 replies

Hi all, I encounter some "problem" while using polyphase filter for interpolation. I have implemented a 8 zero crossing with upsampling of...

Hi all, I encounter some "problem" while using polyphase filter for interpolation. I have implemented a 8 zero crossing with upsampling of L=32. The image I used are a simulated image with 4 sinc impulse response near the four corner. All pixels values are positive. While performing interpolation, such as for rotation operation, I found that some of the values return is negative? ...

## FFT in Matlab

Started by in comp.dsp14 years ago 1 reply

Hi, I created an image in Matlab in the following way: I created 2 vectors that represent the image coordinates, and gave a value to...

Hi, I created an image in Matlab in the following way: I created 2 vectors that represent the image coordinates, and gave a value to each combination of the vectors. For example: a=[-0.4:0.02:0.4], b=a, image(y,x) is the value of a(y), b(x). Then I performed some operations that are like Fourier transform. I got new coordinates that were not equally spaced. So I made a grid, and interpolat...

## How is this related to image processing?

Started by in comp.dsp13 years ago 1 reply

Hi, I need to identify or find if a particular pattern( Actually it is hyperbola pattern) is present in an image. Infact, the shape of...

Hi, I need to identify or find if a particular pattern( Actually it is hyperbola pattern) is present in an image. Infact, the shape of the hyperbola can again vary as different shapes and sizes. What part of image processing is this related. Can anybody point me to certain topics and resources which will help me do this? Bye

## image

Started by in comp.dsp3 years ago

hiiiiiiiiiiiiiiiiiiii i want to know the matlab code for image segmetation using genetic algorithm???????????????????????? plzzz help

hiiiiiiiiiiiiiiiiiiii i want to know the matlab code for image segmetation using genetic algorithm???????????????????????? plzzz help

## FFT in Matlab

Started by in comp.dsp14 years ago 1 reply

Hi, Thanks, but it is not an fftshift problem. The image I get is just a shrinking of the original image.

Hi, Thanks, but it is not an fftshift problem. The image I get is just a shrinking of the original image.

## Image Processing Algo on Processor

Started by in comp.dsp15 years ago 8 replies

Hi All, I am working on image compression algo,which needs to be finally processor based.i need some suggestion regarding the time taken...

Hi All, I am working on image compression algo,which needs to be finally processor based.i need some suggestion regarding the time taken to code,test the an image processsing algo in a standard DSP processor such as TI's or in Xilinx FPGA.which one would be better???in terms of time taken and performance..??? cheers MIA

## Saving a matlab plot as an image help

Started by in comp.dsp9 years ago

Hi everyone, I have a matlab related quetion which can seem simple but it's taking me ages. I am plotting an x and o over an image and I...

Hi everyone, I have a matlab related quetion which can seem simple but it's taking me ages. I am plotting an x and o over an image and I want to save that image whith the same size as the original one. This is what I mean: figure, imshow('data0002.tif'), hold on, figure,plot(Z{2}(1,:),Z{2}(2,:),'rx',hat_X{2}(1,:),hat_X{2}(3,:),'co') With this command I manage to do that, the proble...

## Text Extraction from image

Started by in comp.dsp10 years ago 1 reply

Hi iam doing my M.Phil and my research area is Image Processing and specifically "TEXT EXTRACTION FROM IMAGES".. Can u give me some ideas...

Hi iam doing my M.Phil and my research area is Image Processing and specifically "TEXT EXTRACTION FROM IMAGES".. Can u give me some ideas based on this.. from the papers already i gone through i can able to understand only the THEROTICAL Concepts.. I dont know to apply PRACTICALLY eg.. After detecting text in an image put bounding boxes but my big doubt is how to put bound...

## Idea exploration - Image stabilization by means of software.

Started by in comp.dsp14 years ago 27 replies

Basically let the camera take it's picture though user's hand is shaky, and use a mechanism to record down the angle of user's handshake in...

Basically let the camera take it's picture though user's hand is shaky, and use a mechanism to record down the angle of user's handshake in steps of 1us, now I get V = [v0, v1, ...v(n-1)]; With this vector, I calculate displacement vector the image has moved in terms of number of pixels P. Assume the image sensor's voltage rises linearly w.r.t exposure time (or any charactized waveform). ...