Signal Processing Stack Exchange
Signal Processing Stack Exchange

Questions tagged [enhancement]

16 questions
4
votes
1 answer

Sharpening Using Laplacian Kernel - How to Handle the Output (Specifically Negative Values)?

In order to sharpen an image using Laplacian kernel, it should be convolved with the original image. It is evident that the result might have negative values. I am not sure what to do with these values: Subtract the minimum from laplacian then map…
SOFUser
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4
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1 answer

Automatic Image Enhancement of Images of Scanned Documents (Auto Whitening)

Dropbox have make a blog post about there automatic enhancement method for scanned document image - Fast Document Rectification and Enhancement. I followed the post and they mention a formula to make the enhancement: J(x,y) = gain(x,y)*I(x,y) +…
lafi raed
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3
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4 answers

How to Generate False Color Palette

How to convert grayscale intensity input to something like the following image? It seems that no response (0, black) is converted to dark blue, then it goes through other colors to red. How are these colors derived? Is there any standard…
Libor
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2
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1 answer

1st and 2nd Gaussian derivatives for edge detection

I have a project about edge detection, I made research on internet about filters and read many articles but there is an article talked about using Sobel and Gaussian derivatives then it mentioned "edge" and "ridge" detection successively. I found…
Fahd Jerbi
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1 answer

Enhancement by adaptive wavelet shrinkage denoising

I was wondering does anyone know any programming library or a way that can help me implement this algorithm.
Stefan Radonjic
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vote
1 answer

Licence plate enhancement

Is it possible to enhance the image below and make it more readable? I have tried apply binarization but there is some kind of shadow. So I have tried to convert image to gray scale and then equalization It is better, but still there is a…
Krivers
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vote
1 answer

Enhance image in matlab - exp operation - imageJ software-LPR

I use imageJ software, imageJ has a EXP command (process >math >exp ). original image: output image processed by EXP command in imageJ software: in this link explain how do that ImageJ:…
Karo Amini
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vote
2 answers

Speech Enhancement Libraries

Is there any speech enhancement algorithm library? I need to process a sound to voice recognition, and I want to remove noise from audio source.
Victor
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0
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1 answer

Remove spurious peaks of Hilbert transform

I want to eliminate spurious peaks of Hilbert transform for finding glottal closure in the linear prediction (LP) residual. I have the following 4 steps: Down-sample. Hilbert Transform. Identify Peaks in Hilbert Transform. Consider this hypothesis…
Ali Bodaghi
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2 answers

Comparing a clean, noisy and enhanced signal

I was doing some experiments on analyzing few audio samples and I'm stuck with this. Suppose we have a clean audio signal ($y_{clean}$), a noisy version of it ($y_{noisy}$) and an enhanced version ($y_{enhanced}$), by applying some speech…
Debasish Das
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How to solve this math problem regarding Histogram matching?

Please help solve the problem in the picture. I am confused due to the piecewise nature of the density functions. If it was a simple curved PDF, I would simply integrate over full range and use the single CDF expressions. But, for this piecewise…
fac120
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How to Enhance the height difference of the experimental signal data?

I'm very new to signal processing. Is there any kind of method to enhance the signal of experimental data that I get from the experiment? Especially on the difference of y-axis. Thank you This signal is coming from the surface plasmon resonance…
NexusRay
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What is meant by 'combine the luminance and chrominance '

I am new with image processing. I'm trying to implement a research paper in MATLAB. I didn't understand a sentence. Here it is: The luminance is enhanced by applying the proposed algorithm and it is combined with the chrominance and converted…
Hernan Crespo
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How enhance amplitude of audio signal without distortion?

After FFT I've set to zero some frequencies and I'd like to enhance the amplitude in order to recover the leak. I'd like to do a normalization in order to avoid distortion. I've done in this way but the new signal is between 0 and 1 and so the…
Ausilia
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Improving credit-card-like image scan for OCR

OCR works best for black on white or binary images, where letters have sharp contours, no noise, and solid filling, i.e. they are nothing like this: For the curious it's a part of a document number that is embossed. Applying unsharp mask,…
Rajish
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