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Hi Everyone,
Can you give me a solution about how to export high quality figures from MATLAB Simulink for inserting in MS Word. The generated circuit line in Simulink needs to be clear and bold that preferable for publication. After Drawing the circuit by default setting seems lines are very thin after COPY.
Looking forward to hearing from you.
Thanks
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ModelName % to open the model
print('-sModelName','-dpng','model.png')
This is a way to save ModelName.mdl in png format. Image name will be modemodel.png
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The image quality should be measured perceptually. In addition, the objective image quality assessment (IQA) measures are used. Why?
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Dear Hafijur Rahman, the trouble with human visual perception is that not all humans in fact have the same perception, which makes it hard to objectively quantify image quality. And we do need such objective technical comparison tools. Nevertheless, measurement tools for this purpose should be designed in such a way that they indeed match withe the average human observer. Even something relatively simple as the V-lambda curve that CIE defined to model the spectral sensitivity of the average adult human eye, does not match with all individual spectral sensitivities. Yet, this curve helps us to build comparable lux meters and design predictable lighting installations.
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Dear all
I was wondering if someone knows how to infer the results of a BRISQUE or NIQE score for a particular image.
For example, in CIELAB color difference, a Delta E less than 2 is considered to be imperceptible.
Do we have similar or related perceptual inferences for BRISQUE and NIQE scores as well?
I understand that a lower score is better but I am looking for the perceptual impact of these scores.
For example, what is the impact of 1 unit NIQE score or 10 units of BRISQUE score?
I am testing images of a same scene taken with two different cameras to test their image quality.
I would appreciate if you could provide some references for the same.
Thanks in advance
Aiman
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Both BRISQUE and NIQE are two well-known No-reference image quality measures in practice. You may note that No-reference image quality measures are different from reference-based image quality measures such as PSNR and SSIM, where we have the original image and another version of the image (may be degraded version).
Now, I will try to come o your question, the BRISQUE score from an image will be a positive value ranges from 0 to 100. A low BRISQUE measure indicates that the image is having high quality.
While considering NIQE measure also a smaller score indicates better perceptual quality. The range of possible NIQE measures are not defined.
If you have some experience in Matlab, you can try these two functions
S1=niqe(A);
S2=brisque(A);
then add some noise or apply filtering on the image A then check the same measures. You may get high values as compared the measures from the original image.
I hope the above-mentioned discussion will help you.
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I am currently developing a mammography phantom that has an MTF edge portion. The MTF portion is used to test the resolution of the digital mammography unit. My MTF is made of stainless steel with a thickness of 0.8mm and a dimension of 40mm x 40mm.
After exposing the phantom, I have an image of the MTF (a square object with very high attenuation compared to the background). I don't know what the next step is, analyze it or determine the MTF from that image. I just know that you need to put the ROI between the edge and the background. Is there a way I can manually determine the MTF edge of the system? Can you provide me an article or steps on how to do so. Or do I really need software to do determine the MTF? What software can I use to determine the MTF edge? Can you suggest software and the steps on how to determine the MTF from that software.
My alternative way of measuring the MTF of the system is to use a high attenuating material and bar pattern materials. So this MTF is made of a copper sheet (0.2-mm thick), a copper wire that forms 2lp/mm and 4lp/mm, and a transparent area (PMMA). I got this from IEC, and the method of determining the MTF is easy. But this kind of configuration is not used in any commercialized mammography phantom. Most commercialized mammography phantoms used MTF edge. That's why I prefer the 1st MTF configuration.
Do you know the difference between MTF edge and MTF bar pattern?
I really appreciate any help you can provide. Thank you!
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Dear Neil
To calcultad the MTF from edges or slits method you can use some available free softwares. I suggest the following:
(PDF) Free software for performing physical analysis of systems for digital radiography and mammography (DOI: 10.1118/1.4870955)
Best, Alessandra
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How to evaluate the quality of an enhanced underwater image, where the ground-truth image is not available?
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Many parameters can be used such as; Peak Signal-to-Noise Ratio (PSNR), Root Mean Squire Error (RMSE), Standard Deviation (SD), smoothness, entropy, Structural Similarity (SSIM) can be found in
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The image quality assessment is categorized into full reference (FR), reduced reference (RR), and No-reference (NR). In FR method, the reference image needs to available to be compared to distorted image.
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Don't think these are using SIFT features, but a number of python and matlab based implementation available in GIthub.
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Hi.
Can a loose metalic object, from a patients pants or so, affect the homogeneity of the magnetic field? And affect the quality of the image, if it's stuck to the scanner while scanning?
Thank you :)
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2 possible effects:
1. disruption of magnetic field homogeneity and/or gradient linearity, leading to spatial distortion and/or rf inhomogeneity.  Magnitude of effect depends upon size, location and magnetic susceptibility of metal.
2. arcing (sparking) caused by metal rubbing against housing, caused by vibrations during scanning.  This will cause various noise patterns in the image, depending upon when the arcing occurred during the data acquisition (K space filling). Even non magnetic metal can cause this.
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I want to measure strain in my sample by comparing their IQ map with undeformed sample's IQ map in aramis software,but need help about how to do this offline.
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We (colleagues of mine)  used simple images collected by a camera. No EBSD maps! Unfortunately they gave it up several years ago. 
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I am hiding 1 bit by using the LSB.
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Image quality assessment metrics suggested by previous contributors are MSE and PSNR. These metrics are simple to calculate,mathematically convenient, and have clear physical meanings.  However these IQ assessments lack two critical features: 1) Ability to image similarity across stego image of varying distortion types; 2.) They are not very well matched to perceived visual quality. A new approach to assess image quality independent of the type and size of pixel size of concerned stego images is the estimation of Structural Similarity indices using  Structural Similarity Index metric(SSIM)
The author might need to see our investigation of SSIM computation of dissimilar stego images in secure e-voting application in this link:
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  1. I want to calculate colorfulness of any given image. I used CIELab colors space to calculate colorfulness.
  2. What would be the value of colorfulness if I would try it on an original image (no change in image is done).
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Hi you can go through Ohta, N., Robertson, A.R., 2005. Colorimetry: fundamentals and applications. Wiley-IS&T series in imaging science and technology
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After getting RGB images from a hyperspectral image using 5 different techniques, how can one represent the quality of results quantitatively? A quick and handy solution is required.  
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Such methods exist, but they have different accuracy and may not reflect the various features of human vision. By the way, check Matlab Central.