Questions tagged [image-processing]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
2
votes
3answers
51 views

How to paint onto 3d models

I have searched this topic for very long time and have found basically no information on it. If we have a 3d model with a uv layout. What is the basic technique for 3d painting on said model with a ...
0
votes
3answers
91 views

How to remove background text from an image file

I have this image below, I want to get rid of the text 'MSAR IDs' that is in the background. I am extracting the numbers from the image with OCR, the numbers that have a white background get extracted ...
1
vote
1answer
114 views

How to translate the center of an equirectangular projection?

I'm trying to perfectly align two or more equirectangular photos of the same place taken from slightly different positions. Using an example provided by openMVG I managed to get the relative position ...
0
votes
0answers
28 views

Do scanners and scanning software compensate and enhance blurry sources?

I received a pdf from a client containing several invoices. Upon further inspecting, some lines on the invoice seem digitally produced. When I tried selecting the page, copying it then pasting it on ...
0
votes
0answers
22 views

Implementing Feather feature of Photoshop

The "feather" in photo & video editing softwares like photoshop & Premiere Pro, I need to know whether it is simply a Gaussian blur around the edges of boundary or it is something ...
0
votes
0answers
32 views

Are there algorithms besides Canny edge detection that can create consistent width edges?

Sobel edge detection is pretty much the quintessential way to get edges out of an image. It however suffers from certain quirks. One example is, because it's gradient, based certain surfaces exhibit ...
2
votes
1answer
37 views

Interpreting Image Processing Math Equation

I am reading "Image Processing and Analysis" by Chan and Shen, c 2005 SIAM. They introduce some notation I'm not 100% sure how to interpret: $$ u_0(x)=u(x)+n(x), x=(x_1,x_2) \in \Omega $$ They ...
1
vote
1answer
64 views

Estimating the position of vertexes in a 3D model

Introduction to my project: We are machine learning scientists and working on a biomedical system for tracking tongue for speech pathology using a technology called EMA (Electromagnetic ...
1
vote
0answers
46 views

What modern C++ Unit Testing Framework do you use for highly parallel image, 3D and higher dimensional matrix processing workloads? [closed]

Most of the existing open-source libraries such as OpenCV, Tensorflow, and Pytorch use Google Test. I would like to know about strong alternative testing frameworks that thrive under a similar ...
1
vote
0answers
31 views

HSI color space and RGB color space relationship in Steganography

I need to embed text in an image, research papers say HSI produces better mse and psnr therefore are better for steganography. I have RGB values(69,223,90) and its corresponding HSI is (127.223,0.458 ,...
0
votes
0answers
18 views

How Quantum works exactly in MagickCore?

It's been long I have been trying but I guess I will give up now, I am not able to understand some stuffs + documentations seem wrong. For example, In Magick++, the QuantumRange equations they ...
0
votes
0answers
23 views

What technique should I use to animate a summer picture to its winter version: linear interpolation, or opacity?

I've used a CycleGAN to generate the winter version from a summer picture (https://github.com/junyanz/pytorch-CycleGAN-and-pix2pix). An example of the output can be seen in the top right corner: ...
0
votes
0answers
44 views

How to filter a photo to look like a cartoon / anime?

I am interested in reverse engineering a video effect, that is composed of different parts. I'll try to split it into different questions as advised on StackExchange Meta. Part 1: TV-Noise effect ...
0
votes
0answers
15 views

Create a TV noise effect

I am interested in reverse engineering a video effect, that is composed of different parts. I'll try to split it into different questions as advised on StackExchange Meta. This is the example image: ...
0
votes
0answers
45 views

What fast algorithms can generate not-realistic but quite handsome animated landscapes?

I was looking for algorithms that quickly compute quite nice realistic, or not realistic, animated landscapes, in video format ("animated" = the camera moves, or the water is animated, etc.) But all I ...
0
votes
0answers
31 views

Is it possible to develop this image generator from randomly redrawn detected edges or am I going straight to the wall?

Aim I would want to procedurally generate totally new images from a set of thousands of images of a given category (simple landscapes for example). Deep-learning won't be used for this purpose. This ...
1
vote
1answer
53 views

Given a background image B and a composie image of A OVER B, can we somehow recover image A?

I often find myself in the situation where I have some old image where I composed a translucent overlay on top of a background, but then lost (or more likely discarded) the overlay. I still have pre-...
9
votes
3answers
1k views

What's a proper way to clamp dither noise?

When reducing color depth and dithering with a 2 bit noise (with n=]0.5,1.5[ and output=floor(input*(2^bits-1) + n)), the ends of the value range (inputs 0.0 and 1.0) are noisy. It would be desirable ...
1
vote
0answers
84 views

Visualize the variance of an image

Let $h_j$ denote the image reconstruction filter of pixel $j$. I'm estimating the color value $$I_j=\int h_jf\:{\rm d}\mu$$ of the $j$th pixel (see [Veach, Section 8.2]) by an asymptotically ...
2
votes
1answer
37 views

Controlling “zoom” and “position” of a cubemap in shaders

I am trying to mimic reflections in image composition using shaders. I have gotten this far: In this image the floor is "reflecting" the back wall, however the reflection is uncanny because the ...
3
votes
0answers
77 views

Upscaling screenshots with subpixel rendered text

Upscaling a screenshot with subpixel antialiased text produces unpleasant color fringes, e.g. why does black text have orange and blue pixels This is especially annoying when trying to show an ...
1
vote
0answers
31 views

Extract object from image and apply it to different image

SHORT BACKGROUND: I am developing a neural network based model to differentiate benign and malignant ovarian tumors. I am working with transvaginal ultrasound images, some of which contains yellow ...
0
votes
0answers
24 views

What's the most efficient way to extract the information from Shipping Labels?

I'm currently using Google Cloud Vision API to extract shipping information from shipping labels. While, OCR accuracy is not the issue here, the problem is that the data extracted from the label is ...
0
votes
0answers
22 views

GIMP's Additional blending formula

I try to implement GIMP's the Additional blending mode for layers in my application. I've found the formula: E = min((M+I), 255) I think, that if I blend ...
0
votes
0answers
22 views

Convolution of multiple gaussian filters with different sizes

What is the size of the final filter after implement convolution of multiple gaussian filters with different sizes?
1
vote
1answer
61 views

Extracting information from EXR Files

I am relatively new to computer vision and image processing. I have a single EXR file with 7 channels: 1-3 give me the RGB values, 4-6 give me the surface normals coded as RGB values and 7th channel ...
1
vote
1answer
52 views

What kind of denoising must follow locally adaptive binarization?

I am experimenting with local (adaptive) grey threshold for the binarization of B&W photographs of yellowed manuscripts: I got adaptive thresholding working in both scikit-image and cv2. In both ...
1
vote
1answer
70 views

How do you add text dynamically to an image and export it?

Apologize for crossposting, but I posted this in Stack Overflow and thought it might be a better post here. Recently, Spotify released their 2019 Spotify wrapped web application, which is essentially ...
0
votes
1answer
66 views

How RGB images are formed when normalized between 0 and 1

There is a popular technique of normalising images by dividing each pixel with 255 so that it comes in the range of 0 and 1. But, then how the same colours are formed when we normalize images. for ...
3
votes
2answers
234 views

What does texture resolve mean?

In the context of render targets or textures, what does "resolve" mean? For example: To resolve a color texture. From my understanding, it seems to mean, "copy but process/convert at the same time", ...
0
votes
2answers
77 views

Is there way for polygon decomposition by thickness?

Here is an example dots representing coordinates of pixels added more representative example added real example added main problem
1
vote
0answers
31 views

Fuse 3D-Points in Bundle Adjustment? [closed]

(Crossposting from here: https://softwareengineering.stackexchange.com/questions/399331/fuse-3d-points-in-bundel-adjustment) I'm actually implementing my own Pose-Estimation/- and -Refinement ...
1
vote
1answer
96 views

Artificially increase the region of interest of an image

I am solving an image segmentation problem. To increase the accuracy of the model, I came across the following preprocessing step- First, the set of pixels of the exterior border of the ROI is de- ...
1
vote
1answer
31 views

How to create static alpha masks of an image

I have an image of following type- I want to create mask of the following type where the inside area is white and rest of it is black. How to do it?
1
vote
3answers
252 views

Blurring image with RGB values without convolving it with a kernel

I'm using an app for face redaction that doesn't allow access to the source code but only allows me to pass pixel values for red, green and blue channel upon which it creates a matrix with the same ...
0
votes
2answers
98 views

How RGB images are formed

I have a noob level question about RGB images- Pixels in RGB images are in the range of (0-255), so technically each channel ranges from 0(black) to 1(white), then why we say that each image has a Red,...
0
votes
1answer
91 views

Want to study computer graphics

I want to study computer graphics but I don't have a strong foundation in mathematics. I am doing a computer science degree that doesn't cover computer vision, image processing or computer graphics, ...
1
vote
0answers
30 views

Deskewing and Cropping Scans using ImageMagick

Attempting to deskew and crop scans of a CD booklet using ImageMagick. Here's one image which I've been using as an example on which to build my one-liner - https://mega.nz/#!jIQD3aqC!PbjG4_Xaq-...
2
votes
1answer
205 views

Downscaling texture via mipmap [DirectX 11]

I am implementing a post-processing effect in my DirectX 11 pet renderer. The post-processing pass is implemented by rendering a full-screen quad covered with texture containing original rendered ...
3
votes
0answers
73 views

How to separate, modulate, and reassemble spatial frequencies?

Background I am trying to create a node in Blender that would allow me to do what you would do with an audio equalizer but on the spatial frequencies of an image: A sort of panel with eight ...
4
votes
2answers
682 views

reducing image size increases file size?

When I download this image: (source: ucn.edu.ni) then its total size is 341,0 kB. The image has a width of 2880 pixels and height of 1100 pixel and 1 X/Y resolution pixel/in. I opened the image ...
6
votes
2answers
392 views

Was Evans & Sutherland CT5 really created in 1981?

A few days ago I found a video on Twitter showing the Evans & Sutherland CT5 Flight Simulator system. It was labeled as 1981 footage and looked really amazing. The first time I saw similar 3D ...
3
votes
1answer
86 views

Origin of blurring and colour distortion in monochrome diagrams

I am analysing a large number of PDF files from scientific articles, all of which contain images which (I think) were originally monochrome ( black/white). The images have been extracted with Apache ...
0
votes
1answer
43 views

How to make the lines of a (binary) image dotted or dashed?

Let's say I had a binary image (i.e. only contains black and white pixels). For example, this one: How would I make all the lines in this image dotted or dashed? In other words, the eyes would be ...
2
votes
0answers
60 views

How to project an image on spherical surface with least possible distortion

I did not know where to ask, I will try it here. I work in a local planetarium and I wonder if it is possible to edit an image in such way, that when projected on spherical cupola (diameter 8 m), it ...
1
vote
0answers
31 views

Are there some methods of preventing tools like FotoForensics from detecting manipulations?

I am asking this question purely our of curiosity. I do not look for step-by-step tutorial on how to manipulate a photo and making sure that it will be hard to detect it. I was wondering, because ...
0
votes
0answers
310 views

Lanczos filter implementation issue

I tried to follow Nathan Reed post Antialiasing: To Splat Or Not to implement splat method. The image I am getting thorugh the Lanczos filter is very different than Nathan. I do not understand where ...
1
vote
1answer
780 views

Convert RGB image to YUV420 using a hlsl shader

I am new to shaders and I need to convert efficiently an RGB image to YUV420. I can convert the RGB image to YUV420 with a simple c++ program that uses the ...
3
votes
1answer
114 views

Tiled Image Palettization Algorithm?

In most cases today, image palettization consists of reducing the overall number of colors in an image to some fixed number globally. This is typically solved as a straightforward but computationally ...
2
votes
2answers
2k views

Passing parameters in Metal Compute Kernel using Swift 4

On the CPU side, I have a structure I want to pass to the compute kernel: ...