10
votes
Accepted
What is bilateral upsampling?
It seems like you're asking two things. I can't really speak technically about JBU, but I can give an overview of the necessary concepts and bilateral filtering generally. You'll probably need to ...
- 1,950
7
votes
Accepted
Why isn't the clear color visible on the screen between frames?
You're confusing the screen (the physical display) with the framebuffer (the memory which gets read out by the display controller). The framebuffer might get cleared at the start of each frame period, ...
- 6,700
7
votes
Why BMP file format last line of image is first line on file?
Here's a quote from Petzold:
So, in DIBs, the bottom row of the image is the first row of the file,
and the top row of the image is the last row in the file. This is
called a bottom-...
- 171
7
votes
Accepted
Bitmap-images or SVG
Neither of your suggestions is a solution for crisp 2D graphics at all resolutions. SVGs are great and infinitely scalable, but since you don't know where the pixel boundaries will lie in the final ...
- 6,700
7
votes
Accepted
Is there a way to script image creation?
ImageMagick is a set of command-line tools that can do the sort of things you describe. For example, this command line will overlay picture B with a centered copy of picture A, resized to 100 pixels ...
- 24.7k
7
votes
Is there a image-format that support an array per pixel?
OpenEXR might be a good fit. You can have an arbitrary number of channels per pixel and the data types for each channel can be integers.
http://www.openexr.com/
- 171
5
votes
Explanation of a the transparency of an .EXR file
In an EXR, the convention is to store associated alpha, also known as premultiplied. The latter term however doesn't do justice to the nuances of the alpha format as compared to its evil distant ...
- 318
5
votes
Accepted
Depth of Field in Path Tracing: What do I do with the secondary ray?
The missing step
If you already understand how to generate a secondary ray, then you have already grasped the difficult part. All you need to do now is find the colour that this secondary ray results ...
5
votes
Accepted
LWJGL/OpenGL get BufferedImage from texture ID
To make it a more complete example, let's also consider loading a texture from a BufferedImage as well.
First let's assume:
...
- 251
4
votes
Accepted
How linear interpolation works between mipmaps?
It's called trilinear interpolation. You first do a bilinear interpolation of the higher-res texture, then do a bilinear interpolation on the lower-res texture, then interpolate between the 2 results. ...
- 3,401
3
votes
What algorithm to reassemble a broken image?
If the pieces are fairly close to where they were, ICP could be of help (under the assumption that the pieces are planar polygons).
- 315
3
votes
Accepted
What is the typical use case for rendering to an image through imageStore?
I've used imageStore as part of compute shaders doing surface extraction. I've only ever used it in compute shaders, to store the calculated data in a texture to be ...
- 2,372
3
votes
Accepted
How RGB images are formed
Each channel ranges not from black to white, but from off to full intensity. What colour is meant by full intensity is down to convention and the presentation technology.
For example, a given image ...
- 6,700
3
votes
How are the colors for each pixel from a Ray Tracer stored in an Image?
Depends if you are talking about CPU or GPU ray tracer. For CPU you generally simply allocate an array of width * height float4's (i.e. for RGB & alpha) and for GPU you allocate a texture (e.g. ...
- 3,616
3
votes
What is bilateral upsampling?
This probably does not explore the full depth of the term, but the first thing that comes to my mind when I hear "bilateral upsampling" is depth-aware blending of low-resolution images onto high-...
- 882
3
votes
Accepted
How are the colors for each pixel from a Ray Tracer stored in an Image?
It doesn't matter. All that matters is that you can store information per pixel.
In most cases this means allocating a x*y array of ...
- 5,920
3
votes
Accepted
splitting hue & saturating and leaving value behind
Removing hue and saturation ("desaturating") leads to a grayscale image with the same luminance as the original colors, for instance:
(source: my own photo)
It is not possible to remove hue ...
- 24.7k
2
votes
Compression-friendly PNG files
PNG format is lossless format where for compression the image is first "filtered" and this filtered image is then passed to DEFLATE lossless compression algorithm. The purpose of filtering stage is to ...
- 3,616
2
votes
Is there a image-format that support an array per pixel?
Probably .dds. You can store there textures array or 3d texture both can be use as array per pixel.
You can try creating this textures with ...
- 596
2
votes
Accepted
What happens when you display a high resolution image on a low resolution screen?
If you scale an image down to a screen that has a lower resolution than yout image, you have to descide what you do, there is no single way of doing this.
There are many different techniques that ...
- 1,810
2
votes
How to denoise video?
A fairly basic but effective technique is median filtering. For video, you can apply it (spatio)temporally by replacing the value of each pixel in each frame by the median of the values of the pixel (...
- 211
2
votes
How linear interpolation works between mipmaps?
You might find the 1983 paper that introduced this**, i.e. Lance Williams' "Pyramidal Parametrics" informative.
You can ignore the scheme, in Figure 1, he used for the layout of the MIP maps as I ...
- 4,171
2
votes
Accepted
Description of the process involved in displaying digital images
Starting from reading the data from a file to displaying the image on the screen.
As was pointed out in the comments, this is an extremely broad question, and depends on what operating system you're ...
- 213
2
votes
Mixing HSV Channel
I think your answer is a little off. When the saturation is 0, the hue is basically undefined. It has some numerical value, but that value is ignored. Saturation of 0 means achromatic, or uncolored. ...
- 3,401
2
votes
Accepted
Get normalized device coordinate of an image pixel
You can modulus by row length to retrieve the x coordinate (think about the x coordinate "wrapping around" after each line), and division by row length to get the y coordinate (inverting the ...
- 36
2
votes
Accepted
How to change a RGB value using a radiance value?
What you're looking for is called tone mapping, which is the process of mapping from HDR color values generated by a physically based renderer, to LDR color values suitable for display on a screen. It ...
- 24.7k
2
votes
Accepted
Difference between Gray-Level and Gray-Scale?
Grayscale images measure only the intensity of light, like for images that appear black-and white with monochromatic shades of gray.
Gray level refers to the actual level. e.g.: A pixel might be ...
- 400
1
vote
How RGB images are formed
CRT monitors are a thing of the past, but I think they are the best example to describe to you "how the image is formed".
Each pixel on the monitor is actually a group of 3 phosphors. A green phosphor,...
1
vote
How does a GLSL Sampler2D read a Vec2 UV coordinate to determine UV range
It's hard to say without seeing the shader in question. My guess is that every animation frame in the atlas has the same size. This fixed size allows mapping any UV coordinates to the proper animation ...
- 820
1
vote
Accepted
can half of a picture be processed and viewed?
Yes, most formats work this way! For example JPEG can be decoded up to the point where the chunks are available:
Image 1 Scaled version of original JPEG picture at (1 048 198 bytes) and corrupted one ...
- 8,397
Only top scored, non community-wiki answers of a minimum length are eligible