Photography Stack Exchange
Photography Stack Exchange

Questions tagged [image-processing]

Image processing is the computational transformation of an image signal. It's about the technical side of batch transformations, conversions, and enhancements, as distinct from post-processing (adjusting an image to achieve a desired look, probably using image processing).

256 questions
6
votes
5 answers

Object size discrepancy in image (Round object occupies more pixels than it should)

I am photographing a sphere (a ball): in the same picture I have also placed a ruler. The ball and the ruler are in the same plane. i.e. the ruler is placed such that it is aligned with the center of the ball. I try to predict the size of the image…
user4749
  • 159
  • 3
4
votes
2 answers

Which colour space should I apply Image sharpening filter?

I am trying to apply a Image sharpening 2D filter kernel(Laplacian) on a Image in my proprietary Image/Video processing pipeline(From Camera raw to final JPEG/MPEG). I plan to perform 2D convolution of this Laplacian kernel with the 2D image array…
goldenmean
  • 1,219
  • 1
  • 14
  • 25
2
votes
3 answers

How to do automated image analysis of astronomical photographs?

I have many pictures like the following: As many of you may recognise, this is a picture of Jupiter and its four Galilean moons. Using these images, I am aiming to calculate the mass of Jupiter by finding the orbital distance and orbital period of…
StopReadingThisUsername
  • 121
  • 2
2
votes
1 answer

How do I convert a single spherical distorted image to a rectangular image?

How can I convert a single spherical distorted image to a rectangular image?
Fadi Alsafi
  • 21
  • 2
1
vote
1 answer

How does the scale of a CCD work and what does the function of gamma do to this scale?

I am using a fluorescent microscope with a CCD attached so that I can take images. What I'm wondering is how the scale between the pixel values works? is it different for different CCDs?
Dametre Thunberg
  • 13
  • 2
1
vote
3 answers

Utilities for comparing different JPEG compression engines?

I'm looking to do some statistical analysis on the effect on an image of various compression systems, with the end-goal of hopefully being able to determine which is a recompressed version of which. To do this, I need to be able to feed a set of…
Fake Name
  • 3,340
  • 20
  • 22
1
vote
2 answers

Flat fielding an image with two 1-D arrays

This is more of a math questions, but I thought I had a better chance of finding a camera enthusiast with a math background here. I've always flat fielded images using a two dimensional array with a gain for each pixel. Therefore I end up with a…
Peter
  • 155
  • 5
1
vote
1 answer

Aligning images with align_image_stack utility

For a school project, I am capturing images from two cameras mounted side by side, one NIR and one RGB. Basically I want to make a simple multispectral camera so I need to align the two images on top of each other. The camera's are closely mounted…
Jake
  • 11
  • 1
1
vote
2 answers

Are there effective and simple methods to emulate pixel shift?

This question is about image-processing methods to emulate the noise reduction and increase in details achieved by cameras with good built-in pixel shift (Sony A7 RIII, Pentax K-1 and others). I am assuming situations where pixel shift works well,…
Come Raczy
  • 139
  • 5
0
votes
2 answers

Get pixel to mm ratio from image

Is is possible to get pixel to mm ration from image exif. I have focal length of camera, image resolution, as well as camera distance from object in image (outside exif). I have distance from origin (X, Y) in meters, and I need to figure out how to…
Danilo Vulović
  • 101
  • 1
0
votes
1 answer

2 Images, same object: tone difference and alignment

I would like to know a software which helps in post-production to calculate the general color/tone difference of 2 images. The images contain the same object, but arn't shot from the same position. One image might be sunny, the other cloudy, so one…
Markus Siebeneicher
  • 103
  • 3
0
votes
3 answers

Which has better accuracy? Average of N small pixels, or one large pixel

Starting point of this question is, for a hyperspectral camera in a satellite, where one is interested in macro level details to see crop health, water pollution issues etc. Is it better to go for lower GSD or higher GSD? Now there are so many…
zephyr0110
  • 109
  • 3
0
votes
3 answers

How to fill with transparent color the empty space created by V360 filter of FFMPEG while converting from flat to equirectangular?

I am using this command to convert to flat a small region of an equirectangular image (BTW: how can I specify how much large the section is?): ffmpeg -hide_banner -i input.png -vf v360=e:flat -y output1.png Extracted section: The I modify the…
jumpjack
  • 272
  • 1
  • 2
  • 9
0
votes
1 answer

Which photography movements do these images fit?

I have to take 3 photos for an assignment that emulate historical and modern photo movements and I took a bunch of photos and I don’t know which photo falls under what movement. Can you help? The movements are: a) Pictorialism b) straight…
user89189
0
votes
3 answers

Can anyone help fix this old black & white photo?

I have this family photo that for as long as I can remember (40+ years) has white through the top half of the photo. I would like to try to correct the photo or get someone to do it for me. Any help would be appreciated.
Kathy Connolly
  • 1