Stack Overflow
Stack Overflow

Questions tagged [photogrammetry]

Photogrammetry is the practice of determining the geometric properties of objects from photographic images.

Photogrammetry is the practice of determining the geometric properties of objects from photographic images. Photogrammetry is as old as modern photography and can be dated to the mid-nineteenth century. Photogrammetry uses methods from many disciplines, including optics and projective geometry.

http://en.wikipedia.org/wiki/Photogrammetry

130 questions
1
vote
2 answers

Object Interpolation by Distance in an Image

I'm counting objects in an image. I wish to perform a linear interpolation where I know the pixel sizes of my objects at near and far perspectives and the positions of these two objects in the image. The images at the bottom of the image are larger…
Mark Iliffe
  • 417
  • 5
  • 17
1
vote
0 answers

Block seup Pleiades Satellite Imagery

I want do block setup using Pleiades Satellite Imagery in ERDAS IMAGINE. I need to know full procedure. Any document file or video available?
Smith
  • 11
  • 2
1
vote
3 answers

OpenCV: Detect a black to white gradient in an area

I uploaded an example image for better understanding: http://www.imagebanana.com/view/kaja46ko/test.jpg In the image you can see some scanlines and a marker (the white retangle with the circle in it). I want OpenCV to go along a specified area (in…
Robin
  • 1,322
  • 1
  • 13
  • 23
1
vote
2 answers

Real Area of a picture

I want to know the actual area of the entire area covered by an aerial photograph. _The Photo is 4000x3000 pixels _The Focal Length of the camera is 20mm. _The Picture height is 51 meters. I researched and got the scale of the photo. In this case it…
dany luna
  • 43
  • 3
1
vote
1 answer

Masking a moving object with MATLAB

I am using digital photogrammetry to build a point cloud of a river bank. The photos were taken from a moving raft, and I need to mask the raft and oar from the pictures. I used MATLAB to mask the raft, which was fairly easy, but I haven't been able…
Oregon State Student
  • 11
  • 1
1
vote
1 answer

Calibration about micro photogrammetry

this is my first question in this forum. I'm working about a project for my thesis. I have to calibrate my camera to import intrinsic parameters in photoscan fo reconstructon 3D of the object which measures maximum 0,7 x 0,7 mm. I calibrate the…
Luigi_7
  • 11
  • 1
  • 3
1
vote
0 answers

Calculating 3D coordinates of an Object with a Single Phone Camera

I have a phone camera that’s viewing a planar object. I know the real world measurements of the object. Considering the top left corner of the object as the origin, I calculate the coordinates using the real world measurements. With the object…
VRam
  • 11
  • 1
1
vote
1 answer

simple measure over an image

I need to take a measure (Euclidean distance) over a selected points on an image. In order to make this simpler I broke down all the process in steps: Taking/Loading a photo (with a known pattern in it) Recognizing the pattern to calibrate…
xuandl
  • 183
  • 1
  • 2
  • 14
1
vote
1 answer

3D reconstruction using stereo vison - theory

I am currently reading into the topic of stereo vision, using the book of Hartley&Zimmerman alongside some papers, as I am trying to develop an algorithm capable of creating elevation maps from two images. I am trying to come up with the basic…
Zwähnia
  • 177
  • 2
  • 8
0
votes
0 answers

2D to 3D Model Failure using Structure from Motion (OpenCV Python)

import cv2 import numpy as np import os import pyvista as pv # Input directory containing images input_dir = "C:/Users/Pictures/FYP/Box2" # Get a list of all image file paths in the directory image_paths = [os.path.join(input_dir, f) for f in…
ALVIN
  • 1
0
votes
0 answers

Photogrammetry Problem: Mapping two 3D coordinate systems together with rotations

I am trying to complete a relatively basic photogrammetry project where we are trying to locate 3D points of an object in world coordinates from 2D pictures given the locations of the pictures in world coordinates. The angle of projection of the…
Peterqt
  • 1
  • 1
0
votes
0 answers

Rotate a picture using Homography from top view. I need to find the calibration of the hypothetical camera

I am currently working on an application that allows to make 3D measurements directly on 2D views. As I am working, I want to create a virtual camera that will create new views between the position of my calibrated images. The solution I'm currently…
Broot
  • 3
  • 2
0
votes
1 answer

How will the Intrinsic matrix changes if the dimension of the 3d grid changes?

I have calibrated pictures around an object with unknown dimensions and points. The problem is that the extrinsics calibration is not fairly accurate as I don't exactly know the distance between the camera and the object that it turns around. I can…
Broot
  • 3
  • 2
0
votes
1 answer

Meshroom - What does FeatureExtraction dots color mean in Image Viewer?

I couldn't find any info in the docs. What does each color mean when I check out the features extracted from an image in Meshroom 2021.1?
Iroqas
  • 65
  • 9
0
votes
1 answer

Applying a global coordinate translation to an Obj file

I currently use photogrammetry software and GCP’s to turn drone photos into a georeferenced obj file which I then import to a second software. I have had to switch to a new photogrammetry software which exports the obj and the offset coordinates as…
Cypherdelic
  • 1
  • 1
1 2 3
…
8 9