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9 votes

How do I get the most accurate camera calibration?

I decided to post this answer here because a while back, this came up as the top result in Google and its suggestions helped me. So I decided to share my experience too. Having spent countless hours ...
Maghoumi's user avatar
  • 191
7 votes

How do I get the most accurate camera calibration?

Here is a list of 'best practices' for camera calibration which I originally posted here: https://calib.io/blogs/knowledge-base/calibration-best-practices Choose the right size calibration target. ...
Jakob's user avatar
  • 146
4 votes

Camera Calibration - why do you have to move the calibration board?

This is due to the optimization problem being rather high-dimensional (around 11 parameters). With only a single observation of the calibration board, there would be multiple possible combinations of ...
Jakob's user avatar
  • 146
4 votes

Detecting bullet holes using Python with camera or sensors

I can't really comment on the machine vision part, other than any question that asks "How do I do <some signal processing task> in <some language>" is fairly naive. The way you ...
TimWescott's user avatar
  • 11.9k
3 votes

How to estimate radial distortion from lens characteristics?

There is a lot of variability because distortion can be compensated for optically and lens designs differ. Some lenses are marketed as rectilinear, most not. You would be making the distortion worse ...
Olli Niemitalo's user avatar
2 votes

What are characteristics of shadows in an image given an outdoor setting from an image processing point of view?

The characteristics of the shadow are as follows: It is always dark regardless of the color of the object or the color of the light used to make a shadow It only shows a dark outline of the object It ...
amina saja's user avatar
2 votes
Accepted

Capturing images on fast moving conveyor belt

Try reducing exposure time if your camera allows that. With the short exposure time the conveyor belt should be well-lit. If that is not enough, a common solution is to use a flash which is ...
Olli Niemitalo's user avatar
2 votes

Where to get the Kodak PhotoCD raw image dataset?

http://r0k.us/graphics/kodak/ does link to Kodak PhotoCD contents with 2048x3072 images. It is not what is called "raw" as those are using 4:2:0 subsampling (so not lossless at all) and ...
Валерий Заподовников's user avatar
2 votes
Accepted

Oversampled Binary Image Sensor vs Active Pixel Sensor(CMOS)

The success of your camera depends on too many factors! and they're out of the scope of this page. If the dynamic range requirements of your application are not too demanding then you could take ...
VMMF's user avatar
  • 1,078
2 votes
Accepted

Pinhole camera model from houdini parameters

This is a long topic to fully explain. I will try to write shortly, so please excuse the brevity. Standard computer vision projection (ignoring distortion like Houdini) follows: $$ \mathbf{x} = \...
Tolga Birdal's user avatar
  • 5,465
2 votes
Accepted

Response function for digital camera pixel

If I understand you correctly, what you are asking for is called camera response function (CRF) and in general it is nonlinear and depends on camera device. For fixed device denote its CRF by $f$. ...
Slup's user avatar
  • 136
2 votes

Why is my laser beam intensity profile not Gaussian?

What could cause such a shape? Could it be due to the laser source which could not be perfectly single-mode? Or could it be due to the sensor? There is nothing particularly wrong with the "...
A_A's user avatar
  • 10.6k
2 votes

Calibration using Camera Calibration Toolbox for Matlab vs OpenCV

Depending on the lens-distortion model used, the achievable accuracy can be significantly different: https://discorpy.readthedocs.io/en/latest/tutorials/methods.html Have a go with another approach ...
entropi99's user avatar
2 votes

Fixing distortion in photographic reproductions

I answered a related question in SO some time ago. Briefly, you can work your setup through a standard camera calibration procedure, and you have the option of "freezing" the focal length to ...
Francesco Callari's user avatar
2 votes

Image resolution vs. dimensions

The two terms, "image resolution" and "image dimensions", are often used interchangeably in colloquial speech, but they absolutely have distinct technical definitions, especially ...
Ahsan Yousaf's user avatar
  • 1,204
2 votes

Image resolution vs. dimensions

The term “resolution” is much, much older than digital imaging, and was first used when talking about microscopes. Resolution is a microscope’s ability to distinguish separate objects. A resolution of ...
Cris Luengo's user avatar
  • 2,359
1 vote

Oversampled Binary Image Sensor vs Active Pixel Sensor(CMOS)

At the time when the original question was asked, there was no hardware technology to physically construct an oversampled binary image sensor. Two years later - Technology is now slowly moving towards ...
Atul Ingle's user avatar
  • 4,124
1 vote
Accepted

Is it worth recording 4K resolution from a 1080p camera input?

I do not know how the choice between 1080p and 4K affects the recording quality in Ecamm live. But it makes sense to convert a high-bitrate 1080p video to high-bitrate 4K video before uploading to ...
Olli Niemitalo's user avatar
1 vote

Find camera pose by knowing triangle coordinates

No. No. You can't. Not completely at least. With only three points, the math has two solutions. Your triangle could be tilted in one of two positions. Like picking a square root. From a single ...
Cedron Dawg's user avatar
  • 7,520
1 vote

Understanding legacy code: Algorithm to remove radial lens distortion

Welcome to SP. I happen to have already answered your question in SO: see point 2 of my answer here.
Francesco Callari's user avatar
1 vote
Accepted

Camera Pose Estimation from Vanishing Points

You can use the vanishing points to calibrate the camera. I recommend reading Chapter 8.6 of Multiple View Geometry in Computer Vision [ http://www.cambridge.org/9780521540513 ] Even better, if you ...
sergiohc101's user avatar
1 vote

Camera Calibration - why do you have to move the calibration board?

Digital cameras sample the incoming optical EM or photonic field with a fixed grid of CCD or CMOS transistors. Since the sampling grid (rectangular or perhaps hexagonal) is not angularly symmetric, ...
hotpaw2's user avatar
  • 35.2k
1 vote

Is it possible to generate depth map from graycode sequence without using printed calibration patterns?

... if the camera's intrinsics are known and calibrated, is it possible to generate the depthmap fully automatically through a graycode sequence without any manual calibration process ? Yes, provided ...
A_A's user avatar
  • 10.6k
1 vote
Accepted

Camera calibration and extrinsic parameters for perspective transformation

You can bypass all the OpenCV stuff, and create a custom mapping from pixel location to real world location of the form: $$ x = A_x m^2 + B_x mn + C_x n^2 + D_x m + E_x n + F_x $$ $$ y = A_y m^2 + ...
Cedron Dawg's user avatar
  • 7,520
1 vote

Camera calibration and extrinsic parameters for perspective transformation

For your application, here are the steps I would follow: Calibrate the camera and obtain the intrinsics - You have obviously done that and corrected for the distortion already. ...
Tolga Birdal's user avatar
  • 5,465
1 vote

computer vision - How to correctly calibrate my camera with a wide angle lens using openCV?

If you haven't followed this tutorial on camera calibration with OpenCV, do it. It's well explained and the code is pretty much ready to go. And if your goal is to calibrate your camera using the ...
Dark Sinus's user avatar
1 vote

Near Infra-Red Cameras for Eye-Tracking

For my DIY projects I have used ps3 eyetoy camera which can capture 120 fps. Only downside was difficulty in removing IR block filter with a filter blocking the visible range. There used to be open ...
keoxkeox's user avatar
  • 111
1 vote

Why are two cameras mounted in paralle in stereo application?

When you say cameras are parallel it only means that the center pixels are parallel. Every pixel has a different angle, and that refers to the overlapping regions you were talking about. Actually ...
Cherny's user avatar
  • 471
1 vote

the position of image plane in optical imaging

I agree with user lxg that it is a notational difference, as for the pinhole camera we always have: $$S_2 = f$$ That is not necessarily true for a camera with a lens. A pinhole camera is not the ...
Olli Niemitalo's user avatar
1 vote

camera movement calculation

Is what I'm after even possible? yes. Let's start with the simplification your camera was a perfect pinhole camera. For starters, imagine you pick an arbitrary point object in your scene. You then ...
Marcus Müller's user avatar

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