Geometry in computer vision | Stereophotogrammetry

Camera auto-calibration

Camera auto-calibration is the process of determining internal camera parameters directly from multiple uncalibrated images of unstructured scenes. In contrast to classic camera calibration, auto-calibration does not require any special calibration objects in the scene. In the visual effects industry, camera auto-calibration is often part of the "Match Moving" process where a synthetic camera trajectory and intrinsic projection model are solved to reproject synthetic content into video. Camera auto-calibration is a form of sensor ego-structure discovery; the subjective effects of the sensor are separated from the objective effects of the environment leading to a reconstruction of the perceived world without the bias applied by the measurement device. This is achieved via the fundamental assumption that images are projected from a Euclidean space through a linear, 5 degree of freedom (in the simplest case), pinhole camera model with non-linear optical distortion. The linear pinhole parameters are the focal length, the aspect ratio, the skew, and the 2D principal point. With only a set of uncalibrated (or calibrated) images, a scene may be reconstructed up to a six degree of freedom euclidean transform and an isotropic scaling. A mathematical theory for general multi-view camera self-calibration was originally demonstrated in 1992 by Olivier Faugeras, QT Luong, and . In 3D scenes and general motions, each pair of views provides two constraints on the 5 degree-of-freedom calibration. Therefore, three views are the minimum needed for full calibration with fixed intrinsic parameters between views. Quality modern imaging sensors and optics may also provide further prior constraints on the calibration such as zero skew (orthogonal pixel grid) and unity aspect ratio (square pixels). Integrating these priors will reduce the minimal number of images needed to two. It is possible to auto-calibrate a sensor from a single image given supporting information in a structured scene. For example, calibration may be obtained if multiple sets of parallel lines or objects with a known shape (e.g. circular) are identified. (Wikipedia).

Video thumbnail

Camera Parts

Cameras come in many different shapes and sizes, so the exact buttons and features will vary. However, there are a few basic parts that almost all cameras have. We hope you enjoy! To learn more, check out our written lesson here: https://edu.gcfglobal.org/en/digitalphotography/

From playlist Digital Photography

Video thumbnail

Mirrorless Cameras

Mirrorless Cameras are pocket-sized alternatives to DSLRs that feature interchangeable lenses. These cameras use a digital screen or an electronic viewfinder to display what the camera sees. One of the best advantages is that you will be able to see how settings such as shutter speed, ape

From playlist Digital Photography

Video thumbnail

Camera Sensor

Every digital camera has a sensor located behind the lens. The sensor is the part that actually captures the photo, much like the roll of film in a film camera. We hope you enjoy! To learn more, check out our written lesson here: https://edu.gcfglobal.org/en/digitalphotography/

From playlist Digital Photography

Video thumbnail

Shot Types Part 1

Sometimes a closeup works best, but other times you may want a wider-angle shot. You can experiment by moving closer and farther away from your subject, or by using your camera's zoom. We hope you enjoy! To learn more, check out our written lesson here: https://edu.gcfglobal.org/en/digita

From playlist Digital Photography

Video thumbnail

ISO Sensitivity

Digital cameras can adjust the sensitivity of the sensor, and this is known as the ISO number. For example, ISO 100 is a lower sensitivity, so it requires more light to create a good exposure. We hope you enjoy! To learn more, check out our written lesson here: https://edu.gcfglobal.org/e

From playlist Digital Photography

Video thumbnail

Compact Cameras

Compact cameras are designed to be affordable, convenient, and easy to use. They don’t feature a viewfinder, utilizing instead a screen that shows the frame or image. Compact cameras are great if you’re taking a trip and don’t want to carry something big and bulky. We hope you enjoy! To

From playlist Digital Photography

Video thumbnail

DSLR Cameras

Short for "digital single-lens reflex," DSLR Cameras are large cameras with interchangeable lenses that can take very high-quality photos. We hope you enjoy! To learn more, check out our written lesson here: https://edu.gcfglobal.org/en/digitalphotography/

From playlist Digital Photography

Video thumbnail

Blender for Video Editing: Working with Landscape and Portrait Movies

In this video we show how to rotate and scale portrait movies to fit in landscape movie projects. This is useful if you have video clips that are filmed in portrait mode (ie vertically) and you would like to rotate, scale, crop, and/or move them to include them in a project that is in wid

From playlist Blender as a Video Editor

Video thumbnail

DWARF 2 Smart Telescope - In-depth Review & Results

Hey folks, dwarflab.com sent me their newest smart telescope: DWARF II and here is my in-depth review and the results from different imaging nights. We cover: - Hardware specs - Use cases - App design and handling - Astro-modus - Imaging procedure - Pros and cons of DWARFII - final t

From playlist Fourier

Video thumbnail

EEVblog 1420 - Mailbag

1 hour Mailbag! Forum: https://www.eevblog.com/forum/blog/eevblog-1420-mailbag/ SPOILERS: 00:00 - Pleo the Dinosaur! The designer talking about Pleo: https://www.youtube.com/watch?v=BOba_zGoZq8 The Commodore Collector: https://www.thecommodorecollector.com/ 06:23 - Amazing workbench of t

From playlist Mailbag

Video thumbnail

Stanford Seminar - Robotic Autonomy and Perception in Challenging Environments

Christoffer Heckman CU Boulder January 17, 2020 Perception precedes action, in both the biological world as well as the technologies maturing today that will bring us autonomous cars, aerial vehicles, robotic arms and mobile platforms. The problem of probabilistic state estimation via sen

From playlist Stanford AA289 - Robotics and Autonomous Systems Seminar

Video thumbnail

Tracker Tutorial

Tracker is a part of the Open Source Physics project. It is a wonderful tool that can be used to measure motion in videos, turning a video camera into a data-gathering instrument. This use of Tracker relates to a kinematics lesson early in a physics course: the motion of a projectile mov

From playlist Lessons of Interest on Assorted Topics

Video thumbnail

EEVblog #1239 - Mailbag

More Mailbag! Forum: https://www.eevblog.com/forum/blog/eevblog-1239-mailbag/ SPOILERS: Dodgy Plugpack Teardown & Discussion 9:40 eSATA cage thingo teardown 11:47 Ford Car Stereo teardown 18:34 Back To The Future Delorean Time Circuits https://www.marmosetelectronics.com/time-circuits-cl

From playlist Mailbag

Video thumbnail

Deep Sky Astrophotography on a Monday

My Astrophotography Gear: Starfield 50mm Autoguiding Package: https://bit.ly/2s6KRlA Explore Scientific ED140 APO Telescope: https://bit.ly/2J7Vv5a iOptron CEM60 Equatorial Mount: https://bit.ly/2IMYhgS Baader Moon and Skyglow Filter: https://amzn.to/2y6KFrW STC Astro Duo-Narrowband Filte

From playlist What Fraser's watching

Video thumbnail

ZuriHac 2016: Functional Programming at LumiGuide

A Google TechTalk, July 22, 2016, presented by Bas van Dijk ABSTRACT: I will give an introduction to LumiGuide and talk about how we use Haskell to build our bicycle detection and guidance systems. The first part of the talk will be non-technical but in the second part I will dive deep i

From playlist ZuriHac 2016

Video thumbnail

Curiosity Rover Report (May 9, 2013): 'Spring Break' Over: Commanding Resumes

Curiosity gets new software and new capabilities for the long trek to Mt. Sharp.

From playlist Curiosity Rover Reports

Video thumbnail

画像処理・コンピュータビジョン・ディープラーニング R2018a 最新機能紹介

画像処理・コンピュータビジョンビデオシリーズ:http://ow.ly/uIRM30knLtf MATLABで始めるディープラーニング:http://ow.ly/4Kjd30knLzQ 無料評価版はこちら:http://ow.ly/cdie30kl7On 画像処理やコンピュータビジョンの技術は、セキュリティー・バイオ・医療・自動運転・検査装置など様々な分野で必要とされています。画像処理の分野に多くのアルゴリズムや問題解決へのアプローチがあり、最適解を得るために様々な組み合わせを試す必要があります。 MATLAB®を使用すると、例えばCコードで記述すると膨大なコード量になっ

From playlist 画像処理とコンピュータビジョン (Japanese)

Video thumbnail

Macro filming Hard Disk Drive

Filters being used: - High and low frequency denoising - Spline-based image resizing to FullHD - Image stabilization http://kostackstudio.de

From playlist Video Experiments

Video thumbnail

Hypercentric optics: A camera lens that can see behind objects

Telecentric and hypercentric optics are very different from our eyes or normal camera lenses. They have "negative" perspective or no perspective, respectively, leading to very unusual images. In this video I show how to use a common fresnel lens in the creation of your own telecentric op

From playlist Optics

Video thumbnail

RailsConf 2021: Exploring Real-time Computer Vision Using ActionCable - Justin Bowen

Learn about combining Rails and Python for Computer Vision. We'll be analyzing images of cannabis plants in real-time and deriving insights from changes in leaf area & bud site areas. We'll explore when to use traditional statistical analysis versus ML approaches, as well as other ways CV

From playlist RailsConf 2021

Related pages

Camera matrix | Camera resectioning | Bundle adjustment | Pinhole camera model | 3D projection | Euclidean space | Epipolar geometry | Deconvolution