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An image trigger initiates the capture of single or multiple frames of a digital camera by analysing the signals of its sensor.
A digital camera or digicam is a camera that captures photographs in digital memory. Most cameras produced today are digital, and while there are still dedicated digital cameras, many more cameras are now being incorporated into mobile devices, portable touchscreen computers, which can, among many other purposes, use their cameras to initiate live videotelephony and directly edit and upload imagery to others. However, high-end, high-definition dedicated cameras are still commonly used by professionals.
For capturing and analysing of fast moving objects (e.g. as in quality control of production lines) modern high speed cameras are frequently used. Typically the initiation of an image-series starts as soon as the object is entirely visible in the field of the camera.
By using a so-called "image trigger" this task can be done much faster and more accurately, without the cost and effort of additional equipment as in standard methods (for instance, via cable release).
The on-board "ImageBLITZ" image trigger uses the live picture of the camera itself as a flexible and accurate sensor, with the result that the process synchronisation takes care of itself. [1]
By using CMOS cameras (which provide the information of every single pixel in digitized form) a fast processing of the supplied data is ensured. To prepare the ImageBLITZ, a line segment of a predefined length is set up in the field of view, just where the triggering event is likely to take place. Then the amount of grey level alteration (and its direction from dark to bright or reverse) is set, as well as the minimum number of affected pixels.
In digital imaging, a pixel, pel, or picture element is a physical point in a raster image, or the smallest addressable element in an all points addressable display device; so it is the smallest controllable element of a picture represented on the screen.
In geometry, a line segment is a part of a line that is bounded by two distinct end points, and contains every point on the line between its endpoints. A closed line segment includes both endpoints, while an open line segment excludes both endpoints; a half-open line segment includes exactly one of the endpoints.
In digital photography, computer-generated imagery, and colorimetry, a grayscale or greyscale image is one in which the value of each pixel is a single sample representing only an amount of light, that is, it carries only intensity information. Grayscale images, a kind of black-and-white or gray monochrome, are composed exclusively of shades of gray. The contrast ranges from black at the weakest intensity to white at the strongest.
At each triggering event the camera head now sends a frame (or a set of frames) to the host computer to be processed or archived for further use.
In filmmaking, video production, animation, and related fields, a frame is one of the many still images which compose the complete moving picture. The term is derived from the fact that, from the beginning of modern filmmaking toward the end of the 20th century, and in many places still up to the present, the single images have been recorded on a strip of photographic film that quickly increased in length, historically; each image on such a strip looks rather like a framed picture when examined individually.
A camera is an optical instrument to capture still images or to record moving images, which are stored in a physical medium such as in a digital system or on photographic film. A camera consists of a lens which focuses light from the scene, and a camera body which holds the image capture mechanism.
Cinematography is the science or art of motion-picture photography by recording light or other electromagnetic radiation, either electronically by means of an image sensor, or chemically by means of a light-sensitive material such as film stock.
Microscope image processing is a broad term that covers the use of digital image processing techniques to process, analyze and present images obtained from a microscope. Such processing is now commonplace in a number of diverse fields such as medicine, biological research, cancer research, drug testing, metallurgy, etc. A number of manufacturers of microscopes now specifically design in features that allow the microscopes to interface to an image processing system.
Motion capture is the process of recording the movement of objects or people. It is used in military, entertainment, sports, medical applications, and for validation of computer vision and robotics. In filmmaking and video game development, it refers to recording actions of human actors, and using that information to animate digital character models in 2D or 3D computer animation. When it includes face and fingers or captures subtle expressions, it is often referred to as performance capture. In many fields, motion capture is sometimes called motion tracking, but in filmmaking and games, motion tracking usually refers more to match moving.
An autofocus optical system uses a sensor, a control system and a motor to focus on an automatically or manually selected point or area. An electronic rangefinder has a display instead of the motor; the adjustment of the optical system has to be done manually until indication. Autofocus methods are distinguished by their type as being either active, passive or hybrid variants.
Motion detection is the process of detecting a change in the position of an object relative to its surroundings or a change in the surroundings relative to an object. Motion detection can be achieved by either mechanical or electronic methods. When motion detection is accomplished by natural organisms, it is called motion perception.
Image resolution is the detail an image holds. The term applies to raster digital images, film images, and other types of images. Higher resolution means more image detail.
The EOS 1D Mark II is a professional 8.2 megapixel digital single lens reflex camera (DSLR) camera body produced by Canon. The EOS 1D Mark II was the successor of the EOS 1D and was itself replaced by the Canon EOS-1D Mark III in 2007. It was Canon's first dual-card slot EOS camera with one CF slot and one SD slot that was meant easily to use two dominant card types and have a assurance that once a small sized primary and faster CF slot is full, camera can be used to take photographs when recording was continued on secondary and slower card in critical moment.
A photo finish occurs in a sporting race when multiple competitors cross the finishing line at nearly the same time. As the naked eye may not be able to discriminate between which of the competitors crossed the line first, a photo or video taken at the finish line may be used for a more accurate check. Photo finishes make it less likely that officials will declare a race a dead heat.
A light field camera, also known as plenoptic camera, captures information about the light field emanating from a scene; that is, the intensity of light in a scene, and also the direction that the light rays are traveling in space. This contrasts with a conventional camera, which records only light intensity.
High-speed photography is the science of taking pictures of very fast phenomena. In 1948, the Society of Motion Picture and Television Engineers (SMPTE) defined high-speed photography as any set of photographs captured by a camera capable of 69 frames per second or greater, and of at least three consecutive frames. High-speed photography can be considered to be the opposite of time-lapse photography.
Digital photography uses cameras containing arrays of electronic photodetectors to capture images focused by a lens, as opposed to an exposure on photographic film. The captured images are digitized and stored as a computer file ready for further digital processing, viewing, digital publishing or printing.
An image sensor or imager is a sensor that detects and conveys information used to make an image. It does so by converting the variable attenuation of light waves into signals, small bursts of current that convey the information. The waves can be light or other electromagnetic radiation. Image sensors are used in electronic imaging devices of both analog and digital types, which include digital cameras, camera modules, medical imaging equipment, night vision equipment such as thermal imaging devices, radar, sonar, and others. As technology changes, digital imaging tends to replace analog imaging.
The Canon EOS 30D is an 8.2-megapixel semi-professional digital single-lens reflex camera, initially announced on February 21, 2006. It is the successor of the Canon EOS 20D, and is succeeded by the EOS 40D. It can accept EF and EF-S lenses, and like its predecessor, it uses an APS-C sized image sensor, so it does not require the larger imaging circle necessary for 35 mm film and 'full-frame' digital cameras.
The following are common definitions related to the machine vision field.
Document cameras, also known as visual presenters, visualisers, digital overheads, or docucams, are real-time image capture devices for displaying an object to a large audience. Like an opaque projector, a document camera is able to magnify and project the images of actual, three-dimensional objects, as well as transparencies. They are, in essence, high resolution web cams, mounted on arms so as to facilitate their placement over a page. This allows a teacher, lecturer or presenter to write on a sheet of paper or to display a two or three-dimensional object while the audience watches. Theoretically, all objects can be displayed by a document camera. Most objects are simply placed under the camera. The camera takes the picture which in turn produces a live picture using a projector or monitor. Different types of document camera/visualizer allow great flexibility in terms of placement of objects. Larger objects, for example, can simply be placed in front of the camera and the camera rotated as necessary,or a ceiling mounted document camera can also be used to allow a larger working area to be used.
Rolling shutter is a method of image capture in which a still picture or each frame of a video is captured not by taking a snapshot of the entire scene at a single instant in time but rather by scanning across the scene rapidly, either vertically or horizontally. In other words, not all parts of the image of the scene are recorded at exactly the same instant. This produces predictable distortions of fast-moving objects or rapid flashes of light. This is in contrast with "global shutter" in which the entire frame is captured at the same instant.
A time-of-flight camera is a range imaging camera system that employs time-of-flight techniques to resolve distance between the camera and the subject for each point of the image, by measuring the round trip time of an artificial light signal provided by a laser or a LED. Laser-based time-of-flight cameras are part of a broader class of scannerless LIDAR, in which the entire scene is captured with each laser pulse, as opposed to point-by-point with a laser beam such as in scanning LIDAR systems.