Digital antishaker

Please, note that this article is automatically translated from Russian into English, so the translation may not be accurate.

Anti-shaker - Stabilizer images (one way). Used in photo and video cameras, telescopes and other equipment that uses optical elements to capture the image. Compensates for the intrinsic angular camera motion (trembling) that could adversely affect the quality of the displayed image.

In addition, the use of the image stabilizer to reduce the file size, which may be crucial condition for the transfer of data via electronic communication channels with low bandwidth.

Types of anti-shakers

There are several methods of image stabilization. Are commonly used mechanical (optical) and digital methods.

Optical Image Stabilizer

Is a mechanical device, similar in principle of the gyroscope. Optical elements of the group have some degree of freedom, which allows lenses to shift relative to the matrix (light-absorbing element), in response to external stimuli (shaking hands of the operator, vibration). Thus, the luminous flux is projected onto the matrix (or film) without distortion.

One of the drawbacks of the optical stabilizer is using in its production of expensive and complex mechanical components. Furthermore, the presence of several groups of optical elements can affect the luminosity of the lens, that is, the ability to provide a particular level of illumination at the image of the brightness of the object.

Digital Image Stabilizer

Uses software algorithms. Is an inexpensive alternative to optical stabilizer. Electronic method to minimize the effects of camera shake under the influence of the external environment during the recording and / or transmission of the image (watch video).

In the digital stabilizer no moving parts (in particular, the optical group of several lenses). This positive effect on the reliability of cameras, which have fewer components subject to breakage. In addition, the use of digital image stabilizer allows you to increase the sensitivity of light-absorbing elements (the matrix). Also, the reaction rate digital stabilizer can be higher than the optical one.

Anti-shaker application

As mentioned above, anti-shakery (image stabilizer) are used in a wide range of techniques to capture images.The important role played by anti-shakery in video surveillance systems, elements of which may have environmental impact. This may be the natural vibration (wind, earthquake, for example) and man-made (a passing train hard, running alongside construction work of vibration equipment, etc.).

For the organization fully operational surveillance and intelligence necessary to provide high-quality capture and transmission of video data received by means of observation. Data is received and processed by the system, equipped with image stabilizer, make the audience perception of pictures clearer and more understandable and thus more comfortable and informative.

In addition, the resulting image more amenable to high-quality compression. This affects the size of the file, which is important when transmitting data to the remote device video output: the lower the "littered" images (due to camera shake), the smaller volume is a file.

The image quality also affects the accuracy of video analytics, will eliminate false positives that may arise due to camera shake.

Digital anti-shaker

The digital image stabilizer uses an intelligent algorithm that allows you to compensate for jitter and to analyze the scene. When a digital image stabilizer can be used several techniques. One of them allows you to remove the resulting image on the sensor in the opposite direction of motion, compensating for external influence (bias chamber due to a gust of wind, for example).

The second technique involves digital processing of the image in real time: filters reduce the intensity of the blur (blur), or completely eliminate it due to software algorithms.

Possible difficulties in using digital anti-shaker

Image stabilization can be difficult under certain circumstances. For example, a camera that uses the imperfect algorithms analysts may perceive a large moving object in the background. In this case, embedded analytics will try to make adjustments to an image, by adopting the motion of the object for its own camera movement.

Thus, the systems used in videoanaliticheskih algorithm should be able to distinguish between background and foreground object, which can change its position in space. Anti-shaker thus should not interpret the motion of the object as the camera moves.

Perhaps the emergence of another negative effect - an increase in the sensitivity of light-absorbing element increases image noise. This noise prevents the analysis of video data, preventing the detection of objects and events.

Features of the algorithm of "Synesis"

Algorithm for digital image stabilization, developed by "Synesis", has characteristics that help to solve the set for video analytics systems problem. In combination with stable detection algorithm on the variability of the background and functions of the suppression effect of moving objects, implementing solutions company Synesis provides an opportunity for effective use of video surveillance systems.

The algorithm used allows to achieve optimal performance, video analytics, providing undistorted reception of video data that is necessary for correct processing of information.

Solution is compatible with the x86 (32-bit architectures), and TI DaVinci, which is considered one of the most advanced technologies for processing digital video.