Computer vision systems use frame grabbers to capture individual still frames from an analogue video signal or a digital video stream. Older models only captured and stored a single frame at a time. Frame grabber expansion cards were used to integrate cameras into PCs. Modern frame grabbers can capture multiple frames simultaneously and perform other operations, such as:
- Capturing audio
- Deinterlacing
- Texts graphics overlay
- Image transformations – resizing, mirroring, rotation
Frame Grabbing and Machine Vision
Frame grabbing is an integral component of machine vision. Machine vision is an application of artificial intelligence that enables machines to ‘see’. It uses cameras with varying degrees of sensitivity and resolution to detect objects the way the human eye would. Frame grabbers have evolved over the years to meet the needs of machine vision applications. These applications are increasingly used in consumer electronics, where high data transfer speeds are preferred.
Choosing a Frame Grabber
There are various factors to consider while selecting a frame grabber. These typically pertain to functionality, usability and scale. They include:
Interface and Software – Most frame grabbers come with off-the-rack specifications. You need to consider the camera/grabber interface as vision applications typically require a stack of hardware and software requirements.
Camera Specifications – Camera qualities such as 2D or 3D support and frame rates guide your choice of the frame grabber. Also, consider the conditions in which you use the application.
Multi-source applications – Some processes receive video streams from several sources concurrently. Specific frame grabbers work well in receiving multiple inputs, while others specialize in singular sources.
Applications of Frame Grabbers
Frame grabbers continue to be essential for various machine vision projects due to the benefits they offer. Among the applications include:
Healthcare – Frame grabbing technology enables remote guidance. Consultants can participate in medical procedures in real-time by relaying images by frame grabbers.
Security systems – Security personnel use frame grabbers to automatically receive images during a breach. They are combined with other sensors like motion detectors which trigger the transmission.
Industrial manufacturing – Frame grabbers work with cameras to monitor robotic processes in manufacturing lines.
Consumer Applications – The rise in demand for photography applications has made frame grabbers very popular.
Conclusion
Frame grabbers came into use several decades ago. Although technological advances have emerged on a massive scale, frame grabbers have endured. This is mainly because their underlying technology is highly customizable and adaptable in modern applications.