ABSTRACT
Image processing begins with the image; hence, image acquisition is the rst key step to investigate. Both the hardware and soware used for acquisition can appear quite dierent, depending on the type of image source and interface. is can vary from video cameras with appropriate frame grabbers (either on a card internal to the computer or an external device connected to it by a parallel or serial interface), to digital cameras with their own serial or SCSI interfaces, to slide or atbed scanners usually with an SCSI or USB interface. Connecting this hardware properly and installing the appropriate soware drivers is sometimes confusing, particularly under Windows. e following is an abridged list of common sources for image acquisition:
Real-world 3D objects are converted into digital images•
Cameras (CCD, CID, CMOS)•
Infrared cameras•
Ultrasounds•
X-rays and radiography•
Magnetic resonance imaging (MRI)•
Satellite imagers• Scanners•
2.1.1 Cameras
e cameras and recording media available for modern digital image processing applications are changing at a signicant pace. Various types of technologies are available in the market, such as charge-coupled device (CCD), charge injection device (CID), and complementary metal oxide semiconductor (CMOS) cameras. e techniques that are used to characterize the basic type of CCD camera remain “universal” and can be transparently applied to other technologies. e basic principle of any charge-based camera is the emission of charges proportional to the incident light on these cells from the photosensitive elements or cells present in the main imaging hardware.
