Page 262 - The ROV Manual - A User Guide for Remotely Operated Vehicles 2nd edition

Today, analog standards have given way to new digital television standards worldwide, but the original NTSC and PAL frame rate, line resolution, and aspect remain (defined below). The old NTSC and PAL formats are now folded into different standards which have been expanded to include the new high-definition digital television standards. The current non-governmental organi- zation developing television industry consensus standards in the United States is the Advanced Television Systems Committee (ATSC) located in Washington, DC. Standards issued by the ATSC are typically adapted by most governmental regulatory organizations (e.g., in the United States, the FCC). As the frame rate and the line count are embedded into other standards, the NTSC and PAL designations currently only refer to the method of embedding color coding into the transmission.
Various other international standards organizations are involved with consensus standards for the video and motion picture industries including:
Advanced Television Systems Committee (ATSC—www.atsc.org)
Association of Radio Industries and Businesses (ARIB—www.arib.or.jp)
Cable Television Laboratories (CableLabs—www.cablelabs.com)
Consumer Electronics Association (CEA—www.ce.org)
Digital Video Broadcasting (DVB—www.dvb.org)
European Broadcasting Union (EBU—www.ebu.ch)
European Telecommunications Standards Institute (ETSI—www.etsi.org) International Electrotechnical Commission (IEC—www.iec.ch)
Institute of Electrical and Electronics Engineers (IEEE—www.ieee.org) International Organization for Standardization (ISO—www.iso.org) International Telecommunication Union (ITU—www.itu.int)
Society of Cable Telecommunications Engineers (SCTE—www.scte.org) Society of Motion Picture and Television Engineers (SMPTE—www.smpte.org) Video Electronics Standards Association (VESA—www.vesa.org)
10.2 How it works
10.2.1 The camera
The camera functions as a transducer converting light into electrical pulses through sensing of light frequency and intensity with use of the photoelectric effect. Screen position and intensity of light levels entering a camera’s lens are measured and converted to electrical signals for output as video signals. With use of a photoelectric converter (converting light into electrons), the electrons are converted sequentially into voltages (per pixel) by the electronic circuit while a synchronizing sig- nal is added to synchronize position information with the voltages for rendering a picture (Figure 10.1). The camera itself is made up of a lens channeling light to a series of light-sensing elements mounted to a sensor plate connected to a conductor (Figure 10.2). The signal is then trans- mitted to a video capture device (for later viewing) or to a display for real-time viewing.
Traditional electron beam “vacuum tube cameras” have given way to solid-state charge-coupled devices (CCD) and complementary metal
oxide
semiconductor (CMOS) as the optical image sen- sor (device converting optical images to electrical signals). Both CCD and CMOS sensors are
10.2 How it works 251