Hyper-Communication 289

Hyper-Communication 289 My in-person experience has much higher bandwidth than even a DVD. It may even have infinite bandwidth. Physicists argue whether space-time is quantized but, for now, we will look at what would be needed to reproduce the experience faithfully on modern digital recording equipment. Digitization When something is converted to digital form, it goes through a number of steps. First, some way must be found to chop the thing into small parts in space and time. Then each of these parts is sampled with a sensor to give an electrical signal and, finally, this signal is measured and turned into a number. Old microphones used carbon granules. As the sound waves passed through them, the granules were shaken and made better contact with each other. Connecting a battery across the granules gave a varying voltage. Modern microphones use a variety of technologies. The preference of most recording artists today is the electret microphone. A coil moves inside a magnet generating a varying voltage which is translated into a voltage as before. Next we use a fast running clock and measure the voltage on each tick giving us a sequence of numbers. We have created a near perfect record of the sound, and we can prove this by recreating the sound through a loudspeaker. This is what happens every time you listen to your iPod. To digitize film, each frame must be split in space as well as time. On each tick of the clock, a process scans left to right and top to bottom to form a one-dimensional stream of numbers that records the image. The system cuts the picture up into little elements called pixels, standing for picture elements. Each small square has its average color measured for red, green, and blue content coded as a number. Digitization techniques have become the dominant way electronics work in the home, and digitization circuits are now ubiquitous. Reality How big is reality? Setting aside for a moment the problem that it might be infinite, we need to reproduce all the elements that go to make it up. A normal DVD has an image of 720 by 576 pixels with 16 bits of color depth and a frame rate of 25 frames per second. The eye, however, is considerably better than this and a DVD does not fool it. HD video HOUSE_OVERSIGHT_015979