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Let's go back to a simple 625 line TV picture. A new image is transmitted once every 25th of a second and each line contains about one thousand individual elements or pixels to get a reasonable quality of picture you need at least 256 levels between dark and light This in digital terms means eight bits per pixel. So each second you need to transmit 25 (frames) x 625 lines x 1000 (pixels per line) x8 (bits) this is about 125 million bits per second if you want a colour picture multiply this by three to get the brightness of each individual colour. Basic TV samplers generate data at about one thousand million bits per second.
The technique of sending chrominance signals 'embeded' with the luminance not only meant Black and White TVs carried on working with a colour signal but the bandwidth was not increased by moving to colour. If you were to simply transmit three colour signals you would need three times the bandwidth. I think the max frequency for luminance was about 5 to 5.5 MHz but chrominance was only about 1 MHz. (625 line)It is like a fine detail black and white sketch which is coloured in like a kids colouring book.. Most of the detail is in the black and white sketch but you see a colour picture.
I agree it was a great piece of work but only of you use the PAL system and not the messy and innacurate US NTSC system :-)Erikejah read what I said again I started with a black and white picture and than expanded if to an 8 x 3 = 24 bits per pixcel.