01-10-2021, 01:56 PM
30 years ago I worked for a company that made specialist CCTV cameras.
There first solid state camera used a double height CCD chip with half of it masked physically with a blackened label.
The pixels in the exposed bit absorbed light and charged to an analogue level. During the blanking period the whole lot was transferred parallel port style to the masked bit where it was read of serially and buffered for onward transmission between the sync pulses of the 75 ohm output. Yes that is right early CCD cameras really were analogue.
The whole camera was about the same size as a hand held colour one of the period. I got to see colour CCD cameras after I moved on to another company.
Modern cameras use more layers in the head chip with a layer of RAM to store the analogue pixel outputs after transfer as above where they will just be digitised as they are read off serial port style.
There will be some kind of frame marker to set the resolution of the display software.
The processing software dismantles the signal and converts it to a single frame plus updates.
Those sweeping pan shots of the analogue days will disappear due to the amount of bandwidth they use up.
There first solid state camera used a double height CCD chip with half of it masked physically with a blackened label.
The pixels in the exposed bit absorbed light and charged to an analogue level. During the blanking period the whole lot was transferred parallel port style to the masked bit where it was read of serially and buffered for onward transmission between the sync pulses of the 75 ohm output. Yes that is right early CCD cameras really were analogue.
The whole camera was about the same size as a hand held colour one of the period. I got to see colour CCD cameras after I moved on to another company.
Modern cameras use more layers in the head chip with a layer of RAM to store the analogue pixel outputs after transfer as above where they will just be digitised as they are read off serial port style.
There will be some kind of frame marker to set the resolution of the display software.
The processing software dismantles the signal and converts it to a single frame plus updates.
Those sweeping pan shots of the analogue days will disappear due to the amount of bandwidth they use up.
