The MAX9271/2 transmits in units of frame. To eliminate the DC component during transmission, a 8b/10b encoding is performed prior to transmission. As such, the 24-bit and 32-bit data are encoded into 30-bit and 40-bit data, respectively, shown below.
The transmission rate on the coaxial or twisted pair cables is calculated below:
(Row pixel x column pixel) / 2 x fps x 1.25 x 30 (24-bitmode) or
(Row pixel x column pixel) / 2 x fps x 1.25 x 40 (32-bitmode)
where the 1.25 is a correction made for the Hblank and Vblank. “/2” is there since each frame transmits data from two pixels.
If the clock speed of the pixels is known, the calculation is as follows:
Pixel clock (PCLK) rate x 30 (24-bit mode) or
Pixel clock (PCLK) rate x 40 (32-bit mode)
For the common 720P signal with a 30 fps camera, the maximum transmission rate of the coaxial cable or twisted pair cable is:
(720 x 1080) / 2 x 30 x 1.25 x 30 = 437Mbps (24-bit mode), or
(720 x 1080) / 2 x 30 x 1.25 x 40 = 583Mbps (32-bit mode)