How is the data typically read into the MCU/MPU
In typical reversing camera systems the data may not need to be input to any higher level system. The ultimate end-to end application layer is
'a view what's out the back of the car' to "users eye and brain". Exxentially a camera to monitor system often suffices.
AHD and CVBS are certainly not the only formats you will encounter, but they are widely used in lower cost aftermarket and also OEM equipment.
Many older ones use analog CVBS (Composite Video Blanking & Sync)format.
Useful overview here. These can be viewed on typical composite video analog monitors.
Increasingly, more modern ones are liable to use AHD ("Analog High Definition") - a format common among modern security cameras.
'AHD is able to transmit video, audio and control (OSD or PTZ) over a single coaxial cable instead of requiring separate cables for each transmission.' Power supply is separate (without extra work). It allows substantially better bandwidths than "pure" analog on coax or even paired copper wire. How it works seems to be a well guarded secret - it is used by a wide range of manufacturers but I have not managed to find a technical description with a significant amount of searching. (Any sources gratefuly received).
This useful page covers CVBS and (mainly) AHD in backing camera use.
A number of security cameras that I have seen are able to be switched between AHD and video output.
AHD protocol description here . They mention up to 1080P capability but I am of the understanding (possibly incorrect) that up to 4k is now able to be used. TBD.
AHD CCTV is an analog high definition closed-circuit television video surveillance standard that uses existing coax cable to transmit 720p and 1080p video resolutions HD video from security cameras to DVRs.
AHD is able to transmit up to 1080p video resolution (1920 x 1080) in an uncompressed format over the same standard coaxial cable that is used for standard CCTV cameras.
This uncompressed video format is able to transmit over longer distances than either HD-SDI or Network IP cameras and without the latency and bandwidth issues that are so common with IP Cameras.
Additionally, AHD is able to transmit video, audio and control (OSD or PTZ) over a single coaxial cable instead of requiring separate cables for each transmission.
What is really separating this technology from the rest of the options for HD video transmission is the cost effectiveness of AHD. In most cases AHD is around the same price as the older analog CCTV technology and is far less expensive than HD-SDI or IP Network transmission.
This web search gives many good answers.
This is the same search in image mode - giving many related web pages, one per image.
Suggestion: It is very likely that the above will answer your question. It would be useful if you then self answered the question with a summary for others that provided useful technical specifics. Note that this should not be brand specific but rather a guide to the area of interest