nlitz88 / parkingdetection_meter Goto Github PK

Very primitive protocol will go something like this:

1. Client sends height of plate crop image as unsigned 16 bit integer (8 bits too small for large crop heights/widths)
2. Client sends width of plate crop image as unsigned 16 bit integer
3. Client sends over number of bytes in crop (n)
4. Client sends n bytes, one after another.

Could also include a preamble/postamble if we want to wrap each transmission, but not strictly necessary. Could potentially prevent some confusion.

Also, down the road, could do TCP over serial if we find that we really need delivery guarantees, and could even use some CRC on top of that to ensure reliable delivery. Not so critical for images, though. PySerial provides a TCP implementation, and it also looks like there's an official Arduino library for this.

I.e., create a header file that defines the interface that should be implemented by a given protocol.

For example: Maybe the interface has a function called send_plate_image(void *plate_crop_buffer, hub_t hub)

• If we have an HTTP implementation of this interface, the definition of send_plate_image might create a new connection to the specified hub, where the hub in this case is an IP Address and port, and then send a message to the API via a URL.