I’m in a spot where the h264 compression provided by the low-light USB camera is not sufficient for my application. To remedy this, I am likely going to employ a separate compression scheme that would be located topside. To do this, I will need to transmit “raw” video from a camera on the sub via the tether. (I’m aware that transmitting uncompressed video is bandwidth intensive, and I’m prepared to sacrifice frame rate and/or resolution to fit within the bandwidth limitations of the fathom-x). I could use some help understanding what goes on between a camera sensor and the ethernet connection of the fathom-x, in terms of digitizing the output of a camera sensor and manipulating it to be able to be sent via a twisted pair. Is it possible to go straight from a camera to a twisted pair? Unfortunately I’m neither an electrical nor software engineer so I’m a bit over my head here. Any advice or resources to point me in the right direction would be great, thanks!
The latest BlueOS beta version has support for UYUV (raw) and MJPEG encodings when in Pirate Mode.
Digital cameras operate by having photo-sensitive elements that gain some electrical energy when hit by photons. Colour cameras have multiple elements per pixel in order to represent the different colour channels. The “digitisation” effectively involves capturing the energy for the exposure time (which is often configurable), and measuring the resulting voltages.
From there it’s a matter of encoding the data and sending it out to a computer that’s requesting it. Different cameras support different encodings, but UYUV and MJPEG are reasonably common, and some (like our Low-Light HD USB Camera) do onboard H264 encoding, and some more recent cameras (particularly IP cameras) can do H265 encoding too.
BlueOS allows forwarding an encoded stream from a USB camera over ethernet, which then gets converted into the (two wire) HomePlug AV protocol by the Fathom-X, which then gets converted back into an ethernet signal at the topside by the Fathom-X there.
There are also IP cameras, which have an ethernet signal as their output, but if you want to convert an ethernet signal to something that runs over two wires you’ll need something like a Fathom-X board.
Potentially, but I believe it would need to be an analog camera.