HDR images with Elphel cameras
The purpose of this project is to get HDR images using an Elphel camera.
There are several ways how to increase the dynamic range and to achieve HDR images:
Autoexposure Daemon HDR Functions
The autoexposure daemon running in the camera can alternate exposure times quickly meaning recording at maximal FPS with 2 alternating exposure times is possible. This HDR-video can be record just like any other normal video with the harddisk-recorder camogm or streamed over the network.
You can do exposure bracketing manually with a PHP script. Just set exposure time -> capture a single frame -> change exposure time -> capture another image, etc. This will be slower than using the daemon but you have finer control over how many brackets you want and how big the EV steps between the brackets are, etc. This is best suited for still image recording where speed is not so much of an issue.
JP4 HDR is a special raw color format that can capture a higher dynamic range in an image without introducing any artifacts as result from combining images captured at different times (exposure bracketing). Though the post processing code to develop the images is still experimental.