As many of you have noticed, after updating to 4.4.1 and 4.4.2, a recorded video with stock camera is a lot darker than it was on 4.4. It was done probably to increase framerate at night, but crippled low-light video capability. I have noticed that Camera MX by MAGIX allows recording video with lower framerate in low light, but a lot brighter, almost like it was on 4.4, and in full HD resolution.
Below are two samples
Notice higher framerate but darker image.
Notice lower framerate but brighter image.