A novel filter that enhances underwater video footage in remotely operated vehicle systems is well suited to both military and civilian applications.When looking under water with a camera, the user is hampered by low contrast, color changes, and interference due, for example, to camera noise and floating particles such as sea snow. Especially with cameras mounted on remotely operated vehicle (ROV) systems, common in both military and civil applications, these effects make observation more difficult and tiring. Applying image enhancement significantly eases the task of observation. Here, we describe a software solution for enhancing underwater imagery. Wherever possible, we have reused algorithms based on earlier developments in the area of compound security 1 and UAV (unmanned aerial vehicle) image 2 enhancement, and have transformed and extended them for this underwater case. Our method comprises three techniques.A smart temporal average filter called noise reduction simultaneously reduces noise and sea snow. Noise reduction requires first estimating the camera motion. While performing this subpixel estimation, adaptive image integration reduces temporal noise, which in turn decreases sea snow. Further details on image registration for enhancement purposes are available elsewhere. 1 Underwater imagery may also suffer from low contrast, especially in murky waters and when observing over larger distances. Amplifying the small contrast variations achieves a higher, evenly divided contrast for the entire image. [3][4][5] Finally, imagery may undergo a shift in hue with respect to the original scene due to the filtering of the water. A color correction algorithm restores the original colors of the scenario as well as possible. This algorithm is applied prior to the display of the imagery. Note that color correction must be designed from scratch for the specific underwater case. 6 Many hardware solutions for contrast enhancement exist. A main drawback of such methods is that applying only contrast enhancement will also amplify camera noise and sea snow. We have implemented the combination of noise reduction, local adaptive contrast enhancement, and color correction on a commercial off-the-shelf (COTS) laptop used to control an ROV equipped with an NVIDIA Compute Unified Device Architecture (CUDA)-capable graphics processing unit (GPU). The local adaptive contrast enhancement and color correction are applied by the GPU and the noise reduction by the central processing unit (CPU). The result is displayed directly on the laptop. However, in other implementations alternative choices can be made for the hardware. Figure 1 shows the flowchart of our method.We developed and tested our approach in an operational navy environment, in collaboration with Dutch Ministry of Defence ROV operators. For the development and tuning of the algorithms, we used reference video footage, acquired in the murky waters of the Netherlands. We tested the software using data from other but similar underwater scenarios. Figure 2 shows snapshots o...