An inexpensive remotely-operated video recording system for continuous behavioral observations

Abstract

12Video recording technology is an important tool for studies of animal behavior because it 13 reduces observer effects and produces a record of experiments, interactions among subjects, 14 and contextual information, however it remains cost prohibitive for many researchers. Here we 15 present an inexpensive method for building a remotely-operated video recording system to 16 continuously monitor behavioral or other biological experiments. Our system employs Raspberry 17Pi computers and cameras, open-source software, and allows for wireless networking, live-18 streaming, and the capacity to simultaneously record from several cameras in an array. To 19 validate this system, we continuously monitored home-cage behavior of California mice 20 (Peromyscus californicus) in a laboratory setting. We captured video in both low-and bright-light 21 environments to record behaviors of this nocturnal species, and then quantified mating 22interactions of California mouse pairs by analyzing the videos with an open-source event 23 logging software. This video recording platform offers users the flexibility to modify the 24 specifications for a range of tasks and the scalability to make research more efficient and 25 reliable to a larger population of scientists. 26 behavior during the dark period while the room was illuminated with red lights and infrared LED 131 lights. We found that using two modules, each set to parameters optimized for each light 132 environment, was the most effective way for us to obtain high quality video across the entire 133 light-dark cycle, however a single camera can be programed to adjust parameters at different 134 times through the day. In our setup, the size of the files produced from using a single module 135 exceeded the capacity of the micro-SD card, and we found that adding as second module was 136 more cost effective that using a high-capacity micro-SD card. 137 138 Rev. 1978;43(5):623-43.

Broad‐scale applications of the Raspberry Pi: A review and guide for biologists

“…(2018) also used a system of linked cameras but used it to acquire video data of rats in a large open space, and used a connected Arduino to accurately synchronise the subunits. Weber and Fisher (2019) continuously recorded the behaviour of multiple mating pairs of captive mice across several reproductive cycles. Maia Chagas et al.…”

Pi USB Cam: A Simple and Affordable DIY Solution That Enables High-Quality, High-Throughput Video Capture for Behavioral Neuroscience Research

“…At the heart of the software design, the Show-me webcam firmware enables Raspberry Pi cameras to become an out-of-box, plug-and-play USB camera. In contrast, most, if not all, other DIY solutions require some level of programming proficiency to unlock even the most basic functionalities of the microcomputer and related hardware (Saxena et al, 2018;Singh et al, 2019;Weber and Fisher, 2019;Clemensson et al, 2020;Centanni and Smith, 2021). While preferred file format and location where they can be accessed for offline analysis using sophisticated behavioral tracking algorithms such as ezTrack (Pennington et al, 2019) and DeepLabCut (Mathis et al, 2018).…”

“…While the Pi USB Cam offers an easy-to-use, flexible, and affordable option for behavioral neuroscientists to acquire video recordings, several limitations of our system should be noted. Previous approaches using Raspberry Pi cameras are designed such that the microcomputer performs the heavy lifting of video encoding (Saxena et al, 2018;Singh et al, 2019;Weber and Fisher, 2019;Clemensson et al, 2020;Centanni and Smith, 2021). The advantage of such a design is that it has no inherent limits on scalability other than the number of cameras an individual can purchase.…”

“…However, lack of active maintenance and development quickly rendered it obsolete as the current generation of Raspberry Pi board (4B) no longer supports the legacy OS (Raspbian Stretch) for which it was developed. Recently developed solutions that use the Raspberry Pi Camera in its most basic form to acquire video are less demanding in terms of debugging and updating (Saxena et al, 2018;Weber and Fisher, 2019;Clemensson et al, 2020;Centanni and Smith, 2021). However, these out-of-the-box options suffer from limited functionality, often lacking the capacity to live preview and record at the same time, or interface with closed-loop behavioral control systems.…”

Automated behavioral scoring: Do we even need humans?

“…The resulting video is then scored by the open‐source computer vision framework BioTracker 21,23 . In 2019, Weber and Fisher posted a preprint describing a continuous home cage recording system using the Raspberry Pi platform, where the resulting video is then manually scored using the free software package BORIS 24 . Also, in 2019, Singh and colleagues reported on a home‐cage monitoring system based on Raspberry Pi that fed video into a custom automated tracking system 25 .…”