The Animal Cage Camera (ACC) operates with our Videoarchiver software to provide video that is synchronous with the data acquisition computer clock to within ±50 ms. The ACC is a Power-over-Ethernet (PoE) device that requires only one network cable connection to a PoE switch for power and communication. We place the ACC in a Faraday enclosure, connect it with a shielded network cable to to an network feedthrough at the wall of the enclosure, and then with a shielded or unshielded network cable to a PoE switch. (Exception: cameras S0205-S0215 require an unshielded cable from the enclosure to the switch.) We connect this switch to our data acquisition computer, and so allow the data acquisition computer to download video from the camera.
The Neuroplayer program makes sure that telemetry recordings are synchronized to ±50 ms with the data acquisition computer clock. Assuming we have both the Videoarchiver and Neuroplayer running on the same computer, the result is synchronization of telemetry and video to within ±100 ms.
Our lamp scheduling program allows us to turn on and off the infrared and white lights on a twenty-four hour cycle of our choosing.
When commercial CCTV camera systems record continuous video, they produce a sequence of files on our data acquisition computer, each of which is supposed to span a specified length of time. When we view these files, we find that the length of time spanned by each file is a few seconds longer or shorter than specified. Each file has a name that gives its time of creation, and the difference in creation time from one file to the next differs by a few seconds from length of the video contained in each file. When we start viewing a new file recorded by a CCTV system, we must wait a few seconds before the picture establishes itself. As a result of these problems, we cannot rely upon synchronization between video produced by such systems and recordings obtained form our subcutaneous transmitter system. In practice the two chronologies disagree by tens of seconds, and in a manner that we cannot predict or correct for. Our Animal Cage Camera (ACC) is designed to solve these synchronization and viewing problems, and provide superb image quality in both light and darkness.
We connect ACCs to a PoE switch, along with our data acquisition computer and our telemetry server. In the diagram below, we see an example of how ACCs and a telemetry system can be set up to operate together.
The ACC provides video that is synchronous with our subcutaneous transmitter recordings to within ±100 ms over any recording duration. The camera streams its video as separate frames at a fixed rate. These are received by the Videoarchiver process on the video recording computer, where they are assembled and compressed into a video that is synchronous with the local computer clock. Given that the EEG recorded by our subcutaneous transmitters is also synchronized to the local computer clock, the result is EEG and video synchronized to the same clock within a twentieth of a second. In the Neuroplayer Tool, we specify a directory containing the video files, as well as a directory containing the EEG recording files, we can navigate through the EEG recordings and see the synchronous video displayed automatically.
|A3034C||Sits on floor, mounts in mobile phone camera stand, or zip-ties to
shelf structure. Provides 12 white and 12 infrared LEDs.
|IMX219||DSL227||820 × 616, 20 fps, H264 crf=23 (HR)
410 × 308, 30 fps, H264 crf=15 (LR)
|A3034D||Sits on floor, mounts in mobile phone camera stand, or zip-ties to
shelf structure. Provides 12 white and 12 infrared LEDs.
|IMX219||DSL215||820 × 616, 20 fps, H264 crf=23 (HR)
410 × 308, 30 fps, H264 crf=15 (LR)
The image quality we obtain from the ACC is superior to that of low-cost CCTV systems. The ACC lens's depth of field and sharpness of focus, and the superb exposure compensation of its image sensor, provide clear, sharp images of laboratory animals in poorly-lit cages, even when the camera is only ten centimeters from the cage wall or ceiling. By default, we ship the ACC with focal range 40 cm and depth of field 20 cm to infinity. We can adjust the focus for closer or farther viewing by loosening two screws on either side of the lens, rotating the lens, and tightening the screws again.
The ACC provides both white and infrared illumination that we can use to enhance image contrast, take pictures at night, or generate twenty-four hour illumination cycles. In order to view animals at night in infrared light, our lenses must not include an infrared-blocking filter. Without an infrared-blocking (NoIR) filter, the colors we record will be affected by infrared light from any source. The standard ACC does a poor job of recording colors in sunlight, or when its infrared lights mixes with ambient white light. We recommend operating the ACC in white LED or flourescent lighting during the day, and infrared at night. The Videoarchiver's scheduler program allows us to set up twenty-four hour programs of alternating white and infrared illumination.
One use of video recordings is to track the movements of individual animals. Given that animals tend to remain in one piece as they move around, and rodents tend to remain the same color, we can treat animals as blobs in image analysis, and track them with video blob tracking algorithms. But when we have more than one animal in a cage, and the animals are near-identical in appearance, and keep vanishing underneath obstacles, and grouping together into larger blobs, video blob tracking cannot distinguish between the animals. But if we have subcutaneous transmitters implanted in our animals, we can use an Animal Location Tracker (ALT) to measure the approximate movements of each animal, compare these movements to those of the blobs produced by blob tracking, and so determine which blob corresponds to which transmitter, which results in unique identification of each blob. We call this disambiguation of the blob tracking by the ALT data. This disambiguation is possible only because the ACC videos are so well-synchronized with the subcutaneous transmitter system, and in particular the ALT's recordings of pick-up coil power reception.
We sell the ACC for US$1000 each, with no volume discount. If you can tolerate ±10 s synchronization between telemetry and video, we suggest you instead use Telemetry-Compatible Webcams (TCW). The TCW is a power-over-ethernet (PoE) webcam that we buy on the consumer market. We first test them with our telemetry system to make sure they do not disturb signal reception, and we equip them with the correct cables for integration into our recording system. We sell our TCWs for only $200 each. We recommend you do not purchase webcams yourself for use with our telemetry system. The power converters used in PoE cameras, regardless of their cost, can generate so much noise that they interfere with telemetry reception. You may find that you lose telemetry reception whenever you turn on the camera's infrared lights.
Animal Cage Camera (A3034): A high-resolution, power-over-ethernet camera with remote-controlled white and infrared illumination. Synchronization of video and telemetry within ±100 ms..
Telemetry Compatible Webcam (TCW): An inexpensive power-over-ethernet camera with infrared illumination that does not interfere with our telemetry system. Synchronization of video and telemetry within ±60 s.
Videoarchiver Tool: Manual for the Videoarchiver, a LWDAQ Tool, which records video from multiple ACCs in such a way that it may be played back synchronously with EEG and ALT recordings.
Neuroplayer Tool: Manual for the Neuroplayer, a LWDAQ Tool that plays simultaneous video recorded from ACCs, biometric signals recorded from subcutaneous transmitters (SCTs), and activity monitoring recorded by animal location trackers (ALTs).
Videoarchiver Libraries: Archive of libraries for MacOS, Linux, and Windows necessary to run the Videoarchiver in LWDAQ. Download, decompress, and place the Videoarchiver folder next to your LWDAQ folder.
Real-Time System Setup: Watch us put together a telemetry and video recording system in five minutes.
Animal Location Tracker (ALT): A platform of radio-frequency pick-up coils that measures the movement of individual subcutaneous transmitters in a cage above.
Test_21AUG20.zip: Fifty-five 20-s videos with accompanying telemetry from two transmitters mounted on mouse toys.
Test_13JUN19.zip: Four 600-s videos with accompanying telemetry from an animal with an Implantable Sensor with Lamp (ISL). We see the light flashing, and unwanted lamp artifact in the recorded EEG signal, which is perfect for checking synchronization of video.
Test_05JUN18.zip: Ten 60-s videos with accompanying telemetry from four transmitters being handled in a Faraday enclosure.
Video Blob Tracking (VBT): A description of how we analyze video frames to obtain the coordinates of animal-like objects. This link leads to our GitHub repository, where we keep the developing software files.
Parts and Prices: A list of devices and their prices in various quantities.
Drawings: Drawings of the camera enclosure's metal components.