The dual camera bird box build started off back in 2016, and has been live since the 2017 Spring nesting season. It was my second Raspberry Pi-based birdbox, and my first attempt to combine a Raspberry pi camera module with a USB webcam on the same Raspberry pi mini-computer. The system has video motion-capture, day + night illumination modes, an entrance hole activity logging mechanism, and also monitors temperature (?why not)...
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Nearly fledging: My favourite picture of the 2019 season
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This year (2019) is its first successful nesting season, seven great tit chicks fledged a few weeks ago, with another pair currently sitting on five eggs. I've had some requests on the Twitter about his box so this is an attempt to describe some of the modifications I've made over the last few years to fix various issues, and share some of the stuff I've learned along the way.
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| That's a 32mm entrance hole |
The Cameras
Camera 1 (SIDE): This is a Microsoft LifeCam Cinema usb webcam. It can only see in visible light - I used one of these in my first birdbox (side-view-box, 2016). A motion-jpeg (mjpeg) network video stream from this webcam is picked up by a remote PC running iCatcher CCTV software. iCatcher isn't able to include audio from this source.
Camera 2 (TOP): This is a Raspberry Pi v2 Infra-Red (IR) camera positioned above the nest space. An IR-cut module sits between the camera and the main nesting chamber and switches it between IR (night/dark) and visible light sensitivity (day/lit) . A motion capture application called pikrellcam uses this camera, with the videos saved directly to the same networked PC mentioned above. Camera-1 (the webcam) has a handy built-in microphone that pikrellcam cleverly uses, adding sound to the captured video from camera 2.
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| Camera 1 (Side) fits into height-adjustable slots. Entrance hole is on the Left of this pic |
The entrance hole has two IR beams that once broken record the event to a file. Based on the order of breaking it's possible to work out whether the bird is coming or going. I added a visual indicator to check this is working, the video below shows the outer then inner beams being triggered whilst I balance precariously up a ladder...
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| Yes, I know the wiring is a mess... |
The side camera can be reviewed directly via iCatcher console on a remote PC, or via a webpage using any network connected device. Exporting video / screengrabs from iCatcher is a pain in the proverbials.
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| iCatcher Console with Camera-1 as source (USB webcam. Visible light only. No audio) |
The top camera (Raspberry Pi cam) can be reviewed in a web browser on any network-connected device. Exporting video / images is really easy and can be downloaded directly via a web browser.
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| Pikrellcam with Camera-2 as source (Raspberry Pi v2 IR camera+IR cut (day mode)_white LEDs on. WITH Audio |
Design evolution, 2017 to now (May 2019)
2017: The Bird Box went up in April. No birds came in all year with just the occasional wasp and spider triggering video capture (pikrellcam). The entrance hole had logged some attempts that were probably birds popping a head in, so assuming that the hole was too small, I enlarged it from 20mm to 32mm over the Winter. This wasn't as simple as just drilling the hole bigger as the entrance hole IR activity detector beams needed moving to accommodate a bigger hole. The 'glass partition' between the side camera and the main nesting chamber kept getting dusty and it also created an annoying reflection of the side camera (which could essentially 'see itself'), so I replaced it for a half height plywood partition that the camera could see over, giving it an unimpeded view into the box, as well as allowing its microphone do a better job.
This box did do some useful work that season - Using a programme called ffmpeg, I used it to transcode a video feed from a separate, less-powerful Raspberry pi/usb webcam combo on a Robin nest and live-stream the result to YouTube.
2018: The enlarged entrance hole meant birds were coming in periodically, probably looking for food. The default lighting remained on 'night mode' (just infra-red) as I thought the birds would be put off by the visible light LEDs. I also hadn't got round to making the day-night switching happen automatically.
By April we had a pair of great tits bringing in moss. I had the 'bright' idea of making the white leds come on when movement was detected by pikrellcam software to improve the daylight video capture... bad idea. What I actually ended up with was a system that kept switching from night to day mode whenever a bird came in. I think that the 'thunk' of the IR cut module switching between modes freaked them out so they nested in a neighbour's box instead. That was the end of Spring 2018 nesting.
THIS YEAR.. 2019: A great tit pair started making visits from early March this year. Nest building started 10 March, nine eggs laid and eight hatched on approx 17 April. The last one fledged two weeks ago 7:50am on Sunday 5th May. Unfortunately I missed them hatching as the PC where the videos are saved had crashed and I was away on holiday.
I also got around to fixing the day/night transition as described in this post, so lights come on at sunrise and off at dusk (switch to IR mode).
A selection of images / videos from nesting session 1
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| Cropped-in still image from camera 2. Lighting aided by south-facing window on RHS of this image |
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| Feeding False Black Widow Spider |
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| Difficulty swallowing another false black widow spider |
The next image is a screen-grab from a top camera video. These are really easy to make using vlc media player.
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| An explosion of Great Tits |
This is the male on the day the last chick fledged. He's looking a bit battered
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| Scruffy male adult after the chicks all fledged |
So... I though that was it for this season, which was timely as we were just about running out of disk space on the PC that stores the captured video. I removed the remains of the deceased chick, and in the process broke the night illumination mode...
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| This one didn't make it :( |
Daylight-sensitivity / video quality from the top down camera had dropped considerably over the previous year. With no physical partition, the chicks were able to have a lovely time jumping up and down and pooing on the the side camera too.......Leaving a 'poo-obscured cam in the day, cant see anything at night' bird box.
Surprise 2nd nesting
...But 5 days later, another Great tit pair have moved in (Fri 17 May) and re-built the nest. I've never had two back to back nests in the same box before.
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| And who miss, are you? this is the second female re-building the nest |
Top camera modifications... New Daylight LEDs / IR cut replacement
The Raspberry pi camera has poor low light sensitivity so I wanted to improve the lighting. I swopped some of the existing 5mm LEDs for some LED panels from Pimoroni- I've used these in four other bird boxes I built this year see here. They give a nice even illumination, avoiding the spotlight effect you get with 5mm LEDs. You can see my original attempt to avoid spotlighting with the original 5mm leds by pointing them up towards a white background, but they don't really make enough light for the Raspberry Pi camera which has fairly awful low light sensitivity which isn't surprising given that its lens aperture is a couple of mm.
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| New LED panels on underside of top section |
I also swopped the IR cut for a new one (see this post) as the old one had fogged up.
2019 2nd nesting, updated performance...
Our five eggs have yet to hatch, the image quality is much better:
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| Cropped down to show detail. I like the symmetry in this one |
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| Female number two turning in for the night |
Male number 1 was looking very shabby at the end of the the last nesting session.
This clip shows make number 2 feeding female number 2 while she's incubating her five eggs, he's not scruffy, so Ithink that he's a different bird. Can't say much about her though.
More to come... when this lot hatch
Those led panels really help to create excellent video quality. Well done mate!
ReplyDeleteThanks Steve, they are definitely the essential bit of kit for the season, with the advantage of costing about the same as a Mars bar each
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