67 Days of Spring

Earlier I used my Wingscapes PlantCam for several shorter time lapse projects. In this posting I present a two-month time lapse, from mid-March to mid-May, with the camera aimed into the woods in back of our house. You'll see daffodils bobbing up and down, a brief snowfall, and the greening of the woods from bottom to top (the forest floor always greens up first, and the tall trees leaf out last). When the weather switches from cloudy to sunny, there's a flash of light and moving shadows! Also, at around the 57 second mark, the invasive bush honeysuckle in the middle of the frame gets chopped down, giving you a better view into the woods beyond.

Now, some details. The camera took a picture every 30 minutes between 10AM and 3PM each day. Once I downloaded the photos and began constructing a video, I saw that the images whipped by much too fast; it would have been preferable to take a picture every 15 or even 10 minutes. Not willing to wait and try again in 2012, I used the interpolation techniques from the ZoomWalks to add intermediate frames. I also continued my research into encoding with ffmpeg, particularly with the complex (daunting) h264 encoder (the preferred format by most video hosting sites). After some Googling and experimentation, I created the video you saw with this command:

ffmpeg -f image2 -i ffr-%05d.jpg -vcodec libx264 -vpre hq -crf 24 -g 320 -threads 0 video-d.mp4

The file created this way was only 47MB, compared to 152MB using the original technique. It downloads much faster, but makes the computer CPU work a little harder to play the video. I hope I've achieved a good tradeoff. Note that you can always toggle between HD, high definition, and SD, standard definition, by clicking on the blue HD symbol on the playback bar. The default is HD playback.

PlantCam Timelapse with Clivia and Snowfall

In addition to a couple of books, at Christmas time I received a PlantCam, a time-lapse camera from the same outfit that makes the motion-sensitive BirdCam that we've used for the last couple of years. You've seen some pictures from that unit, including this post. With this blog entry I will subject you to my first time-lapse "compositions." No doubt there will be a learning curve.

Note: the YouTube clips default to a 360p setting, at least for me, but the original material is 480 pixels high. The clips will look much crisper if you go to the 360p that shows up on the right side of the YouTube playback controls and click to change it to 480p. Unfortunately, the clickable 360p shows up only after playback begins! If I ever find a way around this ugliness, I will update this post.

My first subject was a large, nay, huge clivia that grows near our first-floor bay window. In late December Clivia (that's her proper name) starting pushing up a stalk, and I set the PlantCam to take a frame once every 5 minutes, with this clip recording from December 31st to January 17th.

As you can see, the camera position with regard to the sun was poor, causing washout and flaring. (I threw out the worst of the glare-burned frames.)  But it did reveal that Clivia does a lot of growing at night, of which there is a surplus at year's end, with the first frame of each new day showing a jump in the stalk.

The next clip is of the snowfall -- well, the first part of it -- of January 20th. The camera was positioned on a tripod in a protected corner of the front porch, and set to grab one frame per minute. After a while the snow starts to accumulate on the street, and then the snow on the bushes in the immediate foreground piles up. You will notice that I changed the PlantCam setting so that it no longer smacked an intrusive imprint  across the bottom of the frame; instead I wrote a script using ImageMagick, an open-source tool, to create a watermark in the lower left corner with the date and time.

Technical note: the date and time were extracted from each frame of the clip, specifically, from the EXIF data that every modern digital camera includes in a JPEG file. I don't use the PlantCam's ability to create the movie within the camera; first, I would rather have the opportunity to process each frame, as with the watermark, and second, the PlantCam's automatic movie generation cannot handle a large number of frames. I again used an open-source tool, ffmpeg, to generate a movie from the many still images.

The final and best clip is of the very sunny day after the snowfall. The light and shadows make this clip, recorded at one frame every 30 seconds, great fun to watch. Yours truly is one of the early shovelers.

I'll continue to experiment with the PlantCam, and come spring and summer, there will be plenty of daylight.