Build a Blipper to Add Audio Markers to Your Videos

While the “YouTube personality” craze is baffling to a lot of us, there is one thing that even the most curmudgeony of us has to admit: those videos take a lot of work to make. Researching and recording a video obviously takes a lot of time, but even just editing can be a huge undertaking. During the editing phase, one of the most time-consuming tasks is simply tracking down key points in the video.

Evan Kale wanted a way to speed up the process, so he built Blipper. The concept is similar to a traditional clapperboard, but with the benefit of being unobtrusive so that Evan can use it himself at any time while he’s recording. Evan’s camera is a DSLR that has a stereo mic input, but his actual microphone is mono. By keeping the normal audio from the mic on the left channel, the right channel was free to use for markers.

The construction of the Blipper device itself is straightforward: when a button is pushed, voltage is applied to the right channel that feeds into the DSLR. That voltage creates a spike that’s clearly visible in the recording’s audio track. All Evan has to do is look for those spikes to find the portions of the video he wants marked, which he automated with a simple script.

The whole project ended up getting pricey for Evan, as he went through a couple revisions and had professional PCBs made. But, if you want to build your own you could do it for just a few dollars and a couple hours of work.