Create a Waveform Image with ffmpeg
Waveform images have a variety of uses and I've started seeing waveform images overlaying at the bottom of videos.  That type of feature seems useful if you want to see identify music in a video or specific spaces in a video which feature action.  If you're creating an audio-centric app, you may have a dozen uses for the waveform image.
You can easily create a waveform image using the amazing ffmpeg utility with a very short command:
ffmpeg -i input -filter_complex "showwavespic=s=640x120" -frames:v 1 output.png
The image you'll get back will look similar to:

There are a variety of customizations you can create for waveform image as detailed in the ffmpeg waveform documentation.  Take some time to experiment with all of the features provided by ffmpeg -- you can do amazing things with media!
![9 Mind-Blowing Canvas Demos]() - The - <canvas>element has been a revelation for the visual experts among our ranks.  Canvas provides the means for incredible and efficient animations with the added bonus of no Flash; these developers can flash their awesome JavaScript skills instead.  Here are nine unbelievable canvas demos that...
 
![Chris Coyier’s Favorite CodePen Demos]() - David asked me if I'd be up for a guest post picking out some of my favorite Pens from CodePen. A daunting task! There are so many! I managed to pick a few though that have blown me away over the past few months. If you... 
![JavaScript Canvas Image Conversion]() - At last week's Mozilla WebDev Offsite, we all spent half of the last day hacking on our future Mozilla Marketplace app.  One mobile app that recently got a lot of attention was Instagram, which sold to Facebook for the bat shit crazy price of one... 
![Build a Slick and Simple MooTools Accordion]() - Last week I covered a smooth, subtle MooTools effect called Kwicks.  Another great MooTools creation is the Accordion, which acts like...wait for it...an accordion!  Now I've never been a huge Weird Al fan so this is as close to playing an accordion as... 
How do you get a transparent background?
Is it possible to build waveform image using
offlineAudioContext? Seems like the exact tool for the job.