So you think you're a videographer…
I thought I knew all I needed to know about compressing movies. CD-ROM, DVD-video, online streaming? No problem. Then about a month ago I bought a digital frame (15" Living Images) from Digital Frames Direct (DFD) in order to show some short films at an upcoming exhibition, and I ran into problems.
I'm a Mac user and use Final Cut Pro (FCP) for editing. FCP can export any type of movie I like, using whichever codec (compression-decompression format) that seems appropriate. My new digital frame is supposed to display videos in "either the mpeg 1,2,4 format or AVI/divx format" according to DFD's short (seven-sentence) document "Converting videos". A doddle, I thought.
After hours of exporting batches of test movies from FCP and trying them out on the digital frame I started to wonder whether it could indeed display movies in any shape or form.
Back to DFD's "Converting videos" document:
"You can use many programmes but one of the easiest and the one we used is Xilisoft which you can download here."
Normally I only use my Dell laptop for checking that my projects work the same on a PC as they do on my Mac, but I downloaded the free version of Xilisoft's video converter to my PC laptop out of curiosity. The only limit to the free version is that movies can't exceed 3 minutes, but as the movies I was hoping to exhibit were "one-minute wonders" I could give it a go.
The first test movies I exported using Xilisoft's video converter wouldn't play on the digital frame. Then I had a wee epiphany. I'd been exporting movies at a size of 1024x768 pixels, the supposed resolution of the digital frame, and at 768x576 pixels, thinking that datarate might have been the problem. But what if the frame was using oblong pixels like a TV screen rather than the square pixels you get on a computer monitor? Was it expecting DV-footage resolution?
I tried Xilisoft's standard MP4 codec at 720x576 pixels but with its aspect ratio set to 4:3. Lo and behold, a format that the digital frame can display. Not only that, but by tweaking the datarate to "3500 kbits/s" in the program I ended up with a quite acceptable result playing back at around 2525 kbits/s.
And here's a preview of my "one-minute wonders" series: