Batch conversion saves slow QuickTime clips
Recently, I saw an advertisement for free high definiton (HD) video motion backgrounds (in full 1920x1080 HD resolution) from Footage Firm. After visiting the site, it turns out that “free” is a relative term—the free HD motion background DVDs are about $9 each, with “shipping and handling” charges.
Still, at that price, the backgrounds, with 25 different backgrounds per DVD, were a relative bargain ($15 to $40 per HD background is a more typical cost). Since my intended use for these backgrounds is in assorted home video projects, I wasn’t overly concerned about broadcast quality, and the demos on the site showed quality that was more than sufficient for my needs.
So I took a bit of a gamble, and ordered three of the “free” collections, for a total of 75 HD backgrounds in glorious 1920x1080 resolution. On first inspection, using Quick Look in the Finder, the backgrounds looked great, and well worth the money. When I opened the first one to play it, though, there was a problem: the frame rate was abysmal—anywhere from one to five frames per second (fps), where 30fps would be considered ideal.
Just to make sure it wasn’t an anomaly on one Mac, I tried it on four different machines, running both OS X 10.5 and 10.6. I had similar horrid results on all four machines. I even tried looking at them in Windows 7 via Fusion 3, but things weren’t much better there. At these low frame rates, the backgrounds were unusable, and I thought I might be out my $25 investment.
Then I looked at the Movie Inspector window (Command-I in QuickTime Player), and was surprised to see the format listed as JPEG 2000. I’d never heard of JPEG 2000 being used for video, and wondered if the format was causing my playback speed problems.
As a test, I used QuickTime Pro (a $30 upgrade that enables more features in QuickTime Player) to export one of the movies to a new file, switching from JPEG 2000 compression to Animation, a very high quality alternative. The result? The modified file played back perfectly at 30fps. Unfortunately, the file was also quite large—the exported file was nearly triple the size of the original.
On the advice of a friend in the video business, I tried again, but used Photo JPEG as the compression format. The results here were much better: The frame rate was 30fps with no perceptible differences from the original, at less than double the file size. As a brief demonstration, this movie shows an original background on the left, and the converted version on the right:
I’m sure there are many other video formats that could have been used with similar good results, including H.264. However, I didn’t want to spend too much time on this project, so I just went with Photo JPEG after seeing the good output of my test conversion.
Batch conversion options
So now I knew my investment wasn’t wasted, but I had 74 more backgrounds that needed converting. While I could do them one at a time in QuickTime Player, at several minutes per conversion, that didn’t strike me as a good use of my time.
I then remembered that I own an older version of Final Cut Studio, which, then as now, includes the Compressor batch processing application. After installing a few software updates to bring Compressor up to date, I was able to set up a batch job that made short (physical) work of the conversion process. It still took a few hours for my Mac Pro to work through all 75 backgrounds, but when Compressor was done, I had 75 30fps 1920x10280 HD video backgrounds.
But what if you don’t own Compressor? Are there any cheaper or free alternatives that will allow batch conversion? After inquiring via Twitter, I wound up with two programs that allow batch conversion of QuickTime video files.
The first is Roxio’s $50 Popcorn, which includes batch conversions amongst its many features. However, if all you want to do is batch convert a bunch of videos from one format to another, Popcorn may be overkill. Its batch conversion feature worked well, though it took some time to populate the file list, as Popcorn created previews of each video I added to the list.
The second alternative is MPEG Streamclip, a free program that handles video conversion and more. As a test, I reconverted my backgrounds using MPEG Streamclip, and the process worked perfectly. After launching the program, select List -> Batch List, or press Command-B to open the Batch List window. Click the Add Files button, use Shift and/or Command to select multiple video files from your source folder, then click Open.
This will open a new window in which you specify the task you’d like to perform on all the files; select Export to QuickTime, click OK, and then specify a save location in the dialog that appears.
Finally, click Select to close the save dialog and open the Movie Exporter window. It’s here where you’ll specify the conversion to be applied to all your clips.
There are a ton of settings here, but I got good results by simply setting the compression (I used Apple Photo - JPEG), quality (I set it to 100%), and frame size (I left it at 1920x1080, the size of the originals).
Once everything is set, click To Batch, and the selected files will appear in the Batch List window. Click Go, and then just wait. When the program’s done, you’ll find your converted videos in the destination specified. Because MPEG Streamclip provides access to the same QuickTime compression options as you get with QuickTime Pro or Compressor, the end results should be identical to what you’d get using those programs.
If you ever find yourself with what seems to be an unusable collection of video clips, you might try running them through a batch converter instead of just dropping them in the trash—I was able to salvage what I originally thought might have been a waste of money.
[Rob Griffiths is a Macworld senior editor.]