My copy of Sorenson Squeeze 4.3 suite arrived the other day and after about 4 minutes with the online help materials I got down to work transcoding samples of the PBS videos we’ll be using in our upcoming streaming project. The videos were delivered by PBS as mp4 files–weighing in at about 800-900 megabytes per one hour episode. My earlier attempts at transcoding with QuickTime Pro reduced the file size but I wasn’t at all happy with the quality of the streams (too many artifacts, dropped frames, etc.). Where QT Pro provides the Sorenson Video 3 Codec, with the Squeeze suite the codec is bumped up to Sorenson Video 3 Pro. What a difference better software makes!
Squeeze 4.3 offers several different codecs (MP4, QuickTime, RealMedia, Flash, WMV (need plugin)) and a number of filters and tweakable options, all pretty simple to use (even if you don’t quite understand the outcome of certain switches and checkboxes). Here’s a sample from one program, encoded in QuickTime (using Sorenson Video 3 Pro codec) with streaming “hints†at a 512K bit rate. I tested this version last nite over my WiMax connection in rural Virginia and it streamed quite nicely–looking no different really than the version I ran off my local drive.
[Note: You’ll need QuickTime to view these samples]
QuickTime 512K data rate (384 video, 128 audio), Dual Pass VBR, 480 x 360
I made a second version with the same settings, only a smaller video window (320 x 240) and the quality is better (in web-based video, good things really do come in smaller packages).
QuickTime 512K data rate (384K video, 128K audio), Dual Pass VBR, 320×240
Using this 320×240 window, the 875 Mb mp4 video compressed to a 178Mb hinted streaming version.
Here’s a final version, created using Sorenson’s H.264 codec (Sorenson AVC Pro). It seems I had to run this through QuickTime Pro (export->Movie->Hinted Movie) to get it to stream correctly but this might be because I had some other setting incorrect…nope, that’s just the way the AVC codec works with QTSS.
MP4 (H.264) 512K data rate, single pass encoding, 320×240
and a slightly different clip with a larger window size and 2 pass encoding:
MP4 (H.264) 512K data rate, 2 pass encoding, 480×360
I also created a version using the Spark Pro Flash codec included with Squeeze and that too looked quite clear. Unfortunately, as I write this I have not yet installed the Flash Media Server (free developer edition) so I can’t yet see how it streams. Squeeze 4.3 provides the Spark Pro codec but also offers support for the add-on On2 VP6 Pro codec plugin(which must be purchased separately). I tried out the “trial†version of the On2 plugin that comes with Squeeze 4 suite and despite the little “On2 VP6†watermark that obscured portions of the output, it is a demonstrably better codec.
Another really useful feature Squeeze offers is a “watch” folder—drop a file (or files) into this folder and they get processed automagically—great for overnight batch processing. On a dual 2.3Ghz PowerMac it takes around two hours to transcode a one hour mp4 video (and pegs each CPU at about 90% utilization while it works). I’m sure I could make a few choices during setup to reduce those numbers (for example, the work I’ve done so far used 2 pass encoding which yields a better picture at the cost of more processing), but when run overnight, do I really care how long it takes?
Research (experimenting and learning) continues. I hope to set up a developer edition of Adobe’s (nee Macromedia) Flash Media Server in the next few days and find out whether all the “buzz” around that platform is justified.