Thoughts and Ramblings

Well, I have had reason with my research to do some Java development. No biggie, Xcode supports Java too, right? Wrong! well mostly. This all came to a head when I downloaded the latest beta of Xcode (which I am only using because these fix a serious performance issue with the non-beta releases). After the last download, I found 4 distinct bugs in 2 hours, and I’m still finding them. Two of these are Java related, so I gave up, and looked for alternatives.

Well, I got to fiddling around with the existing passthrough on the AppleTV. I found where it works, and where it doesn’t. AC3 passthrough does work in .mov files with 48KHz files, of any bit rate. I did this with importing a .ac3 file into .mov, and adding a video track (ATV doesn’t like playing audio only files). I still need to test 44.1KHz, and 32KHz, but they are a bit harder to find. I have still to come across one of them.

I have seen a few people post methods about enabling AC3 passthrough, and many of them are overly complicated or in some cases even wrong. This also serves as the first place to describe how to enable DTS passthrough. Since I designed the code that actually does this, I’ll list the steps here:
Note: This does not work with all receivers. If these instructions fail for you, most likely your receiver will not work with this. Passthrough is still a hack, and thus this hack is still outside of the specs.
Note 2: Apple broke AC3 rather seriously in QT 7.3 (bug id 5594478, go tell them to fix it). If have a .mov file, open it, and it says that it is stereo audio rather than 5.1, this is a symptom of that bug. You will need to have at least Perian 1.1 and re-open the original file that made the .mov file. This bug has been fixed in 7.4.5, but any .mov files created with QT 7.3 or 7.4 are still affected by this bug.
Note 3: Perian 1.1.4 contains a bug in which DTS passthrough fails to work. This will be fixed in the next version. This has been fixed in Perian 1.2, released Dec 17, 2009.