Fast forward to about two weeks ago and the big news was the Apple vs Adobe verbal fight about Flash. Adobe Flash has always been a CPU sucker on OSX, even for SD Flash video content and Apple made that point very clear. Then something mysterious happened. Very quietly, with zero fanfare, Apple posts Technical Note TN2267 carrying the title “Video Decode Acceleration Framework Reference”. Holy Cow, the elusive accelerated video decode API just popped into the open. This API is called VDADecoder and is available on Mac models equipped with the NVIDIA GeForce 9400M, GeForce 320M or GeForce GT 330M running OSX 10.6.3. Here’s a list of supported models:

• MacBook (Aluminum) shipped between October, 2008 and June, 2009.
• MacBooks shipped after January 21st, 2009.
• Mac Minis shipped after March 3rd, 2009.
• MacBook Pros shipped after October 14th, 2008.
• iMacs which shipped after the first quarter of 2009.

We are very happy to announce that Apple’s new API (VDADecoder) for exposing GPU accelerated H.264 decoding under OSX 10.6.3 is present and fully functional in svn (r29729 and above) trunk builds of XBMC for Mac, and will appear in the next stable version. Now, non-CrystalHD equipped XBMC for Mac users can enjoy the pure pleasure of accelerated H.264 decoding that was enjoyed by XBMC for Linux (VDPAU/VAAPI/CrystalHD) and XBMC for Windows (DXVA/CrystalHD) users. The VDADecoder API will handle all H.264 video content including that in m2ts containers. The last bit is very important as it means accelerated video decoding of decrypted Bluray m2ts files that are in H.264 format. Bluray can be one of three formats, VC1, MPEG-2 and H.264, with about 75 percent being in H.264 format. There is no word yet on accelerated VC1 decoding but since VDADecoder interfaces to low level Nvidia VP3 functions which can handle H.264 AND VC1/MPEG-2 content, we might see VC1/MPEG-2 support added to VDADecoder API at later date.

Also, while performance is fantastic with VDADecoder, there is still room for improvement. Running XBMC for Mac under Shark (Apple’s profiler) shows that about half of the CPU usage is now due to copying and converting the video frame from UYVY422 (VDADecoder’s native format) to YUV420P (XBMC’s internal format). Future work on the XBMC rendering path will allow passing decoded frames directly up to our renderer and thus skipping the copy/convert step. Stay tuned :)

The Dark Knight vc1 running at 1080p on an AppleTV

Through hard work and the joint efforts of several TeamXBMC/Redhat developers and the Broadcom Media PC Group, cross-platform hardware decoding of mpeg2, h.264 and VC1 video content up to 1080p will be coming to XBMC on OSX, Linux, and Windows via the Broadcom Crystal HD Hardware Decoder (BCM970012). The Broadcom Crystal HD is available now in a mini-PCIE card with ExpressCard and 1X PCIE form factors to follow. This means that the AppleTV and all those lovely new netbooks, Eee Boxes and older Intel Mac Minis have exciting new potential.

This solution has a common programming API, so many 3rd party developers and applications will be able to leverage hardware accelerated video content playback across OSX, Linux, and Windows platforms with minimal source code changes. Best of all, this is an open source solution with full source code for driver and library available for OSX and Linux under a GPL/LGPL license. Wow, this indeed is the Holy Grail and a major score for the open source community as this means no more tainted Linux kernels! Support has already been added to XBMC under the svn trunk. Our bleeding-edge users can expect to find the feature in the next nightly builds from our community builders, the more patient can wait until the next stable release. Other media projects such as FFmpeg, MythTV and Xine will soon follow as their developers add support.

The Windows driver binary, as well as the Linux source code for the driver and library can be found at the Broadcom web site. For OSX, the binaries and source code for the driver and library will be hosted at google code. Users in the USA can purchase the Crystal HD mini PCIE card from Logic Supply for $69 at the time of this posting, and of course there’s always ebay for those outside the USA.

XBMC for Mac is seeing some serious love these days. First up is a working IR remote under Snow Leopard (the crowd cheers). TeamXBMC is extremely grateful to Felix Schwarz (developer for Remote Buddy) for expanding his excellent driver framework and providing Candelair free to all. Candelair resolves the IR remote issues under Snow Leopard and is backward compatible to existing IR clients such has XBMCHelper. Candelair can be found here and is already compatible with the existing XBMCHelper IR client.

Not stopping at Candelair, Felix has also created an new HID remote class that resolves the need to fix up IR client when Apple changes the IR cookies. No more waiting for IR client fixes when Apple plays hide the cookies. Three cheers for Felix. The new HIDRemote class has already been integrated into XBMCHelper in our bleeding-edge builds and more detail about HIDRemote can be found here

Felix deserves a large round of applause for this effort and XBMC for Mac users should check out Remote Buddy for augmenting the capabilities of IR handling under OSX.

XBMC continues to work nicely on OSX and we foresee no problems regarding Snow Leopard for the forthcoming stable release.

First, Windows is really a goofy platform, it has almost no command-line tools that are of any use. Or where an interesting command-line tool does exist it does not work under WinXP and/or Vista. Diskpart is a good example, diskpart only knows about USB drive under Vista. And how long has WinXP been around? Stupid, just plain stupid.

In order to create a USB flash drive (patchstick) that will boot under the AppleTV, there are a few requirements.

1) The AppleTV boot.efi extracted from an AppleTV update DMG

2) GPT formated USB flash drive with two partitions, the first with a GUID of apple_recovery, the second can be any other format that has long file name support (ext2, fat32 or HFSplus).

3) A method to copy boot.efi into the first partition along with the required bits to boot the AppleTV.

4) A method to copy the selected plugins and packages to the second partition. This is where patchstick.sh and the payloads live.

Let’s take this one at a time;

1) This means mounting the DMG disk image under Windows. But Windows does not understand a DMG disk image. As a matter of fact, Windows does not understand any type disk image (what were they thinking). There are tools that one can install but I don’t want to install anything to a users Windows box. Fortunately, a few months ago, 7-Zip gained code to allow DMG extractions and what was a very difficult task became easy. You need the 4.59 alpha3 or better release. Extraction is a two step from the command line. The first step extract the actual hfsplus filesystem.The second step extracts boot.efi from the hfsplus filesystem.

7z e 2Z694-5428-3.dmg 2.hfs

7z e 2.hfs OSBoot\System\Library\CoreServices\boot.efi

2) Again, Window (WinXP-32) does not understand GPT disk format. WinXP 64bit and Vista say they do but knowing how Microsoft does things, good luck. There’s one software tool that cost $20 but that sort of defeats the purpose of open software. I originally thought I could just create a GPT format disk, sync GPT partitions to the MBR partitions and Windows would see the MBR defined partitions but noooo. You can boot Windows this way but not that’s not what I needed. The only free way to create a GPT formated USB flash drive under Windows is to pre-create a GPT format disk image and use DD.exe to clone it to the USB stick. DD.exe is also open source so life is good.

3) Injecting boot.efi into the first partiton. First partiton is HFSplus format with a different GUID. Again Windows gets in the way, it does not understand HFSplus and there are no free tools that do not require an install. Bummer. This stumped me for about a month until I realized the solution. The inject of boot.efi is solved by pre-crafting a HFSplus partition image with a zeroed boot.efi (must also be contiguous) in place. Knowing the byte offset of the dummy boot.efi file, I can use standard binary file i/o to replace it with the real boot.efi. This HFSplus partition image is then injected into the proper place of the GPT format disk image. Seems simple but this step took weeks to trying other methods before coming up with this idea.

4) The second partition can be fat32 (need long file name support). Because Windows has no support to mount a disk or partition image we have to get down and dirty. After many attempts using various libraries and even thinking about extracting fat32 support from OSX or Linux (ugh), I finally found some source code (and GPL too) that will let me copy a file from the Windows file system into a fat32 partition image. The code is not complete and directory creation is missing but I can side step that by pre-crafting the fat32 partition image to include the required directory paths. Then I just fill in the contents under atvusb-creator according to the user selection. Once the fat32 partition image is complete, then like the first partition, inject it into the proper place inside the GPT formated USB disk image. Then this disk image is overlaid onto the physical flash device using DD.exe.

All this sounds pretty simple now but has taken several months of dead ends, trial and failure and other yea—boo attempts. Now all the pieces are in place and I can proceed with linking it all together and getting atvusb-creator for the Windows platform into a testing then release status.

XBMC Launcher was one part of the puzzle, the other part was something that I’ve been working on and off for several months and that part was ATVUSB-Creator. This utility lets one easily create a USB flash drive of the special flavor that the AppleTV requires for USB booting. Couple that with ATV-Bootloader ( another creation of mine) and presto, a python/QT4 application that runs under OSX/Linux/Windows (only OSX right now) which is a GUI driven AppleTV patchstick creator. And 100 percent legal too.

The third part was enabling XBMC for Mac to run on OSX 10.4 as well as 10.5. This turned out to be pretty simple too because I am also an Apple Select Developer who has used XCode since the beginning of time. and Most of the time was spent getting the internal/external libs building correctly and documenting the build process.

So now you can enjoy XBMC for Mac on all three Apple flavors, 10.5, 10.4 and the AppleTV.

Installing XBMC for Mac is an easy three step operation;

1) Use ATVUSB-Creator to create a USB flash drive (remember to select XBMC for Mac)

2) Boot the AppleTV using this USB flash drive and it will automatically install the selected items

3) ReBoot the AppleTV and now there is an XBMC menu entry, select update and pick beta1 and let it install.

Select XBMC from the right hand menu, it will launch XBMC for Mac and enjoy.