Microsoft Expands exFAT Multimedia Licensing

alphadogg writes "Microsoft Thursday announced a broadening of its licensing program around its exFAT file system, which is designed to handle large multimedia files. Microsoft hopes companies making devices such as cameras and smartphones will adopt the Extended File Allocation Table (exFAT) technology to support the sharing of audio and video files. The technology is available on Windows 7, Vista SP1, Windows Server 2008 and Windows Embedded CE."

Comments

Re:I smell DRM

[Stormwatch]

Are you serious? I wonder, have you ever heard of:

* The AARD code?
* OOXML?
* The Halloween documents?
* Embrace, extend and extinguish?
* Samizdat?

"Have some faith", you say? Indeed, to trust Microsoft to act ethically is a matter of faith: to believe in something incredible against all evidence.

Re:Microsoft and Making Money

[Tapewolf]

What exactly is evil? Firstly, they haven't created a standard. If they had then surely they would have published the specifications somewhere. exFAT is a proprietry file format.

I don't know if they expect everyone to use it, although they may hope that everyone uses it.

Everything that wants to SDXC will have to use exFAT. It's part of that standard. This is going to be inconvenient for anyone who wants to use their shiny new camera/camcorder on a Mac or linux netbook or someone else's XP machine.

Re:Just great...

[TheRaven64]

It's still a FAT variant, which means that seeking in a file is an O(n) operation (it's O(log(n)) on most systems) in terms of the size of the file. They've added a free space bitmap, but creating and appending to a file is still O(n) in terms of the size of the disk, just with a smaller constant. Both the FAT and the free space bitmap need to be kept in RAM for reasonable performance. The FAT size depends on the disk size and the configuration, but a typical 32GB memory card will need 32MB for the FAT. This is a lot of memory for a mobile device. Something like the N900 has 32GB of Flash and only 256MB of RAM. You're using an eighth of the RAM just for the FAT. More if you add another memory card, and that's not counting the free space bitmap (also needs to be in RAM, but is quite a bit smaller), ACL or file caches or any other driver overhead.

Oh, and the FAT itself needs to have individual words updated in a large contiguous section, which is about the slowest operation possible for Flash. They could improve this by using -1 instead of 0 to indicate free sectors: then allocating a sector would not require erasing a flash sector, but deallocating would.