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THRESHE
Apr 10, 2008, 10:11 AM
Hi everybody!
I'm pleased to join your community and I hope that I'll be able to help others.

Recently I had a task to port a DRM codec from Windows to Mac OS X. This codec isn't a complicated one it just decrypts a file using a key and XOR function. I've started reading QuickTime docs and I've found out that I should create a component. But there are so many types that I don't know which one I should pick for my purpose :confused: Should it be a "Data Handler component" or a "Media Handler component" or some mysterious "Channel component"(I didn't find any docs about it...) ?

Please give me some advice ;)



wrldwzrd89
Apr 10, 2008, 10:21 AM
After looking through the QuickTime docs for developers, it looks like a media handler component is what you need. According to the documentation:

Each media handler is primarily responsible for understanding the format and content of the media type it supports. The media handler is intimately familiar with the sample structure used in its media, the compression techniques used to store the media’s sample data, and the performance characteristics of the device that stores the media.
Link (http://developer.apple.com/documentation/QuickTime/RM/WritingQTComponents/MHCreating/B-Chapter/chapter_3_section_2.html#//apple_ref/doc/uid/TP40000898-AboutQuickTimeMediaHandlerComponents-DontLinkElementID_4)

THRESHE
Apr 10, 2008, 10:41 AM
The problem is that my codec should decrypt data and send it to another codec (for instance H.264) which will handle the data and display video.

kainjow
Apr 10, 2008, 03:55 PM
I'd suggest posting your question on the QuickTime API (http://lists.apple.com/mailman/listinfo/quicktime-api) mailing list. Whenever I have a tough question I usually go to the mailing lists.

THRESHE
Apr 12, 2008, 07:50 AM
I'd suggest posting your question on the QuickTime API (http://lists.apple.com/mailman/listinfo/quicktime-api) mailing list. Whenever I have a tough question I usually go to the mailing lists.
Thanks a lot for your reply. It took me about 5 minutes on this mailing list to find a link to this document (http://developer.apple.com/technotes/tn/tn2038.html) which shows the way to resolve my problem. So it can be either Data Handler component or Media Handler component. It's odd though that i didn't google it before...
Anyway thanks for your advice again ;)