I'm trying to encrypt arbitrary content using the PlayReady envelope format, in order to send it to a 3rd party app which supports that format.
I was not able to find the format specification online. Does anybody know where I can find the spec, or is it supported only by opaque services provided by Microsoft?
You will find the PlayReady Envelope format specified in the Microsoft PlayReady Documentation Pack (available to Microsoft PlayReady technology licensees). The relevant section is Specifications -> Microsoft PlayReady Format Specification -> 3. Envelope File Format
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