RichMedia annotations allow one to embed arbitrary media formats in PDF documents. It's up to the PDF viewer to decide whether and how to play that format.
In the case of the PDFNet SDK for Android, MP4 video is extracted and played by the operating system.
In the case of Acrobat, only Flash is supported. Acrobat plays videos using a video player written in Flash and embedded in the PDF --- VideoPlayer.swf. Since VideoPlayer.swf is not PDFTron's property, we cannot embed it when creating RichMedia annotations.
There do appear to be alternative implementations available for licensing:
[ Please note that we are not affiliated with the above, that we have not tried any of these alternative players out, and that we therefore cannot provide a recommendation regarding their use.
Please note also that Acrobat is not our product and we can provide only very limited advice regarding getting it to play arbitrary video formats. ]