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View Full Version : OpenMAX IL 1.2 vs. 1.1.2: backwards compatibility status



fischman
08-07-2012, 09:10 PM
Is OMX-IL 1.2 meant to be backwards-compatible with 1.1.2 in any sense?
I ask because a short-lived attempt to make my app build against 1.2 headers was aborted when I realized some structs changed field placement silently. E.g. OMX_VIDEO_PORTDEFINITIONTYPE lost its cMIMEType field, making every other field move up sizeof(char*) bytes in the struct.

Is 1.2 not meant to be ABI-compatible w/ earlier versions of the spec? IOW, is building against the 1.2 headers while (runtime-)linking against the 1.1.2 libs not a goal?

tvu
08-14-2012, 01:25 AM
The 1.2 version is neither ABI compatible nor source code compatible with the 1.1.2. Due to the amount of feedback received on 1.1.2, it was unfortunatly not possible to answer all needs without breaking compatibility.

Modifications has been done trying to keep migration efforts low for both the components and the IL CLients. I would recommend using the 'Specification with changes marked' version of the specification to get a better view of the changes:
http://www.khronos.org/registry/omxil/specs/OpenMAX_IL_1_2_0_Specification_redline.pdf

Please also note the 1.2 specification is still a Provisional Specification, meaning some additional modifications may apply before the final release.