Using VDPAU correctly means checking for preemption and possibly regenerating the context all the time. With the current API there is no context or other user-defined pointer and thus this in not possible during decoding unless using some hack like global variables. The need to reinitialize both surfaces and even function pointers makes handling preemption even more difficult. This patch introduces a new render2 function that gets both the AVCodecContext and AVFrame in addition, in both the user can store additional opaque data. This allows even advanced approaches like keeping a "generation counter" for the surfaces so they can be regenerated on the fly and efficiently. In addition, the function has a return value that will be passed through all the way instead of being silently ignored as for the current render function. Unfortunately the HWAccel API has no way of providing API/ABI compatibility, so a currently disallowed state (render pointer being NULL) is used to extend it.
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| @@ -15,6 +15,9 @@ libavutil: 2012-10-22 · 14 unmodified lines | ||
| 15 | 15 | |
| 16 | 16 | API changes, most recent first: |
| 17 | 17 | |
| 18 | +2013-08-xx - xxxxxxx - lavc 55.27.100 - vdpau.h | |
| 19 | + Add a render2 alternative to the render callback function. | |
| 20 | + | |
| 18 | 21 | 2013-08-xx - xxxxxxx - lavc 55.26.100 - vdpau.h |
| 19 | 22 | Add allocation function for AVVDPAUContext, allowing |
| 20 | 23 | to extend it in the future without breaking ABI/API. |