Allocate a new frame attached to the given AVHWFramesContext.
@param hwframe_ctx a reference to an AVHWFramesContext
@param frame an empty (freshly allocated or unreffed) frame to be filled with
newly allocated buffers.
@param flags currently unused, should be set to zero
@return 0 on success, a negative AVERROR code on failure
Allocate a new frame attached to the given AVHWFramesContext.
@param hwframe_ctx a reference to an AVHWFramesContext @param frame an empty (freshly allocated or unreffed) frame to be filled with newly allocated buffers. @param flags currently unused, should be set to zero @return 0 on success, a negative AVERROR code on failure