Function vaCreateMFContext 

pub unsafe extern "C" fn vaCreateMFContext(
    dpy: VADisplay,
    mf_context: *mut VAMFContextID,
) -> VAStatus

vaCreateMFContext - Create a multi-frame context interface encapsulating common for all streams memory objects and structures required for single GPU task submission from several VAContextID’s. Allocation: This call only creates an instance, doesn’t allocate any additional memory. Support identification: Application can identify multi-frame feature support by ability to create multi-frame context. If driver supports multi-frame - call successful, mf_context != NULL and VAStatus = VA_STATUS_SUCCESS, otherwise if multi-frame processing not supported driver returns VA_STATUS_ERROR_UNIMPLEMENTED and mf_context = NULL. return values: VA_STATUS_SUCCESS - operation successful. VA_STATUS_ERROR_UNIMPLEMENTED - no support for multi-frame. dpy: display adapter. mf_context: Multi-Frame context encapsulating all associated context for multi-frame submission.