vkCmdControlVideoCodingKHR

To apply dynamic controls to the currently bound video session object, call:

void vkCmdControlVideoCodingKHR(
    VkCommandBuffer commandBuffer,
    const VkVideoCodingControlInfoKHR* pCodingControlInfo);

• commandBuffer is the command buffer in which to record the command.
• pCodingControlInfo is a pointer to a VkVideoCodingControlInfoKHR structure specifying the control parameters.

The control parameters provided in this call are applied to the video session at the time the command executes on the device and are in effect until a subsequent call to this command with the same video session bound changes the corresponding control parameters.

A newly created video session must be reset before performing video coding operations using it by including VK_VIDEO_CODING_CONTROL_RESET_BIT_KHR in pCodingControlInfo→flags. The reset operation also returns all DPB slots of the video session to the inactive state. Correspondingly, any DPB slot index associated with the bound reference picture resources is removed.

For encode sessions, the reset operation returns rate control configuration to implementation default settings and sets the video encode quality level to zero.

After video coding operations are performed using a video session, the reset operation can be used to return the video session to the same initial state as after the reset of a newly created video session. This can be used, for example, when different video sequences are needed to be processed with the same video session object.

If pCodingControlInfo→flags includes VK_VIDEO_CODING_CONTROL_ENCODE_RATE_CONTROL_BIT_KHR, then the command replaces the rate control configuration maintained by the video session with the configuration specified in the VkVideoEncodeRateControlInfoKHR structure included in the pCodingControlInfo→pNext chain.

If pCodingControlInfo→flags includes VK_VIDEO_CODING_CONTROL_ENCODE_QUALITY_LEVEL_BIT_KHR, then the command changes the current video encode quality level to the value specified in the qualityLevel member of the VkVideoEncodeQualityLevelInfoKHR structure included in the pCodingControlInfo→pNext chain.