VkVideoEncodeAV1GopRemainingFrameInfoKHR

The VkVideoEncodeAV1GopRemainingFrameInfoKHR structure is defined as:

typedef struct VkVideoEncodeAV1GopRemainingFrameInfoKHR {
    VkStructureType sType;
    const void* pNext;
    VkBool32 useGopRemainingFrames;
    uint32_t gopRemainingIntra;
    uint32_t gopRemainingPredictive;
    uint32_t gopRemainingBipredictive;
} VkVideoEncodeAV1GopRemainingFrameInfoKHR;

• sType is a VkStructureType value identifying this structure.
• pNext is NULL or a pointer to a structure extending this structure.
• useGopRemainingFrames indicates whether the implementation’s rate control algorithm should use the values specified in gopRemainingIntra, gopRemainingPredictive, and gopRemainingBipredictive. If useGopRemainingFrames is VK_FALSE, then the values of gopRemainingIntra, gopRemainingPredictive, and gopRemainingBipredictive are ignored.
• gopRemainingIntra specifies the number of frames encoded with VK_VIDEO_ENCODE_AV1_RATE_CONTROL_GROUP_INTRA_KHR the implementation’s rate control algorithm should assume to be remaining in the GOP prior to executing the next video encode operation.
• gopRemainingPredictive specifies the number of frames encoded with VK_VIDEO_ENCODE_AV1_RATE_CONTROL_GROUP_PREDICTIVE_KHR the implementation’s rate control algorithm should assume to be remaining in the GOP prior to executing the next video encode operation.
• gopRemainingBipredictive specifies the number of frames encoded with VK_VIDEO_ENCODE_AV1_RATE_CONTROL_GROUP_BIPREDICTIVE_KHR the implementation’s rate control algorithm should assume to be remaining in the GOP prior to executing the next video encode operation.

Setting useGopRemainingFrames to VK_TRUE and including this structure in the pNext chain of VkVideoBeginCodingInfoKHR is only mandatory if the VkVideoEncodeAV1CapabilitiesKHR::requiresGopRemainingFrames reported for the used video profile is VK_TRUE. However, implementations may use these remaining frame counts, when specified, even when it is not required. In particular, when the application does not use a regular GOP structure, these values may provide additional guidance for the implementation’s rate control algorithm.

The VkVideoEncodeAV1CapabilitiesKHR::prefersGopRemainingFrames capability is also used to indicate that the implementation’s rate control algorithm may operate more accurately if the application specifies the remaining frame counts using this structure.

As with other rate control guidance values, if the effective order and number of frames encoded by the application are not in line with the remaining frame counts specified in this structure at any given point, then the behavior of the implementation’s rate control algorithm may deviate from the one expected by the application.