C Specification
The VkVideoEncodeH264RateControlInfoKHR structure is defined as:
// Provided by VK_KHR_video_encode_h264
typedef struct VkVideoEncodeH264RateControlInfoKHR {
VkStructureType sType;
const void* pNext;
VkVideoEncodeH264RateControlFlagsKHR flags;
uint32_t gopFrameCount;
uint32_t idrPeriod;
uint32_t consecutiveBFrameCount;
uint32_t temporalLayerCount;
} VkVideoEncodeH264RateControlInfoKHR;
Members
-
sTypeis a VkStructureType value identifying this structure. -
pNextisNULLor a pointer to a structure extending this structure. -
flagsis a bitmask of VkVideoEncodeH264RateControlFlagBitsKHR specifying H.264 rate control flags. -
gopFrameCountis the number of frames within a group of pictures (GOP) intended to be used by the application. If it is set to 0, the rate control algorithm may assume an implementation-dependent GOP length. If it is set toUINT32_MAX, the GOP length is treated as infinite. -
idrPeriodis the interval, in terms of number of frames, between two IDR frames (see IDR period). If it is set to 0, the rate control algorithm may assume an implementation-dependent IDR period. If it is set toUINT32_MAX, the IDR period is treated as infinite. -
consecutiveBFrameCountis the number of consecutive B frames between I and/or P frames within the GOP. -
temporalLayerCountspecifies the number of H.264 temporal layers that the application intends to use.
Description
When an instance of this structure is included in the pNext chain of
the VkVideoCodingControlInfoKHR structure passed to the
vkCmdControlVideoCodingKHR command, and
VkVideoCodingControlInfoKHR::flags includes
VK_VIDEO_CODING_CONTROL_ENCODE_RATE_CONTROL_BIT_KHR, the parameters in
this structure are used as guidance for the implementation’s rate control
algorithm (see Video Coding Control).
If flags includes
VK_VIDEO_ENCODE_H264_RATE_CONTROL_ATTEMPT_HRD_COMPLIANCE_BIT_KHR, then
the rate control state is reset to an initial state to meet HRD compliance
requirements.
Otherwise the new rate control state may be applied without a reset
depending on the implementation and the specified rate control parameters.
|
Note
It would be possible to infer the picture type to be used when encoding a
frame, on the basis of the values provided for |
Document Notes
For more information, see the Vulkan Specification
This page is extracted from the Vulkan Specification. Fixes and changes should be made to the Specification, not directly.