C Specification

The rate control modes are defined with the following enums:

// Provided by VK_KHR_video_encode_queue
typedef enum VkVideoEncodeRateControlModeFlagBitsKHR {
    VK_VIDEO_ENCODE_RATE_CONTROL_MODE_DEFAULT_KHR = 0,
    VK_VIDEO_ENCODE_RATE_CONTROL_MODE_DISABLED_BIT_KHR = 0x00000001,
    VK_VIDEO_ENCODE_RATE_CONTROL_MODE_CBR_BIT_KHR = 0x00000002,
    VK_VIDEO_ENCODE_RATE_CONTROL_MODE_VBR_BIT_KHR = 0x00000004,
} VkVideoEncodeRateControlModeFlagBitsKHR;

Description

  • VK_VIDEO_ENCODE_RATE_CONTROL_MODE_DEFAULT_KHR specifies the use of implementation-specific rate control.

  • VK_VIDEO_ENCODE_RATE_CONTROL_MODE_DISABLED_BIT_KHR specifies that rate control is disabled and any quality control parameters for the encoding are provided on a per-picture basis. In this mode implementations will encode pictures independently of the output bitrate of prior video encode operations. When using an H.264 encode profile, implementations will use the QP values specified in the VkVideoEncodeH264RateControlInfoEXT structure for the encoded picture. When using an H.265 encode profile, implementations will use the QP values specified in the VkVideoEncodeH265RateControlInfoEXT structure for the encoded picture.

  • VK_VIDEO_ENCODE_RATE_CONTROL_MODE_CBR_BIT_KHR specifies the use of constant bitrate rate control mode.

  • VK_VIDEO_ENCODE_RATE_CONTROL_MODE_VBR_BIT_KHR specifies the use of variable bitrate rate control mode.

See Also

VK_KHR_video_encode_queue, VkVideoEncodeQualityLevelPropertiesKHR, VkVideoEncodeRateControlInfoKHR, VkVideoEncodeRateControlModeFlagsKHR

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.

Copyright

Copyright 2014-2023 The Khronos Group Inc.

SPDX-License-Identifier: CC-BY-4.0