Registered Extension Number

300

Revision

8

Extension and Version Dependencies

  • This is a provisional extension and must be used with caution. See the description of provisional header files for enablement and stability details.

Contact

Other Extension Metadata

Last Modified Date

2023-03-06

IP Status

No known IP claims.

Contributors
  • Ahmed Abdelkhalek, AMD

  • Damien Kessler, NVIDIA

  • George Hao, AMD

  • Jake Beju, AMD

  • Peter Fang, AMD

  • Piers Daniell, NVIDIA

  • Srinath Kumarapuram, NVIDIA

  • Thomas J. Meier, NVIDIA

  • Tony Zlatinski, NVIDIA

  • Yang Liu, AMD

  • Daniel Rakos, RasterGrid

Description

This extension builds upon the VK_KHR_video_queue extension by adding common APIs specific to video encoding and thus enabling implementations to expose queue families supporting video encode operations.

More specifically, it adds video encode specific capabilities and a new command buffer command that allows recording video encode operations against a video session.

This extension is to be used in conjunction with other codec specific video encode extensions that enable encoding video sequences of specific video compression standards.

New Commands

New Structures

New Enums

New Bitmasks

New Enum Constants

  • VK_KHR_VIDEO_ENCODE_QUEUE_EXTENSION_NAME

  • VK_KHR_VIDEO_ENCODE_QUEUE_SPEC_VERSION

  • Extending VkAccessFlagBits2:

    • VK_ACCESS_2_VIDEO_ENCODE_READ_BIT_KHR

    • VK_ACCESS_2_VIDEO_ENCODE_WRITE_BIT_KHR

  • Extending VkBufferUsageFlagBits:

    • VK_BUFFER_USAGE_VIDEO_ENCODE_DST_BIT_KHR

    • VK_BUFFER_USAGE_VIDEO_ENCODE_SRC_BIT_KHR

  • Extending VkFormatFeatureFlagBits:

    • VK_FORMAT_FEATURE_VIDEO_ENCODE_DPB_BIT_KHR

    • VK_FORMAT_FEATURE_VIDEO_ENCODE_INPUT_BIT_KHR

  • Extending VkImageLayout:

    • VK_IMAGE_LAYOUT_VIDEO_ENCODE_DPB_KHR

    • VK_IMAGE_LAYOUT_VIDEO_ENCODE_DST_KHR

    • VK_IMAGE_LAYOUT_VIDEO_ENCODE_SRC_KHR

  • Extending VkImageUsageFlagBits:

    • VK_IMAGE_USAGE_VIDEO_ENCODE_DPB_BIT_KHR

    • VK_IMAGE_USAGE_VIDEO_ENCODE_DST_BIT_KHR

    • VK_IMAGE_USAGE_VIDEO_ENCODE_SRC_BIT_KHR

  • Extending VkPipelineStageFlagBits2:

    • VK_PIPELINE_STAGE_2_VIDEO_ENCODE_BIT_KHR

  • Extending VkQueryType:

    • VK_QUERY_TYPE_VIDEO_ENCODE_FEEDBACK_KHR

  • Extending VkQueueFlagBits:

    • VK_QUEUE_VIDEO_ENCODE_BIT_KHR

  • Extending VkResult:

    • VK_ERROR_INVALID_VIDEO_STD_PARAMETERS_KHR

  • Extending VkStructureType:

    • VK_STRUCTURE_TYPE_QUERY_POOL_VIDEO_ENCODE_FEEDBACK_CREATE_INFO_KHR

    • VK_STRUCTURE_TYPE_VIDEO_ENCODE_CAPABILITIES_KHR

    • VK_STRUCTURE_TYPE_VIDEO_ENCODE_INFO_KHR

    • VK_STRUCTURE_TYPE_VIDEO_ENCODE_RATE_CONTROL_INFO_KHR

    • VK_STRUCTURE_TYPE_VIDEO_ENCODE_RATE_CONTROL_LAYER_INFO_KHR

    • VK_STRUCTURE_TYPE_VIDEO_ENCODE_USAGE_INFO_KHR

  • Extending VkVideoCodingControlFlagBitsKHR:

    • VK_VIDEO_CODING_CONTROL_ENCODE_RATE_CONTROL_BIT_KHR

    • VK_VIDEO_CODING_CONTROL_ENCODE_RATE_CONTROL_LAYER_BIT_KHR

If VK_KHR_format_feature_flags2 is supported:

  • Extending VkFormatFeatureFlagBits2:

    • VK_FORMAT_FEATURE_2_VIDEO_ENCODE_DPB_BIT_KHR

    • VK_FORMAT_FEATURE_2_VIDEO_ENCODE_INPUT_BIT_KHR

Issues

1) Why is there no VK_PIPELINE_STAGE_VIDEO_ENCODE_BIT_KHR?

RESOLVED: This extension requires VK_KHR_synchronization2 because the new access flags introduced did not fit in the 32-bit enum VkAccessFlagBits. Accordingly, all new pipeline stage and access flags have been added to the corresponding 64-bit enum and no new flags have been added to the legacy 32-bit enums. While the new pipeline stage flag introduced uses bit #27 which would also fit in the legacy VkPipelineStageFlagBits enum, there is no real benefit to include it. Instead the bit is marked reserved.

Version History

  • Revision 1, 2018-07-23 (Ahmed Abdelkhalek)

    • Initial draft

  • Revision 1.1, 10/29/2019 (Tony Zlatinski)

    • Updated the reserved spec tokens and renamed VkVideoEncoderKHR to VkVideoSessionKHR

  • Revision 1.6, Jan 08 2020 (Tony Zlatinski)

    • API unify with the video_decode_queue spec

  • Revision 2, March 29 2021 (Tony Zlatinski)

    • Spec and API updates.

  • Revision 3, 2021-09-30 (Jon Leech)

  • Revision 4, 2022-02-10 (Ahmed Abdelkhalek)

    • Updates to encode capability interface

  • Revision 5, 2022-03-31 (Ahmed Abdelkhalek)

    • Remove redundant VkVideoEncodeInfoKHR.codedExtent

  • Revision 6, 2022-07-18 (Daniel Rakos)

    • Remove VkVideoEncodeRateControlFlagBitsKHR and VkVideoEncodeFlagBitsKHR as they contain no defined flags for now

    • Add VK_VIDEO_CODING_CONTROL_ENCODE_RATE_CONTROL_BIT_KHR and VK_VIDEO_CODING_CONTROL_ENCODE_RATE_CONTROL_LAYER_BIT_KHR to indicate rate control and rate control layer change requests, respectively, in video coding control operations

  • Revision 7, 2022-08-12 (Daniel Rakos)

    • Add VkVideoEncodeUsageInfoKHR structure and related flags

  • Revision 8, 2023-03-06 (Daniel Rakos)

    • Replace VK_QUERY_TYPE_VIDEO_ENCODE_BITSTREAM_BUFFER_RANGE_KHR queries with more generic VK_QUERY_TYPE_VIDEO_ENCODE_FEEDBACK_KHR queries that can be extended in the future with more feedback values

    • Rename dstBitstreamBuffer, dstBitstreamBufferOffset, and dstBitstreamBufferMaxRange in VkVideoEncodeInfoKHR to dstBuffer, dstBufferOffset, and dstBufferRange, respectively, for consistency with the naming convention in the video decode extensions

    • Change the type of rateControlLayerCount and qualityLevelCount in VkVideoEncodeCapabilitiesKHR from uint8_t to uint32_t and rename them to maxRateControlLayers and maxQualityLevels, respectively

    • Change the type of averageBitrate and maxBitrate in VkVideoEncodeRateControlLayerInfoKHR` from uint32_t to uint64_t

    • Fixed the definition of rate control flag bits and added the new VK_VIDEO_ENCODE_RATE_CONTROL_MODE_DEFAULT_KHR constant to indicate implementation-specific automatic rate control

    • Change the type of VkVideoEncodeRateControlInfoKHR::layerCount from uint8_t to uint32_t

    • Rename pLayerConfigs to pLayers in VkVideoEncodeRateControlInfoKHR

See Also

Document Notes

For more information, see the Vulkan Specification

This page is a generated document. Fixes and changes should be made to the generator scripts, not directly.

Copyright 2014-2023 The Khronos Group Inc.

SPDX-License-Identifier: CC-BY-4.0