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Add VK_EXT_ycbcr_3plane_16bit_lsb_formats extension
This extension adds support for 10/12bit YCbCr formats used by software decoders like ffmpeg, dav1d and libvpx. See https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/34303
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‎appendices/VK_EXT_ycbcr_3plane_16bit_lsb_formats.adoc‎

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// Copyright 2026 The Khronos Group Inc.
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//
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// SPDX-License-Identifier: CC-BY-4.0
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include::{generated}/meta/{refprefix}VK_EXT_ycbcr_3plane_16bit_lsb_formats.adoc[]
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=== Other Extension Metadata
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*Last Modified Date*::
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2026-04-30
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*IP Status*::
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No known IP claims.
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*Contributors*::
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- Robert Mader, Collabora
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=== Description
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This extension adds some 10/12/14bit {YCbCr} formats that are in common use for
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video software encode and decode, but were not part of the
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`apiext:VK_KHR_sampler_ycbcr_conversion` extension.
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include::{generated}/interfaces/VK_EXT_ycbcr_3plane_16bit_lsb_formats.adoc[]
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=== Version History
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* Revision 1, 2026-04-30 (Robert Mader)
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** Initial draft

‎chapters/descriptorbuffers.adoc‎

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@@ -596,6 +596,19 @@ ifdef::VK_BASE_VERSION_1_3[Vulkan 1.3 is not supported and]
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ename:VK_FORMAT_G12X4_B12X4R12X4_2PLANE_444_UNORM_3PACK16, or
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ename:VK_FORMAT_G16_B16R16_2PLANE_444_UNORM
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endif::VK_EXT_ycbcr_2plane_444_formats[]
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ifdef::VK_EXT_ycbcr_3plane_16bit_lsb_formats[]
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* If the <<features-ycbcr3plane16BitLsbFormats,pname:ycbcr3plane16BitLsbFormats>>
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feature is not enabled, pname:format must: not be
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_422_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_444_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_422_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_444_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_422_UNORM_3PACK16_EXT or
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_444_UNORM_3PACK16_EXT
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endif::VK_EXT_ycbcr_3plane_16bit_lsb_formats[]
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****
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include::{generated}/validity/structs/VkDescriptorAddressInfoEXT.adoc[]

‎chapters/features.adoc‎

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@@ -6033,6 +6033,39 @@ endif::VK_BASE_VERSION_1_3[]
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--
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endif::VK_EXT_ycbcr_2plane_444_formats[]
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ifdef::VK_EXT_ycbcr_3plane_16bit_lsb_formats[]
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[open,refpage='VkPhysicalDeviceYcbcr3Plane16BitLsbFormatsFeaturesEXT',desc='Structure describing whether the implementation supports additional 3-plane 16bit LSB {YCbCr} formats',type='structs']
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--
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The sname:VkPhysicalDeviceYcbcr3Plane16BitLsbFormatsFeaturesEXT structure is
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defined as:
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include::{generated}/api/structs/VkPhysicalDeviceYcbcr3Plane16BitLsbFormatsFeaturesEXT.adoc[]
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This structure describes the following feature:
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* pname:sType is a elink:VkStructureType value identifying this structure.
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* pname:pNext is `NULL` or a pointer to a structure extending this
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structure.
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* [[features-ycbcr3plane16BitLsbFormats]] pname:ycbcr3plane16BitLsbFormats
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indicates that the implementation supports querying format features for, and
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using, the following 3-plane 16bit LSB {YCbCr} formats:
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** ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_420_UNORM_3PACK16_EXT
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** ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_422_UNORM_3PACK16_EXT
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** ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_444_UNORM_3PACK16_EXT
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** ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_420_UNORM_3PACK16_EXT
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** ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_422_UNORM_3PACK16_EXT
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** ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_444_UNORM_3PACK16_EXT
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** ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_420_UNORM_3PACK16_EXT
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** ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_422_UNORM_3PACK16_EXT
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** ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_444_UNORM_3PACK16_EXT
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:refpage: VkPhysicalDeviceYcbcr3Plane16BitLsbFormatsFeaturesEXT
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include::{chapters}/features.adoc[tag=features]
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include::{generated}/validity/structs/VkPhysicalDeviceYcbcr3Plane16BitLsbFormatsFeaturesEXT.adoc[]
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--
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endif::VK_EXT_ycbcr_3plane_16bit_lsb_formats[]
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ifdef::VK_EXT_color_write_enable[]
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[open,refpage='VkPhysicalDeviceColorWriteEnableFeaturesEXT',desc='Structure describing whether writes to color attachments can be enabled and disabled dynamically',type='structs']
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--

‎chapters/formats.adoc‎

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@@ -2081,6 +2081,19 @@ ifdef::VK_KHR_maintenance5,VK_BASE_VERSION_1_3[and]
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ename:VK_FORMAT_G16_B16R16_2PLANE_444_UNORM
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****
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endif::VK_EXT_ycbcr_2plane_444_formats[]
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ifdef::VK_EXT_ycbcr_3plane_16bit_lsb_formats[]
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* If the <<features-ycbcr3plane16BitLsbFormats,pname:ycbcr3plane16BitLsbFormats>>
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feature is not enabled, pname:format must: not be
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_422_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_444_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_422_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_444_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_422_UNORM_3PACK16_EXT or
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_444_UNORM_3PACK16_EXT
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endif::VK_EXT_ycbcr_3plane_16bit_lsb_formats[]
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include::{generated}/validity/protos/vkGetPhysicalDeviceFormatProperties.adoc[]
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--
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flink:vkGetPhysicalDeviceFormatProperties, with the ability to return
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extended information in a pname:pNext chain of output structures.
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ifdef::VK_EXT_ycbcr_2plane_444_formats[]
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.Valid Usage
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****
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ifdef::VK_EXT_ycbcr_2plane_444_formats[]
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* [[VUID-vkGetPhysicalDeviceFormatProperties2-None-12273]]
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If
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ifdef::VK_BASE_VERSION_1_3[Vulkan 1.3 is not supported,]
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ename:VK_FORMAT_G10X6_B10X6R10X6_2PLANE_444_UNORM_3PACK16,
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ename:VK_FORMAT_G12X4_B12X4R12X4_2PLANE_444_UNORM_3PACK16, or
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ename:VK_FORMAT_G16_B16R16_2PLANE_444_UNORM
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****
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endif::VK_EXT_ycbcr_2plane_444_formats[]
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ifdef::VK_EXT_ycbcr_3plane_16bit_lsb_formats[]
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* If the <<features-ycbcr3plane16BitLsbFormats,pname:ycbcr3plane16BitLsbFormats>>
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feature is not enabled, pname:format must: not be
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_422_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_444_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_422_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_444_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_422_UNORM_3PACK16_EXT or
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_444_UNORM_3PACK16_EXT
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endif::VK_EXT_ycbcr_3plane_16bit_lsb_formats[]
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****
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include::{generated}/validity/protos/vkGetPhysicalDeviceFormatProperties2.adoc[]
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--

‎chapters/resources.adoc‎

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ename:VK_FORMAT_G12X4_B12X4R12X4_2PLANE_444_UNORM_3PACK16, or
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ename:VK_FORMAT_G16_B16R16_2PLANE_444_UNORM
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endif::VK_EXT_ycbcr_2plane_444_formats[]
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ifdef::VK_EXT_ycbcr_3plane_16bit_lsb_formats[]
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* If the <<features-ycbcr3plane16BitLsbFormats,pname:ycbcr3plane16BitLsbFormats>>
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feature is not enabled, pname:format must: not be
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_422_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_444_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_422_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_444_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_422_UNORM_3PACK16_EXT or
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_444_UNORM_3PACK16_EXT
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endif::VK_EXT_ycbcr_3plane_16bit_lsb_formats[]
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****
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include::{generated}/validity/structs/VkBufferViewCreateInfo.adoc[]
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ename:VK_FORMAT_G12X4_B12X4R12X4_2PLANE_444_UNORM_3PACK16, or
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ename:VK_FORMAT_G16_B16R16_2PLANE_444_UNORM
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endif::VK_EXT_ycbcr_2plane_444_formats[]
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ifdef::VK_EXT_ycbcr_3plane_16bit_lsb_formats[]
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* If the <<features-ycbcr3plane16BitLsbFormats,pname:ycbcr3plane16BitLsbFormats>>
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feature is not enabled, pname:format must: not be
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_422_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_444_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_422_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_444_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_422_UNORM_3PACK16_EXT or
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_444_UNORM_3PACK16_EXT
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endif::VK_EXT_ycbcr_3plane_16bit_lsb_formats[]
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ifdef::VK_EXT_descriptor_heap[]
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* [[VUID-VkImageCreateInfo-flags-11281]]
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If slink:VkOpaqueCaptureDataCreateInfoEXT::pname:pData is not `NULL`,
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ename:VK_FORMAT_G12X4_B12X4R12X4_2PLANE_444_UNORM_3PACK16, or
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ename:VK_FORMAT_G16_B16R16_2PLANE_444_UNORM
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endif::VK_EXT_ycbcr_2plane_444_formats[]
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ifdef::VK_EXT_ycbcr_3plane_16bit_lsb_formats[]
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* If the <<features-ycbcr3plane16BitLsbFormats,pname:ycbcr3plane16BitLsbFormats>>
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feature is not enabled, pname:format must: not be
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_422_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X6G10_X6B10_X6R10_3PLANE_444_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_422_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X4G12_X4B12_X4R12_3PLANE_444_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_420_UNORM_3PACK16_EXT,
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_422_UNORM_3PACK16_EXT or
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ename:VK_FORMAT_X2G14_X2B14_X2R14_3PLANE_444_UNORM_3PACK16_EXT
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endif::VK_EXT_ycbcr_3plane_16bit_lsb_formats[]
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****
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include::{generated}/validity/structs/VkImageViewCreateInfo.adoc[]

‎proposals/VK_EXT_ycbcr_3plane_16bit_lsb_formats.adoc‎

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// Copyright 2026 The Khronos Group Inc.
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//
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// SPDX-License-Identifier: CC-BY-4.0
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= VK_EXT_ycbcr_3plane_16bit_lsb_formats
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:toc: left
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:docs: https://docs.vulkan.org/spec/latest/
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:extensions: {docs}appendices/extensions.html#
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:sectnums:
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This extension adds support for 10/12/14 bit {YCbCr} formats used by software
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decoders like ffmpeg, dav1d and libvpx.
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== Problem Statement
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Many popular software video decoders - such as ffmpeg/libav, dav1d and libvpx -
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use formats for 10, 12 and 14 bit content that are not yet supported in Vulkan,
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but are supported by Linux DRM and Mesa GLES (at least the 10 and 12 bit ones).
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These formats are long established and optimized for the given task and it would
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be very hard for decoders to switch to formats optimized for hardware video
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decoders such as P010.
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Supporting these formats directly in drivers has various advantages for apps
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and system compositors, as it allows to avoid unnecessary copies and/or quality
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loss. Further more it can also simplify code-sharing with code-paths for
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hardware decoders.
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Unfortunately it is not possible to use the existing 16 bit formats such as
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VK_FORMAT_G16_B16_R16_3PLANE_420_UNORM as - unlike most formats used by hardware
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decoders - the alignment is LSB, not MSB. The bit-values thus need to get
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shifted by 6, 4 or 2 bits.
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== Proposal
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Add the formats in question. For any drivers already supporting YCbCr formats
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via shaders this should be straight forward. Values in the 0.0 - 1.0 range just
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need to get multiplied by 65535.0 / 1023.0 (for 10 bit), 65535.0 / 4095.0 (for
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12 bit) or 65535.0 / 16383.0 (for 14 bit).
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== Issues

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