VkVideoFormatH265QuantizationMapPropertiesKHR

When calling vkGetPhysicalDeviceVideoFormatPropertiesKHR, the VkVideoFormatH265QuantizationMapPropertiesKHR structure can be included in the pNext chain of the VkVideoFormatPropertiesKHR structure to retrieve video format properties specific to video encode quantization maps used with an H.265 encode profile.

The VkVideoFormatH265QuantizationMapPropertiesKHR structure is defined as:

typedef struct VkVideoFormatH265QuantizationMapPropertiesKHR {
    VkStructureType sType;
    void* pNext;
    VkVideoEncodeH265CtbSizeFlagsKHR compatibleCtbSizes;
} VkVideoFormatH265QuantizationMapPropertiesKHR;

• sType is a VkStructureType value identifying this structure.
• pNext is NULL or a pointer to a structure extending this structure.
• compatibleCtbSizes is a bitmask of VkVideoEncodeH265CtbSizeFlagBitsKHR indicating the CTB sizes that quantization maps using this video format are compatible with.

  The value of compatibleCtbSizes does not limit the use of the specific quantization map format, but does limit the implementation in being able to encode pictures with CTB sizes not included in compatibleCtbSizes but otherwise supported by the used video profile, as indicated by VkVideoEncodeH265CapabilitiesKHR::ctbSizes. In particular, using smaller quantization map texel sizes may prevent implementations from encoding with larger CTB sizes which may have a negative impact on the efficiency of the encoder.

The values returned in this structure are only defined if the allowed image usage flags returned in VkVideoFormatPropertiesKHR::imageUsageFlags for this video format include VK_IMAGE_USAGE_VIDEO_ENCODE_QUANTIZATION_DELTA_MAP_BIT_KHR or VK_IMAGE_USAGE_VIDEO_ENCODE_EMPHASIS_MAP_BIT_KHR.