VA-API  2.19.0
Public Attributes | List of all members
VAEncROI Struct Reference

Encoding region-of-interest (ROI). More...

#include <va.h>

Public Attributes

VARectangle roi_rectangle
 Defines the ROI boundary in pixels, the driver will map it to appropriate codec coding units. It is relative to frame coordinates for the frame case and to field coordinates for the field case.
 
int8_t roi_value
 ROI value. More...
 

Detailed Description

Encoding region-of-interest (ROI).

The encoding ROI can be set through VAEncMiscParameterBufferROI, if the implementation supports ROI input. The ROI set through this structure is applicable only to the current frame or field, so must be sent every frame or field to be applied. The number of supported ROIs can be queried through the VAConfigAttribEncROI. The encoder will use the ROI information to adjust the QP values of the MB's that fall within the ROIs.

Member Data Documentation

◆ roi_value

int8_t VAEncROI::roi_value

ROI value.

roi_value specifies ROI delta QP or ROI priority. – ROI delta QP is the value that will be added on top of the frame level QP. – ROI priority specifies the priority of a region, it can be positive (more important) or negative (less important) values and is compared with non-ROI region (taken as value 0), E.g. ROI region with roi_value -3 is less important than the non-ROI region (roi_value implied to be 0) which is less important than ROI region with roi_value +2. For overlapping regions, the roi_value that is first in the ROI array will have priority.

roi_value always specifes ROI delta QP when VAConfigAttribRateControl == VA_RC_CQP, no matter the value of roi_value_is_qp_delta in #VAEncMiscParameterBufferROI.

roi_value depends on roi_value_is_qp_delta in #VAEncMiscParameterBufferROI when VAConfigAttribRateControl != VA_RC_CQP. roi_value specifies ROI_delta QP if roi_value_is_qp_delta in VAEncMiscParameterBufferROI is 1, otherwise roi_value specifies ROI priority.


The documentation for this struct was generated from the following file: