22 lines
1.2 KiB
Markdown
22 lines
1.2 KiB
Markdown
|
## Frame Info exported from libHEVC
|
|||
|
|
|
|||
|
|
### Introduction
|
|||
|
|
QP and CU type maps for H265 are defined for each 8x8 coding unit.
|
|||
|
|
The QP values defined as unsigned 8-bit numbers can range from <1, 51> and CU type can be
|
|||
|
|
INTER/INTRA/SKIP. HEVC defines them in ihevc_defs.h as PRED_MODE_INTER = 0, PRED_MODE_INTRA = 1
|
|||
|
|
and PRED_MODE_SKIP = 2.
|
|||
|
|
Set the “u4_frame_info_enable” flag to enable encoder/decoder to populate and return the qp values
|
|||
|
|
and CU type data in its output structure ihevcd_cxa_video_decode_op_t via pu1_8x8_blk_qp_map and
|
|||
|
|
pu1_8x8_blk_type_map.
|
|||
|
|
|
|||
|
|
### Mapping to the frame
|
|||
|
|
Within a video sequence, CTUs of a fixed size (16x16, 32x32, or 64x64) can be further divided into
|
|||
|
|
CUs of size as low as 8x8 pixels. A CU’s number of QP entries (each for 8x8 blocks) can range from
|
|||
|
|
1 to 64. A frame with a resolution of WdxHt has a total of (align8(Wd) x align8(Ht)) / 64 entries
|
|||
|
|
for QP and CU type map each. Qp and CU type values for each 8x8 block are stored in raster scan
|
|||
|
|
order. Refer to ihevcd_cxa.h for details.
|
|||
|
|
|
|||
|
|
### Plugin/Application
|
|||
|
|
The encoder/decoder keeps the QP and CU type map as a part of its output handle. The plugins can
|
|||
|
|
access these data through the output structure.
|