sys_set_chn_csc_matrix

Applicability

Product	Supported (√/x)
Atlas A3 training products/Atlas A3 inference products	√
Atlas A2 training products/Atlas A2 inference products	√
Atlas training products	x
Atlas inference products	√
Atlas 200I/500 A2 inference products	√

Function Usage

Sets the CSC parameters after the corresponding image or video processing channel is created if the CSC parameters need to be adjusted in the conversion between YUV and RGB before images or videos are processed.

Prototype

C Prototype

hi_s32 hi_mpi_sys_set_chn_csc_matrix(hi_mod_id mode, hi_s32 chn, hi_csc_matrix csc_matrix, hi_csc_coefficient *csc_coefficient);

Python Function

ret = acl.himpi.sys_set_chn_csc_matrix(mode, chn, csc_matrix, csc_coefficient)

Parameter Description

Parameter	Description
mode	Int, module ID, either HI_ID_VDEC or HI_ID_VPC.
chn	Int, channel ID. When mode is set to HI_ID_VDEC, check the value range of the chn parameter in vdec_create_chn for the channel ID range. When mode is set to HI_ID_VPC, check the value range of the chn parameter in vpc_create_chn for the channel ID range.
csc_matrix	Int, data standard of the CSC matrix. For details, see hi_csc_matrix.
csc_coefficient	Dict, CSC matrix parameter value dictionary. For details, see hi_csc_coefficient. Use csc_coefficient to set the CSC matrix parameters when csc_matrix is set to HI_CSC_MATRIX_USER. Otherwise, pass a random value to this parameter.

Return Value Description

Return Value	Description
ret	Int, error code: 0 on success; else, failure.

Restrictions

If this API is not called to set CSC parameters, the CSC matrix parameters following the BT.601 Wide standard are used by default.
If the default CSC parameters are not applicable, they need to be modified only once for all other tasks in the channel. You can call this API to set CSC parameters after the corresponding image or video processing channel is created. After that, call the specific image or video processing API, and then call the API that obtains the image or video processing result.
If the default CSC parameters are not applicable and different CSC parameters are used for different tasks, modify the parameters for multiple times after the corresponding image or video processing channel is created, after the previous task is complete, and before the next task is executed. (If this API is called again before the previous task is complete, the task processing result may be incorrect.) After that, call the specific image or video processing API, and then call the API that obtains the image or video processing result.
The call sequence is as follows:
1. acl.himpi.sys_set_chn_csc_matrix (first CSC parameter modification)
2. acl.himpi.vpc_crop (cropping)
3. acl.himpi.vpc_get_process_result (waiting for the cropping task to complete)
4. acl.himpi.sys_set_chn_csc_matrix (second CSC parameter modification)
5. acl.himpi.vpc_resize (resizing)
6. acl.himpi.vpc_get_process_result (waiting for the resizing task to complete)

Parent topic: Common APIs