hi_mpi_pngd_create_chn

Applicability

Product	Supported
Atlas 350 Accelerator Card	√
Atlas A3 training product / Atlas A3 inference product	√
Atlas A2 training product / Atlas A2 inference product	√
Atlas 200I/500 A2 inference product	√
Atlas inference product	√
Atlas training product	☓

Function Description

Creates a decoding channel based on the configured channel attributes.

Prototype

hi_s32 hi_mpi_pngd_create_chn(hi_pngd_chn chn, const hi_pngd_chn_attr *attr)

Parameters

Parameter	Input/Output	Description
chn	Input	Decoding channel ID. The value range of this parameter is [0, 128). The maximum number of channels is 128.
attr	Input	Pointer to the decoding channel attributes.

Parameter

Input/Output

Description

chn

Input

Decoding channel ID.

The value range of this parameter is [0, 128). The maximum number of channels is 128.

attr

Input

Pointer to the decoding channel attributes.

Returns

0: success
Other values: failure. For details, see PNGD Return Codes.

Restrictions

The channel ID of a single device must not be greater than the maximum channel ID.
If the attr parameter is empty, the error code HI_ERR_PNGD_NULL_PTR is returned.
Before this API call, ensure that a channel has not been created yet or has been destroyed. Otherwise, a failure is returned.
If the OS memory is insufficient, the error code HI_ERR_PNGD_NO_MEM is returned. In this case, you can expand the OS memory.
When a setting in the channel attributes pointed by attr exceeds the decoding capability set, the error code HI_ERR_PNGD_ILLEGAL_PARAM is returned.
In the Ascend virtual instance scenario, the number of channels must meet the following requirements:
In the Atlas inference product and Ascend virtual instance scenarios, the restrictions on the number of channels vary depending on the Ascend virtual instance template.
- When the vir04_4c_dvpp template is used, the total number of channels is fixed at 128.
- When the vir04_3c_ndvpp template is used, the DVPP function is not used. Therefore, the total number of channels is 0.
- When other templates are used, total number of channels = allocation specification x 128. If the total number of channels is not an integer, round down the value.
In the Atlas A2 training product / Atlas A2 inference product and Ascend virtual instance scenarios, the restrictions on the number of channels vary depending on the Ascend virtual instance template.
- When the vir12_4c_32g_m, vir10_4c_16g_m, or vir10_4c_32g_m template is used, the total number of channels is fixed to 128.
- When the vir12_3c_32g_nm, vir10_3c_16g_nm or vir10_3c_32g_nm template is used, the DVPP function is not used. Therefore, the total number of channels is 0.
You can run the npu-smi info -t template-info command on the server where AI processor is installed to view the computing power specifications of Ascend virtual instance in each scenario.