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hi_mpi_vpc_pyrdown

The Atlas 200/300/500 Inference Product does not support this API.

The Atlas Training Series Product does not support this API.

Description

Downsamples an image using a pyramid. Only YUV400 format images are supported. This API is asynchronous.

Prototype

hi_s32 hi_mpi_vpc_pyrdown(hi_vpc_chn chn, const hi_vpc_pic_info *source_pic, hi_vpc_pic_info dest_pic[], hi_u32 filter_level, hi_s8 gaussian_filter[][5], hi_u16 divisor, hi_vpc_make_border_info make_border_info, hi_u32 *task_id, hi_s32 milli_sec)

Parameters

Parameter

Input/Output

Description

chn

Input

Channel ID for image processing.

source_pic

Input

Pointer to the input image information. Only YUV400 format images are supported. The allowed maximum resolution is 2048 x 2048. The allowed minimum resolution varies with filter_level as follows:

If filter_level = 1, the allowed minimum resolution is 20 x 12.

If filter_level = 2, the allowed minimum resolution is 40 x 24.

If filter_level = 3, the allowed minimum resolution is 80 x 48.

If filter_level = 4, the allowed minimum resolution is 160 x 96.

dest_pic

Input

Destination image information. The array length is the same as that of the filter_level value.

dest_pic[0] saves the source image to 1/2 the original size. dest_pic[1] saves the source image to 1/4 the original size. dest_pic[2] saves the source image to 1/8 the original size. dest_pic[3] saves the source image to 1/16 the original size.

filter_level

Input

Number of layers in the pyramid. Must be in the range of [1, 4].

gaussian_filter

Input

Gaussian filtering parameter.

If this parameter is set to a null pointer, the following default values are used:

{{1, 4, 6, 4, 1},

{4, 16, 24, 16, 4},

{6, 24, 36, 24, 6},

{4, 16, 24, 16, 4},

{1, 4, 6, 4, 1}}

divisor

Input

Divisor of the filter. Must be a power of 2.

make_border_info

Input

Border making information.

A border with a length of 2 pixels is created. The supported border types are HI_BORDER_CONSTANT, HI_BOARD_REPLICATE, and HI_BOARD_REFLECT.

task_id

Output

Pointer to the task ID, used to identify a task.

milli_sec

Input
Timeout interval (ms).
  • -1: blocking mode.
  • 0: non-blocking mode.
  • > 0: timeout interval (timeout mode). The timeout interval varies with the operating system. The deviation is generally within a time slice of an operating system. For example, if the time slice of an operating system is 4 ms and the value of milli_sec is set to 1, the actual timeout interval ranges from 1 ms to 5 ms. When the CPU load is high, the timeout interval may fluctuate.

Returns

Parent topic: VPC