hi_mpi_vpc_calc_hist

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

Calculates a histogram of image channels. This API is asynchronous.

Prototype

hi_s32 hi_mpi_vpc_calc_hist(hi_vpc_chn chn, const hi_vpc_pic_info *source_pic, hi_vpc_histogram_config *hist_config, hi_u32 *task_id, hi_s32 milli_sec)

Parameters

Parameter	Input/Output	Description
chn	Input	Channel ID for image processing. Atlas 350 Accelerator Card: The value range is [0, 256). The maximum number of channels is 256. Atlas A3 training product/Atlas A3 inference product: The value range is [0, 256). The maximum number of channels is 256. Atlas A2 training product/Atlas A2 inference product: The value range is [0, 256). The maximum number of channels is 256. Atlas 200I/500 A2 inference product: The value range is [0, 128). The maximum number of channels is 128. Atlas inference product: The value range is [0, 256). The maximum number of channels is 256.
source_pic	Input	Pointer to the input image information. When the image format is YUV440SP 8-bit or YVU440SP 8-bit, the Y component statistics are accurate, but the UV component statistics are inaccurate.
hist_config	Output	Pointer to the statistics result. hist_config is a struct that contains three arrays, which store the distribution (0–255) of the three components of each image.
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

hist_config: result histogram.
task_id: task ID, used to identify a task.

Restrictions

Requirements on the input resolution:

Model	Input image resolution range
Atlas inference product	[106, 40964096]
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	[106, 40968192]

Model

Input image resolution range

Atlas inference product

[10*6, 4096*4096]

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

[10*6, 4096*8192]

The input image format supports the following enumerated values of hi_pixel_format:

HI_PIXEL_FORMAT_YUV_400 = 0,              // YUV400 8bit
HI_PIXEL_FORMAT_YUV_SEMIPLANAR_420 = 1,    // YUV420SP NV12 8bit   
HI_PIXEL_FORMAT_YVU_SEMIPLANAR_420 = 2,    // YUV420SP NV21 8bit 
HI_PIXEL_FORMAT_YUV_SEMIPLANAR_422 = 3,    // YUV422SP 8bit
HI_PIXEL_FORMAT_YVU_SEMIPLANAR_422 = 4,    // YVU422SP 8bit
HI_PIXEL_FORMAT_YUV_SEMIPLANAR_444 = 5,    // YUV444SP 8bit
HI_PIXEL_FORMAT_YVU_SEMIPLANAR_444 = 6,    // YVU444SP 8bit
HI_PIXEL_FORMAT_YUYV_PACKED_422 = 7,       // YUV422Packed YUYV 8bit
HI_PIXEL_FORMAT_UYVY_PACKED_422 = 8,       // YUV422Packed UYVY 8bit
HI_PIXEL_FORMAT_YVYU_PACKED_422 = 9,       // YUV422Packed YVYU 8bit
HI_PIXEL_FORMAT_VYUY_PACKED_422 = 10,      // YUV422Packed VYUY 8bit
HI_PIXEL_FORMAT_YUV_PACKED_444 = 11,       // YUV444P 8bit
HI_PIXEL_FORMAT_RGB_888 = 12,              // RGB888
HI_PIXEL_FORMAT_BGR_888 = 13,              // BGR888
HI_PIXEL_FORMAT_YUV_SEMIPLANAR_440 = 1000, // YUV440SP 8bit 
HI_PIXEL_FORMAT_YVU_SEMIPLANAR_440 = 1001, // YVU440SP 8bit

For details about the restrictions on the width and height alignment and buffer size of each image format, see Restrictions on Image Formats, Width and Height Alignment, and Buffers.

Parent topic: VPC