Functions

Function Description

VPC (Vision Preprocessing Core): processes YUV and RGB images. It provides the following key functions:

Cropping: Crops one or more selected regions of interest (ROIs) from an input image.
Resizing: 8K resizing and non-8K resizing are supported for images with different resolution. Single-image cropping and resizing (uncompressed format) and single-image multi-ROI cropping and resizing (uncompressed format) are supported. Supports resizing modes such as original image resizing and proportional resizing (the aspect ratio of the image before and after resizing is the same).
Pasting: crops an image out of an input image, resizes the cropped image, and places it in a specified area of the output image. The output image may be a blank image (when the output buffer allocated by the user is empty) or an existing image (when an image has been read into the output buffer allocated by the user). Note that the pasting concept here refers only to the case when the output image is an existing image.
Stitching: Crops multiple images out of an input image, resizes the cropped images, and places them in a specified area of the output image.
Image pyramid: Performs Gaussian filtering on the original image for multiple times and then downsamples the image to generate images of different sizes.
Histogram analysis: collects statistics on the pixel value distribution of each image channel (RGB/YUV).
Color Remapping: Maps an image to another image based on the configuration information.
Border making: Perform border making on images.
Format conversion: converts between RGB and YUV.
Image grayscale: converts a color image into a grayscale image. The operation of implementing image grayscale is to output an image in YUV400 format. Note that a grayscale input image produces only a grayscale output image.
For Atlas training product , only the data of the Y component is extracted from the YUV420SP output image.

Function Support

The following table lists the functions supported by each version.

Function	Atlas training product	Atlas inference product	Atlas 200I/500 A2 inference product	Atlas A2 training product / Atlas A2 inference product	Atlas A3 training product / Atlas A3 inference product
Cropping	√	√	√	√	√
Resizing:	√	√	√	√	√
Pasting	√	√	√	√	√
Stitching	√	√	√	√	√
Image pyramid	x	√	x	x	x
Histogram analysis	x	√	√	√	√
Remapping	x	√	√	√	√
Border making	x	√	√	√	√
Format conversion	√	√	√	√	√
Image grayscale	√	√	√	√	√

VPC Function Diagram

Only the function diagram is provided here. The alignment restrictions vary depending on the product model. For details, see the usage description of each functional interface.

Figure 1 VPC function diagram (cropping + resizing + pasting)

Figure 2 VPC function diagram (stitching)

Figure 3 Resizing with the aspect ratio preserved (paste ROI centered on the output image)

Due to different alignment constraints, Atlas training product and Atlas inference product also support the following proportional scaling functions:

Figure 4 Resizing with the aspect ratio preserved (paste ROI vertically centered on the output image)

Figure 5 Resizing with the aspect ratio preserved (paste ROI horizontally centered on the output image)

Functions

Function Description

Function Support

VPC Function Diagram

See Also