DSP

FastCV主要接口分析之五

2019-07-13 18:57发布

FastCV主要接口分析之五     15.像素描述函数         FASTCV_API int fcvDescriptorSampledMeanAndVar36f32( const float* __restrict src,
                                     int                     first,
                                     int                     last,
                                     int32_t*                vind,
                                     float* __restrict       means,
                                     float* __restrict       vars,
                                     float* __restrict       temp );
        此函数的作用是计算NFT4浮点的范围的近似均值和方差,沿维度描述元素的描述符被视为随机vars。
    16.获取最大NCC值         FASTCV_API int fcvNCCPatchOnCircle8x8u8( const uint8_t* __restrict patch,
                          const uint8_t* __restrict src,
                          unsigned short            srcWidth,
                          unsigned short            srcHeight,
                          unsigned short            search_center_x,
                          unsigned short            search_center_y,
                          unsigned short            search_radius,
                          uint16_t*                 best_x,
                          uint16_t*                 best_y,
                          uint32_t*                 bestNCC,
                          int                       findSubPixel,
                          float*                    subX,
                          float*                    subY );
        此函数的主要作用是,获取一个像素点周围8X8半径区域内的最大NCC值。
        FASTCV_API int fcvNCCPatchOnSquare8x8u8( const uint8_t* __restrict patch,
                          const uint8_t* __restrict src,
                          unsigned short            srcWidth,
                          unsigned short            srcHeight,
                          unsigned short            search_center_x,
                          unsigned short            search_center_y,
                          unsigned short            search_w,
                          uint16_t*                 best_x,
                          uint16_t*                 best_y,
                          uint32_t*                 bestNCC,
                          int                       doSubPixel,
                          float*                    subX,
                          float*                    subY );
        此函数的主要作用是,获取一个像素点周围8X8正方形区域内的最大NCC值。
    17.图像对比         FASTCV_API void fcvSumOfAbsoluteDiffsxxx( const uint8_t* __restrict patch,
                            const uint8_t* __restrict src,
                            unsigned int              srcWidth,
                            unsigned int              srcHeight,
                            unsigned int              srcStride,
                            uint16_t* __restrict      dst );
        此是一些列函数,主要功能是计算一个图像和8X8样版图像对比的绝对差值之和。
    18.修改图像灰度         FASTCV_API int fcvScaleDownByxxx( const uint8_t* __restrict src,
                   unsigned int              srcWidth,
                   unsigned int              srcHeight,
                   uint8_t* __restrict       dst );
        此是一些列函数,主要功能是通过使用某种算法(高斯过滤器),降低图像的尺寸,平均NXN像素到一个像素点,使其长和宽降为原来的1/x。
        FASTCV_API void fcvScaleUpByxxx( const uint8_t* __restrict src,
                            unsigned int              srcWidth,
                            unsigned int              srcHeight,
                            uint8_t* __restrict       dst );
        此是一些列函数,主要功能是通过某种算法(高斯过滤器),提高灰阶图像。
    19.提高灰阶图像         FASTCV_API void fcvFilterDilatexxx( const uint8_t* __restrict src,
                      unsigned int              srcWidth,
                      unsigned int              srcHeight,
                      uint8_t* __restrict       dst );
        此是一系列函数,主要功能是通过nxn相邻窗口局部最大值提升一个灰度图像。