1/* 2 * Copyright (c) 2016-2021 Arm Limited. 3 * 4 * SPDX-License-Identifier: MIT 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a copy 7 * of this software and associated documentation files (the "Software"), to 8 * deal in the Software without restriction, including without limitation the 9 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or 10 * sell copies of the Software, and to permit persons to whom the Software is 11 * furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in all 14 * copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 22 * SOFTWARE. 23 */ 24#include "helpers.h" 25 26/** This function performs Non maxima suppression over a 3x3 window on a given image. 27 * 28 * @param[in] src_ptr Pointer to the source image. Supported data types: U8/F32 29 * @param[in] src_stride_x Stride of the source image in X dimension (in bytes) 30 * @param[in] src_step_x src_stride_x * number of elements along X processed per workitem(in bytes) 31 * @param[in] src_stride_y Stride of the source image in Y dimension (in bytes) 32 * @param[in] src_step_y src_stride_y * number of elements along Y processed per workitem(in bytes) 33 * @param[in] src_offset_first_element_in_bytes The offset of the first element in the source image 34 * @param[out] dst_ptr Pointer to the destination image. Supported data types: same as @p scr_ptr 35 * @param[in] dst_stride_x Stride of the destination image in X dimension (in bytes) 36 * @param[in] dst_step_x dst_stride_x * number of elements along X processed per workitem(in bytes) 37 * @param[in] dst_stride_y Stride of the destination image in Y dimension (in bytes) 38 * @param[in] dst_step_y dst_stride_y * number of elements along Y processed per workitem(in bytes) 39 * @param[in] dst_offset_first_element_in_bytes The offset of the first element in the destination image 40 */ 41__kernel void non_max_suppression( 42 IMAGE_DECLARATION(src), 43 IMAGE_DECLARATION(dst)) 44{ 45 Image src = CONVERT_TO_IMAGE_STRUCT(src); 46 Image dst = CONVERT_TO_IMAGE_STRUCT(dst); 47 48 VEC_DATA_TYPE(DATA_TYPE, 8) 49 vc = vload8(0, (__global DATA_TYPE *)src.ptr); 50 51 if(all(vc == (DATA_TYPE)0)) 52 { 53 vstore8(0, 0, (__global DATA_TYPE *)dst.ptr); 54 55 return; 56 } 57 58 VEC_DATA_TYPE(DATA_TYPE, 16) 59 nc = vload16(0, (__global DATA_TYPE *)offset(&src, -1, -1)); 60 VEC_DATA_TYPE(DATA_TYPE, 8) 61 out = select((DATA_TYPE)0, vc, (vc >= nc.s01234567) && (vc >= nc.s12345678) && (vc >= nc.s23456789)); 62 63 nc = vload16(0, (__global DATA_TYPE *)offset(&src, -1, 0)); 64 out = select((DATA_TYPE)0, out, (vc >= nc.s01234567) && (vc > nc.s23456789)); 65 66 nc = vload16(0, (__global DATA_TYPE *)offset(&src, -1, +1)); 67 out = select((DATA_TYPE)0, out, (vc > nc.s01234567) && (vc > nc.s12345678) && (vc > nc.s23456789)); 68 69 vstore8(out, 0, (__global DATA_TYPE *)dst.ptr); 70} 71