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Diffstat (limited to 'src/core/CL/cl_kernels/warp_perspective.cl')
-rw-r--r-- | src/core/CL/cl_kernels/warp_perspective.cl | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/src/core/CL/cl_kernels/warp_perspective.cl b/src/core/CL/cl_kernels/warp_perspective.cl new file mode 100644 index 0000000000..863b6c9e96 --- /dev/null +++ b/src/core/CL/cl_kernels/warp_perspective.cl @@ -0,0 +1,128 @@ +/* + * Copyright (c) 2016, 2017 ARM Limited. + * + * SPDX-License-Identifier: MIT + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to + * deal in the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or + * sell copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all + * copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ +#include "helpers.h" +#include "warp_helpers.h" + +/** Returns the perspective matrix */ +inline const float16 build_perspective_mtx() +{ + return (float16)(MAT0, MAT1, MAT2, MAT3, MAT4, MAT5, MAT6, MAT7, MAT8, 0, 0, 0, (float4)0); +} + +/** Transforms four 2D coordinates using the formula: + * + * x0 = M[1][1] * x + M[1][2] * y + M[1][3] + * y0 = M[2][1] * x + M[2][2] * y + M[2][3] + * z0 = M[3][1] * x + M[3][2] * y + M[3][3] + * + * (x0/z0,y0/z0) + * + * @param[in] coord 2D coordinate to transform. + * @param[in] mtx perspective matrix + * + * @return a vector float8 containing four 2D transformed values. + */ +inline const float8 apply_perspective_transform(const float2 coord, const float16 mtx) +{ + const float4 in_x_coords = (float4)(coord.s0, 1 + coord.s0, 2 + coord.s0, 3 + coord.s0); + // transform [z,z+1,z+2,z+3] + const float4 z = (float4)mad(in_x_coords, (float4)(mtx.s2), mad((float4)(coord.s1), (float4)(mtx.s5), (float4)(mtx.s8))); + // NOTE: Do not multiply x&y by 1.f/Z as this will result in loss of accuracy and mismatches with VX reference implementation + // transform [x,x+1,x+2,x+3] + const float4 new_x = (float4)mad(in_x_coords, (float4)(mtx.s0), mad((float4)(coord.s1), (float4)(mtx.s3), (float4)(mtx.s6))) / z; + // transform [y,y+1,y+2,y+3] + const float4 new_y = (float4)mad(in_x_coords, (float4)(mtx.s1), mad((float4)(coord.s1), (float4)(mtx.s4), (float4)(mtx.s7))) / z; + return (float8)(new_x.s0, new_y.s0, new_x.s1, new_y.s1, new_x.s2, new_y.s2, new_x.s3, new_y.s3); +} + +/** Performs perspective transformation on an image interpolating with the NEAREAST NEIGHBOUR method. Input and output are single channel U8. + * + * This kernel performs perspective transform with a 3x3 Matrix M with this method of pixel coordinate translation: + * x0 = M[1][1] * x + M[1][2] * y + M[1][3] + * y0 = M[2][1] * x + M[2][2] * y + M[2][3] + * z0 = M[3][1] * x + M[3][2] * y + M[3][3] + + * output(x,y) = input(x0/z0,y0/z0) + * + * @attention The matrix coefficients need to be passed at compile time:\n + * const char build_options [] = "-DMAT0=1 -DMAT1=2 -DMAT2=3 -DMAT3=4 -DMAT4=5 -DMAT5=6 -DMAT6=7 -DMAT7=8 -DMAT8=9"\n + * clBuildProgram( program, 0, NULL, build_options, NULL, NULL); + * + * @param[in] in_ptr Pointer to the source image. Supported data types: U8. + * @param[in] in_stride_x Stride of the source image in X dimension (in bytes) + * @param[in] in_step_x in_stride_x * number of elements along X processed per work item (in bytes) + * @param[in] in_stride_y Stride of the source image in Y dimension (in bytes) + * @param[in] in_step_y in_stride_y * number of elements along Y processed per work item (in bytes) + * @param[in] in_offset_first_element_in_bytes Offset of the first element in the source image + * @param[out] out_ptr Pointer to the destination image. Supported data types: U8. + * @param[in] out_stride_x Stride of the destination image in X dimension (in bytes) + * @param[in] out_step_x out_stride_x * number of elements along X processed per work item (in bytes) + * @param[in] out_stride_y Stride of the destination image in Y dimension (in bytes) + * @param[in] out_step_y out_stride_y * number of elements along Y processed per work item (in bytes) + * @param[in] out_offset_first_element_in_bytes Offset of the first element in the destination image + * @param[in] width Width of the destination image + * @param[in] height Height of the destination image + */ +__kernel void warp_perspective_nearest_neighbour( + IMAGE_DECLARATION(in), + IMAGE_DECLARATION(out), + const int width, + const int height) +{ + Image in = CONVERT_TO_IMAGE_STRUCT_NO_STEP(in); + Image out = CONVERT_TO_IMAGE_STRUCT(out); + vstore4(read_texels4(&in, convert_int8(clamp_to_border(apply_perspective_transform(get_current_coords(), build_perspective_mtx()), width, height))), 0, out.ptr); +} + +/** Performs a perspective transform on an image interpolating with the BILINEAR method. Input and output are single channel U8. + * + * @attention The matrix coefficients need to be passed at compile time:\n + * const char build_options [] = "-DMAT0=1 -DMAT1=2 -DMAT2=3 -DMAT3=4 -DMAT4=5 -DMAT5=6 -DMAT6=7 -DMAT7=8 -DMAT8=9"\n + * clBuildProgram( program, 0, NULL, build_options, NULL, NULL); + * + * @param[in] in_ptr Pointer to the source image. Supported data types: U8. + * @param[in] in_stride_x Stride of the source image in X dimension (in bytes) + * @param[in] in_step_x in_stride_x * number of elements along X processed per work item (in bytes) + * @param[in] in_stride_y Stride of the source image in Y dimension (in bytes) + * @param[in] in_step_y in_stride_y * number of elements along Y processed per work item (in bytes) + * @param[in] in_offset_first_element_in_bytes Offset of the first element in the source image + * @param[out] out_ptr Pointer to the destination image. Supported data types: U8. + * @param[in] out_stride_x Stride of the destination image in X dimension (in bytes) + * @param[in] out_step_x out_stride_x * number of elements along X processed per work item (in bytes) + * @param[in] out_stride_y Stride of the destination image in Y dimension (in bytes) + * @param[in] out_step_y out_stride_y * number of elements along Y processed per work item (in bytes) + * @param[in] out_offset_first_element_in_bytes Offset of the first element in the destination image + * @param[in] width Width of the destination image + * @param[in] height Height of the destination image + */ +__kernel void warp_perspective_bilinear( + IMAGE_DECLARATION(in), + IMAGE_DECLARATION(out), + const int width, + const int height) +{ + Image in = CONVERT_TO_IMAGE_STRUCT_NO_STEP(in); + Image out = CONVERT_TO_IMAGE_STRUCT(out); + vstore4(bilinear_interpolate(&in, clamp_to_border(apply_perspective_transform(get_current_coords(), build_perspective_mtx()), width, height), width, height), 0, out.ptr); +} |