opencv/modules/imgproc/src/opencl/canny.cl
2014-03-24 13:02:54 +04:00

563 lines
22 KiB
Common Lisp

/*M///////////////////////////////////////////////////////////////////////////////////////
//
// IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
//
// By downloading, copying, installing or using the software you agree to this license.
// If you do not agree to this license, do not download, install,
// copy or use the software.
//
//
// License Agreement
// For Open Source Computer Vision Library
//
// Copyright (C) 2010-2012, Multicoreware, Inc., all rights reserved.
// Copyright (C) 2010-2012, Advanced Micro Devices, Inc., all rights reserved.
// Third party copyrights are property of their respective owners.
//
// @Authors
// Peng Xiao, pengxiao@multicorewareinc.com
//
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
//
// * Redistribution's of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
//
// * Redistribution's in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
//
// * The name of the copyright holders may not be used to endorse or promote products
// derived from this software without specific prior written permission.
//
// This software is provided by the copyright holders and contributors as is and
// any express or implied warranties, including, but not limited to, the implied
// warranties of merchantability and fitness for a particular purpose are disclaimed.
// In no event shall the Intel Corporation or contributors be liable for any direct,
// indirect, incidental, special, exemplary, or consequential damages
// (including, but not limited to, procurement of substitute goods or services;
// loss of use, data, or profits; or business interruption) however caused
// and on any theory of liability, whether in contract, strict liability,
// or tort (including negligence or otherwise) arising in any way out of
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//
//M*/
#ifdef OP_SOBEL
#if cn != 3
#define loadpix(addr) convertToIntT(*(__global const ucharT *)(addr))
#define storepix(val, addr) *(__global shortT *)(addr) = convertToShortT(val)
#define shortSize (int)sizeof(shortT)
#else
#define loadpix(addr) convertToIntT(vload3(0, (__global const uchar *)(addr)))
#define storepix(val, addr) vstore3(convertToShortT(val), 0, (__global short *)(addr))
#define shortSize (int)sizeof(short) * cn
#endif
// Smoothing perpendicular to the derivative direction with a triangle filter
// only support 3x3 Sobel kernel
// h (-1) = 1, h (0) = 2, h (1) = 1
// h'(-1) = -1, h'(0) = 0, h'(1) = 1
// thus sobel 2D operator can be calculated as:
// h'(x, y) = h'(x)h(y) for x direction
//
// src input 8bit single channel image data
// dx_buf output dx buffer
// dy_buf output dy buffer
__kernel void calcSobelRowPass(__global const uchar * src, int src_step, int src_offset, int rows, int cols,
__global uchar * dx_buf, int dx_buf_step, int dx_buf_offset,
__global uchar * dy_buf, int dy_buf_step, int dy_buf_offset)
{
int gidx = get_global_id(0);
int gidy = get_global_id(1);
int lidx = get_local_id(0);
int lidy = get_local_id(1);
__local intT smem[16][18];
smem[lidy][lidx + 1] = loadpix(src + mad24(src_step, min(gidy, rows - 1), mad24(gidx, cn, src_offset)));
if (lidx == 0)
{
smem[lidy][0] = loadpix(src + mad24(src_step, min(gidy, rows - 1), mad24(max(gidx - 1, 0), cn, src_offset)));
smem[lidy][17] = loadpix(src + mad24(src_step, min(gidy, rows - 1), mad24(min(gidx + 16, cols - 1), cn, src_offset)));
}
barrier(CLK_LOCAL_MEM_FENCE);
if (gidy < rows && gidx < cols)
{
storepix(smem[lidy][lidx + 2] - smem[lidy][lidx],
dx_buf + mad24(gidy, dx_buf_step, mad24(gidx, shortSize, dx_buf_offset)));
storepix(mad24(2, smem[lidy][lidx + 1], smem[lidy][lidx] + smem[lidy][lidx + 2]),
dy_buf + mad24(gidy, dy_buf_step, mad24(gidx, shortSize, dy_buf_offset)));
}
}
#elif defined OP_MAG_BUF || defined OP_MAG
inline intT calc(shortT x, shortT y)
{
#ifdef L2GRAD
intT intx = convertToIntT(x), inty = convertToIntT(y);
return intx * intx + inty * inty;
#else
return convertToIntT( (x >= (shortT)(0) ? x : -x) + (y >= (shortT)(0) ? y : -y) );
#endif
}
#ifdef OP_MAG
// calculate the magnitude of the filter pass combining both x and y directions
// This is the non-buffered version(non-3x3 sobel)
//
// dx_buf dx buffer, calculated from calcSobelRowPass
// dy_buf dy buffer, calculated from calcSobelRowPass
// dx direvitive in x direction output
// dy direvitive in y direction output
// mag magnitude direvitive of xy output
__kernel void calcMagnitude(__global const uchar * dxptr, int dx_step, int dx_offset,
__global const uchar * dyptr, int dy_step, int dy_offset,
__global uchar * magptr, int mag_step, int mag_offset, int rows, int cols)
{
int x = get_global_id(0);
int y = get_global_id(1);
if (y < rows && x < cols)
{
int dx_index = mad24(dx_step, y, mad24(x, (int)sizeof(short) * cn, dx_offset));
int dy_index = mad24(dy_step, y, mad24(x, (int)sizeof(short) * cn, dy_offset));
int mag_index = mad24(mag_step, y + 1, mad24(x + 1, (int)sizeof(int), mag_offset));
__global short * dx = (__global short *)(dxptr + dx_index);
__global short * dy = (__global short *)(dyptr + dy_index);
__global int * mag = (__global int *)(magptr + mag_index);
int cmag = calc(dx[0], dy[0]);
#if cn > 1
short cx = dx[0], cy = dy[0];
int pmag;
#pragma unroll
for (int i = 1; i < cn; ++i)
{
pmag = calc(dx[i], dy[i]);
if (pmag > cmag)
cmag = pmag, cx = dx[i], cy = dy[i];
}
dx[0] = cx, dy[0] = cy;
#endif
mag[0] = cmag;
}
}
#elif defined OP_MAG_BUF
#if cn != 3
#define loadpix(addr) *(__global const shortT *)(addr)
#define shortSize (int)sizeof(shortT)
#else
#define loadpix(addr) vload3(0, (__global const short *)(addr))
#define shortSize (int)sizeof(short)*cn
#endif
// calculate the magnitude of the filter pass combining both x and y directions
// This is the buffered version(3x3 sobel)
//
// dx_buf dx buffer, calculated from calcSobelRowPass
// dy_buf dy buffer, calculated from calcSobelRowPass
// dx direvitive in x direction output
// dy direvitive in y direction output
// mag magnitude direvitive of xy output
__kernel void calcMagnitude_buf(__global const uchar * dx_buf, int dx_buf_step, int dx_buf_offset,
__global const uchar * dy_buf, int dy_buf_step, int dy_buf_offset,
__global uchar * dx, int dx_step, int dx_offset,
__global uchar * dy, int dy_step, int dy_offset,
__global uchar * mag, int mag_step, int mag_offset, int rows, int cols)
{
int gidx = get_global_id(0);
int gidy = get_global_id(1);
int lidx = get_local_id(0);
int lidy = get_local_id(1);
__local shortT sdx[18][16];
__local shortT sdy[18][16];
sdx[lidy + 1][lidx] = loadpix(dx_buf + mad24(min(gidy, rows - 1), dx_buf_step, mad24(gidx, shortSize, dx_buf_offset)));
sdy[lidy + 1][lidx] = loadpix(dy_buf + mad24(min(gidy, rows - 1), dy_buf_step, mad24(gidx, shortSize, dy_buf_offset)));
if (lidy == 0)
{
sdx[0][lidx] = loadpix(dx_buf + mad24(clamp(gidy - 1, 0, rows - 1), dx_buf_step, mad24(gidx, shortSize, dx_buf_offset)));
sdx[17][lidx] = loadpix(dx_buf + mad24(min(gidy + 16, rows - 1), dx_buf_step, mad24(gidx, shortSize, dx_buf_offset)));
sdy[0][lidx] = loadpix(dy_buf + mad24(clamp(gidy - 1, 0, rows - 1), dy_buf_step, mad24(gidx, shortSize, dy_buf_offset)));
sdy[17][lidx] = loadpix(dy_buf + mad24(min(gidy + 16, rows - 1), dy_buf_step, mad24(gidx, shortSize, dy_buf_offset)));
}
barrier(CLK_LOCAL_MEM_FENCE);
if (gidx < cols && gidy < rows)
{
shortT x = sdx[lidy + 1][lidx] * (shortT)(2) + sdx[lidy][lidx] + sdx[lidy + 2][lidx];
shortT y = -sdy[lidy][lidx] + sdy[lidy + 2][lidx];
#if cn == 1
*(__global short *)(dx + mad24(gidy, dx_step, mad24(gidx, shortSize, dx_offset))) = x;
*(__global short *)(dy + mad24(gidy, dy_step, mad24(gidx, shortSize, dy_offset))) = y;
*(__global int *)(mag + mad24(gidy + 1, mag_step, mad24(gidx + 1, (int)sizeof(int), mag_offset))) = calc(x, y);
#elif cn == 3
intT magv = calc(x, y);
short cx = x.x, cy = y.x;
int cmag = magv.x;
if (cmag < magv.y)
cx = x.y, cy = y.y, cmag = magv.y;
if (cmag < magv.z)
cx = x.z, cy = y.z, cmag = magv.z;
*(__global short *)(dx + mad24(gidy, dx_step, mad24(gidx, shortSize, dx_offset))) = cx;
*(__global short *)(dy + mad24(gidy, dy_step, mad24(gidx, shortSize, dy_offset))) = cy;
*(__global int *)(mag + mad24(gidy + 1, mag_step, mad24(gidx + 1, (int)sizeof(int), mag_offset))) = cmag;
#endif
}
}
#endif
#elif defined OP_MAP
//////////////////////////////////////////////////////////////////////////////////////////
// 0.4142135623730950488016887242097 is tan(22.5)
#define CANNY_SHIFT 15
#define TG22 (int)(0.4142135623730950488016887242097f*(1<<CANNY_SHIFT) + 0.5f)
// First pass of edge detection and non-maximum suppression
// edgetype is set to for each pixel:
// 0 - below low thres, not an edge
// 1 - maybe an edge
// 2 - is an edge, either magnitude is greater than high thres, or
// Given estimates of the image gradients, a search is then carried out
// to determine if the gradient magnitude assumes a local maximum in the gradient direction.
// if the rounded gradient angle is zero degrees (i.e. the edge is in the north-south direction) the point will be considered to be on the edge if its gradient magnitude is greater than the magnitudes in the west and east directions,
// if the rounded gradient angle is 90 degrees (i.e. the edge is in the east-west direction) the point will be considered to be on the edge if its gradient magnitude is greater than the magnitudes in the north and south directions,
// if the rounded gradient angle is 135 degrees (i.e. the edge is in the north east-south west direction) the point will be considered to be on the edge if its gradient magnitude is greater than the magnitudes in the north west and south east directions,
// if the rounded gradient angle is 45 degrees (i.e. the edge is in the north west-south east direction)the point will be considered to be on the edge if its gradient magnitude is greater than the magnitudes in the north east and south west directions.
//
// dx, dy direvitives of x and y direction
// mag magnitudes calculated from calcMagnitude function
// map output containing raw edge types
__kernel void calcMap(__global const uchar * dx, int dx_step, int dx_offset,
__global const uchar * dy, int dy_step, int dy_offset,
__global const uchar * mag, int mag_step, int mag_offset,
__global uchar * map, int map_step, int map_offset,
int rows, int cols, int low_thresh, int high_thresh)
{
__local int smem[18][18];
int gidx = get_global_id(0);
int gidy = get_global_id(1);
int lidx = get_local_id(0);
int lidy = get_local_id(1);
int grp_idx = get_global_id(0) & 0xFFFFF0;
int grp_idy = get_global_id(1) & 0xFFFFF0;
int tid = mad24(lidy, 16, lidx);
int lx = tid % 18;
int ly = tid / 18;
mag += mag_offset;
if (ly < 14)
smem[ly][lx] = *(__global const int *)(mag +
mad24(mag_step, min(grp_idy + ly, rows - 1), (int)sizeof(int) * (grp_idx + lx)));
if (ly < 4 && grp_idy + ly + 14 <= rows && grp_idx + lx <= cols)
smem[ly + 14][lx] = *(__global const int *)(mag +
mad24(mag_step, min(grp_idy + ly + 14, rows - 1), (int)sizeof(int) * (grp_idx + lx)));
barrier(CLK_LOCAL_MEM_FENCE);
if (gidy < rows && gidx < cols)
{
// 0 - the pixel can not belong to an edge
// 1 - the pixel might belong to an edge
// 2 - the pixel does belong to an edge
int edge_type = 0;
int m = smem[lidy + 1][lidx + 1];
if (m > low_thresh)
{
short xs = *(__global const short *)(dx + mad24(gidy, dx_step, mad24(gidx, (int)sizeof(short) * cn, dx_offset)));
short ys = *(__global const short *)(dy + mad24(gidy, dy_step, mad24(gidx, (int)sizeof(short) * cn, dy_offset)));
int x = abs(xs), y = abs(ys);
int tg22x = x * TG22;
y <<= CANNY_SHIFT;
if (y < tg22x)
{
if (m > smem[lidy + 1][lidx] && m >= smem[lidy + 1][lidx + 2])
edge_type = 1 + (int)(m > high_thresh);
}
else
{
int tg67x = tg22x + (x << (1 + CANNY_SHIFT));
if (y > tg67x)
{
if (m > smem[lidy][lidx + 1]&& m >= smem[lidy + 2][lidx + 1])
edge_type = 1 + (int)(m > high_thresh);
}
else
{
int s = (xs ^ ys) < 0 ? -1 : 1;
if (m > smem[lidy][lidx + 1 - s]&& m > smem[lidy + 2][lidx + 1 + s])
edge_type = 1 + (int)(m > high_thresh);
}
}
}
*(__global int *)(map + mad24(map_step, gidy + 1, mad24(gidx + 1, (int)sizeof(int), + map_offset))) = edge_type;
}
}
#undef CANNY_SHIFT
#undef TG22
#elif defined OP_HYST_LOCAL
struct PtrStepSz
{
__global uchar * ptr;
int step, rows, cols;
};
inline int get(struct PtrStepSz data, int y, int x)
{
return *(__global int *)(data.ptr + mad24(data.step, y + 1, (int)sizeof(int) * (x + 1)));
}
inline void set(struct PtrStepSz data, int y, int x, int value)
{
*(__global int *)(data.ptr + mad24(data.step, y + 1, (int)sizeof(int) * (x + 1))) = value;
}
// perform Hysteresis for pixel whose edge type is 1
//
// If candidate pixel (edge type is 1) has a neighbour pixel (in 3x3 area) with type 2, it is believed to be part of an edge and
// marked as edge. Each thread will iterate for 16 times to connect local edges.
// Candidate pixel being identified as edge will then be tested if there is nearby potiential edge points. If there is, counter will
// be incremented by 1 and the point location is stored. These potiential candidates will be processed further in next kernel.
//
// map raw edge type results calculated from calcMap.
// stack the potiential edge points found in this kernel call
// counter the number of potiential edge points
__kernel void edgesHysteresisLocal(__global uchar * map_ptr, int map_step, int map_offset,
__global ushort2 * st, __global unsigned int * counter,
int rows, int cols)
{
struct PtrStepSz map = { map_ptr + map_offset, map_step, rows + 1, cols + 1 };
__local int smem[18][18];
int2 blockIdx = (int2)(get_group_id(0), get_group_id(1));
int2 blockDim = (int2)(get_local_size(0), get_local_size(1));
int2 threadIdx = (int2)(get_local_id(0), get_local_id(1));
const int x = blockIdx.x * blockDim.x + threadIdx.x;
const int y = blockIdx.y * blockDim.y + threadIdx.y;
smem[threadIdx.y + 1][threadIdx.x + 1] = x < map.cols && y < map.rows ? get(map, y, x) : 0;
if (threadIdx.y == 0)
smem[0][threadIdx.x + 1] = x < map.cols ? get(map, y - 1, x) : 0;
if (threadIdx.y == blockDim.y - 1)
smem[blockDim.y + 1][threadIdx.x + 1] = y + 1 < map.rows ? get(map, y + 1, x) : 0;
if (threadIdx.x == 0)
smem[threadIdx.y + 1][0] = y < map.rows ? get(map, y, x - 1) : 0;
if (threadIdx.x == blockDim.x - 1)
smem[threadIdx.y + 1][blockDim.x + 1] = x + 1 < map.cols && y < map.rows ? get(map, y, x + 1) : 0;
if (threadIdx.x == 0 && threadIdx.y == 0)
smem[0][0] = y > 0 && x > 0 ? get(map, y - 1, x - 1) : 0;
if (threadIdx.x == blockDim.x - 1 && threadIdx.y == 0)
smem[0][blockDim.x + 1] = y > 0 && x + 1 < map.cols ? get(map, y - 1, x + 1) : 0;
if (threadIdx.x == 0 && threadIdx.y == blockDim.y - 1)
smem[blockDim.y + 1][0] = y + 1 < map.rows && x > 0 ? get(map, y + 1, x - 1) : 0;
if (threadIdx.x == blockDim.x - 1 && threadIdx.y == blockDim.y - 1)
smem[blockDim.y + 1][blockDim.x + 1] = y + 1 < map.rows && x + 1 < map.cols ? get(map, y + 1, x + 1) : 0;
barrier(CLK_LOCAL_MEM_FENCE);
if (x >= cols || y >= rows)
return;
int n;
#pragma unroll
for (int k = 0; k < 16; ++k)
{
n = 0;
if (smem[threadIdx.y + 1][threadIdx.x + 1] == 1)
{
n += smem[threadIdx.y ][threadIdx.x ] == 2;
n += smem[threadIdx.y ][threadIdx.x + 1] == 2;
n += smem[threadIdx.y ][threadIdx.x + 2] == 2;
n += smem[threadIdx.y + 1][threadIdx.x ] == 2;
n += smem[threadIdx.y + 1][threadIdx.x + 2] == 2;
n += smem[threadIdx.y + 2][threadIdx.x ] == 2;
n += smem[threadIdx.y + 2][threadIdx.x + 1] == 2;
n += smem[threadIdx.y + 2][threadIdx.x + 2] == 2;
}
if (n > 0)
smem[threadIdx.y + 1][threadIdx.x + 1] = 2;
}
const int e = smem[threadIdx.y + 1][threadIdx.x + 1];
set(map, y, x, e);
n = 0;
if (e == 2)
{
n += smem[threadIdx.y ][threadIdx.x ] == 1;
n += smem[threadIdx.y ][threadIdx.x + 1] == 1;
n += smem[threadIdx.y ][threadIdx.x + 2] == 1;
n += smem[threadIdx.y + 1][threadIdx.x ] == 1;
n += smem[threadIdx.y + 1][threadIdx.x + 2] == 1;
n += smem[threadIdx.y + 2][threadIdx.x ] == 1;
n += smem[threadIdx.y + 2][threadIdx.x + 1] == 1;
n += smem[threadIdx.y + 2][threadIdx.x + 2] == 1;
}
if (n > 0)
{
const int ind = atomic_inc(counter);
st[ind] = (ushort2)(x + 1, y + 1);
}
}
#elif defined OP_HYST_GLOBAL
__constant int c_dx[8] = {-1, 0, 1, -1, 1, -1, 0, 1};
__constant int c_dy[8] = {-1, -1, -1, 0, 0, 1, 1, 1};
#define stack_size 512
#define map_index mad24(map_step, pos.y, pos.x * (int)sizeof(int))
__kernel void edgesHysteresisGlobal(__global uchar * map, int map_step, int map_offset,
__global ushort2 * st1, __global ushort2 * st2, __global int * counter,
int rows, int cols, int count)
{
map += map_offset;
int lidx = get_local_id(0);
int grp_idx = get_group_id(0);
int grp_idy = get_group_id(1);
__local unsigned int s_counter, s_ind;
__local ushort2 s_st[stack_size];
if (lidx == 0)
s_counter = 0;
barrier(CLK_LOCAL_MEM_FENCE);
int ind = mad24(grp_idy, (int)get_local_size(0), grp_idx);
if (ind < count)
{
ushort2 pos = st1[ind];
if (lidx < 8)
{
pos.x += c_dx[lidx];
pos.y += c_dy[lidx];
if (pos.x > 0 && pos.x <= cols && pos.y > 0 && pos.y <= rows && *(__global int *)(map + map_index) == 1)
{
*(__global int *)(map + map_index) = 2;
ind = atomic_inc(&s_counter);
s_st[ind] = pos;
}
}
barrier(CLK_LOCAL_MEM_FENCE);
while (s_counter > 0 && s_counter <= stack_size - get_local_size(0))
{
const int subTaskIdx = lidx >> 3;
const int portion = min(s_counter, (uint)(get_local_size(0)>> 3));
if (subTaskIdx < portion)
pos = s_st[s_counter - 1 - subTaskIdx];
barrier(CLK_LOCAL_MEM_FENCE);
if (lidx == 0)
s_counter -= portion;
barrier(CLK_LOCAL_MEM_FENCE);
if (subTaskIdx < portion)
{
pos.x += c_dx[lidx & 7];
pos.y += c_dy[lidx & 7];
if (pos.x > 0 && pos.x <= cols && pos.y > 0 && pos.y <= rows && *(__global int *)(map + map_index) == 1)
{
*(__global int *)(map + map_index) = 2;
ind = atomic_inc(&s_counter);
s_st[ind] = pos;
}
}
barrier(CLK_LOCAL_MEM_FENCE);
}
if (s_counter > 0)
{
if (lidx == 0)
{
ind = atomic_add(counter, s_counter);
s_ind = ind - s_counter;
}
barrier(CLK_LOCAL_MEM_FENCE);
ind = s_ind;
for (int i = lidx; i < (int)s_counter; i += get_local_size(0))
st2[ind + i] = s_st[i];
}
}
}
#undef map_index
#undef stack_size
#elif defined OP_EDGES
// Get the edge result. egde type of value 2 will be marked as an edge point and set to 255. Otherwise 0.
// map edge type mappings
// dst edge output
__kernel void getEdges(__global const uchar * mapptr, int map_step, int map_offset,
__global uchar * dst, int dst_step, int dst_offset, int rows, int cols)
{
int x = get_global_id(0);
int y = get_global_id(1);
if (y < rows && x < cols)
{
int map_index = mad24(map_step, y + 1, mad24(x + 1, (int)sizeof(int), map_offset));
int dst_index = mad24(dst_step, y, x + dst_offset);
__global const int * map = (__global const int *)(mapptr + map_index);
dst[dst_index] = (uchar)(-(map[0] >> 1));
}
}
#endif