<tr style="height: 56px;">
<td style="padding-left: 0.5em;">
<div id="projectname">ARM Compute Library
-  <span id="projectnumber">17.03.1</span>
+  <span id="projectnumber">17.04</span>
</div>
</td>
</tr>
<div class="title">canny.cl</div> </div>
</div><!--header-->
<div class="contents">
-<a href="canny_8cl.xhtml">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span> <span class="comment">/*</span></div><div class="line"><a name="l00002"></a><span class="lineno"> 2</span> <span class="comment"> * Copyright (c) 2017 ARM Limited.</span></div><div class="line"><a name="l00003"></a><span class="lineno"> 3</span> <span class="comment"> *</span></div><div class="line"><a name="l00004"></a><span class="lineno"> 4</span> <span class="comment"> * SPDX-License-Identifier: MIT</span></div><div class="line"><a name="l00005"></a><span class="lineno"> 5</span> <span class="comment"> *</span></div><div class="line"><a name="l00006"></a><span class="lineno"> 6</span> <span class="comment"> * Permission is hereby granted, free of charge, to any person obtaining a copy</span></div><div class="line"><a name="l00007"></a><span class="lineno"> 7</span> <span class="comment"> * of this software and associated documentation files (the "Software"), to</span></div><div class="line"><a name="l00008"></a><span class="lineno"> 8</span> <span class="comment"> * deal in the Software without restriction, including without limitation the</span></div><div class="line"><a name="l00009"></a><span class="lineno"> 9</span> <span class="comment"> * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or</span></div><div class="line"><a name="l00010"></a><span class="lineno"> 10</span> <span class="comment"> * sell copies of the Software, and to permit persons to whom the Software is</span></div><div class="line"><a name="l00011"></a><span class="lineno"> 11</span> <span class="comment"> * furnished to do so, subject to the following conditions:</span></div><div class="line"><a name="l00012"></a><span class="lineno"> 12</span> <span class="comment"> *</span></div><div class="line"><a name="l00013"></a><span class="lineno"> 13</span> <span class="comment"> * The above copyright notice and this permission notice shall be included in all</span></div><div class="line"><a name="l00014"></a><span class="lineno"> 14</span> <span class="comment"> * copies or substantial portions of the Software.</span></div><div class="line"><a name="l00015"></a><span class="lineno"> 15</span> <span class="comment"> *</span></div><div class="line"><a name="l00016"></a><span class="lineno"> 16</span> <span class="comment"> * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR</span></div><div class="line"><a name="l00017"></a><span class="lineno"> 17</span> <span class="comment"> * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,</span></div><div class="line"><a name="l00018"></a><span class="lineno"> 18</span> <span class="comment"> * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE</span></div><div class="line"><a name="l00019"></a><span class="lineno"> 19</span> <span class="comment"> * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER</span></div><div class="line"><a name="l00020"></a><span class="lineno"> 20</span> <span class="comment"> * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,</span></div><div class="line"><a name="l00021"></a><span class="lineno"> 21</span> <span class="comment"> * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE</span></div><div class="line"><a name="l00022"></a><span class="lineno"> 22</span> <span class="comment"> * SOFTWARE.</span></div><div class="line"><a name="l00023"></a><span class="lineno"> 23</span> <span class="comment"> */</span></div><div class="line"><a name="l00024"></a><span class="lineno"> 24</span> <span class="preprocessor">#include "<a class="code" href="helpers_8h.xhtml">helpers.h</a>"</span></div><div class="line"><a name="l00025"></a><span class="lineno"> 25</span> </div><div class="line"><a name="l00057"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#a92f95668118a1bc6ef0eed965dfd570f"> 57</a></span> __kernel <span class="keywordtype">void</span> <a class="code" href="canny_8cl.xhtml#a92f95668118a1bc6ef0eed965dfd570f">combine_gradients_L1</a>(</div><div class="line"><a name="l00058"></a><span class="lineno"> 58</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(src1),</div><div class="line"><a name="l00059"></a><span class="lineno"> 59</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(src2),</div><div class="line"><a name="l00060"></a><span class="lineno"> 60</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(grad),</div><div class="line"><a name="l00061"></a><span class="lineno"> 61</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(angle))</div><div class="line"><a name="l00062"></a><span class="lineno"> 62</span> {</div><div class="line"><a name="l00063"></a><span class="lineno"> 63</span>  <span class="comment">// Construct images</span></div><div class="line"><a name="l00064"></a><span class="lineno"> 64</span>  <a class="code" href="struct_image.xhtml">Image</a> src1 = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(src1);</div><div class="line"><a name="l00065"></a><span class="lineno"> 65</span>  <a class="code" href="struct_image.xhtml">Image</a> src2 = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(src2);</div><div class="line"><a name="l00066"></a><span class="lineno"> 66</span>  <a class="code" href="struct_image.xhtml">Image</a> grad = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(grad);</div><div class="line"><a name="l00067"></a><span class="lineno"> 67</span>  <a class="code" href="struct_image.xhtml">Image</a> angle = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(angle);</div><div class="line"><a name="l00068"></a><span class="lineno"> 68</span> </div><div class="line"><a name="l00069"></a><span class="lineno"> 69</span>  <span class="comment">// Load sobel horizontal and vertical values</span></div><div class="line"><a name="l00070"></a><span class="lineno"> 70</span>  <a class="code" href="helpers_8h.xhtml#a36f754c05b6fddf6df0d8d0a74f8159f">VEC_DATA_TYPE</a>(DATA_TYPE_IN, 4)</div><div class="line"><a name="l00071"></a><span class="lineno"> 71</span>  h = vload4(0, (__global DATA_TYPE_IN *)src1.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>);</div><div class="line"><a name="l00072"></a><span class="lineno"> 72</span>  <a class="code" href="helpers_8h.xhtml#a36f754c05b6fddf6df0d8d0a74f8159f">VEC_DATA_TYPE</a>(DATA_TYPE_IN, 4)</div><div class="line"><a name="l00073"></a><span class="lineno"> 73</span>  v = vload4(0, (__global DATA_TYPE_IN *)src2.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>);</div><div class="line"><a name="l00074"></a><span class="lineno"> 74</span> </div><div class="line"><a name="l00075"></a><span class="lineno"> 75</span>  <span class="comment">/* Calculate the gradient, using level 1 normalisation method */</span></div><div class="line"><a name="l00076"></a><span class="lineno"> 76</span>  <a class="code" href="helpers_8h.xhtml#a36f754c05b6fddf6df0d8d0a74f8159f">VEC_DATA_TYPE</a>(<a class="code" href="convolution3x3_8cl.xhtml#ac06f3e24d3fffd3c465d8b2a6e7c985e">DATA_TYPE_OUT</a>, 4)</div><div class="line"><a name="l00077"></a><span class="lineno"> 77</span>  m = <a class="code" href="helpers_8h.xhtml#a23fb01b6f3453cc0e48a026fd44f6acd">CONVERT_SAT</a>((abs(h) + abs(v)), <a class="code" href="helpers_8h.xhtml#a36f754c05b6fddf6df0d8d0a74f8159f">VEC_DATA_TYPE</a>(<a class="code" href="convolution3x3_8cl.xhtml#ac06f3e24d3fffd3c465d8b2a6e7c985e">DATA_TYPE_OUT</a>, 4));</div><div class="line"><a name="l00078"></a><span class="lineno"> 78</span> </div><div class="line"><a name="l00079"></a><span class="lineno"> 79</span>  <span class="comment">/* Calculate the angle */</span></div><div class="line"><a name="l00080"></a><span class="lineno"> 80</span>  float4 p = atan2pi(convert_float4(v), convert_float4(h));</div><div class="line"><a name="l00081"></a><span class="lineno"> 81</span> </div><div class="line"><a name="l00082"></a><span class="lineno"> 82</span>  <span class="comment">/* Remap angle to range [0, 256) */</span></div><div class="line"><a name="l00083"></a><span class="lineno"> 83</span>  p = select(p, p + 2, p < 0.0f) * 128.0f;</div><div class="line"><a name="l00084"></a><span class="lineno"> 84</span> </div><div class="line"><a name="l00085"></a><span class="lineno"> 85</span>  <span class="comment">/* Store results */</span></div><div class="line"><a name="l00086"></a><span class="lineno"> 86</span>  vstore4(m, 0, (__global <a class="code" href="convolution3x3_8cl.xhtml#ac06f3e24d3fffd3c465d8b2a6e7c985e">DATA_TYPE_OUT</a> *)grad.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>);</div><div class="line"><a name="l00087"></a><span class="lineno"> 87</span>  vstore4(convert_uchar4_sat_rte(p), 0, angle.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>);</div><div class="line"><a name="l00088"></a><span class="lineno"> 88</span> }</div><div class="line"><a name="l00089"></a><span class="lineno"> 89</span> </div><div class="line"><a name="l00121"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#a7046357526e2f95a34e3ffa217752d9f"> 121</a></span> __kernel <span class="keywordtype">void</span> <a class="code" href="canny_8cl.xhtml#a7046357526e2f95a34e3ffa217752d9f">combine_gradients_L2</a>(</div><div class="line"><a name="l00122"></a><span class="lineno"> 122</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(src1),</div><div class="line"><a name="l00123"></a><span class="lineno"> 123</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(src2),</div><div class="line"><a name="l00124"></a><span class="lineno"> 124</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(grad),</div><div class="line"><a name="l00125"></a><span class="lineno"> 125</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(angle))</div><div class="line"><a name="l00126"></a><span class="lineno"> 126</span> {</div><div class="line"><a name="l00127"></a><span class="lineno"> 127</span>  <span class="comment">// Construct images</span></div><div class="line"><a name="l00128"></a><span class="lineno"> 128</span>  <a class="code" href="struct_image.xhtml">Image</a> src1 = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(src1);</div><div class="line"><a name="l00129"></a><span class="lineno"> 129</span>  <a class="code" href="struct_image.xhtml">Image</a> src2 = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(src2);</div><div class="line"><a name="l00130"></a><span class="lineno"> 130</span>  <a class="code" href="struct_image.xhtml">Image</a> grad = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(grad);</div><div class="line"><a name="l00131"></a><span class="lineno"> 131</span>  <a class="code" href="struct_image.xhtml">Image</a> angle = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(angle);</div><div class="line"><a name="l00132"></a><span class="lineno"> 132</span> </div><div class="line"><a name="l00133"></a><span class="lineno"> 133</span>  <span class="comment">// Load sobel horizontal and vertical values</span></div><div class="line"><a name="l00134"></a><span class="lineno"> 134</span>  float4 h = convert_float4(vload4(0, (__global DATA_TYPE_IN *)src1.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>));</div><div class="line"><a name="l00135"></a><span class="lineno"> 135</span>  float4 v = convert_float4(vload4(0, (__global DATA_TYPE_IN *)src2.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>));</div><div class="line"><a name="l00136"></a><span class="lineno"> 136</span> </div><div class="line"><a name="l00137"></a><span class="lineno"> 137</span>  <span class="comment">/* Calculate the gradient, using level 2 normalisation method */</span></div><div class="line"><a name="l00138"></a><span class="lineno"> 138</span>  float4 m = sqrt(h * h + v * v);</div><div class="line"><a name="l00139"></a><span class="lineno"> 139</span> </div><div class="line"><a name="l00140"></a><span class="lineno"> 140</span>  <span class="comment">/* Calculate the angle */</span></div><div class="line"><a name="l00141"></a><span class="lineno"> 141</span>  float4 p = atan2pi(v, h);</div><div class="line"><a name="l00142"></a><span class="lineno"> 142</span> </div><div class="line"><a name="l00143"></a><span class="lineno"> 143</span>  <span class="comment">/* Remap angle to range [0, 256) */</span></div><div class="line"><a name="l00144"></a><span class="lineno"> 144</span>  p = select(p, p + 2, p < 0.0f) * 128.0f;</div><div class="line"><a name="l00145"></a><span class="lineno"> 145</span> </div><div class="line"><a name="l00146"></a><span class="lineno"> 146</span>  <span class="comment">/* Store results */</span></div><div class="line"><a name="l00147"></a><span class="lineno"> 147</span>  vstore4(<a class="code" href="helpers_8h.xhtml#a28b2b123792a5b11a32cb05a6d327437">CONVERT_SAT_ROUND</a>(m, <a class="code" href="helpers_8h.xhtml#a36f754c05b6fddf6df0d8d0a74f8159f">VEC_DATA_TYPE</a>(<a class="code" href="convolution3x3_8cl.xhtml#ac06f3e24d3fffd3c465d8b2a6e7c985e">DATA_TYPE_OUT</a>, 4), rte), 0, (__global <a class="code" href="convolution3x3_8cl.xhtml#ac06f3e24d3fffd3c465d8b2a6e7c985e">DATA_TYPE_OUT</a> *)grad.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>);</div><div class="line"><a name="l00148"></a><span class="lineno"> 148</span>  vstore4(convert_uchar4_sat_rte(p), 0, angle.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>);</div><div class="line"><a name="l00149"></a><span class="lineno"> 149</span> }</div><div class="line"><a name="l00150"></a><span class="lineno"> 150</span> </div><div class="line"><a name="l00153"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#a65e45b2f8637f10dd14a427f37c2cd4c"> 153</a></span> __constant short4 <a class="code" href="canny_8cl.xhtml#a65e45b2f8637f10dd14a427f37c2cd4c">neighbours_coords</a>[] =</div><div class="line"><a name="l00154"></a><span class="lineno"> 154</span> {</div><div class="line"><a name="l00155"></a><span class="lineno"> 155</span>  { -1, 0, 1, 0 }, <span class="comment">// 0</span></div><div class="line"><a name="l00156"></a><span class="lineno"> 156</span>  { -1, 1, 1, -1 }, <span class="comment">// 45</span></div><div class="line"><a name="l00157"></a><span class="lineno"> 157</span>  { 0, 1, 0, -1 }, <span class="comment">// 90</span></div><div class="line"><a name="l00158"></a><span class="lineno"> 158</span>  { 1, 1, -1, -1 }, <span class="comment">// 135</span></div><div class="line"><a name="l00159"></a><span class="lineno"> 159</span>  { 1, 0, -1, 0 }, <span class="comment">// 180</span></div><div class="line"><a name="l00160"></a><span class="lineno"> 160</span>  { 1, -1, -1, 1 }, <span class="comment">// 225</span></div><div class="line"><a name="l00161"></a><span class="lineno"> 161</span>  { 0, 1, 0, -1 }, <span class="comment">// 270</span></div><div class="line"><a name="l00162"></a><span class="lineno"> 162</span>  { -1, -1, 1, 1 }, <span class="comment">// 315</span></div><div class="line"><a name="l00163"></a><span class="lineno"> 163</span>  { -1, 0, 1, 0 }, <span class="comment">// 360</span></div><div class="line"><a name="l00164"></a><span class="lineno"> 164</span> };</div><div class="line"><a name="l00165"></a><span class="lineno"> 165</span> </div><div class="line"><a name="l00191"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#a8c233c75ee1010bcec8601d559f4be68"> 191</a></span> __kernel <span class="keywordtype">void</span> <a class="code" href="canny_8cl.xhtml#a8c233c75ee1010bcec8601d559f4be68">suppress_non_maximum</a>(</div><div class="line"><a name="l00192"></a><span class="lineno"> 192</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(grad),</div><div class="line"><a name="l00193"></a><span class="lineno"> 193</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(angle),</div><div class="line"><a name="l00194"></a><span class="lineno"> 194</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(non_max),</div><div class="line"><a name="l00195"></a><span class="lineno"> 195</span>  uint lower_thr)</div><div class="line"><a name="l00196"></a><span class="lineno"> 196</span> {</div><div class="line"><a name="l00197"></a><span class="lineno"> 197</span>  <span class="comment">// Construct images</span></div><div class="line"><a name="l00198"></a><span class="lineno"> 198</span>  <a class="code" href="struct_image.xhtml">Image</a> grad = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(grad);</div><div class="line"><a name="l00199"></a><span class="lineno"> 199</span>  <a class="code" href="struct_image.xhtml">Image</a> angle = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(angle);</div><div class="line"><a name="l00200"></a><span class="lineno"> 200</span>  <a class="code" href="struct_image.xhtml">Image</a> non_max = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(non_max);</div><div class="line"><a name="l00201"></a><span class="lineno"> 201</span> </div><div class="line"><a name="l00202"></a><span class="lineno"> 202</span>  <span class="comment">// Get gradient and angle</span></div><div class="line"><a name="l00203"></a><span class="lineno"> 203</span>  DATA_TYPE_IN gradient = *((__global DATA_TYPE_IN *)grad.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>);</div><div class="line"><a name="l00204"></a><span class="lineno"> 204</span>  uchar an = convert_ushort(*angle.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>);</div><div class="line"><a name="l00205"></a><span class="lineno"> 205</span> </div><div class="line"><a name="l00206"></a><span class="lineno"> 206</span>  <span class="keywordflow">if</span>(gradient <= lower_thr)</div><div class="line"><a name="l00207"></a><span class="lineno"> 207</span>  {</div><div class="line"><a name="l00208"></a><span class="lineno"> 208</span>  <span class="keywordflow">return</span>;</div><div class="line"><a name="l00209"></a><span class="lineno"> 209</span>  }</div><div class="line"><a name="l00210"></a><span class="lineno"> 210</span> </div><div class="line"><a name="l00211"></a><span class="lineno"> 211</span>  <span class="comment">// Divide the whole round into 8 directions</span></div><div class="line"><a name="l00212"></a><span class="lineno"> 212</span>  uchar ang = 127 - an;</div><div class="line"><a name="l00213"></a><span class="lineno"> 213</span>  <a class="code" href="convolution3x3_8cl.xhtml#ac06f3e24d3fffd3c465d8b2a6e7c985e">DATA_TYPE_OUT</a> q_an = (ang + 16) >> 5;</div><div class="line"><a name="l00214"></a><span class="lineno"> 214</span> </div><div class="line"><a name="l00215"></a><span class="lineno"> 215</span>  <span class="comment">// Find the two pixels in the perpendicular direction</span></div><div class="line"><a name="l00216"></a><span class="lineno"> 216</span>  short2 x_p = neighbours_coords[q_an].s02;</div><div class="line"><a name="l00217"></a><span class="lineno"> 217</span>  short2 y_p = neighbours_coords[q_an].s13;</div><div class="line"><a name="l00218"></a><span class="lineno"> 218</span>  DATA_TYPE_IN g1 = *((global DATA_TYPE_IN *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&grad, x_p.x, y_p.x));</div><div class="line"><a name="l00219"></a><span class="lineno"> 219</span>  DATA_TYPE_IN g2 = *((global DATA_TYPE_IN *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&grad, x_p.y, y_p.y));</div><div class="line"><a name="l00220"></a><span class="lineno"> 220</span> </div><div class="line"><a name="l00221"></a><span class="lineno"> 221</span>  <span class="keywordflow">if</span>((gradient > g1) && (gradient > g2))</div><div class="line"><a name="l00222"></a><span class="lineno"> 222</span>  {</div><div class="line"><a name="l00223"></a><span class="lineno"> 223</span>  *((global <a class="code" href="convolution3x3_8cl.xhtml#ac06f3e24d3fffd3c465d8b2a6e7c985e">DATA_TYPE_OUT</a> *)non_max.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>) = gradient;</div><div class="line"><a name="l00224"></a><span class="lineno"> 224</span>  }</div><div class="line"><a name="l00225"></a><span class="lineno"> 225</span> }</div><div class="line"><a name="l00226"></a><span class="lineno"> 226</span> </div><div class="line"><a name="l00227"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#ac243bfa96aa2c28014159ff098bd2324"> 227</a></span> <span class="preprocessor">#define EDGE 255</span></div><div class="line"><a name="l00228"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#a242e5ec23ae26cd2dfa5eab5ae68a0f1"> 228</a></span> <span class="preprocessor">#define hysteresis_local_stack_L1 8 // The size of level 1 stack. This has to agree with the host side</span></div><div class="line"><a name="l00229"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#aa55093fb165fb76898efb3ba80f62bae"> 229</a></span> <span class="preprocessor">#define hysteresis_local_stack_L2 1
2 // The size of level 2 stack, adjust this can impact the match rate with VX implementation</span></div><div class="line"><a name="l00230"></a><span class="lineno"> 230</span> </div><div class="line"><a name="l00242"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650"> 242</a></span> <span class="preprocessor">#define check_pixel(early_test, x_pos, y_pos, x_cur, y_cur) \</span></div><div class="line"><a name="l00243"></a><span class="lineno"> 243</span> <span class="preprocessor"> { \</span></div><div class="line"><a name="l00244"></a><span class="lineno"> 244</span> <span class="preprocessor"> if(!early_test) \</span></div><div class="line"><a name="l00245"></a><span class="lineno"> 245</span> <span class="preprocessor"> { \</span></div><div class="line"><a name="l00246"></a><span class="lineno"> 246</span> <span class="preprocessor"> </span><span class="comment">/* Number of elements in the local stack 1, points to next available entry */</span><span class="preprocessor"> \</span></div><div class="line"><a name="l00247"></a><span class="lineno"> 247</span> <span class="preprocessor"> c = *((__global char *)offset(&l1_stack_counter, x_cur, y_cur)); \</span></div><div class="line"><a name="l00248"></a><span class="lineno"> 248</span> <span class="preprocessor"> \</span></div><div class="line"><a name="l00249"></a><span class="lineno"> 249</span> <span class="preprocessor"> if(c > (hysteresis_local_stack_L1 - 1)) </span><span class="comment">/* Stack level 1 is full */</span><span class="preprocessor"> \</span></div><div class="line"><a name="l00250"></a><span class="lineno"> 250</span> <span class="preprocessor"> goto pop_stack; \</span></div><div class="line"><a name="l00251"></a><span class="lineno"> 251</span> <span class="preprocessor"> \</span></div><div class="line"><a name="l00252"></a><span class="lineno"> 252</span> <span class="preprocessor"> </span><span class="comment">/* The pixel that has already been recorded is ignored */</span><span class="preprocessor"> \</span></div><div class="line"><a name="l00253"></a><span class="lineno"> 253</span> <span class="preprocessor"> if(!atomic_or((__global uint *)offset(&recorded, x_pos, y_pos), 1)) \</span></div><div class="line"><a name="l00254"></a><span class="lineno"> 254</span> <span class="preprocessor"> { \</span></div><div class="line"><a name="l00255"></a><span class="lineno"> 255</span> <span class="preprocessor"> l1_ptr[c] = (short2)(x_pos, y_pos); \</span></div><div class="line"><a name="l00256"></a><span class="lineno"> 256</span> <span class="preprocessor"> *((__global char *)offset(&l1_stack_counter, x_cur, y_cur)) += 1; \</span></div><div class="line"><a name="l00257"></a><span class="lineno"> 257</span> <span class="preprocessor"> } \</span></div><div class="line"><a name="l00258"></a><span class="lineno"> 258</span> <span class="preprocessor"> } \</span></div><div class="line"><a name="l00259"></a><span class="lineno"> 259</span> <span class="preprocessor"> }</span></div><div class="line"><a name="l00260"></a><span class="lineno"> 260</span> </div><div class="line"><a name="l00306"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#acd62ae1c9f3d7a1c7e49499d308d1904"> 306</a></span> kernel <span class="keywordtype">void</span> <a class="code" href="canny_8cl.xhtml#acd62ae1c9f3d7a1c7e49499d308d1904">hysteresis</a>(</div><div class="line"><a name="l00307"></a><span class="lineno"> 307</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(src),</div><div class="line"><a name="l00308"></a><span class="lineno"> 308</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(out),</div><div class="line"><a name="l00309"></a><span class="lineno"> 309</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(visited),</div><div class="line"><a name="l00310"></a><span class="lineno"> 310</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(recorded),</div><div class="line"><a name="l00311"></a><span class="lineno"> 311</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(l1_stack),</div><div class="line"><a name="l00312"></a><span class="lineno"> 312</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(l1_stack_counter),</div><div class="line"><a name="l00313"></a><span class="lineno"> 313</span>  uint low_thr,</div><div class="line"><a name="l00314"></a><span class="lineno"> 314</span>  uint up_thr,</div><div class="line"><a name="l00315"></a><span class="lineno"> 315</span>  <span class="keywordtype">int</span> width,</div><div class="line"><a name="l00316"></a><span class="lineno"> 316</span>  <span class="keywordtype">int</span> height)</div><div class="line"><a name="l00317"></a><span class="lineno"> 317</span> {</div><div class="line"><a name="l00318"></a><span class="lineno"> 318</span>  <span class="comment">// Create images</span></div><div class="line"><a name="l00319"></a><span class="lineno"> 319</span>  <a class="code" href="struct_image.xhtml">Image</a> src = <a class="code" href="helpers_8h.xhtml#a4334a4a76f8e9628c0fb9e1acf616e2a">CONVERT_TO_IMAGE_STRUCT_NO_STEP</a>(src);</div><div class="line"><a name="l00320"></a><span class="lineno"> 320</span>  <a class="code" href="struct_image.xhtml">Image</a> out = <a class="code" href="helpers_8h.xhtml#a4334a4a76f8e9628c0fb9e1acf616e2a">CONVERT_TO_IMAGE_STRUCT_NO_STEP</a>(out);</div><div class="line"><a name="l00321"></a><span class="lineno"> 321</span>  <a class="code" href="struct_image.xhtml">Image</a> visited = <a class="code" href="helpers_8h.xhtml#a4334a4a76f8e9628c0fb9e1acf616e2a">CONVERT_TO_IMAGE_STRUCT_NO_STEP</a>(visited);</div><div class="line"><a name="l00322"></a><span class="lineno"> 322</span>  <a class="code" href="struct_image.xhtml">Image</a> recorded = <a class="code" href="helpers_8h.xhtml#a4334a4a76f8e9628c0fb9e1acf616e2a">CONVERT_TO_IMAGE_STRUCT_NO_STEP</a>(recorded);</div><div class="line"><a name="l00323"></a><span class="lineno"> 323</span>  <a class="code" href="struct_image.xhtml">Image</a> l1_stack = <a class="code" href="helpers_8h.xhtml#a4334a4a76f8e9628c0fb9e1acf616e2a">CONVERT_TO_IMAGE_STRUCT_NO_STEP</a>(l1_stack);</div><div class="line"><a name="l00324"></a><span class="lineno"> 324</span>  <a class="code" href="struct_image.xhtml">Image</a> l1_stack_counter = <a class="code" href="helpers_8h.xhtml#a4334a4a76f8e9628c0fb9e1acf616e2a">CONVERT_TO_IMAGE_STRUCT_NO_STEP</a>(l1_stack_counter);</div><div class="line"><a name="l00325"></a><span class="lineno"> 325</span> </div><div class="line"><a name="l00326"></a><span class="lineno"> 326</span>  <span class="comment">// Index</span></div><div class="line"><a name="l00327"></a><span class="lineno"> 327</span>  <span class="keywordtype">int</span> x = get_global_id(0);</div><div class="line"><a name="l00328"></a><span class="lineno"> 328</span>  <span class="keywordtype">int</span> y = get_global_id(1);</div><div class="line"><a name="l00329"></a><span class="lineno"> 329</span> </div><div class="line"><a name="l00330"></a><span class="lineno"> 330</span>  <span class="comment">// Load value</span></div><div class="line"><a name="l00331"></a><span class="lineno"> 331</span>  DATA_TYPE_IN val = *((__global DATA_TYPE_IN *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&src, x, y));</div><div class="line"><a name="l00332"></a><span class="lineno"> 332</span> </div><div class="line"><a name="l00333"></a><span class="lineno"> 333</span>  <span class="comment">// If less than upper threshold set to NO_EDGE and return</span></div><div class="line"><a name="l00334"></a><span class="lineno"> 334</span>  <span class="keywordflow">if</span>(val <= up_thr)</div><div class="line"><a name="l00335"></a><span class="lineno"> 335</span>  {</div><div class="line"><a name="l00336"></a><span class="lineno"> 336</span>  *<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&out, x, y) = 0;</div><div class="line"><a name="l00337"></a><span class="lineno"> 337</span>  <span class="keywordflow">return</span>;</div><div class="line"><a name="l00338"></a><span class="lineno"> 338</span>  }</div><div class="line"><a name="l00339"></a><span class="lineno"> 339</span> </div><div class="line"><a name="l00340"></a><span class="lineno"> 340</span>  <span class="comment">// Init local stack 2</span></div><div class="line"><a name="l00341"></a><span class="lineno"> 341</span>  short2 stack_L2[<a class="code" href="canny_8cl.xhtml#aa55093fb165fb76898efb3ba80f62bae">hysteresis_local_stack_L2</a>] = { 0 };</div><div class="line"><a name="l00342"></a><span class="lineno"> 342</span>  <span class="keywordtype">int</span> L2_counter = 0;</div><div class="line"><a name="l00343"></a><span class="lineno"> 343</span> </div><div class="line"><a name="l00344"></a><span class="lineno"> 344</span>  <span class="comment">// Perform recursive hysteresis</span></div><div class="line"><a name="l00345"></a><span class="lineno"> 345</span>  <span class="keywordflow">while</span>(<span class="keyword">true</span>)</div><div class="line"><a name="l00346"></a><span class="lineno"> 346</span>  {</div><div class="line"><a name="l00347"></a><span class="lineno"> 347</span>  <span class="comment">// Get L1 stack pointer</span></div><div class="line"><a name="l00348"></a><span class="lineno"> 348</span>  __global short2 *l1_ptr = (__global short2 *)(l1_stack.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a> + y * l1_stack.<a class="code" href="struct_image.xhtml#a4f0b90c9ecd6e57ceb3f37332fefe8f1">stride_y</a> + x * <a class="code" href="canny_8cl.xhtml#a242e5ec23ae26cd2dfa5eab5ae68a0f1">hysteresis_local_stack_L1</a> * l1_stack.<a class="code" href="struct_image.xhtml#ae01febbfd0689ef709f3ff6fdd2abc7e">stride_x</a>);</div><div class="line"><a name="l00349"></a><span class="lineno"> 349</span> </div><div class="line"><a name="l00350"></a><span class="lineno"> 350</span>  <span class="comment">// If the pixel has already been visited, proceed with the items in the stack instead</span></div><div class="line"><a name="l00351"></a><span class="lineno"> 351</span>  <span class="keywordflow">if</span>(atomic_or((__global uint *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&visited, x, y), 1) != 0)</div><div class="line"><a name="l00352"></a><span class="lineno"> 352</span>  {</div><div class="line"><a name="l00353"></a><span class="lineno"> 353</span>  <span class="keywordflow">goto</span> pop_stack;</div><div class="line"><a name="l00354"></a><span class="lineno"> 354</span>  }</div><div class="line"><a name="l00355"></a><span class="lineno"> 355</span> </div><div class="line"><a name="l00356"></a><span class="lineno"> 356</span>  <span class="comment">// Set strong edge</span></div><div class="line"><a name="l00357"></a><span class="lineno"> 357</span>  *<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&out, x, y) = <a class="code" href="canny_8cl.xhtml#ac243bfa96aa2c28014159ff098bd2324">EDGE</a>;</div><div class="line"><a name="l00358"></a><span class="lineno"> 358</span> </div><div class="line"><a name="l00359"></a><span class="lineno"> 359</span>  <span class="comment">// If it is the top of stack l2, we don't need check the surrounding pixels</span></div><div class="line"><a name="l00360"></a><span class="lineno"> 360</span>  <span class="keywordflow">if</span>(L2_counter > (<a class="code" href="canny_8cl.xhtml#aa55093fb165fb76898efb3ba80f62bae">hysteresis_local_stack_L2</a> - 1))</div><div class="line"><a name="l00361"></a><span class="lineno"> 361</span>  {</div><div class="line"><a name="l00362"></a><span class="lineno"> 362</span>  <span class="keywordflow">goto</span> pop_stack2;</div><div class="line"><a name="l00363"></a><span class="lineno"> 363</span>  }</div><div class="line"><a name="l00364"></a><span class="lineno"> 364</span> </div><div class="line"><a name="l00365"></a><span class="lineno"> 365</span>  <span class="comment">// Points to the start of the local stack;</span></div><div class="line"><a name="l00366"></a><span class="lineno"> 366</span>  <span class="keywordtype">char</span> c;</div><div class="line"><a name="l00367"></a><span class="lineno"> 367</span> </div><div class="line"><a name="l00368"></a><span class="lineno"> 368</span>  <a class="code" href="helpers_8h.xhtml#a36f754c05b6fddf6df0d8d0a74f8159f">VEC_DATA_TYPE</a>(DATA_TYPE_IN, 4)</div><div class="line"><a name="l00369"></a><span class="lineno"> 369</span>  x_tmp;</div><div class="line"><a name="l00370"></a><span class="lineno"> 370</span>  uint4 v_tmp;</div><div class="line"><a name="l00371"></a><span class="lineno"> 371</span> </div><div class="line"><a name="l00372"></a><span class="lineno"> 372</span>  <span class="comment">// Get direction pixel indices</span></div><div class="line"><a name="l00373"></a><span class="lineno"> 373</span>  <span class="keywordtype">int</span> N = max(y - 1, 0), S = min(y + 1, height - 2), W = max(x - 1, 0), E = min(x + 1, width - 2);</div><div class="line"><a name="l00374"></a><span class="lineno"> 374</span> </div><div class="line"><a name="l00375"></a><span class="lineno"> 375</span>  <span class="comment">// Check 8 pixels around for week edges where low_thr < val <= up_thr</span></div><div class="line"><a name="l00376"></a><span class="lineno"> 376</span>  x_tmp = vload4(0, (__global DATA_TYPE_IN *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&src, W, N));</div><div class="line"><a name="l00377"></a><span class="lineno"> 377</span>  v_tmp = vload4(0, (__global uint *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&visited, W, N));</div><div class="line"><a name="l00378"></a><span class="lineno"> 378</span>  <a class="code" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650">check_pixel</a>(((x_tmp.s0 <= low_thr) || v_tmp.s0 || (x_tmp.s0 > up_thr)), W, N, x, y); <span class="comment">// NW</span></div><div class="line"><a name="l00379"></a><span class="lineno"> 379</span>  <a class="code" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650">check_pixel</a>(((x_tmp.s1 <= low_thr) || v_tmp.s1 || (x_tmp.s1 > up_thr)), x, N, x, y); <span class="comment">// N</span></div><div class="line"><a name="l00380"></a><span class="lineno"> 380</span>  <a class="code" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650">check_pixel</a>(((x_tmp.s2 <= low_thr) || v_tmp.s2 || (x_tmp.s2 > up_thr)), E, N, x, y); <span class="comment">// NE</span></div><div class="line"><a name="l00381"></a><span class="lineno"> 381</span> </div><div class="line"><a name="l00382"></a><span class="lineno"> 382</span>  x_tmp = vload4(0, (__global DATA_TYPE_IN *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&src, W, y));</div><div class="line"><a name="l00383"></a><span class="lineno"> 383</span>  v_tmp = vload4(0, (__global uint *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&visited, W, y));</div><div class="line"><a name="l00384"></a><span class="lineno"> 384</span>  <a class="code" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650">check_pixel</a>(((x_tmp.s0 <= low_thr) || v_tmp.s0 || (x_tmp.s0 > up_thr)), W, y, x, y); <span class="comment">// W</span></div><div class="line"><a name="l00385"></a><span class="lineno"> 385</span>  <a class="code" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650">check_pixel</a>(((x_tmp.s2 <= low_thr) || v_tmp.s2 || (x_tmp.s2 > up_thr)), E, y, x, y); <span class="comment">// E</span></div><div class="line"><a name="l00386"></a><span class="lineno"> 386</span> </div><div class="line"><a name="l00387"></a><span class="lineno"> 387</span>  x_tmp = vload4(0, (__global DATA_TYPE_IN *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&src, W, S));</div><div class="line"><a name="l00388"></a><span class="lineno"> 388</span>  v_tmp = vload4(0, (__global uint *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&visited, W, S));</div><div class="line"><a name="l00389"></a><span class="lineno"> 389</span>  <a class="code" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650">check_pixel</a>(((x_tmp.s0 <= low_thr) || v_tmp.s0 || (x_tmp.s0 > up_thr)), W, S, x, y); <span class="comment">// SW</span></div><div class="line"><a name="l00390"></a><span class="lineno"> 390</span>  <a class="code" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650">check_pixel</a>(((x_tmp.s1 <= low_thr) || v_tmp.s1 || (x_tmp.s1 > up_thr)), x, S, x, y); <span class="comment">// S</span></div><div class="line"><a name="l00391"></a><span class="lineno"> 391</span>  <a class="code" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650">check_pixel</a>(((x_tmp.s2 <= low_thr) || v_tmp.s2 || (x_tmp.s2 > up_thr)), E, S, x, y); <span class="comment">// SE</span></div><div class="line"><a name="l00392"></a><span class="lineno"> 392</span> </div><div class="line"><a name="l00393"></a><span class="lineno"> 393</span> <span class="preprocessor">#undef check_pixel</span></div><div class="line"><a name="l00394"></a><span class="lineno"> 394</span> </div><div class="line"><a name="l00395"></a><span class="lineno"> 395</span> pop_stack:</div><div class="line"><a name="l00396"></a><span class="lineno"> 396</span>  c = *((__global <span class="keywordtype">char</span> *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&l1_stack_counter, x, y));</div><div class="line"><a name="l00397"></a><span class="lineno"> 397</span> </div><div class="line"><a name="l00398"></a><span class="lineno"> 398</span>  <span class="keywordflow">if</span>(c >= 1)</div><div class="line"><a name="l00399"></a><span class="lineno"> 399</span>  {</div><div class="line"><a name="l00400"></a><span class="lineno"> 400</span>  *((__global <span class="keywordtype">char</span> *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&l1_stack_counter, x, y)) -= 1;</div><div class="line"><a name="l00401"></a><span class="lineno"> 401</span>  int2 l_c = convert_int2(l1_ptr[c - 1]);</div><div class="line"><a name="l00402"></a><span class="lineno"> 402</span> </div><div class="line"><a name="l00403"></a><span class="lineno"> 403</span>  <span class="comment">// Push the current position into level 2 stack</span></div><div class="line"><a name="l00404"></a><span class="lineno"> 404</span>  stack_L2[L2_counter].x = x;</div><div class="line"><a name="l00405"></a><span class="lineno"> 405</span>  stack_L2[L2_counter].y = y;</div><div class="line"><a name="l00406"></a><span class="lineno"> 406</span> </div><div class="line"><a name="l00407"></a><span class="lineno"> 407</span>  x = l_c.x;</div><div class="line"><a name="l00408"></a><span class="lineno"> 408</span>  y = l_c.y;</div><div class="line"><a name="l00409"></a><span class="lineno"> 409</span> </div><div class="line"><a name="l00410"></a><span class="lineno"> 410</span>  L2_counter++;</div><div class="line"><a name="l00411"></a><span class="lineno"> 411</span> </div><div class="line"><a name="l00412"></a><span class="lineno"> 412</span>  <span class="keywordflow">continue</span>;</div><div class="line"><a name="l00413"></a><span class="lineno"> 413</span>  }</div><div class="line"><a name="l00414"></a><span class="lineno"> 414</span> </div><div class="line"><a name="l00415"></a><span class="lineno"> 415</span>  <span class="keywordflow">if</span>(L2_counter > 0)</div><div class="line"><a name="l00416"></a><span class="lineno"> 416</span>  {</div><div class="line"><a name="l00417"></a><span class="lineno"> 417</span>  <span class="keywordflow">goto</span> pop_stack2;</div><div class="line"><a name="l00418"></a><span class="lineno"> 418</span>  }</div><div class="line"><a name="l00419"></a><span class="lineno"> 419</span>  <span class="keywordflow">else</span></div><div class="line"><a name="l00420"></a><span class="lineno"> 420</span>  {</div><div class="line"><a name="l00421"></a><span class="lineno"> 421</span>  <span class="keywordflow">return</span>;</div><div class="line"><a name="l00422"></a><span class="lineno"> 422</span>  }</div><div class="line"><a name="l00423"></a><span class="lineno"> 423</span> </div><div class="line"><a name="l00424"></a><span class="lineno"> 424</span> pop_stack2:</div><div class="line"><a name="l00425"></a><span class="lineno"> 425</span>  L2_counter--;</div><div class="line"><a name="l00426"></a><span class="lineno"> 426</span>  x = stack_L2[L2_counter].x;</div><div class="line"><a name="l00427"></a><span class="lineno"> 427</span>  y = stack_L2[L2_counter].y;</div><div class="line"><a name="l00428"></a><span class="lineno"> 428</span>  };</div><div class="line"><a name="l00429"></a><span class="lineno"> 429</span> }</div><div class="ttc" id="canny_8cl_xhtml_a242e5ec23ae26cd2dfa5eab5ae68a0f1"><div class="ttname"><a href="canny_8cl.xhtml#a242e5ec23ae26cd2dfa5eab5ae68a0f1">hysteresis_local_stack_L1</a></div><div class="ttdeci">#define hysteresis_local_stack_L1</div><div class="ttdef"><b>Definition:</b> <a href="canny_8cl_source.xhtml#l00228">canny.cl:228</a></div></div>
+<a href="canny_8cl.xhtml">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span> <span class="comment">/*</span></div><div class="line"><a name="l00002"></a><span class="lineno"> 2</span> <span class="comment"> * Copyright (c) 2017 ARM Limited.</span></div><div class="line"><a name="l00003"></a><span class="lineno"> 3</span> <span class="comment"> *</span></div><div class="line"><a name="l00004"></a><span class="lineno"> 4</span> <span class="comment"> * SPDX-License-Identifier: MIT</span></div><div class="line"><a name="l00005"></a><span class="lineno"> 5</span> <span class="comment"> *</span></div><div class="line"><a name="l00006"></a><span class="lineno"> 6</span> <span class="comment"> * Permission is hereby granted, free of charge, to any person obtaining a copy</span></div><div class="line"><a name="l00007"></a><span class="lineno"> 7</span> <span class="comment"> * of this software and associated documentation files (the "Software"), to</span></div><div class="line"><a name="l00008"></a><span class="lineno"> 8</span> <span class="comment"> * deal in the Software without restriction, including without limitation the</span></div><div class="line"><a name="l00009"></a><span class="lineno"> 9</span> <span class="comment"> * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or</span></div><div class="line"><a name="l00010"></a><span class="lineno"> 10</span> <span class="comment"> * sell copies of the Software, and to permit persons to whom the Software is</span></div><div class="line"><a name="l00011"></a><span class="lineno"> 11</span> <span class="comment"> * furnished to do so, subject to the following conditions:</span></div><div class="line"><a name="l00012"></a><span class="lineno"> 12</span> <span class="comment"> *</span></div><div class="line"><a name="l00013"></a><span class="lineno"> 13</span> <span class="comment"> * The above copyright notice and this permission notice shall be included in all</span></div><div class="line"><a name="l00014"></a><span class="lineno"> 14</span> <span class="comment"> * copies or substantial portions of the Software.</span></div><div class="line"><a name="l00015"></a><span class="lineno"> 15</span> <span class="comment"> *</span></div><div class="line"><a name="l00016"></a><span class="lineno"> 16</span> <span class="comment"> * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR</span></div><div class="line"><a name="l00017"></a><span class="lineno"> 17</span> <span class="comment"> * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,</span></div><div class="line"><a name="l00018"></a><span class="lineno"> 18</span> <span class="comment"> * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE</span></div><div class="line"><a name="l00019"></a><span class="lineno"> 19</span> <span class="comment"> * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER</span></div><div class="line"><a name="l00020"></a><span class="lineno"> 20</span> <span class="comment"> * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,</span></div><div class="line"><a name="l00021"></a><span class="lineno"> 21</span> <span class="comment"> * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE</span></div><div class="line"><a name="l00022"></a><span class="lineno"> 22</span> <span class="comment"> * SOFTWARE.</span></div><div class="line"><a name="l00023"></a><span class="lineno"> 23</span> <span class="comment"> */</span></div><div class="line"><a name="l00024"></a><span class="lineno"> 24</span> <span class="preprocessor">#include "<a class="code" href="helpers_8h.xhtml">helpers.h</a>"</span></div><div class="line"><a name="l00025"></a><span class="lineno"> 25</span> </div><div class="line"><a name="l00057"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#a92f95668118a1bc6ef0eed965dfd570f"> 57</a></span> __kernel <span class="keywordtype">void</span> <a class="code" href="canny_8cl.xhtml#a92f95668118a1bc6ef0eed965dfd570f">combine_gradients_L1</a>(</div><div class="line"><a name="l00058"></a><span class="lineno"> 58</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(src1),</div><div class="line"><a name="l00059"></a><span class="lineno"> 59</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(src2),</div><div class="line"><a name="l00060"></a><span class="lineno"> 60</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(grad),</div><div class="line"><a name="l00061"></a><span class="lineno"> 61</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(angle))</div><div class="line"><a name="l00062"></a><span class="lineno"> 62</span> {</div><div class="line"><a name="l00063"></a><span class="lineno"> 63</span>  <span class="comment">// Construct images</span></div><div class="line"><a name="l00064"></a><span class="lineno"> 64</span>  <a class="code" href="struct_image.xhtml">Image</a> src1 = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(src1);</div><div class="line"><a name="l00065"></a><span class="lineno"> 65</span>  <a class="code" href="struct_image.xhtml">Image</a> src2 = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(src2);</div><div class="line"><a name="l00066"></a><span class="lineno"> 66</span>  <a class="code" href="struct_image.xhtml">Image</a> grad = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(grad);</div><div class="line"><a name="l00067"></a><span class="lineno"> 67</span>  <a class="code" href="struct_image.xhtml">Image</a> angle = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(angle);</div><div class="line"><a name="l00068"></a><span class="lineno"> 68</span> </div><div class="line"><a name="l00069"></a><span class="lineno"> 69</span>  <span class="comment">// Load sobel horizontal and vertical values</span></div><div class="line"><a name="l00070"></a><span class="lineno"> 70</span>  <a class="code" href="helpers_8h.xhtml#a36f754c05b6fddf6df0d8d0a74f8159f">VEC_DATA_TYPE</a>(DATA_TYPE_IN, 4)</div><div class="line"><a name="l00071"></a><span class="lineno"> 71</span>  h = vload4(0, (__global DATA_TYPE_IN *)src1.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>);</div><div class="line"><a name="l00072"></a><span class="lineno"> 72</span>  <a class="code" href="helpers_8h.xhtml#a36f754c05b6fddf6df0d8d0a74f8159f">VEC_DATA_TYPE</a>(DATA_TYPE_IN, 4)</div><div class="line"><a name="l00073"></a><span class="lineno"> 73</span>  v = vload4(0, (__global DATA_TYPE_IN *)src2.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>);</div><div class="line"><a name="l00074"></a><span class="lineno"> 74</span> </div><div class="line"><a name="l00075"></a><span class="lineno"> 75</span>  <span class="comment">/* Calculate the gradient, using level 1 normalisation method */</span></div><div class="line"><a name="l00076"></a><span class="lineno"> 76</span>  <a class="code" href="helpers_8h.xhtml#a36f754c05b6fddf6df0d8d0a74f8159f">VEC_DATA_TYPE</a>(<a class="code" href="convolution3x3_8cl.xhtml#ac06f3e24d3fffd3c465d8b2a6e7c985e">DATA_TYPE_OUT</a>, 4)</div><div class="line"><a name="l00077"></a><span class="lineno"> 77</span>  m = <a class="code" href="helpers_8h.xhtml#a23fb01b6f3453cc0e48a026fd44f6acd">CONVERT_SAT</a>((abs(h) + abs(v)), <a class="code" href="helpers_8h.xhtml#a36f754c05b6fddf6df0d8d0a74f8159f">VEC_DATA_TYPE</a>(<a class="code" href="convolution3x3_8cl.xhtml#ac06f3e24d3fffd3c465d8b2a6e7c985e">DATA_TYPE_OUT</a>, 4));</div><div class="line"><a name="l00078"></a><span class="lineno"> 78</span> </div><div class="line"><a name="l00079"></a><span class="lineno"> 79</span>  <span class="comment">/* Calculate the angle */</span></div><div class="line"><a name="l00080"></a><span class="lineno"> 80</span>  float4 p = atan2pi(convert_float4(v), convert_float4(h));</div><div class="line"><a name="l00081"></a><span class="lineno"> 81</span> </div><div class="line"><a name="l00082"></a><span class="lineno"> 82</span>  <span class="comment">/* Remap angle to range [0, 256) */</span></div><div class="line"><a name="l00083"></a><span class="lineno"> 83</span>  p = select(p, p + 2, p < 0.0f) * 128.0f;</div><div class="line"><a name="l00084"></a><span class="lineno"> 84</span> </div><div class="line"><a name="l00085"></a><span class="lineno"> 85</span>  <span class="comment">/* Store results */</span></div><div class="line"><a name="l00086"></a><span class="lineno"> 86</span>  vstore4(m, 0, (__global <a class="code" href="convolution3x3_8cl.xhtml#ac06f3e24d3fffd3c465d8b2a6e7c985e">DATA_TYPE_OUT</a> *)grad.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>);</div><div class="line"><a name="l00087"></a><span class="lineno"> 87</span>  vstore4(convert_uchar4_sat_rte(p), 0, angle.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>);</div><div class="line"><a name="l00088"></a><span class="lineno"> 88</span> }</div><div class="line"><a name="l00089"></a><span class="lineno"> 89</span> </div><div class="line"><a name="l00121"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#a7046357526e2f95a34e3ffa217752d9f"> 121</a></span> __kernel <span class="keywordtype">void</span> <a class="code" href="canny_8cl.xhtml#a7046357526e2f95a34e3ffa217752d9f">combine_gradients_L2</a>(</div><div class="line"><a name="l00122"></a><span class="lineno"> 122</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(src1),</div><div class="line"><a name="l00123"></a><span class="lineno"> 123</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(src2),</div><div class="line"><a name="l00124"></a><span class="lineno"> 124</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(grad),</div><div class="line"><a name="l00125"></a><span class="lineno"> 125</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(angle))</div><div class="line"><a name="l00126"></a><span class="lineno"> 126</span> {</div><div class="line"><a name="l00127"></a><span class="lineno"> 127</span>  <span class="comment">// Construct images</span></div><div class="line"><a name="l00128"></a><span class="lineno"> 128</span>  <a class="code" href="struct_image.xhtml">Image</a> src1 = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(src1);</div><div class="line"><a name="l00129"></a><span class="lineno"> 129</span>  <a class="code" href="struct_image.xhtml">Image</a> src2 = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(src2);</div><div class="line"><a name="l00130"></a><span class="lineno"> 130</span>  <a class="code" href="struct_image.xhtml">Image</a> grad = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(grad);</div><div class="line"><a name="l00131"></a><span class="lineno"> 131</span>  <a class="code" href="struct_image.xhtml">Image</a> angle = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(angle);</div><div class="line"><a name="l00132"></a><span class="lineno"> 132</span> </div><div class="line"><a name="l00133"></a><span class="lineno"> 133</span>  <span class="comment">// Load sobel horizontal and vertical values</span></div><div class="line"><a name="l00134"></a><span class="lineno"> 134</span>  float4 h = convert_float4(vload4(0, (__global DATA_TYPE_IN *)src1.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>));</div><div class="line"><a name="l00135"></a><span class="lineno"> 135</span>  float4 v = convert_float4(vload4(0, (__global DATA_TYPE_IN *)src2.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>));</div><div class="line"><a name="l00136"></a><span class="lineno"> 136</span> </div><div class="line"><a name="l00137"></a><span class="lineno"> 137</span>  <span class="comment">/* Calculate the gradient, using level 2 normalisation method */</span></div><div class="line"><a name="l00138"></a><span class="lineno"> 138</span>  float4 m = sqrt(h * h + v * v);</div><div class="line"><a name="l00139"></a><span class="lineno"> 139</span> </div><div class="line"><a name="l00140"></a><span class="lineno"> 140</span>  <span class="comment">/* Calculate the angle */</span></div><div class="line"><a name="l00141"></a><span class="lineno"> 141</span>  float4 p = atan2pi(v, h);</div><div class="line"><a name="l00142"></a><span class="lineno"> 142</span> </div><div class="line"><a name="l00143"></a><span class="lineno"> 143</span>  <span class="comment">/* Remap angle to range [0, 256) */</span></div><div class="line"><a name="l00144"></a><span class="lineno"> 144</span>  p = select(p, p + 2, p < 0.0f) * 128.0f;</div><div class="line"><a name="l00145"></a><span class="lineno"> 145</span> </div><div class="line"><a name="l00146"></a><span class="lineno"> 146</span>  <span class="comment">/* Store results */</span></div><div class="line"><a name="l00147"></a><span class="lineno"> 147</span>  vstore4(<a class="code" href="helpers_8h.xhtml#a28b2b123792a5b11a32cb05a6d327437">CONVERT_SAT_ROUND</a>(m, <a class="code" href="helpers_8h.xhtml#a36f754c05b6fddf6df0d8d0a74f8159f">VEC_DATA_TYPE</a>(<a class="code" href="convolution3x3_8cl.xhtml#ac06f3e24d3fffd3c465d8b2a6e7c985e">DATA_TYPE_OUT</a>, 4), rte), 0, (__global <a class="code" href="convolution3x3_8cl.xhtml#ac06f3e24d3fffd3c465d8b2a6e7c985e">DATA_TYPE_OUT</a> *)grad.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>);</div><div class="line"><a name="l00148"></a><span class="lineno"> 148</span>  vstore4(convert_uchar4_sat_rte(p), 0, angle.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>);</div><div class="line"><a name="l00149"></a><span class="lineno"> 149</span> }</div><div class="line"><a name="l00150"></a><span class="lineno"> 150</span> </div><div class="line"><a name="l00153"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#a65e45b2f8637f10dd14a427f37c2cd4c"> 153</a></span> __constant short4 <a class="code" href="canny_8cl.xhtml#a65e45b2f8637f10dd14a427f37c2cd4c">neighbours_coords</a>[] =</div><div class="line"><a name="l00154"></a><span class="lineno"> 154</span> {</div><div class="line"><a name="l00155"></a><span class="lineno"> 155</span>  { -1, 0, 1, 0 }, <span class="comment">// 0</span></div><div class="line"><a name="l00156"></a><span class="lineno"> 156</span>  { -1, 1, 1, -1 }, <span class="comment">// 45</span></div><div class="line"><a name="l00157"></a><span class="lineno"> 157</span>  { 0, 1, 0, -1 }, <span class="comment">// 90</span></div><div class="line"><a name="l00158"></a><span class="lineno"> 158</span>  { 1, 1, -1, -1 }, <span class="comment">// 135</span></div><div class="line"><a name="l00159"></a><span class="lineno"> 159</span>  { 1, 0, -1, 0 }, <span class="comment">// 180</span></div><div class="line"><a name="l00160"></a><span class="lineno"> 160</span>  { 1, -1, -1, 1 }, <span class="comment">// 225</span></div><div class="line"><a name="l00161"></a><span class="lineno"> 161</span>  { 0, 1, 0, -1 }, <span class="comment">// 270</span></div><div class="line"><a name="l00162"></a><span class="lineno"> 162</span>  { -1, -1, 1, 1 }, <span class="comment">// 315</span></div><div class="line"><a name="l00163"></a><span class="lineno"> 163</span>  { -1, 0, 1, 0 }, <span class="comment">// 360</span></div><div class="line"><a name="l00164"></a><span class="lineno"> 164</span> };</div><div class="line"><a name="l00165"></a><span class="lineno"> 165</span> </div><div class="line"><a name="l00191"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#a8c233c75ee1010bcec8601d559f4be68"> 191</a></span> __kernel <span class="keywordtype">void</span> <a class="code" href="canny_8cl.xhtml#a8c233c75ee1010bcec8601d559f4be68">suppress_non_maximum</a>(</div><div class="line"><a name="l00192"></a><span class="lineno"> 192</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(grad),</div><div class="line"><a name="l00193"></a><span class="lineno"> 193</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(angle),</div><div class="line"><a name="l00194"></a><span class="lineno"> 194</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(non_max),</div><div class="line"><a name="l00195"></a><span class="lineno"> 195</span>  uint lower_thr)</div><div class="line"><a name="l00196"></a><span class="lineno"> 196</span> {</div><div class="line"><a name="l00197"></a><span class="lineno"> 197</span>  <span class="comment">// Construct images</span></div><div class="line"><a name="l00198"></a><span class="lineno"> 198</span>  <a class="code" href="struct_image.xhtml">Image</a> grad = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(grad);</div><div class="line"><a name="l00199"></a><span class="lineno"> 199</span>  <a class="code" href="struct_image.xhtml">Image</a> angle = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(angle);</div><div class="line"><a name="l00200"></a><span class="lineno"> 200</span>  <a class="code" href="struct_image.xhtml">Image</a> non_max = <a class="code" href="helpers_8h.xhtml#aebe814363556c244be043b13e7969197">CONVERT_TO_IMAGE_STRUCT</a>(non_max);</div><div class="line"><a name="l00201"></a><span class="lineno"> 201</span> </div><div class="line"><a name="l00202"></a><span class="lineno"> 202</span>  <span class="comment">// Get gradient and angle</span></div><div class="line"><a name="l00203"></a><span class="lineno"> 203</span>  DATA_TYPE_IN gradient = *((__global DATA_TYPE_IN *)grad.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>);</div><div class="line"><a name="l00204"></a><span class="lineno"> 204</span>  uchar an = convert_ushort(*angle.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>);</div><div class="line"><a name="l00205"></a><span class="lineno"> 205</span> </div><div class="line"><a name="l00206"></a><span class="lineno"> 206</span>  <span class="keywordflow">if</span>(gradient <= lower_thr)</div><div class="line"><a name="l00207"></a><span class="lineno"> 207</span>  {</div><div class="line"><a name="l00208"></a><span class="lineno"> 208</span>  <span class="keywordflow">return</span>;</div><div class="line"><a name="l00209"></a><span class="lineno"> 209</span>  }</div><div class="line"><a name="l00210"></a><span class="lineno"> 210</span> </div><div class="line"><a name="l00211"></a><span class="lineno"> 211</span>  <span class="comment">// Divide the whole round into 8 directions</span></div><div class="line"><a name="l00212"></a><span class="lineno"> 212</span>  uchar ang = 127 - an;</div><div class="line"><a name="l00213"></a><span class="lineno"> 213</span>  <a class="code" href="convolution3x3_8cl.xhtml#ac06f3e24d3fffd3c465d8b2a6e7c985e">DATA_TYPE_OUT</a> q_an = (ang + 16) >> 5;</div><div class="line"><a name="l00214"></a><span class="lineno"> 214</span> </div><div class="line"><a name="l00215"></a><span class="lineno"> 215</span>  <span class="comment">// Find the two pixels in the perpendicular direction</span></div><div class="line"><a name="l00216"></a><span class="lineno"> 216</span>  short2 x_p = neighbours_coords[q_an].s02;</div><div class="line"><a name="l00217"></a><span class="lineno"> 217</span>  short2 y_p = neighbours_coords[q_an].s13;</div><div class="line"><a name="l00218"></a><span class="lineno"> 218</span>  DATA_TYPE_IN g1 = *((global DATA_TYPE_IN *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&grad, x_p.x, y_p.x));</div><div class="line"><a name="l00219"></a><span class="lineno"> 219</span>  DATA_TYPE_IN g2 = *((global DATA_TYPE_IN *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&grad, x_p.y, y_p.y));</div><div class="line"><a name="l00220"></a><span class="lineno"> 220</span> </div><div class="line"><a name="l00221"></a><span class="lineno"> 221</span>  <span class="keywordflow">if</span>((gradient > g1) && (gradient > g2))</div><div class="line"><a name="l00222"></a><span class="lineno"> 222</span>  {</div><div class="line"><a name="l00223"></a><span class="lineno"> 223</span>  *((global <a class="code" href="convolution3x3_8cl.xhtml#ac06f3e24d3fffd3c465d8b2a6e7c985e">DATA_TYPE_OUT</a> *)non_max.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a>) = gradient;</div><div class="line"><a name="l00224"></a><span class="lineno"> 224</span>  }</div><div class="line"><a name="l00225"></a><span class="lineno"> 225</span> }</div><div class="line"><a name="l00226"></a><span class="lineno"> 226</span> </div><div class="line"><a name="l00227"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#ac243bfa96aa2c28014159ff098bd2324"> 227</a></span> <span class="preprocessor">#define EDGE 255</span></div><div class="line"><a name="l00228"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#a242e5ec23ae26cd2dfa5eab5ae68a0f1"> 228</a></span> <span class="preprocessor">#define hysteresis_local_stack_L1 8 // The size of level 1 stack. This has to agree with the host side</span></div><div class="line"><a name="l00229"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#aa55093fb165fb76898efb3ba80f62bae"> 229</a></span> <span class="preprocessor">#define hysteresis_local_stack_L2 1
6 // The size of level 2 stack, adjust this can impact the match rate with VX implementation</span></div><div class="line"><a name="l00230"></a><span class="lineno"> 230</span> </div><div class="line"><a name="l00242"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650"> 242</a></span> <span class="preprocessor">#define check_pixel(early_test, x_pos, y_pos, x_cur, y_cur) \</span></div><div class="line"><a name="l00243"></a><span class="lineno"> 243</span> <span class="preprocessor"> { \</span></div><div class="line"><a name="l00244"></a><span class="lineno"> 244</span> <span class="preprocessor"> if(!early_test) \</span></div><div class="line"><a name="l00245"></a><span class="lineno"> 245</span> <span class="preprocessor"> { \</span></div><div class="line"><a name="l00246"></a><span class="lineno"> 246</span> <span class="preprocessor"> </span><span class="comment">/* Number of elements in the local stack 1, points to next available entry */</span><span class="preprocessor"> \</span></div><div class="line"><a name="l00247"></a><span class="lineno"> 247</span> <span class="preprocessor"> c = *((__global char *)offset(&l1_stack_counter, x_cur, y_cur)); \</span></div><div class="line"><a name="l00248"></a><span class="lineno"> 248</span> <span class="preprocessor"> \</span></div><div class="line"><a name="l00249"></a><span class="lineno"> 249</span> <span class="preprocessor"> if(c > (hysteresis_local_stack_L1 - 1)) </span><span class="comment">/* Stack level 1 is full */</span><span class="preprocessor"> \</span></div><div class="line"><a name="l00250"></a><span class="lineno"> 250</span> <span class="preprocessor"> goto pop_stack; \</span></div><div class="line"><a name="l00251"></a><span class="lineno"> 251</span> <span class="preprocessor"> \</span></div><div class="line"><a name="l00252"></a><span class="lineno"> 252</span> <span class="preprocessor"> </span><span class="comment">/* The pixel that has already been recorded is ignored */</span><span class="preprocessor"> \</span></div><div class="line"><a name="l00253"></a><span class="lineno"> 253</span> <span class="preprocessor"> if(!atomic_or((__global uint *)offset(&recorded, x_pos, y_pos), 1)) \</span></div><div class="line"><a name="l00254"></a><span class="lineno"> 254</span> <span class="preprocessor"> { \</span></div><div class="line"><a name="l00255"></a><span class="lineno"> 255</span> <span class="preprocessor"> l1_ptr[c] = (short2)(x_pos, y_pos); \</span></div><div class="line"><a name="l00256"></a><span class="lineno"> 256</span> <span class="preprocessor"> *((__global char *)offset(&l1_stack_counter, x_cur, y_cur)) += 1; \</span></div><div class="line"><a name="l00257"></a><span class="lineno"> 257</span> <span class="preprocessor"> } \</span></div><div class="line"><a name="l00258"></a><span class="lineno"> 258</span> <span class="preprocessor"> } \</span></div><div class="line"><a name="l00259"></a><span class="lineno"> 259</span> <span class="preprocessor"> }</span></div><div class="line"><a name="l00260"></a><span class="lineno"> 260</span> </div><div class="line"><a name="l00306"></a><span class="lineno"><a class="line" href="canny_8cl.xhtml#acd62ae1c9f3d7a1c7e49499d308d1904"> 306</a></span> kernel <span class="keywordtype">void</span> <a class="code" href="canny_8cl.xhtml#acd62ae1c9f3d7a1c7e49499d308d1904">hysteresis</a>(</div><div class="line"><a name="l00307"></a><span class="lineno"> 307</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(src),</div><div class="line"><a name="l00308"></a><span class="lineno"> 308</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(out),</div><div class="line"><a name="l00309"></a><span class="lineno"> 309</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(visited),</div><div class="line"><a name="l00310"></a><span class="lineno"> 310</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(recorded),</div><div class="line"><a name="l00311"></a><span class="lineno"> 311</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(l1_stack),</div><div class="line"><a name="l00312"></a><span class="lineno"> 312</span>  <a class="code" href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a>(l1_stack_counter),</div><div class="line"><a name="l00313"></a><span class="lineno"> 313</span>  uint low_thr,</div><div class="line"><a name="l00314"></a><span class="lineno"> 314</span>  uint up_thr,</div><div class="line"><a name="l00315"></a><span class="lineno"> 315</span>  <span class="keywordtype">int</span> width,</div><div class="line"><a name="l00316"></a><span class="lineno"> 316</span>  <span class="keywordtype">int</span> height)</div><div class="line"><a name="l00317"></a><span class="lineno"> 317</span> {</div><div class="line"><a name="l00318"></a><span class="lineno"> 318</span>  <span class="comment">// Create images</span></div><div class="line"><a name="l00319"></a><span class="lineno"> 319</span>  <a class="code" href="struct_image.xhtml">Image</a> src = <a class="code" href="helpers_8h.xhtml#a4334a4a76f8e9628c0fb9e1acf616e2a">CONVERT_TO_IMAGE_STRUCT_NO_STEP</a>(src);</div><div class="line"><a name="l00320"></a><span class="lineno"> 320</span>  <a class="code" href="struct_image.xhtml">Image</a> out = <a class="code" href="helpers_8h.xhtml#a4334a4a76f8e9628c0fb9e1acf616e2a">CONVERT_TO_IMAGE_STRUCT_NO_STEP</a>(out);</div><div class="line"><a name="l00321"></a><span class="lineno"> 321</span>  <a class="code" href="struct_image.xhtml">Image</a> visited = <a class="code" href="helpers_8h.xhtml#a4334a4a76f8e9628c0fb9e1acf616e2a">CONVERT_TO_IMAGE_STRUCT_NO_STEP</a>(visited);</div><div class="line"><a name="l00322"></a><span class="lineno"> 322</span>  <a class="code" href="struct_image.xhtml">Image</a> recorded = <a class="code" href="helpers_8h.xhtml#a4334a4a76f8e9628c0fb9e1acf616e2a">CONVERT_TO_IMAGE_STRUCT_NO_STEP</a>(recorded);</div><div class="line"><a name="l00323"></a><span class="lineno"> 323</span>  <a class="code" href="struct_image.xhtml">Image</a> l1_stack = <a class="code" href="helpers_8h.xhtml#a4334a4a76f8e9628c0fb9e1acf616e2a">CONVERT_TO_IMAGE_STRUCT_NO_STEP</a>(l1_stack);</div><div class="line"><a name="l00324"></a><span class="lineno"> 324</span>  <a class="code" href="struct_image.xhtml">Image</a> l1_stack_counter = <a class="code" href="helpers_8h.xhtml#a4334a4a76f8e9628c0fb9e1acf616e2a">CONVERT_TO_IMAGE_STRUCT_NO_STEP</a>(l1_stack_counter);</div><div class="line"><a name="l00325"></a><span class="lineno"> 325</span> </div><div class="line"><a name="l00326"></a><span class="lineno"> 326</span>  <span class="comment">// Index</span></div><div class="line"><a name="l00327"></a><span class="lineno"> 327</span>  <span class="keywordtype">int</span> x = get_global_id(0);</div><div class="line"><a name="l00328"></a><span class="lineno"> 328</span>  <span class="keywordtype">int</span> y = get_global_id(1);</div><div class="line"><a name="l00329"></a><span class="lineno"> 329</span> </div><div class="line"><a name="l00330"></a><span class="lineno"> 330</span>  <span class="comment">// Load value</span></div><div class="line"><a name="l00331"></a><span class="lineno"> 331</span>  DATA_TYPE_IN val = *((__global DATA_TYPE_IN *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&src, x, y));</div><div class="line"><a name="l00332"></a><span class="lineno"> 332</span> </div><div class="line"><a name="l00333"></a><span class="lineno"> 333</span>  <span class="comment">// If less than upper threshold set to NO_EDGE and return</span></div><div class="line"><a name="l00334"></a><span class="lineno"> 334</span>  <span class="keywordflow">if</span>(val <= up_thr)</div><div class="line"><a name="l00335"></a><span class="lineno"> 335</span>  {</div><div class="line"><a name="l00336"></a><span class="lineno"> 336</span>  *<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&out, x, y) = 0;</div><div class="line"><a name="l00337"></a><span class="lineno"> 337</span>  <span class="keywordflow">return</span>;</div><div class="line"><a name="l00338"></a><span class="lineno"> 338</span>  }</div><div class="line"><a name="l00339"></a><span class="lineno"> 339</span> </div><div class="line"><a name="l00340"></a><span class="lineno"> 340</span>  <span class="comment">// Init local stack 2</span></div><div class="line"><a name="l00341"></a><span class="lineno"> 341</span>  short2 stack_L2[<a class="code" href="canny_8cl.xhtml#aa55093fb165fb76898efb3ba80f62bae">hysteresis_local_stack_L2</a>] = { 0 };</div><div class="line"><a name="l00342"></a><span class="lineno"> 342</span>  <span class="keywordtype">int</span> L2_counter = 0;</div><div class="line"><a name="l00343"></a><span class="lineno"> 343</span> </div><div class="line"><a name="l00344"></a><span class="lineno"> 344</span>  <span class="comment">// Perform recursive hysteresis</span></div><div class="line"><a name="l00345"></a><span class="lineno"> 345</span>  <span class="keywordflow">while</span>(<span class="keyword">true</span>)</div><div class="line"><a name="l00346"></a><span class="lineno"> 346</span>  {</div><div class="line"><a name="l00347"></a><span class="lineno"> 347</span>  <span class="comment">// Get L1 stack pointer</span></div><div class="line"><a name="l00348"></a><span class="lineno"> 348</span>  __global short2 *l1_ptr = (__global short2 *)(l1_stack.<a class="code" href="struct_image.xhtml#acf52c23cbd7424606c10a606524e3e32">ptr</a> + y * l1_stack.<a class="code" href="struct_image.xhtml#a4f0b90c9ecd6e57ceb3f37332fefe8f1">stride_y</a> + x * <a class="code" href="canny_8cl.xhtml#a242e5ec23ae26cd2dfa5eab5ae68a0f1">hysteresis_local_stack_L1</a> * l1_stack.<a class="code" href="struct_image.xhtml#ae01febbfd0689ef709f3ff6fdd2abc7e">stride_x</a>);</div><div class="line"><a name="l00349"></a><span class="lineno"> 349</span> </div><div class="line"><a name="l00350"></a><span class="lineno"> 350</span>  <span class="comment">// If the pixel has already been visited, proceed with the items in the stack instead</span></div><div class="line"><a name="l00351"></a><span class="lineno"> 351</span>  <span class="keywordflow">if</span>(atomic_or((__global uint *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&visited, x, y), 1) != 0)</div><div class="line"><a name="l00352"></a><span class="lineno"> 352</span>  {</div><div class="line"><a name="l00353"></a><span class="lineno"> 353</span>  <span class="keywordflow">goto</span> pop_stack;</div><div class="line"><a name="l00354"></a><span class="lineno"> 354</span>  }</div><div class="line"><a name="l00355"></a><span class="lineno"> 355</span> </div><div class="line"><a name="l00356"></a><span class="lineno"> 356</span>  <span class="comment">// Set strong edge</span></div><div class="line"><a name="l00357"></a><span class="lineno"> 357</span>  *<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&out, x, y) = <a class="code" href="canny_8cl.xhtml#ac243bfa96aa2c28014159ff098bd2324">EDGE</a>;</div><div class="line"><a name="l00358"></a><span class="lineno"> 358</span> </div><div class="line"><a name="l00359"></a><span class="lineno"> 359</span>  <span class="comment">// If it is the top of stack l2, we don't need check the surrounding pixels</span></div><div class="line"><a name="l00360"></a><span class="lineno"> 360</span>  <span class="keywordflow">if</span>(L2_counter > (<a class="code" href="canny_8cl.xhtml#aa55093fb165fb76898efb3ba80f62bae">hysteresis_local_stack_L2</a> - 1))</div><div class="line"><a name="l00361"></a><span class="lineno"> 361</span>  {</div><div class="line"><a name="l00362"></a><span class="lineno"> 362</span>  <span class="keywordflow">goto</span> pop_stack2;</div><div class="line"><a name="l00363"></a><span class="lineno"> 363</span>  }</div><div class="line"><a name="l00364"></a><span class="lineno"> 364</span> </div><div class="line"><a name="l00365"></a><span class="lineno"> 365</span>  <span class="comment">// Points to the start of the local stack;</span></div><div class="line"><a name="l00366"></a><span class="lineno"> 366</span>  <span class="keywordtype">char</span> c;</div><div class="line"><a name="l00367"></a><span class="lineno"> 367</span> </div><div class="line"><a name="l00368"></a><span class="lineno"> 368</span>  <a class="code" href="helpers_8h.xhtml#a36f754c05b6fddf6df0d8d0a74f8159f">VEC_DATA_TYPE</a>(DATA_TYPE_IN, 4)</div><div class="line"><a name="l00369"></a><span class="lineno"> 369</span>  x_tmp;</div><div class="line"><a name="l00370"></a><span class="lineno"> 370</span>  uint4 v_tmp;</div><div class="line"><a name="l00371"></a><span class="lineno"> 371</span> </div><div class="line"><a name="l00372"></a><span class="lineno"> 372</span>  <span class="comment">// Get direction pixel indices</span></div><div class="line"><a name="l00373"></a><span class="lineno"> 373</span>  <span class="keywordtype">int</span> N = max(y - 1, 0), S = min(y + 1, height - 2), W = max(x - 1, 0), E = min(x + 1, width - 2);</div><div class="line"><a name="l00374"></a><span class="lineno"> 374</span> </div><div class="line"><a name="l00375"></a><span class="lineno"> 375</span>  <span class="comment">// Check 8 pixels around for week edges where low_thr < val <= up_thr</span></div><div class="line"><a name="l00376"></a><span class="lineno"> 376</span>  x_tmp = vload4(0, (__global DATA_TYPE_IN *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&src, W, N));</div><div class="line"><a name="l00377"></a><span class="lineno"> 377</span>  v_tmp = vload4(0, (__global uint *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&visited, W, N));</div><div class="line"><a name="l00378"></a><span class="lineno"> 378</span>  <a class="code" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650">check_pixel</a>(((x_tmp.s0 <= low_thr) || v_tmp.s0 || (x_tmp.s0 > up_thr)), W, N, x, y); <span class="comment">// NW</span></div><div class="line"><a name="l00379"></a><span class="lineno"> 379</span>  <a class="code" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650">check_pixel</a>(((x_tmp.s1 <= low_thr) || v_tmp.s1 || (x_tmp.s1 > up_thr)), x, N, x, y); <span class="comment">// N</span></div><div class="line"><a name="l00380"></a><span class="lineno"> 380</span>  <a class="code" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650">check_pixel</a>(((x_tmp.s2 <= low_thr) || v_tmp.s2 || (x_tmp.s2 > up_thr)), E, N, x, y); <span class="comment">// NE</span></div><div class="line"><a name="l00381"></a><span class="lineno"> 381</span> </div><div class="line"><a name="l00382"></a><span class="lineno"> 382</span>  x_tmp = vload4(0, (__global DATA_TYPE_IN *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&src, W, y));</div><div class="line"><a name="l00383"></a><span class="lineno"> 383</span>  v_tmp = vload4(0, (__global uint *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&visited, W, y));</div><div class="line"><a name="l00384"></a><span class="lineno"> 384</span>  <a class="code" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650">check_pixel</a>(((x_tmp.s0 <= low_thr) || v_tmp.s0 || (x_tmp.s0 > up_thr)), W, y, x, y); <span class="comment">// W</span></div><div class="line"><a name="l00385"></a><span class="lineno"> 385</span>  <a class="code" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650">check_pixel</a>(((x_tmp.s2 <= low_thr) || v_tmp.s2 || (x_tmp.s2 > up_thr)), E, y, x, y); <span class="comment">// E</span></div><div class="line"><a name="l00386"></a><span class="lineno"> 386</span> </div><div class="line"><a name="l00387"></a><span class="lineno"> 387</span>  x_tmp = vload4(0, (__global DATA_TYPE_IN *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&src, W, S));</div><div class="line"><a name="l00388"></a><span class="lineno"> 388</span>  v_tmp = vload4(0, (__global uint *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&visited, W, S));</div><div class="line"><a name="l00389"></a><span class="lineno"> 389</span>  <a class="code" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650">check_pixel</a>(((x_tmp.s0 <= low_thr) || v_tmp.s0 || (x_tmp.s0 > up_thr)), W, S, x, y); <span class="comment">// SW</span></div><div class="line"><a name="l00390"></a><span class="lineno"> 390</span>  <a class="code" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650">check_pixel</a>(((x_tmp.s1 <= low_thr) || v_tmp.s1 || (x_tmp.s1 > up_thr)), x, S, x, y); <span class="comment">// S</span></div><div class="line"><a name="l00391"></a><span class="lineno"> 391</span>  <a class="code" href="canny_8cl.xhtml#a64ee229d1bcee88c8017356d5d485650">check_pixel</a>(((x_tmp.s2 <= low_thr) || v_tmp.s2 || (x_tmp.s2 > up_thr)), E, S, x, y); <span class="comment">// SE</span></div><div class="line"><a name="l00392"></a><span class="lineno"> 392</span> </div><div class="line"><a name="l00393"></a><span class="lineno"> 393</span> <span class="preprocessor">#undef check_pixel</span></div><div class="line"><a name="l00394"></a><span class="lineno"> 394</span> </div><div class="line"><a name="l00395"></a><span class="lineno"> 395</span> pop_stack:</div><div class="line"><a name="l00396"></a><span class="lineno"> 396</span>  c = *((__global <span class="keywordtype">char</span> *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&l1_stack_counter, x, y));</div><div class="line"><a name="l00397"></a><span class="lineno"> 397</span> </div><div class="line"><a name="l00398"></a><span class="lineno"> 398</span>  <span class="keywordflow">if</span>(c >= 1)</div><div class="line"><a name="l00399"></a><span class="lineno"> 399</span>  {</div><div class="line"><a name="l00400"></a><span class="lineno"> 400</span>  *((__global <span class="keywordtype">char</span> *)<a class="code" href="helpers_8h.xhtml#a009469e4d9b8fce3b6d5e97d2077827d">offset</a>(&l1_stack_counter, x, y)) -= 1;</div><div class="line"><a name="l00401"></a><span class="lineno"> 401</span>  int2 l_c = convert_int2(l1_ptr[c - 1]);</div><div class="line"><a name="l00402"></a><span class="lineno"> 402</span> </div><div class="line"><a name="l00403"></a><span class="lineno"> 403</span>  <span class="comment">// Push the current position into level 2 stack</span></div><div class="line"><a name="l00404"></a><span class="lineno"> 404</span>  stack_L2[L2_counter].x = x;</div><div class="line"><a name="l00405"></a><span class="lineno"> 405</span>  stack_L2[L2_counter].y = y;</div><div class="line"><a name="l00406"></a><span class="lineno"> 406</span> </div><div class="line"><a name="l00407"></a><span class="lineno"> 407</span>  x = l_c.x;</div><div class="line"><a name="l00408"></a><span class="lineno"> 408</span>  y = l_c.y;</div><div class="line"><a name="l00409"></a><span class="lineno"> 409</span> </div><div class="line"><a name="l00410"></a><span class="lineno"> 410</span>  L2_counter++;</div><div class="line"><a name="l00411"></a><span class="lineno"> 411</span> </div><div class="line"><a name="l00412"></a><span class="lineno"> 412</span>  <span class="keywordflow">continue</span>;</div><div class="line"><a name="l00413"></a><span class="lineno"> 413</span>  }</div><div class="line"><a name="l00414"></a><span class="lineno"> 414</span> </div><div class="line"><a name="l00415"></a><span class="lineno"> 415</span>  <span class="keywordflow">if</span>(L2_counter > 0)</div><div class="line"><a name="l00416"></a><span class="lineno"> 416</span>  {</div><div class="line"><a name="l00417"></a><span class="lineno"> 417</span>  <span class="keywordflow">goto</span> pop_stack2;</div><div class="line"><a name="l00418"></a><span class="lineno"> 418</span>  }</div><div class="line"><a name="l00419"></a><span class="lineno"> 419</span>  <span class="keywordflow">else</span></div><div class="line"><a name="l00420"></a><span class="lineno"> 420</span>  {</div><div class="line"><a name="l00421"></a><span class="lineno"> 421</span>  <span class="keywordflow">return</span>;</div><div class="line"><a name="l00422"></a><span class="lineno"> 422</span>  }</div><div class="line"><a name="l00423"></a><span class="lineno"> 423</span> </div><div class="line"><a name="l00424"></a><span class="lineno"> 424</span> pop_stack2:</div><div class="line"><a name="l00425"></a><span class="lineno"> 425</span>  L2_counter--;</div><div class="line"><a name="l00426"></a><span class="lineno"> 426</span>  x = stack_L2[L2_counter].x;</div><div class="line"><a name="l00427"></a><span class="lineno"> 427</span>  y = stack_L2[L2_counter].y;</div><div class="line"><a name="l00428"></a><span class="lineno"> 428</span>  };</div><div class="line"><a name="l00429"></a><span class="lineno"> 429</span> }</div><div class="ttc" id="canny_8cl_xhtml_a242e5ec23ae26cd2dfa5eab5ae68a0f1"><div class="ttname"><a href="canny_8cl.xhtml#a242e5ec23ae26cd2dfa5eab5ae68a0f1">hysteresis_local_stack_L1</a></div><div class="ttdeci">#define hysteresis_local_stack_L1</div><div class="ttdef"><b>Definition:</b> <a href="canny_8cl_source.xhtml#l00228">canny.cl:228</a></div></div>
<div class="ttc" id="canny_8cl_xhtml_a8c233c75ee1010bcec8601d559f4be68"><div class="ttname"><a href="canny_8cl.xhtml#a8c233c75ee1010bcec8601d559f4be68">suppress_non_maximum</a></div><div class="ttdeci">__kernel void suppress_non_maximum(__global uchar *grad_ptr, uint grad_stride_x, uint grad_step_x, uint grad_stride_y, uint grad_step_y, uint grad_offset_first_element_in_bytes, __global uchar *angle_ptr, uint angle_stride_x, uint angle_step_x, uint angle_stride_y, uint angle_step_y, uint angle_offset_first_element_in_bytes, __global uchar *non_max_ptr, uint non_max_stride_x, uint non_max_step_x, uint non_max_stride_y, uint non_max_step_y, uint non_max_offset_first_element_in_bytes, uint lower_thr)</div><div class="ttdoc">Perform non maximum suppression. </div><div class="ttdef"><b>Definition:</b> <a href="canny_8cl_source.xhtml#l00191">canny.cl:191</a></div></div>
<div class="ttc" id="helpers_8h_xhtml_a4334a4a76f8e9628c0fb9e1acf616e2a"><div class="ttname"><a href="helpers_8h.xhtml#a4334a4a76f8e9628c0fb9e1acf616e2a">CONVERT_TO_IMAGE_STRUCT_NO_STEP</a></div><div class="ttdeci">#define CONVERT_TO_IMAGE_STRUCT_NO_STEP(name)</div><div class="ttdef"><b>Definition:</b> <a href="helpers_8h_source.xhtml#l00076">helpers.h:76</a></div></div>
<div class="ttc" id="helpers_8h_xhtml_a22f42fcf2077d951271df83b55c1a71a"><div class="ttname"><a href="helpers_8h.xhtml#a22f42fcf2077d951271df83b55c1a71a">IMAGE_DECLARATION</a></div><div class="ttdeci">#define IMAGE_DECLARATION(name)</div><div class="ttdef"><b>Definition:</b> <a href="helpers_8h_source.xhtml#l00049">helpers.h:49</a></div></div>
<div id="nav-path" class="navpath"><!-- id is needed for treeview function! -->
<ul>
<li class="navelem"><a class="el" href="dir_68267d1309a1af8e8297ef4c3efbcdba.xhtml">src</a></li><li class="navelem"><a class="el" href="dir_aebb8dcc11953d78e620bbef0b9e2183.xhtml">core</a></li><li class="navelem"><a class="el" href="dir_8c278f79c760e5c5fbd911f9870614c1.xhtml">CL</a></li><li class="navelem"><a class="el" href="dir_25885286e9dad4fa105b7b25a8031bbf.xhtml">cl_kernels</a></li><li class="navelem"><a class="el" href="canny_8cl.xhtml">canny.cl</a></li>
- <li class="footer">Generated on Fri Mar 24 2017 17:23:49 for ARM Compute Library by
+ <li class="footer">Generated on Wed Apr 12 2017 14:26:05 for ARM Compute Library by
<a href="http://www.doxygen.org/index.html">
<img class="footer" src="doxygen.png" alt="doxygen"/></a> 1.8.11 </li>
</ul>
projects / platform / upstream / armcl.git / blobdiff