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Paeth, Graphics Interface '86 (Vancouver). ShearRotateImage() is adapted from a similar method based on the Paeth paper written by Michael Halle of the Spatial Imaging Group, MIT Media Lab.</p> 99 100<h2><a href="../../api/MagickCore/shear_8c.html" id="DeskewImage">DeskewImage</a></h2> 101 102<p>DeskewImage() removes skew from the image. Skew is an artifact that occurs in scanned images because of the camera being misaligned, imperfections in the scanning or surface, or simply because the paper was not placed completely flat when scanned.</p> 103 104<p>The result will be auto-croped if the artifact "deskew:auto-crop" is defined, while the amount the image is to be deskewed, in degrees is also saved as the artifact "deskew:angle".</p> 105 106<p>The format of the DeskewImage method is:</p> 107 108<pre class="text"> 109Image *DeskewImage(const Image *image,const double threshold, 110 ExceptionInfo *exception) 111</pre> 112 113<p>A description of each parameter follows:</p> 114 115<dd> 116</dd> 117 118<dd> </dd> 119<dl class="dl-horizontal"> 120<dt>image</dt> 121<dd>the image. </dd> 122 123<dd> </dd> 124<dt>threshold</dt> 125<dd>separate background from foreground. </dd> 126 127<dd> </dd> 128<dt>exception</dt> 129<dd>return any errors or warnings in this structure. </dd> 130 131<dd> </dd> 132</dl> 133<h2><a href="../../api/MagickCore/shear_8c.html" id="IntegralRotateImage">IntegralRotateImage</a></h2> 134 135<p>IntegralRotateImage() rotates the image an integral of 90 degrees. It allocates the memory necessary for the new Image structure and returns a pointer to the rotated image.</p> 136 137<p>The format of the IntegralRotateImage method is:</p> 138 139<pre class="text"> 140Image *IntegralRotateImage(const Image *image,size_t rotations, 141 ExceptionInfo *exception) 142</pre> 143 144<p>A description of each parameter follows.</p> 145 146<dt>image</dt> 147<p>the image.</p> 148 149<dt>rotations</dt> 150<p>Specifies the number of 90 degree rotations.</p> 151 152<h2><a href="../../api/MagickCore/shear_8c.html" id="ShearImage">ShearImage</a></h2> 153 154<p>ShearImage() creates a new image that is a shear_image copy of an existing one. Shearing slides one edge of an image along the X or Y axis, creating a parallelogram. An X direction shear slides an edge along the X axis, while a Y direction shear slides an edge along the Y axis. The amount of the shear is controlled by a shear angle. For X direction shears, x_shear is measured relative to the Y axis, and similarly, for Y direction shears y_shear is measured relative to the X axis. Empty triangles left over from shearing the image are filled with the background color defined by member 'background_color' of the image.. ShearImage() allocates the memory necessary for the new Image structure and returns a pointer to the new image.</p> 155 156<p>ShearImage() is based on the paper "A Fast Algorithm for General Raster Rotatation" by Alan W. Paeth.</p> 157 158<p>The format of the ShearImage method is:</p> 159 160<pre class="text"> 161Image *ShearImage(const Image *image,const double x_shear, 162 const double y_shear,ExceptionInfo *exception) 163</pre> 164 165<p>A description of each parameter follows.</p> 166 167<dt>image</dt> 168<p>the image.</p> 169 170<dt>x_shear, y_shear</dt> 171<p>Specifies the number of degrees to shear the image.</p> 172 173<dt>exception</dt> 174<p>return any errors or warnings in this structure.</p> 175 176<h2><a href="../../api/MagickCore/shear_8c.html" id="ShearRotateImage">ShearRotateImage</a></h2> 177 178<p>ShearRotateImage() creates a new image that is a rotated copy of an existing one. Positive angles rotate counter-clockwise (right-hand rule), while negative angles rotate clockwise. Rotated images are usually larger than the originals and have 'empty' triangular corners. X axis. Empty triangles left over from shearing the image are filled with the background color defined by member 'background_color' of the image. ShearRotateImage allocates the memory necessary for the new Image structure and returns a pointer to the new image.</p> 179 180<p>ShearRotateImage() is based on the paper "A Fast Algorithm for General Raster Rotatation" by Alan W. Paeth. ShearRotateImage is adapted from a similar method based on the Paeth paper written by Michael Halle of the Spatial Imaging Group, MIT Media Lab.</p> 181 182<p>The format of the ShearRotateImage method is:</p> 183 184<pre class="text"> 185Image *ShearRotateImage(const Image *image,const double degrees, 186 ExceptionInfo *exception) 187</pre> 188 189<p>A description of each parameter follows.</p> 190 191<dt>image</dt> 192<p>the image.</p> 193 194<dt>degrees</dt> 195<p>Specifies the number of degrees to rotate the image.</p> 196 197<dt>exception</dt> 198<p>return any errors or warnings in this structure.</p> 199 200</div> 201 </div> 202 </main><!-- /.container --> 203 <footer class="magick-footer"> 204 <div class="container-fluid"> 205 <a href="../../www/security-policy.html">Security</a> • 206 <a href="../../www/news.html">News</a> 207 208 <a href="shear.html#"><img class="d-inline" id="wand" alt="And Now a Touch of Magick" width="16" height="16" src="../../../images/wand.ico"/></a> 209 210 <a href="../../www/links.html">Related</a> • 211 <a href="../../www/sitemap.html">Sitemap</a> 212 <br/> 213 <a href="../../www/support.html">Sponsor</a> • 214 <a href="../../www/cite.html">Cite</a> • 215 <a href="http://pgp.mit.edu/pks/lookup?op=get&search=0x89AB63D48277377A">Public Key</a> • 216 <a href="../../www/contact.html">Contact Us</a> 217 <br/> 218 <a href="https://github.com/imagemagick/imagemagick" target="_blank" rel="noopener" aria-label="GitHub"><svg xmlns="http://www.w3.org/2000/svg" class="navbar-nav-svg" viewBox="0 0 512 499.36" width="2%" height="2%" role="img" focusable="false"><title>GitHub</title><path fill="currentColor" fill-rule="evenodd" d="M256 0C114.64 0 0 114.61 0 256c0 113.09 73.34 209 175.08 242.9 12.8 2.35 17.47-5.56 17.47-12.34 0-6.08-.22-22.18-.35-43.54-71.2 15.49-86.2-34.34-86.2-34.34-11.64-29.57-28.42-37.45-28.42-37.45-23.27-15.84 1.73-15.55 1.73-15.55 25.69 1.81 39.21 26.38 39.21 26.38 22.84 39.12 59.92 27.82 74.5 21.27 2.33-16.54 8.94-27.82 16.25-34.22-56.84-6.43-116.6-28.43-116.6-126.49 0-27.95 10-50.8 26.35-68.69-2.63-6.48-11.42-32.5 2.51-67.75 0 0 21.49-6.88 70.4 26.24a242.65 242.65 0 0 1 128.18 0c48.87-33.13 70.33-26.24 70.33-26.24 14 35.25 5.18 61.27 2.55 67.75 16.41 17.9 26.31 40.75 26.31 68.69 0 98.35-59.85 120-116.88 126.32 9.19 7.9 17.38 23.53 17.38 47.41 0 34.22-.31 61.83-.31 70.23 0 6.85 4.61 14.81 17.6 12.31C438.72 464.97 512 369.08 512 256.02 512 114.62 397.37 0 256 0z"/></svg></a> • 219 <a href="https://twitter.com/imagemagick" target="_blank" rel="noopener" aria-label="Twitter"><svg xmlns="http://www.w3.org/2000/svg" class="navbar-nav-svg" viewBox="0 0 512 416.32" width="2%" height="2%" role="img" focusable="false"><title>Twitter</title><path fill="currentColor" d="M160.83 416.32c193.2 0 298.92-160.22 298.92-298.92 0-4.51 0-9-.2-13.52A214 214 0 0 0 512 49.38a212.93 212.93 0 0 1-60.44 16.6 105.7 105.7 0 0 0 46.3-58.19 209 209 0 0 1-66.79 25.37 105.09 105.09 0 0 0-181.73 71.91 116.12 116.12 0 0 0 2.66 24c-87.28-4.3-164.73-46.3-216.56-109.82A105.48 105.48 0 0 0 68 159.6a106.27 106.27 0 0 1-47.53-13.11v1.43a105.28 105.28 0 0 0 84.21 103.06 105.67 105.67 0 0 1-47.33 1.84 105.06 105.06 0 0 0 98.14 72.94A210.72 210.72 0 0 1 25 370.84a202.17 202.17 0 0 1-25-1.43 298.85 298.85 0 0 0 160.83 46.92"/></svg></a> 220 <br/> 221 <small>© 1999-2021 ImageMagick Studio LLC</small> 222 </div> 223 </footer> 224 225 <!-- Javascript assets --> 226 <script src="../../assets/magick.js" ></script> 227 </body> 228</html> 229
