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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> 89 90<h2><a href="../../api/MagickCore/shear_8c.html" id="DeskewImage">DeskewImage</a></h2> 91 92<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> 93 94<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> 95 96<p>The format of the DeskewImage method is:</p> 97 98<pre class="text"> 99Image *DeskewImage(const Image *image,const double threshold, 100 ExceptionInfo *exception) 101</pre> 102 103<p>A description of each parameter follows:</p> 104 105<dd> 106</dd> 107 108<dd> </dd> 109<dl class="dl-horizontal"> 110<dt>image</dt> 111<dd>the image. </dd> 112 113<dd> </dd> 114<dt>threshold</dt> 115<dd>separate background from foreground. </dd> 116 117<dd> </dd> 118<dt>exception</dt> 119<dd>return any errors or warnings in this structure. </dd> 120 121<dd> </dd> 122</dl> 123<h2><a href="../../api/MagickCore/shear_8c.html" id="IntegralRotateImage">IntegralRotateImage</a></h2> 124 125<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> 126 127<p>The format of the IntegralRotateImage method is:</p> 128 129<pre class="text"> 130Image *IntegralRotateImage(const Image *image,size_t rotations, 131 ExceptionInfo *exception) 132</pre> 133 134<p>A description of each parameter follows.</p> 135 136<dt>image</dt> 137<p>the image.</p> 138 139<dt>rotations</dt> 140<p>Specifies the number of 90 degree rotations.</p> 141 142<h2><a href="../../api/MagickCore/shear_8c.html" id="ShearImage">ShearImage</a></h2> 143 144<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> 145 146<p>ShearImage() is based on the paper "A Fast Algorithm for General Raster Rotatation" by Alan W. Paeth.</p> 147 148<p>The format of the ShearImage method is:</p> 149 150<pre class="text"> 151Image *ShearImage(const Image *image,const double x_shear, 152 const double y_shear,ExceptionInfo *exception) 153</pre> 154 155<p>A description of each parameter follows.</p> 156 157<dt>image</dt> 158<p>the image.</p> 159 160<dt>x_shear, y_shear</dt> 161<p>Specifies the number of degrees to shear the image.</p> 162 163<dt>exception</dt> 164<p>return any errors or warnings in this structure.</p> 165 166<h2><a href="../../api/MagickCore/shear_8c.html" id="ShearRotateImage">ShearRotateImage</a></h2> 167 168<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> 169 170<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> 171 172<p>The format of the ShearRotateImage method is:</p> 173 174<pre class="text"> 175Image *ShearRotateImage(const Image *image,const double degrees, 176 ExceptionInfo *exception) 177</pre> 178 179<p>A description of each parameter follows.</p> 180 181<dt>image</dt> 182<p>the image.</p> 183 184<dt>degrees</dt> 185<p>Specifies the number of degrees to rotate the image.</p> 186 187<dt>exception</dt> 188<p>return any errors or warnings in this structure.</p> 189 190</div> 191 </div> 192 </main><!-- /.container --> 193 <footer class="magick-footer"> 194 <p><a href="../../www/security-policy.html">Security</a> • 195 <a href="../../www/architecture.html">Architecture</a> • 196 <a href="../../www/links.html">Related</a> • 197 <a href="../../www/sitemap.html">Sitemap</a> 198 199 <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> 200 201 <a href="http://pgp.mit.edu/pks/lookup?op=get&search=0x89AB63D48277377A">Public Key</a> • 202 <a href="../../www/support.html">Donate</a> • 203 <a href="../../www/contact.html">Contact Us</a> 204 <br/> 205 <small>© 1999-2019 ImageMagick Studio LLC</small></p> 206 </footer> 207 208 <!-- Javascript assets --> 209 <script src="../assets/magick.js" crossorigin="anonymous"></script> 210 <script>window.jQuery || document.write('<script src="https://localhost/ajax/libs/jquery/3.3.1/jquery.min.js"><\/script>')</script> 211</body> 212</html> 213<!-- Magick Cache 3rd January 2019 05:28 -->
