Lines Matching refs:pixel
125 <p>GetAuthenticPixels() obtains a pixel region for read/write access. If the region is successfully accessed, a pointer to a Quantum array representing the region is returned, otherwise NULL is returned.</p>
161 <p>GetOneAuthenticPixel() returns a single pixel at the specified (x,y) location. The image background color is returned if an error occurs.</p>
167 const ssize_t y,Quantum *pixel,ExceptionInfo *exception)
182 <dd> These values define the location of the pixel to return. </dd>
185 <dt>pixel</dt>
186 <dd>return a pixel at the specified (x,y) location. </dd>
196 <p>GetOneVirtualPixel() returns a single virtual pixel at the specified (x,y) location. The image background color is returned if an error occurs. If you plan to modify the pixel, use GetOneAuthenticPixel() instead.</p>
202 const ssize_t y,Quantum *pixel,ExceptionInfo exception)
217 <dd> These values define the location of the pixel to return. </dd>
220 <dt>pixel</dt>
221 <dd>return a pixel at the specified (x,y) location. </dd>
231 <p>GetOneVirtualPixelInfo() returns a single pixel at the specified (x,y) location. The image background color is returned if an error occurs. If you plan to modify the pixel, use GetOneAuthenticPixel() instead.</p>
238 const ssize_t y,PixelInfo *pixel,ExceptionInfo exception)
253 <dd>the virtual pixel method. </dd>
257 <dd> these values define the location of the pixel to return. </dd>
260 <dt>pixel</dt>
261 <dd>return a pixel at the specified (x,y) location. </dd>
315 <p>GetVirtualPixels() returns an immutable pixel region. If the region is successfully accessed, a pointer to it is returned, otherwise NULL is returned. The returned pointer may point to a temporary working copy of the pixels or it may point to the original pixels in memory. Performance is maximized if the selected region is part of one row, or one or more full rows, since there is opportunity to access the pixels in-place (without a copy) if the image is in memory, or in a memory-mapped file. The returned pointer must *never* be deallocated by the user.</p>
353 <p>QueueAuthenticPixels() queues a mutable pixel region. If the region is successfully initialized a pointer to a Quantum array representing the region is returned, otherwise NULL is returned. The returned pointer may point to a temporary working buffer for the pixels or it may point to the final location of the pixels in memory.</p>
355 <p>Write-only access means that any existing pixel values corresponding to the region are ignored. This is useful if the initial image is being created from scratch, or if the existing pixel values are to be completely replaced without need to refer to their pre-existing values. The application is free to read and write the pixel buffer returned by QueueAuthenticPixels() any way it pleases. QueueAuthenticPixels() does not initialize the pixel array values. Initializing pixel array values is the application's responsibility.</p>
391 <p>SetPixelCacheVirtualMethod() sets the "virtual pixels" method for the pixel cache and returns the previous setting. A virtual pixel is any pixel access that is outside the boundaries of the image cache.</p>
412 <dd>choose the type of virtual pixel. </dd>
422 <p>SyncAuthenticPixels() saves the image pixels to the in-memory or disk cache. The method returns MagickTrue if the pixel region is flushed, otherwise MagickFalse.</p>
