MATLAB Function Reference (Volume 2: Graphics)

imageimage(x,y,C,'PropertyName',PropertyValue,...) is a high-level functionthat also specifies property name/property value pairs. This syntax callsnewplot before drawing the image.image('PropertyName',PropertyValue,...) is the low-level syntax of theimage function. It specifies only property name/property value pairs as inputarguments.handle = image(...) returns the handle of the image object it creates. Youcan obtain the handle with all forms of the image function.Remarksimage data can be either indexed or true color. An indexed image stores colorsas an array of indices into the figure colormap. A true color image does not usea colormap; instead, the color values for each pixel are stored directly as RGBtriplets. In MATLAB , the CData property of a truecolor image object is athree-dimensional (m-by-n-by-3) array. This array consists of three m-by-nmatrices (representing the red, green, and blue color planes) concatenatedalong the third dimension.The imread function reads image data into MATLAB arrays from graphics filesin various standard formats, such as TIFF. You can write MATLAB image datato graphics files using the imwrite function. imread and imwrite both supporta variety of graphics file formats and compression schemes.When you read image data into MATLAB using imread, the data is usuallystored as an array of 8-bit integers. However, imread also supports reading16-bit-per-pixel data from TIFF and PNG files. These are more efficient storagemethod than the double-precision (64-bit) floating-point numbers thatMATLAB typically uses. However, it is necessary for MATLAB to interpret8-bit and 16-bit image data differently from 64-bit data. This table summarizesthese differences.2-229