[RGB,alpha] = readRGBATile(row,col)
[RGB,alpha] = readRGBATile(row,col) reads a tile using the RGBA interface. row and col are the one-based row and column numbers of any pixel in the requested tile. RGB consists of an m-by-n-by-3 colormetric image, where m and n are the height and width of the tile, respectively. alpha is the associated alpha matting. If the image does not have associated alpha matting, then alpha is a matrix with all values set to 255 (transparent).
The tile is clipped if the tile boundaries extend past the edges of the image.
The pixel values may be transformed depending upon the values of the following tags:
Open a Tiff object and read the first tile using the RGBA interface.
t = Tiff('example.tif','r'); t.setDirectory(1); [RGB,A] = t.readRGBATile(1,1); t.close();
This method corresponds to the TIFFReadRGBATile function in the LibTIFF C API.
To use this method, you must be familiar with LibTIFF version 4.0.0, as well as the TIFF specification and technical notes. View this documentation at LibTiff - TIFF Library and Utilities.