he symbols <samp>i</samp> and <samp>j</samp> reference the current pixel being processed.</p>


<p>For use with <a href="command-line-options.html#format_identify_">-format</a>, the value-escape <samp>%[fx:]</samp> is evaluated just once for each image in the current image sequence. As each image in the sequence is being evaluated, <samp>s</samp> and <samp>t</samp> successively refer to the current image and its index, while <samp>i</samp> and <samp>j</samp> are set to zero, and the current channel set to r