Lines Matching defs:dither
55 * We use a standard 16x16 ordered dither array. The basic concept of ordered
59 * "dither" value to the input pixel and then round the result to the nearest
60 * output value. The dither value is equivalent to (0.5 - threshold) times
63 * worse, since the dither may be too much or too little at a given point.
65 * The normal calculation would be to form pixel value + dither, range-limit
71 #define ODITHER_SIZE 16 /* dimension of dither matrix */
80 /* Bayer's order-4 dither array. Generated by the code given in
159 int row_index; /* cur row's vertical index in dither matrix */
160 ODITHER_MATRIX_PTR odither[MAX_Q_COMPS]; /* one dither array per component */
339 /* For ordered dither, we pad the color index tables by MAXJSAMPLE in
391 * Create an ordered-dither array for a component having ncolors
406 * Hence the dither value for the matrix cell with fill order f
426 * Create the ordered-dither tables.
428 * share a dither table.
523 int * dither; /* points to active row of dither matrix */
524 int row_index, col_index; /* current indexes into dither matrix */
540 dither = cquantize->odither[ci][row_index];
544 /* Form pixel value + dither, range-limit to 0..MAXJSAMPLE,
548 * inputs. The maximum dither is +- MAXJSAMPLE; this sets the
551 *output_ptr += colorindex_ci[GETJSAMPLE(*input_ptr)+dither[col_index]];
576 int * dither0; /* points to active row of dither matrix */
579 int row_index, col_index; /* current indexes into dither matrix */
764 cquantize->row_index = 0; /* initialize state for ordered dither */
765 /* If user changed to ordered dither from another mode,
771 /* Create ordered-dither tables if we didn't already. */
777 cquantize->on_odd_row = FALSE; /* initialize state for F-S dither */
848 * manager's space calculations. If the user changes to FS dither