Lines Matching refs:alpha
55 BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file, BOOL raw, BOOL alpha);
67 BOOL alpha = FALSE;
83 alpha = TRUE;
88 fprintf (stderr, "Error: can not create alpha-channel file %s\n", argv[argi]);
145 if (png2pnm (fp_rd, fp_wr, fp_al, raw, alpha) == FALSE)
156 /* close alpha file */
157 if (alpha)
181 fprintf (stderr, " -a[lpha] <file>.pgm write PNG alpha channel as pgm-file\n");
189 BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file, BOOL raw, BOOL alpha)
259 /* transform transparency maps into full alpha-channel */
294 /* calculate new number of channels and store alpha-presence */
307 /* check if alpha is expected to be present in file */
308 if (alpha && !alpha_present)
311 fprintf (stderr, "Error: PNG-file doesn't contain alpha channel\n");
361 /* write header of PGM file with alpha channel */
363 if ((alpha) &&
393 if (!alpha)
395 pix_ptr++; /* alpha */
399 else /* output alpha-channel as pgm file */