diff options
Diffstat (limited to 'lib/libpnm3.c')
-rw-r--r-- | lib/libpnm3.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/lib/libpnm3.c b/lib/libpnm3.c index 80ccadfa..c7951546 100644 --- a/lib/libpnm3.c +++ b/lib/libpnm3.c @@ -345,3 +345,45 @@ xeltopixel(xel const inputxel) { PNM_GET1(inputxel), PNM_GET1(inputxel), PNM_GET1(inputxel)); return outputpixel; } + + + +xel +pnm_parsecolorxel(const char * const colorName, + xelval const maxval, + int const format) { + + pixel const bgColor = ppm_parsecolor(colorName, maxval); + + xel retval; + + switch(PNM_FORMAT_TYPE(format)) { + case PPM_TYPE: + PNM_ASSIGN(retval, + PPM_GETR(bgColor), PPM_GETG(bgColor), PPM_GETB(bgColor)); + break; + case PGM_TYPE: + if (PPM_ISGRAY(bgColor)) + PNM_ASSIGN1(retval, PPM_GETB(bgColor)); + else + pm_error("Non-gray color '%s' specified for a " + "grayscale (PGM) image", + colorName); + break; + case PBM_TYPE: + if (PPM_EQUAL(bgColor, ppm_whitepixel(maxval))) + PNM_ASSIGN1(retval, maxval); + else if (PPM_EQUAL(bgColor, ppm_blackpixel())) + PNM_ASSIGN1(retval, 0); + else + pm_error ("Color '%s', which is neither black nor white, " + "specified for a black and white (PBM) image", + colorName); + break; + default: + pm_error("Invalid format code %d passed to pnm_parsecolor()", + format); + } + + return retval; +} |