diff options
Diffstat (limited to 'source/fitz')
| -rw-r--r-- | source/fitz/colorspace.c | 58 |
1 files changed, 57 insertions, 1 deletions
diff --git a/source/fitz/colorspace.c b/source/fitz/colorspace.c index d30f98eb..90539860 100644 --- a/source/fitz/colorspace.c +++ b/source/fitz/colorspace.c @@ -169,20 +169,60 @@ static void rgb_to_cmyk(fz_context *ctx, fz_colorspace *cs, const float *rgb, fl cmyk[3] = k; } +static inline float fung(float x) +{ + if (x >= 6.0f / 29.0f) + return x * x * x; + return (108.0f / 841.0f) * (x - (4.0f / 29.0f)); +} + +static void +lab_to_rgb(fz_context *ctx, fz_colorspace *cs, const float *lab, float *rgb) +{ + /* input is in range (0..100, -128..127, -128..127) not (0..1, 0..1, 0..1) */ + float lstar, astar, bstar, l, m, n, x, y, z, r, g, b; + lstar = lab[0]; + astar = lab[1]; + bstar = lab[2]; + m = (lstar + 16) / 116; + l = m + astar / 500; + n = m - bstar / 200; + x = fung(l); + y = fung(m); + z = fung(n); + r = (3.240449f * x + -1.537136f * y + -0.498531f * z) * 0.830026f; + g = (-0.969265f * x + 1.876011f * y + 0.041556f * z) * 1.05452f; + b = (0.055643f * x + -0.204026f * y + 1.057229f * z) * 1.1003f; + rgb[0] = sqrtf(fz_clamp(r, 0, 1)); + rgb[1] = sqrtf(fz_clamp(g, 0, 1)); + rgb[2] = sqrtf(fz_clamp(b, 0, 1)); +} + +static void +rgb_to_lab(fz_context *ctx, fz_colorspace *cs, const float *rgb, float *lab) +{ + fz_warn(ctx, "cannot convert into L*a*b colorspace"); + lab[0] = rgb[0]; + lab[1] = rgb[1]; + lab[2] = rgb[2]; +} + static fz_colorspace k_default_gray = { {-1, fz_drop_colorspace_imp}, 0, "DeviceGray", 1, gray_to_rgb, rgb_to_gray }; static fz_colorspace k_default_rgb = { {-1, fz_drop_colorspace_imp}, 0, "DeviceRGB", 3, rgb_to_rgb, rgb_to_rgb }; static fz_colorspace k_default_bgr = { {-1, fz_drop_colorspace_imp}, 0, "DeviceBGR", 3, bgr_to_rgb, rgb_to_bgr }; static fz_colorspace k_default_cmyk = { {-1, fz_drop_colorspace_imp}, 0, "DeviceCMYK", 4, cmyk_to_rgb, rgb_to_cmyk }; +static fz_colorspace k_default_lab = { {-1, fz_drop_colorspace_imp}, 0, "Lab", 3, lab_to_rgb, rgb_to_lab }; static fz_colorspace *fz_default_gray = &k_default_gray; static fz_colorspace *fz_default_rgb = &k_default_rgb; static fz_colorspace *fz_default_bgr = &k_default_bgr; static fz_colorspace *fz_default_cmyk = &k_default_cmyk; +static fz_colorspace *fz_default_lab = &k_default_lab; struct fz_colorspace_context_s { int ctx_refs; - fz_colorspace *gray, *rgb, *bgr, *cmyk; + fz_colorspace *gray, *rgb, *bgr, *cmyk, *lab; }; void fz_new_colorspace_context(fz_context *ctx) @@ -193,6 +233,7 @@ void fz_new_colorspace_context(fz_context *ctx) ctx->colorspace->rgb = fz_default_rgb; ctx->colorspace->bgr = fz_default_bgr; ctx->colorspace->cmyk = fz_default_cmyk; + ctx->colorspace->lab = fz_default_lab; } fz_colorspace_context * @@ -235,6 +276,12 @@ fz_device_cmyk(fz_context *ctx) return ctx->colorspace->cmyk; } +fz_colorspace * +fz_device_lab(fz_context *ctx) +{ + return ctx->colorspace->lab; +} + void fz_set_device_gray(fz_context *ctx, fz_colorspace *cs) { @@ -271,6 +318,15 @@ fz_set_device_cmyk(fz_context *ctx, fz_colorspace *cs) fz_unlock(ctx, FZ_LOCK_ALLOC); } +void +fz_set_device_lab(fz_context *ctx, fz_colorspace *cs) +{ + fz_lock(ctx, FZ_LOCK_ALLOC); + fz_drop_colorspace(ctx, ctx->colorspace->lab); + ctx->colorspace->lab = fz_keep_colorspace(ctx, cs); + fz_unlock(ctx, FZ_LOCK_ALLOC); +} + int fz_colorspace_is_indexed(fz_context *ctx, fz_colorspace *cs) { |