diff options
Diffstat (limited to 'raster/imageunpack.c')
| -rw-r--r-- | raster/imageunpack.c | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/raster/imageunpack.c b/raster/imageunpack.c new file mode 100644 index 00000000..0885c293 --- /dev/null +++ b/raster/imageunpack.c @@ -0,0 +1,183 @@ +#include <fitz.h> + +typedef unsigned char byte; + +/* + * Apply decode parameters + */ + +static void decodetile(fz_pixmap *pix, int skip, float *decode) +{ + int min[FZ_MAXCOLORS]; + int max[FZ_MAXCOLORS]; + int sub[FZ_MAXCOLORS]; + int useless = 1; + byte *p = pix->samples; + int n = pix->n; + int wh = pix->w * pix->h; + int i; + + min[0] = 0; + max[0] = 255; + sub[0] = 255; + + for (i = skip; i < n; i++) + { + min[i] = decode[(i - skip) * 2] * 255; + max[i] = decode[(i - skip) * 2 + 1] * 255; + sub[i] = max[i] - min[i]; + if (min[i] != 0 || max[i] != 255) + useless = 0; + } + + if (useless) + return; + + while (wh--) + { + for (i = 0; i < n; i++) + p[i] = min[i] + fz_mul255(sub[i], p[i]); + p += n; + } +} + +/* + * Unpack image samples and optionally pad pixels with opaque alpha + */ + +#define tbit(buf,x) ((buf[x >> 3] >> ( 7 - (x & 7) ) ) & 1 ) * 255 +#define ttwo(buf,x) ((buf[x >> 2] >> ( ( 3 - (x & 3) ) << 1 ) ) & 3 ) * 85 +#define tnib(buf,x) ((buf[x >> 1] >> ( ( 1 - (x & 1) ) << 2 ) ) & 15 ) * 17 +#define toct(buf,x) (buf[x]) + +static byte t1pad0[256][8]; +static byte t1pad1[256][16]; + +static void init1() +{ + static int inited = 0; + byte bits[1]; + int i, k, x; + + if (inited) + return; + + for (i = 0; i < 256; i++) + { + bits[0] = i; + for (k = 0; k < 8; k++) + { + x = tbit(bits, k); + t1pad0[i][k] = x; + t1pad1[i][k * 2 + 0] = 255; + t1pad1[i][k * 2 + 1] = x; + } + } + + inited = 1; +} + +static void loadtile1(byte *src, int sw, byte *dst, int dw, int w, int h, int pad) +{ + byte *sp; + byte *dp; + int x; + + init1(); + + if (pad == 0) + { + int w3 = w >> 3; + while (h--) + { + sp = src; + dp = dst; + for (x = 0; x < w3; x++) + { + memcpy(dp, t1pad0[*sp++], 8); + dp += 8; + } + x = x << 3; + if (x < w) + memcpy(dp, t1pad0[*sp], w - x); + src += sw; + dst += dw; + } + } + + else if (pad == 1) + { + int w3 = w >> 3; + while (h--) + { + sp = src; + dp = dst; + for (x = 0; x < w3; x++) + { + memcpy(dp, t1pad1[*sp++], 16); + dp += 16; + } + x = x << 3; + if (x < w) + memcpy(dp, t1pad1[*sp], (w - x) << 1); + src += sw; + dst += dw; + } + } + + else + { + while (h--) + { + dp = dst; + for (x = 0; x < w; x++) + { + if ((x % pad) == 0) + *dp++ = 255; + *dp++ = tbit(src, x); + } + src += sw; + dst += dw; + } + } +} + +#define TILE(getf) \ +{ \ + int x; \ + if (!pad) \ + while (h--) \ + { \ + for (x = 0; x < w; x++) \ + dst[x] = getf(src, x); \ + src += sw; \ + dst += dw; \ + } \ + else \ + while (h--) \ + { \ + byte *dp = dst; \ + for (x = 0; x < w; x++) \ + { \ + if ((x % pad) == 0) \ + *dp++ = 255; \ + *dp++ = getf(src, x); \ + } \ + src += sw; \ + dst += dw; \ + } \ +} + +static void loadtile2(byte *src, int sw, byte *dst, int dw, int w, int h, int pad) + TILE(ttwo) +static void loadtile4(byte *src, int sw, byte *dst, int dw, int w, int h, int pad) + TILE(tnib) +static void loadtile8(byte *src, int sw, byte *dst, int dw, int w, int h, int pad) + TILE(toct) + +void (*fz_decodetile)(fz_pixmap *pix, int skip, float *decode) = decodetile; +void (*fz_loadtile1)(byte*, int sw, byte*, int dw, int w, int h, int pad) = loadtile1; +void (*fz_loadtile2)(byte*, int sw, byte*, int dw, int w, int h, int pad) = loadtile2; +void (*fz_loadtile4)(byte*, int sw, byte*, int dw, int w, int h, int pad) = loadtile4; +void (*fz_loadtile8)(byte*, int sw, byte*, int dw, int w, int h, int pad) = loadtile8; + |