diff options
Diffstat (limited to 'contrib/syslinux-4.02/com32/lib/libpng/pngwtran.c')
-rw-r--r-- | contrib/syslinux-4.02/com32/lib/libpng/pngwtran.c | 582 |
1 files changed, 582 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/com32/lib/libpng/pngwtran.c b/contrib/syslinux-4.02/com32/lib/libpng/pngwtran.c new file mode 100644 index 0000000..0ce9b9b --- /dev/null +++ b/contrib/syslinux-4.02/com32/lib/libpng/pngwtran.c @@ -0,0 +1,582 @@ + +/* pngwtran.c - transforms the data in a row for PNG writers + * + * Last changed in libpng 1.2.43 [February 25, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + */ + +#define PNG_INTERNAL +#define PNG_NO_PEDANTIC_WARNINGS +#include "png.h" +#ifdef PNG_WRITE_SUPPORTED + +/* Transform the data according to the user's wishes. The order of + * transformations is significant. + */ +void /* PRIVATE */ +png_do_write_transformations(png_structp png_ptr) +{ + png_debug(1, "in png_do_write_transformations"); + + if (png_ptr == NULL) + return; + +#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED + if (png_ptr->transformations & PNG_USER_TRANSFORM) + if (png_ptr->write_user_transform_fn != NULL) + (*(png_ptr->write_user_transform_fn)) /* User write transform + function */ + (png_ptr, /* png_ptr */ + &(png_ptr->row_info), /* row_info: */ + /* png_uint_32 width; width of row */ + /* png_uint_32 rowbytes; number of bytes in row */ + /* png_byte color_type; color type of pixels */ + /* png_byte bit_depth; bit depth of samples */ + /* png_byte channels; number of channels (1-4) */ + /* png_byte pixel_depth; bits per pixel (depth*channels) */ + png_ptr->row_buf + 1); /* start of pixel data for row */ +#endif +#ifdef PNG_WRITE_FILLER_SUPPORTED + if (png_ptr->transformations & PNG_FILLER) + png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1, + png_ptr->flags); +#endif +#ifdef PNG_WRITE_PACKSWAP_SUPPORTED + if (png_ptr->transformations & PNG_PACKSWAP) + png_do_packswap(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif +#ifdef PNG_WRITE_PACK_SUPPORTED + if (png_ptr->transformations & PNG_PACK) + png_do_pack(&(png_ptr->row_info), png_ptr->row_buf + 1, + (png_uint_32)png_ptr->bit_depth); +#endif +#ifdef PNG_WRITE_SWAP_SUPPORTED + if (png_ptr->transformations & PNG_SWAP_BYTES) + png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif +#ifdef PNG_WRITE_SHIFT_SUPPORTED + if (png_ptr->transformations & PNG_SHIFT) + png_do_shift(&(png_ptr->row_info), png_ptr->row_buf + 1, + &(png_ptr->shift)); +#endif +#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED + if (png_ptr->transformations & PNG_SWAP_ALPHA) + png_do_write_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif +#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED + if (png_ptr->transformations & PNG_INVERT_ALPHA) + png_do_write_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif +#ifdef PNG_WRITE_BGR_SUPPORTED + if (png_ptr->transformations & PNG_BGR) + png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif +#ifdef PNG_WRITE_INVERT_SUPPORTED + if (png_ptr->transformations & PNG_INVERT_MONO) + png_do_invert(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif +} + +#ifdef PNG_WRITE_PACK_SUPPORTED +/* Pack pixels into bytes. Pass the true bit depth in bit_depth. The + * row_info bit depth should be 8 (one pixel per byte). The channels + * should be 1 (this only happens on grayscale and paletted images). + */ +void /* PRIVATE */ +png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth) +{ + png_debug(1, "in png_do_pack"); + + if (row_info->bit_depth == 8 && +#ifdef PNG_USELESS_TESTS_SUPPORTED + row != NULL && row_info != NULL && +#endif + row_info->channels == 1) + { + switch ((int)bit_depth) + { + case 1: + { + png_bytep sp, dp; + int mask, v; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + sp = row; + dp = row; + mask = 0x80; + v = 0; + + for (i = 0; i < row_width; i++) + { + if (*sp != 0) + v |= mask; + sp++; + if (mask > 1) + mask >>= 1; + else + { + mask = 0x80; + *dp = (png_byte)v; + dp++; + v = 0; + } + } + if (mask != 0x80) + *dp = (png_byte)v; + break; + } + case 2: + { + png_bytep sp, dp; + int shift, v; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + sp = row; + dp = row; + shift = 6; + v = 0; + for (i = 0; i < row_width; i++) + { + png_byte value; + + value = (png_byte)(*sp & 0x03); + v |= (value << shift); + if (shift == 0) + { + shift = 6; + *dp = (png_byte)v; + dp++; + v = 0; + } + else + shift -= 2; + sp++; + } + if (shift != 6) + *dp = (png_byte)v; + break; + } + case 4: + { + png_bytep sp, dp; + int shift, v; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + sp = row; + dp = row; + shift = 4; + v = 0; + for (i = 0; i < row_width; i++) + { + png_byte value; + + value = (png_byte)(*sp & 0x0f); + v |= (value << shift); + + if (shift == 0) + { + shift = 4; + *dp = (png_byte)v; + dp++; + v = 0; + } + else + shift -= 4; + + sp++; + } + if (shift != 4) + *dp = (png_byte)v; + break; + } + } + row_info->bit_depth = (png_byte)bit_depth; + row_info->pixel_depth = (png_byte)(bit_depth * row_info->channels); + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, + row_info->width); + } +} +#endif + +#ifdef PNG_WRITE_SHIFT_SUPPORTED +/* Shift pixel values to take advantage of whole range. Pass the + * true number of bits in bit_depth. The row should be packed + * according to row_info->bit_depth. Thus, if you had a row of + * bit depth 4, but the pixels only had values from 0 to 7, you + * would pass 3 as bit_depth, and this routine would translate the + * data to 0 to 15. + */ +void /* PRIVATE */ +png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth) +{ + png_debug(1, "in png_do_shift"); + +#ifdef PNG_USELESS_TESTS_SUPPORTED + if (row != NULL && row_info != NULL && +#else + if ( +#endif + row_info->color_type != PNG_COLOR_TYPE_PALETTE) + { + int shift_start[4], shift_dec[4]; + int channels = 0; + + if (row_info->color_type & PNG_COLOR_MASK_COLOR) + { + shift_start[channels] = row_info->bit_depth - bit_depth->red; + shift_dec[channels] = bit_depth->red; + channels++; + shift_start[channels] = row_info->bit_depth - bit_depth->green; + shift_dec[channels] = bit_depth->green; + channels++; + shift_start[channels] = row_info->bit_depth - bit_depth->blue; + shift_dec[channels] = bit_depth->blue; + channels++; + } + else + { + shift_start[channels] = row_info->bit_depth - bit_depth->gray; + shift_dec[channels] = bit_depth->gray; + channels++; + } + if (row_info->color_type & PNG_COLOR_MASK_ALPHA) + { + shift_start[channels] = row_info->bit_depth - bit_depth->alpha; + shift_dec[channels] = bit_depth->alpha; + channels++; + } + + /* With low row depths, could only be grayscale, so one channel */ + if (row_info->bit_depth < 8) + { + png_bytep bp = row; + png_uint_32 i; + png_byte mask; + png_uint_32 row_bytes = row_info->rowbytes; + + if (bit_depth->gray == 1 && row_info->bit_depth == 2) + mask = 0x55; + else if (row_info->bit_depth == 4 && bit_depth->gray == 3) + mask = 0x11; + else + mask = 0xff; + + for (i = 0; i < row_bytes; i++, bp++) + { + png_uint_16 v; + int j; + + v = *bp; + *bp = 0; + for (j = shift_start[0]; j > -shift_dec[0]; j -= shift_dec[0]) + { + if (j > 0) + *bp |= (png_byte)((v << j) & 0xff); + else + *bp |= (png_byte)((v >> (-j)) & mask); + } + } + } + else if (row_info->bit_depth == 8) + { + png_bytep bp = row; + png_uint_32 i; + png_uint_32 istop = channels * row_info->width; + + for (i = 0; i < istop; i++, bp++) + { + + png_uint_16 v; + int j; + int c = (int)(i%channels); + + v = *bp; + *bp = 0; + for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c]) + { + if (j > 0) + *bp |= (png_byte)((v << j) & 0xff); + else + *bp |= (png_byte)((v >> (-j)) & 0xff); + } + } + } + else + { + png_bytep bp; + png_uint_32 i; + png_uint_32 istop = channels * row_info->width; + + for (bp = row, i = 0; i < istop; i++) + { + int c = (int)(i%channels); + png_uint_16 value, v; + int j; + + v = (png_uint_16)(((png_uint_16)(*bp) << 8) + *(bp + 1)); + value = 0; + for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c]) + { + if (j > 0) + value |= (png_uint_16)((v << j) & (png_uint_16)0xffff); + else + value |= (png_uint_16)((v >> (-j)) & (png_uint_16)0xffff); + } + *bp++ = (png_byte)(value >> 8); + *bp++ = (png_byte)(value & 0xff); + } + } + } +} +#endif + +#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED +void /* PRIVATE */ +png_do_write_swap_alpha(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_write_swap_alpha"); + +#ifdef PNG_USELESS_TESTS_SUPPORTED + if (row != NULL && row_info != NULL) +#endif + { + if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + { + /* This converts from ARGB to RGBA */ + if (row_info->bit_depth == 8) + { + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + for (i = 0, sp = dp = row; i < row_width; i++) + { + png_byte save = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = save; + } + } + /* This converts from AARRGGBB to RRGGBBAA */ + else + { + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + for (i = 0, sp = dp = row; i < row_width; i++) + { + png_byte save[2]; + save[0] = *(sp++); + save[1] = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = save[0]; + *(dp++) = save[1]; + } + } + } + else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) + { + /* This converts from AG to GA */ + if (row_info->bit_depth == 8) + { + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + for (i = 0, sp = dp = row; i < row_width; i++) + { + png_byte save = *(sp++); + *(dp++) = *(sp++); + *(dp++) = save; + } + } + /* This converts from AAGG to GGAA */ + else + { + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + for (i = 0, sp = dp = row; i < row_width; i++) + { + png_byte save[2]; + save[0] = *(sp++); + save[1] = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = save[0]; + *(dp++) = save[1]; + } + } + } + } +} +#endif + +#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED +void /* PRIVATE */ +png_do_write_invert_alpha(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_write_invert_alpha"); + +#ifdef PNG_USELESS_TESTS_SUPPORTED + if (row != NULL && row_info != NULL) +#endif + { + if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + { + /* This inverts the alpha channel in RGBA */ + if (row_info->bit_depth == 8) + { + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + for (i = 0, sp = dp = row; i < row_width; i++) + { + /* Does nothing + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + */ + sp+=3; dp = sp; + *(dp++) = (png_byte)(255 - *(sp++)); + } + } + /* This inverts the alpha channel in RRGGBBAA */ + else + { + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + for (i = 0, sp = dp = row; i < row_width; i++) + { + /* Does nothing + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + */ + sp+=6; dp = sp; + *(dp++) = (png_byte)(255 - *(sp++)); + *(dp++) = (png_byte)(255 - *(sp++)); + } + } + } + else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) + { + /* This inverts the alpha channel in GA */ + if (row_info->bit_depth == 8) + { + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + for (i = 0, sp = dp = row; i < row_width; i++) + { + *(dp++) = *(sp++); + *(dp++) = (png_byte)(255 - *(sp++)); + } + } + /* This inverts the alpha channel in GGAA */ + else + { + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + for (i = 0, sp = dp = row; i < row_width; i++) + { + /* Does nothing + *(dp++) = *(sp++); + *(dp++) = *(sp++); + */ + sp+=2; dp = sp; + *(dp++) = (png_byte)(255 - *(sp++)); + *(dp++) = (png_byte)(255 - *(sp++)); + } + } + } + } +} +#endif + +#ifdef PNG_MNG_FEATURES_SUPPORTED +/* Undoes intrapixel differencing */ +void /* PRIVATE */ +png_do_write_intrapixel(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_write_intrapixel"); + + if ( +#ifdef PNG_USELESS_TESTS_SUPPORTED + row != NULL && row_info != NULL && +#endif + (row_info->color_type & PNG_COLOR_MASK_COLOR)) + { + int bytes_per_pixel; + png_uint_32 row_width = row_info->width; + if (row_info->bit_depth == 8) + { + png_bytep rp; + png_uint_32 i; + + if (row_info->color_type == PNG_COLOR_TYPE_RGB) + bytes_per_pixel = 3; + else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + bytes_per_pixel = 4; + else + return; + + for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel) + { + *(rp) = (png_byte)((*rp - *(rp+1))&0xff); + *(rp+2) = (png_byte)((*(rp+2) - *(rp+1))&0xff); + } + } + else if (row_info->bit_depth == 16) + { + png_bytep rp; + png_uint_32 i; + + if (row_info->color_type == PNG_COLOR_TYPE_RGB) + bytes_per_pixel = 6; + else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + bytes_per_pixel = 8; + else + return; + + for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel) + { + png_uint_32 s0 = (*(rp ) << 8) | *(rp+1); + png_uint_32 s1 = (*(rp+2) << 8) | *(rp+3); + png_uint_32 s2 = (*(rp+4) << 8) | *(rp+5); + png_uint_32 red = (png_uint_32)((s0 - s1) & 0xffffL); + png_uint_32 blue = (png_uint_32)((s2 - s1) & 0xffffL); + *(rp ) = (png_byte)((red >> 8) & 0xff); + *(rp+1) = (png_byte)(red & 0xff); + *(rp+4) = (png_byte)((blue >> 8) & 0xff); + *(rp+5) = (png_byte)(blue & 0xff); + } + } + } +} +#endif /* PNG_MNG_FEATURES_SUPPORTED */ +#endif /* PNG_WRITE_SUPPORTED */ |