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Diffstat (limited to 'Build/source/libs/libpng/libpng-1.6.15/pngwtran.c')
-rw-r--r-- | Build/source/libs/libpng/libpng-1.6.15/pngwtran.c | 574 |
1 files changed, 574 insertions, 0 deletions
diff --git a/Build/source/libs/libpng/libpng-1.6.15/pngwtran.c b/Build/source/libs/libpng/libpng-1.6.15/pngwtran.c new file mode 100644 index 00000000000..09562a787d0 --- /dev/null +++ b/Build/source/libs/libpng/libpng-1.6.15/pngwtran.c @@ -0,0 +1,574 @@ + +/* pngwtran.c - transforms the data in a row for PNG writers + * + * Last changed in libpng 1.6.15 [November 20, 2014] + * Copyright (c) 1998-2014 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 + */ + +#include "pngpriv.h" + +#ifdef PNG_WRITE_SUPPORTED +#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED + +#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). + */ +static void +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 && + 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; + } + + default: + 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. + */ +static void +png_do_shift(png_row_infop row_info, png_bytep row, + png_const_color_8p bit_depth) +{ + png_debug(1, "in png_do_shift"); + + if (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) != 0) + { + 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) != 0) + { + 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_size_t i; + unsigned int mask; + png_size_t 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++) + { + int j; + unsigned int v, out; + + v = *bp; + out = 0; + + for (j = shift_start[0]; j > -shift_dec[0]; j -= shift_dec[0]) + { + if (j > 0) + out |= v << j; + + else + out |= (v >> (-j)) & mask; + } + + *bp = (png_byte)(out & 0xff); + } + } + + 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++) + { + + const unsigned int c = i%channels; + int j; + unsigned int v, out; + + v = *bp; + out = 0; + + for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c]) + { + if (j > 0) + out |= v << j; + + else + out |= v >> (-j); + } + + *bp = (png_byte)(out & 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++) + { + const unsigned int c = i%channels; + int j; + unsigned int value, v; + + v = png_get_uint_16(bp); + value = 0; + + for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c]) + { + if (j > 0) + value |= v << j; + + else + value |= v >> (-j); + } + *bp++ = (png_byte)((value >> 8) & 0xff); + *bp++ = (png_byte)(value & 0xff); + } + } + } +} +#endif + +#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED +static void +png_do_write_swap_alpha(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_write_swap_alpha"); + + { + if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + { + if (row_info->bit_depth == 8) + { + /* This converts from ARGB to RGBA */ + 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; + } + } + +#ifdef PNG_WRITE_16BIT_SUPPORTED + else + { + /* This converts from AARRGGBB to RRGGBBAA */ + 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]; + } + } +#endif /* WRITE_16BIT */ + } + + else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) + { + if (row_info->bit_depth == 8) + { + /* This converts from AG to GA */ + 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; + } + } + +#ifdef PNG_WRITE_16BIT_SUPPORTED + else + { + /* This converts from AAGG to GGAA */ + 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 /* WRITE_16BIT */ + } + } +} +#endif + +#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED +static void +png_do_write_invert_alpha(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_write_invert_alpha"); + + { + if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + { + if (row_info->bit_depth == 8) + { + /* This inverts the alpha channel in RGBA */ + 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++)); + } + } + +#ifdef PNG_WRITE_16BIT_SUPPORTED + else + { + /* This inverts the alpha channel in RRGGBBAA */ + 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++)); + } + } +#endif /* WRITE_16BIT */ + } + + else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) + { + if (row_info->bit_depth == 8) + { + /* This inverts the alpha channel in GA */ + 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++)); + } + } + +#ifdef PNG_WRITE_16BIT_SUPPORTED + else + { + /* This inverts the alpha channel in GGAA */ + 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 /* WRITE_16BIT */ + } + } +} +#endif + +/* Transform the data according to the user's wishes. The order of + * transformations is significant. + */ +void /* PRIVATE */ +png_do_write_transformations(png_structrp png_ptr, png_row_infop row_info) +{ + 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) != 0) + if (png_ptr->write_user_transform_fn != NULL) + (*(png_ptr->write_user_transform_fn)) /* User write transform + function */ + (png_ptr, /* png_ptr */ + row_info, /* row_info: */ + /* png_uint_32 width; width of row */ + /* png_size_t 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) != 0) + png_do_strip_channel(row_info, png_ptr->row_buf + 1, + !(png_ptr->flags & PNG_FLAG_FILLER_AFTER)); +#endif + +#ifdef PNG_WRITE_PACKSWAP_SUPPORTED + if ((png_ptr->transformations & PNG_PACKSWAP) != 0) + png_do_packswap(row_info, png_ptr->row_buf + 1); +#endif + +#ifdef PNG_WRITE_PACK_SUPPORTED + if ((png_ptr->transformations & PNG_PACK) != 0) + png_do_pack(row_info, png_ptr->row_buf + 1, + (png_uint_32)png_ptr->bit_depth); +#endif + +#ifdef PNG_WRITE_SWAP_SUPPORTED +# ifdef PNG_16BIT_SUPPORTED + if ((png_ptr->transformations & PNG_SWAP_BYTES) != 0) + png_do_swap(row_info, png_ptr->row_buf + 1); +# endif +#endif + +#ifdef PNG_WRITE_SHIFT_SUPPORTED + if ((png_ptr->transformations & PNG_SHIFT) != 0) + png_do_shift(row_info, png_ptr->row_buf + 1, + &(png_ptr->shift)); +#endif + +#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED + if ((png_ptr->transformations & PNG_SWAP_ALPHA) != 0) + png_do_write_swap_alpha(row_info, png_ptr->row_buf + 1); +#endif + +#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED + if ((png_ptr->transformations & PNG_INVERT_ALPHA) != 0) + png_do_write_invert_alpha(row_info, png_ptr->row_buf + 1); +#endif + +#ifdef PNG_WRITE_BGR_SUPPORTED + if ((png_ptr->transformations & PNG_BGR) != 0) + png_do_bgr(row_info, png_ptr->row_buf + 1); +#endif + +#ifdef PNG_WRITE_INVERT_SUPPORTED + if ((png_ptr->transformations & PNG_INVERT_MONO) != 0) + png_do_invert(row_info, png_ptr->row_buf + 1); +#endif +} +#endif /* WRITE_TRANSFORMS */ +#endif /* WRITE */ |