diff options
Diffstat (limited to 'drivers/png/pngtrans.c')
| -rw-r--r-- | drivers/png/pngtrans.c | 115 |
1 files changed, 109 insertions, 6 deletions
diff --git a/drivers/png/pngtrans.c b/drivers/png/pngtrans.c index 6a6908dcd2..a5df5afe00 100644 --- a/drivers/png/pngtrans.c +++ b/drivers/png/pngtrans.c @@ -1,8 +1,8 @@ /* pngtrans.c - transforms the data in a row (used by both readers and writers) * - * Last changed in libpng 1.5.4 [July 7, 2011] - * Copyright (c) 1998-2011 Glenn Randers-Pehrson + * Last changed in libpng 1.5.19 [August 21, 2014] + * Copyright (c) 1998-2002,2004,2006-2014 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.) * @@ -452,7 +452,7 @@ png_do_strip_channel(png_row_infop row_info, png_bytep row, int at_start) { if (row_info->bit_depth == 8) { - if (at_start) /* Skip initial filler */ + if (at_start != 0) /* Skip initial filler */ ++sp; else /* Skip initial channel and, for sp, the filler */ sp += 2, ++dp; @@ -466,7 +466,7 @@ png_do_strip_channel(png_row_infop row_info, png_bytep row, int at_start) else if (row_info->bit_depth == 16) { - if (at_start) /* Skip initial filler */ + if (at_start != 0) /* Skip initial filler */ sp += 2; else /* Skip initial channel and, for sp, the filler */ sp += 4, dp += 2; @@ -492,7 +492,7 @@ png_do_strip_channel(png_row_infop row_info, png_bytep row, int at_start) { if (row_info->bit_depth == 8) { - if (at_start) /* Skip initial filler */ + if (at_start != 0) /* Skip initial filler */ ++sp; else /* Skip initial channels and, for sp, the filler */ sp += 4, dp += 3; @@ -506,7 +506,7 @@ png_do_strip_channel(png_row_infop row_info, png_bytep row, int at_start) else if (row_info->bit_depth == 16) { - if (at_start) /* Skip initial filler */ + if (at_start != 0) /* Skip initial filler */ sp += 2; else /* Skip initial channels and, for sp, the filler */ sp += 8, dp += 6; @@ -619,6 +619,109 @@ png_do_bgr(png_row_infop row_info, png_bytep row) } #endif /* PNG_READ_BGR_SUPPORTED or PNG_WRITE_BGR_SUPPORTED */ +#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \ + defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED) +/* Added at libpng-1.5.10 */ +void /* PRIVATE */ +png_do_check_palette_indexes(png_structp png_ptr, png_row_infop row_info) +{ + if (png_ptr->num_palette < (1 << row_info->bit_depth) && + png_ptr->num_palette > 0) /* num_palette can be 0 in MNG files */ + { + /* Calculations moved outside switch in an attempt to stop different + * compiler warnings. 'padding' is in *bits* within the last byte, it is + * an 'int' because pixel_depth becomes an 'int' in the expression below, + * and this calculation is used because it avoids warnings that other + * forms produced on either GCC or MSVC. + */ + int padding = (-row_info->pixel_depth * row_info->width) & 7; + png_bytep rp = png_ptr->row_buf + row_info->rowbytes; + + switch (row_info->bit_depth) + { + case 1: + { + /* in this case, all bytes must be 0 so we don't need + * to unpack the pixels except for the rightmost one. + */ + for (; rp > png_ptr->row_buf; rp--) + { + if (*rp >> padding != 0) + png_ptr->num_palette_max = 1; + padding = 0; + } + + break; + } + + case 2: + { + for (; rp > png_ptr->row_buf; rp--) + { + int i = ((*rp >> padding) & 0x03); + + if (i > png_ptr->num_palette_max) + png_ptr->num_palette_max = i; + + i = (((*rp >> padding) >> 2) & 0x03); + + if (i > png_ptr->num_palette_max) + png_ptr->num_palette_max = i; + + i = (((*rp >> padding) >> 4) & 0x03); + + if (i > png_ptr->num_palette_max) + png_ptr->num_palette_max = i; + + i = (((*rp >> padding) >> 6) & 0x03); + + if (i > png_ptr->num_palette_max) + png_ptr->num_palette_max = i; + + padding = 0; + } + + break; + } + + case 4: + { + for (; rp > png_ptr->row_buf; rp--) + { + int i = ((*rp >> padding) & 0x0f); + + if (i > png_ptr->num_palette_max) + png_ptr->num_palette_max = i; + + i = (((*rp >> padding) >> 4) & 0x0f); + + if (i > png_ptr->num_palette_max) + png_ptr->num_palette_max = i; + + padding = 0; + } + + break; + } + + case 8: + { + for (; rp > png_ptr->row_buf; rp--) + { + if (*rp > png_ptr->num_palette_max) + png_ptr->num_palette_max = (int) *rp; + } + + break; + } + + default: + break; + } + } +} +#endif /* PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED */ + #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) #ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED |