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[libpng16] Minor cleanup of iCCP processing
This commit is contained in:
John Bowler
Glenn Randers-Pehrson
parent
702053d110
commit
8010217201
1450
Makefile.in_1_11_2
1450
Makefile.in_1_11_2
File diff suppressed because it is too large
Load Diff
55
png.c
55
png.c
@ -749,13 +749,13 @@ png_get_copyright(png_const_structrp png_ptr)
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#else
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# ifdef __STDC__
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return PNG_STRING_NEWLINE \
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"libpng version 1.6.0beta28 - August 18, 2012" PNG_STRING_NEWLINE \
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"libpng version 1.6.0beta28 - August 22, 2012" PNG_STRING_NEWLINE \
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"Copyright (c) 1998-2012 Glenn Randers-Pehrson" PNG_STRING_NEWLINE \
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"Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
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"Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc." \
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PNG_STRING_NEWLINE;
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# else
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return "libpng version 1.6.0beta28 - August 18, 2012\
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return "libpng version 1.6.0beta28 - August 22, 2012\
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Copyright (c) 1998-2012 Glenn Randers-Pehrson\
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Copyright (c) 1996-1997 Andreas Dilger\
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Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.";
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@ -1028,10 +1028,6 @@ png_colorspace_sync_info(png_const_structrp png_ptr, png_inforp info_ptr)
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else
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info_ptr->valid &= ~PNG_INFO_cHRM;
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/* TODO: at present it is possible to png_set a detectably inconsistent
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* ICC profile, this should be handled, somehow.
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*/
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# endif
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if (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_GAMMA)
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@ -1619,7 +1615,8 @@ png_colorspace_set_xy_and_XYZ(png_const_structrp png_ptr,
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colorspace->flags |= PNG_COLORSPACE_ENDPOINTS_MATCH_sRGB;
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else
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colorspace->flags &= 0xff ^ PNG_COLORSPACE_ENDPOINTS_MATCH_sRGB;
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colorspace->flags &= PNG_COLORSPACE_CANCEL(
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PNG_COLORSPACE_ENDPOINTS_MATCH_sRGB);
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return 2; /* ok and changed */
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}
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@ -1948,12 +1945,25 @@ png_icc_check_header(png_const_structrp png_ptr, png_colorspacerp colorspace,
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* application requirements; the spec provides no guidance, but it's pretty
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* weird if the profile is not scanner ('scnr'), monitor ('mntr'), printer
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* ('prtr') or 'spac' (for generic color spaces). Issue a warning in these
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* cases.
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* cases. Issue an error for device link or abstract profiles - these don't
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* contain the records necessary to transform the color-space to anything
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* other than the target device (and not even that for an abstract profile).
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* Profiles of these classes may not be embedded in images.
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*/
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temp = png_get_uint_32(profile+12); /* profile/device class */
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if (temp != 0x73636E72 /* 'scnr' */ && temp != 0x6D6E7472 /* 'mntr' */ &&
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temp != 0x70727472 /* 'prtr' */ && temp != 0x73706163 /* 'spac' */)
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(void)profile_error(png_ptr, NULL, name, temp, "unexpected class");
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{
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if (temp == 0x6C696E6B /* 'link' */ || temp == 0x61627374 /* 'abst' */)
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return profile_error(png_ptr, colorspace, name, temp,
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"invalid class");
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/* This can only be 0x6E6D636C: a 'nmcl' profile. This is a device
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* specific profile.
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*/
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else
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(void)profile_error(png_ptr, NULL, name, temp, "unexpected ICC class");
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}
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return 1;
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}
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@ -2166,10 +2176,14 @@ png_icc_set_gAMA_and_cHRM(png_const_structrp png_ptr,
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# endif
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/* 2) Attempt to extract the gAMA and cHRM information from non-sRGB
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* profiles.
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* profiles. Always set the rendering intent from the profile.
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*/
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{
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/* TODO: implement this! */
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/* TODO: implement this; at present it is possible to set a detectably
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* incorrect ICC profile which, unfortunately, is likely to cause external
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* color management software to crash (though the checks on the tag table
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* do actually eliminate the most dangerous errors).
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*/
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PNG_UNUSED(name) /* NYI */
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return 1;
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}
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@ -3240,8 +3254,7 @@ png_reciprocal2(png_fixed_point a, png_fixed_point b)
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* or 16-bit sample values.
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*
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* The tables used here were calculated using simple 'bc' programs, but C double
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* precision floating point arithmetic would work fine. The programs are given
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* at the head of each table.
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* precision floating point arithmetic would work fine.
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*
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* 8-bit log table
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* This is a table of -log(value/255)/log(2) for 'value' in the range 128 to
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@ -3295,18 +3308,18 @@ png_8bit_l2[128] =
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#endif
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};
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PNG_STATIC png_int_32
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static png_int_32
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png_log8bit(unsigned int x)
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{
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unsigned int lg2 = 0;
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/* Each time 'x' is multiplied by 2, 1 must be subtracted off the final log,
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* because the log is actually negate that means adding 1. The final
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* returned value thus has the range 0 (for 255 input) to 7.994 (for 1
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* input), return 7.99998 for the overflow (log 0) case - so the result is
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* input), return -1 for the overflow (log 0) case, - so the result is
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* always at most 19 bits.
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*/
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if ((x &= 0xff) == 0)
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return 0xffffffff;
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return -1;
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if ((x & 0xf0) == 0)
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lg2 = 4, x <<= 4;
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@ -3351,14 +3364,14 @@ png_log8bit(unsigned int x)
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* Zero (257): 0
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* End (258): 23499
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*/
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PNG_STATIC png_int_32
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static png_int_32
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png_log16bit(png_uint_32 x)
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{
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unsigned int lg2 = 0;
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/* As above, but now the input has 16 bits. */
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if ((x &= 0xffff) == 0)
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return 0xffffffff;
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return -1;
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if ((x & 0xff00) == 0)
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lg2 = 8, x <<= 8;
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@ -3442,7 +3455,7 @@ for (i=11;i>=0;--i){ print i, " ", (1 - e(-(2^i)/65536*l(2))) * 2^(32-i), "\n"}
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0 45425.85339951654943850496
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#endif
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PNG_STATIC png_uint_32
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static png_uint_32
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png_exp(png_fixed_point x)
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{
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if (x > 0 && x <= 0xfffff) /* Else overflow or zero (underflow) */
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@ -3490,7 +3503,7 @@ png_exp(png_fixed_point x)
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return 0;
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}
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PNG_STATIC png_byte
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static png_byte
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png_exp8bit(png_fixed_point lg2)
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{
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/* Get a 32-bit value: */
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@ -3504,7 +3517,7 @@ png_exp8bit(png_fixed_point lg2)
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return (png_byte)((x + 0x7fffffU) >> 24);
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}
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PNG_STATIC png_uint_16
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static png_uint_16
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png_exp16bit(png_fixed_point lg2)
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{
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/* Get a 32-bit value: */
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@ -1471,7 +1471,9 @@ PNG_INTERNAL_FUNCTION(int,png_icc_set_gAMA_and_cHRM,(
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PNG_EMPTY);
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/* 'adler' is the Adler32 checksum of the uncompressed profile data. It may
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* be zero to indicate that it is not available. It is used, if provided,
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* as a fast check on the profile when checking to see if it is sRGB.
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* as a fast check on the profile when checking to see if it is sRGB. The
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* result is false only if an error is detected in the profile; the routine
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* may return true without actually setting cHRM and gAMA values.
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*/
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#endif /* iCCP */
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