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[devel] Fixed some spelling and indentation.

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This commit is contained in:
Glenn Randers-Pehrson 2010-07-29 21:49:38 -05:00
parent b9109e8254
commit 233357ef0e
5 changed files with 71 additions and 29 deletions
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84
png.c
View File

@ -1342,7 +1342,7 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
} }
/* Here on buffer too small. */ /* Here on buffer too small. */
png_error(png_ptr, "ASCII convertion buffer too small"); png_error(png_ptr, "ASCII conversion buffer too small");
} }
# endif /* FLOATING_POINT */ # endif /* FLOATING_POINT */
@ -1401,9 +1401,21 @@ png_muldiv(png_fixed_point_p res, png_fixed_point a, png_int_32 times,
#else #else
int negative = 0; int negative = 0;
png_uint_32 A, T, D; png_uint_32 A, T, D;
if (a < 0) negative = 1, A = -a; else A = a;
if (times < 0) negative = !negative, T = -times; else T = times; if (a < 0)
if (div < 0) negative = !negative, D = -div; else D = div; negative = 1, A = -a;
else
A = a;
if (times < 0)
negative = !negative, T = -times;
else
T = times;
if (div < 0)
negative = !negative, D = -div;
else
D = div;
/* Following can't overflow because the arguments only /* Following can't overflow because the arguments only
* have 31 bits each, however the result may be 32 bits. * have 31 bits each, however the result may be 32 bits.
@ -1432,6 +1444,7 @@ png_muldiv(png_fixed_point_p res, png_fixed_point a, png_int_32 times,
while (--bitshift >= 0) while (--bitshift >= 0)
{ {
png_uint_32 d32, d00; png_uint_32 d32, d00;
if (bitshift > 0) if (bitshift > 0)
d32 = D >> (32-bitshift), d00 = D << bitshift; d32 = D >> (32-bitshift), d00 = D << bitshift;
else else
@ -1442,7 +1455,8 @@ png_muldiv(png_fixed_point_p res, png_fixed_point a, png_int_32 times,
if (s00 < d00) --s32; /* carry */ if (s00 < d00) --s32; /* carry */
s32 -= d32, s00 -= d00, result += 1<<bitshift; s32 -= d32, s00 -= d00, result += 1<<bitshift;
} }
else if (s32 == d32 && s00 >= d00) else
if (s32 == d32 && s00 >= d00)
s32 = 0, s00 -= d00, result += 1<<bitshift; s32 = 0, s00 -= d00, result += 1<<bitshift;
} }
@ -1638,7 +1652,7 @@ png_8bit_l2[128] =
24347096U, 0U 24347096U, 0U
#if 0 #if 0
/* The following are the values for 16 bit tables - these work fine for the 8 /* The following are the values for 16 bit tables - these work fine for the 8
* bit convertions but produce very slightly larger errors in the 16 bit log * bit conversions but produce very slightly larger errors in the 16 bit log
* (about 1.2 as opposed to 0.7 absolute error in the final value). To use * (about 1.2 as opposed to 0.7 absolute error in the final value). To use
* these all the shifts below must be adjusted appropriately. * these all the shifts below must be adjusted appropriately.
*/ */
@ -1667,10 +1681,18 @@ png_log8bit(unsigned x)
* input), return 7.99998 for the overflow (log 0) case - so the result is * input), return 7.99998 for the overflow (log 0) case - so the result is
* always at most 19 bits. * always at most 19 bits.
*/ */
if ((x &= 0xff) == 0) return 0xffffffff; if ((x &= 0xff) == 0)
if ((x & 0xf0) == 0) log = 4, x <<= 4; return 0xffffffff;
if ((x & 0xc0) == 0) log += 2, x <<= 2;
if ((x & 0x80) == 0) log += 1, x <<= 1; if ((x & 0xf0) == 0)
log = 4, x <<= 4;
if ((x & 0xc0) == 0)
log += 2, x <<= 2;
if ((x & 0x80) == 0)
log += 1, x <<= 1;
return (log << 16) + ((png_8bit_l2[x-128]+32768)>>16); return (log << 16) + ((png_8bit_l2[x-128]+32768)>>16);
} }
@ -1710,11 +1732,20 @@ png_log16bit(png_uint_32 x)
unsigned log = 0; unsigned log = 0;
/* As above, but now the input has 16 bits. */ /* As above, but now the input has 16 bits. */
if ((x &= 0xffff) == 0) return 0xffffffff; if ((x &= 0xffff) == 0)
if ((x & 0xff00) == 0) log = 8, x <<= 8; return 0xffffffff;
if ((x & 0xf000) == 0) log += 4, x <<= 4;
if ((x & 0xc000) == 0) log += 2, x <<= 2; if ((x & 0xff00) == 0)
if ((x & 0x8000) == 0) log += 1, x <<= 1; log = 8, x <<= 8;
if ((x & 0xf000) == 0)
log += 4, x <<= 4;
if ((x & 0xc000) == 0)
log += 2, x <<= 2;
if ((x & 0x8000) == 0)
log += 1, x <<= 1;
/* Calculate the base logarithm from the top 8 bits as a 28 bit fractional /* Calculate the base logarithm from the top 8 bits as a 28 bit fractional
* value. * value.
@ -1800,12 +1831,23 @@ png_exp(png_uint_32 x)
* converge on 45426 and this is used to allow linear interpolation of the * converge on 45426 and this is used to allow linear interpolation of the
* low bits. * low bits.
*/ */
if (x & 0x800) e -= (((e >> 16) * 44938U) + 16U) >> 5; if (x & 0x800)
if (x & 0x400) e -= (((e >> 16) * 45181U) + 32U) >> 6; e -= (((e >> 16) * 44938U) + 16U) >> 5;
if (x & 0x200) e -= (((e >> 16) * 45303U) + 64U) >> 7;
if (x & 0x100) e -= (((e >> 16) * 45365U) + 128U) >> 8; if (x & 0x400)
if (x & 0x080) e -= (((e >> 16) * 45395U) + 256U) >> 9; e -= (((e >> 16) * 45181U) + 32U) >> 6;
if (x & 0x040) e -= (((e >> 16) * 45410U) + 512U) >> 10;
if (x & 0x200)
e -= (((e >> 16) * 45303U) + 64U) >> 7;
if (x & 0x100)
e -= (((e >> 16) * 45365U) + 128U) >> 8;
if (x & 0x080)
e -= (((e >> 16) * 45395U) + 256U) >> 9;
if (x & 0x040)
e -= (((e >> 16) * 45410U) + 512U) >> 10;
/* And handle the low 6 bits in a single block. */ /* And handle the low 6 bits in a single block. */
e -= (((e >> 16) * 355U * (x & 0x3fU)) + 256U) >> 9; e -= (((e >> 16) * 355U * (x & 0x3fU)) + 256U) >> 9;

2
pngget.c
View File

@ -295,7 +295,7 @@ static png_uint_32
ppi_from_ppm(png_uint_32 ppm) ppi_from_ppm(png_uint_32 ppm)
{ {
#if 0 #if 0
/* The convertion is *(2.54/100), in binary (32 digits): /* The conversion is *(2.54/100), in binary (32 digits):
* .00000110100000001001110101001001 * .00000110100000001001110101001001
*/ */
png_uint_32 t1001, t1101; png_uint_32 t1001, t1101;

8
pngpriv.h
View File

@ -116,11 +116,11 @@
*/ */
#if defined(PNG_FLOATING_POINT_SUPPORTED) ||\ #if defined(PNG_FLOATING_POINT_SUPPORTED) ||\
defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)
/* pngarith.c requires the following ANSI-C constants if the convertion of /* png.c requires the following ANSI-C constants if the conversion of
* floating point to ASCII is implemented therein: * floating point to ASCII is implemented therein:
* *
* DBL_DIG Maximum number of decimal digits (can be set to any constant) * DBL_DIG Maximum number of decimal digits (can be set to any constant)
* DBL_MIN Smalles normalized fp number (can be set to an arbitrary value) * DBL_MIN Smallest normalized fp number (can be set to an arbitrary value)
* DBL_MAX Maximum floating point number (can be set to an arbitrary value) * DBL_MAX Maximum floating point number (can be set to an arbitrary value)
*/ */
# include <float.h> # include <float.h>
@ -366,7 +366,7 @@
* when it is supposedly disabled.) * when it is supposedly disabled.)
*/ */
#ifdef PNG_FLOATING_POINT_SUPPORTED #ifdef PNG_FLOATING_POINT_SUPPORTED
/* The floating point convertion can't overflow, though it can and /* The floating point conversion can't overflow, though it can and
* does lose accuracy relative to the original fixed point value. * does lose accuracy relative to the original fixed point value.
* In practice this doesn't matter because png_fixed_point only * In practice this doesn't matter because png_fixed_point only
* stores numbers with very low precision. The png_ptr and s * stores numbers with very low precision. The png_ptr and s
@ -375,7 +375,7 @@
*/ */
#define png_float(png_ptr, fixed, s) (.00001 * (fixed)) #define png_float(png_ptr, fixed, s) (.00001 * (fixed))
/* The fixed point convertion performs range checking and evaluates /* The fixed point conversion performs range checking and evaluates
* its argument multiple times, so must be used with care. The * its argument multiple times, so must be used with care. The
* range checking uses the PNG specification values for a signed * range checking uses the PNG specification values for a signed
* 32 bit fixed point value except that the values are deliberately * 32 bit fixed point value except that the values are deliberately

2
pngrutil.c
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@ -71,7 +71,7 @@ png_get_uint_32)(png_bytep buf)
/* Grab a signed 32-bit integer from a buffer in big-endian format. The /* Grab a signed 32-bit integer from a buffer in big-endian format. The
* data is stored in the PNG file in two's complement format and there * data is stored in the PNG file in two's complement format and there
* is no guarantee that a 'png_int_32' is exactly 32 bits, therefore * is no guarantee that a 'png_int_32' is exactly 32 bits, therefore
* the following code does a two's complement to native convertion. * the following code does a two's complement to native conversion.
*/ */
png_int_32 (PNGAPI png_int_32 (PNGAPI
png_get_int_32)(png_bytep buf) png_get_int_32)(png_bytep buf)

2
pngvalid.c
View File

@ -1876,7 +1876,7 @@ static void perform_gamma_strip16_tests(png_modifier *pm, int speed)
* used by the library - otherwise we will get spurious errors from the * used by the library - otherwise we will get spurious errors from the
* internal sbit style approximation. * internal sbit style approximation.
* *
* The threshold test is here because otherwise the 16 to 8 convertion will * The threshold test is here because otherwise the 16 to 8 conversion will
* proceed *without* gamma correction, and the tests above will fail (but not * proceed *without* gamma correction, and the tests above will fail (but not
* by much) - this could be fixed, it only appears with the -g option. * by much) - this could be fixed, it only appears with the -g option.
*/ */