diff options
Diffstat (limited to 'Build/source/libs/libpng/libpng-1.6.2/contrib/libtests/tarith.c')
-rw-r--r-- | Build/source/libs/libpng/libpng-1.6.2/contrib/libtests/tarith.c | 999 |
1 files changed, 0 insertions, 999 deletions
diff --git a/Build/source/libs/libpng/libpng-1.6.2/contrib/libtests/tarith.c b/Build/source/libs/libpng/libpng-1.6.2/contrib/libtests/tarith.c deleted file mode 100644 index cdb00dbf7e7..00000000000 --- a/Build/source/libs/libpng/libpng-1.6.2/contrib/libtests/tarith.c +++ /dev/null @@ -1,999 +0,0 @@ - -/* tarith.c - * - * Copyright (c) 2011-2013 John Cunningham Bowler - * - * Last changed in libpng 1.6.0 [February 14, 2013] - * - * This code is released under the libpng license. - * For conditions of distribution and use, see the disclaimer - * and license in png.h - * - * Test internal arithmetic functions of libpng. - * - * This code must be linked against a math library (-lm), but does not require - * libpng or zlib to work. Because it includes the complete source of 'png.c' - * it tests the code with whatever compiler options are used to build it. - * Changing these options can substantially change the errors in the - * calculations that the compiler chooses! - */ -#define _POSIX_SOURCE 1 -#define _ISOC99_SOURCE 1 - -/* Obtain a copy of the code to be tested (plus other things), disabling - * stuff that is not required. - */ -#include <math.h> -#include <stdlib.h> -#include <ctype.h> -#include <string.h> -#include <assert.h> - -#include "../../pngpriv.h" - -#define png_error png_warning - -void png_warning(png_const_structrp png_ptr, png_const_charp msg) -{ - fprintf(stderr, "validation: %s\n", msg); -} - -#define png_fixed_error png_fixed_warning - -void png_fixed_warning(png_const_structrp png_ptr, png_const_charp msg) -{ - fprintf(stderr, "overflow in: %s\n", msg); -} - -#define png_set_error_fn(pp, ep, efp, wfp) ((void)0) -#define png_malloc(pp, s) malloc(s) -#define png_malloc_warn(pp, s) malloc(s) -#define png_malloc_base(pp, s) malloc(s) -#define png_calloc(pp, s) calloc(1, (s)) -#define png_free(pp, s) free(s) - -#define png_safecat(b, sb, pos, str) (pos) -#define png_format_number(start, end, format, number) (start) - -#define crc32(crc, pp, s) (crc) -#define inflateReset(zs) Z_OK - -#define png_create_struct(type) (0) -#define png_destroy_struct(pp) ((void)0) -#define png_create_struct_2(type, m, mm) (0) -#define png_destroy_struct_2(pp, f, mm) ((void)0) - -#undef PNG_SIMPLIFIED_READ_SUPPORTED -#undef PNG_SIMPLIFIED_WRITE_SUPPORTED -#undef PNG_USER_MEM_SUPPORTED - -#include "../../png.c" - -/* Validate ASCII to fp routines. */ -static int verbose = 0; - -int validation_ascii_to_fp(int count, int argc, char **argv) -{ - int showall = 0; - double max_error=2; /* As a percentage error-in-last-digit/.5 */ - double max_error_abs=17; /* Used when precision is DBL_DIG */ - double max = 0; - double max_abs = 0; - double test = 0; /* Important to test this. */ - int precision = 5; - int nonfinite = 0; - int finite = 0; - int ok = 0; - int failcount = 0; - int minorarith = 0; - - while (--argc > 0) - if (strcmp(*++argv, "-a") == 0) - showall = 1; - else if (strcmp(*argv, "-e") == 0 && argc > 0) - { - --argc; - max_error = atof(*++argv); - } - else if (strcmp(*argv, "-E") == 0 && argc > 0) - { - --argc; - max_error_abs = atof(*++argv); - } - else - { - fprintf(stderr, "unknown argument %s\n", *argv); - return 1; - } - - do - { - png_size_t index; - int state, failed = 0; - char buffer[64]; - - if (isfinite(test)) - ++finite; - else - ++nonfinite; - - if (verbose) - fprintf(stderr, "%.*g %d\n", DBL_DIG, test, precision); - - /* Check for overflow in the buffer by setting a marker. */ - memset(buffer, 71, sizeof buffer); - - png_ascii_from_fp(0, buffer, precision+10, test, precision); - - /* Allow for a three digit exponent, this stuff will fail if - * the exponent is bigger than this! - */ - if (buffer[precision+7] != 71) - { - fprintf(stderr, "%g[%d] -> '%s'[%lu] buffer overflow\n", test, - precision, buffer, (unsigned long)strlen(buffer)); - failed = 1; - } - - /* Following are used for the number parser below and must be - * initialized to zero. - */ - state = 0; - index = 0; - if (!isfinite(test)) - { - /* Expect 'inf' */ - if (test >= 0 && strcmp(buffer, "inf") || - test < 0 && strcmp(buffer, "-inf")) - { - fprintf(stderr, "%g[%d] -> '%s' but expected 'inf'\n", test, - precision, buffer); - failed = 1; - } - } - else if (!png_check_fp_number(buffer, precision+10, &state, &index) || - buffer[index] != 0) - { - fprintf(stderr, "%g[%d] -> '%s' but has bad format ('%c')\n", test, - precision, buffer, buffer[index]); - failed = 1; - } - else if (PNG_FP_IS_NEGATIVE(state) && !(test < 0)) - { - fprintf(stderr, "%g[%d] -> '%s' but negative value not so reported\n", - test, precision, buffer); - failed = 1; - assert(!PNG_FP_IS_ZERO(state)); - assert(!PNG_FP_IS_POSITIVE(state)); - } - else if (PNG_FP_IS_ZERO(state) && !(test == 0)) - { - fprintf(stderr, "%g[%d] -> '%s' but zero value not so reported\n", - test, precision, buffer); - failed = 1; - assert(!PNG_FP_IS_NEGATIVE(state)); - assert(!PNG_FP_IS_POSITIVE(state)); - } - else if (PNG_FP_IS_POSITIVE(state) && !(test > 0)) - { - fprintf(stderr, "%g[%d] -> '%s' but postive value not so reported\n", - test, precision, buffer); - failed = 1; - assert(!PNG_FP_IS_NEGATIVE(state)); - assert(!PNG_FP_IS_ZERO(state)); - } - else - { - /* Check the result against the original. */ - double out = atof(buffer); - double change = fabs((out - test)/test); - double allow = .5/pow(10, - (precision >= DBL_DIG) ? DBL_DIG-1 : precision-1); - - /* NOTE: if you hit this error case are you compiling with gcc - * and -O0? Try -O2 - the errors can accumulate if the FP - * code above is not optimized and may drift outside the .5 in - * DBL_DIG allowed. In any case a small number of errors may - * occur (very small ones - 1 or 2%) because of rounding in the - * calculations, either in the conversion API or in atof. - */ - if (change >= allow && (isfinite(out) || - fabs(test/DBL_MAX) <= 1-allow)) - { - double percent = (precision >= DBL_DIG) ? max_error_abs : max_error; - double allowp = (change-allow)*100/allow; - - if (precision >= DBL_DIG) - { - if (max_abs < allowp) max_abs = allowp; - } - - else - { - if (max < allowp) max = allowp; - } - - if (showall || allowp >= percent) - { - fprintf(stderr, - "%.*g[%d] -> '%s' -> %.*g number changed (%g > %g (%d%%))\n", - DBL_DIG, test, precision, buffer, DBL_DIG, out, change, allow, - (int)round(allowp)); - failed = 1; - } - else - ++minorarith; - } - } - - if (failed) - ++failcount; - else - ++ok; - -skip: - /* Generate a new number and precision. */ - precision = rand(); - if (precision & 1) test = -test; - precision >>= 1; - - /* Generate random numbers. */ - if (test == 0 || !isfinite(test)) - test = precision+1; - else - { - /* Derive the exponent from the previous rand() value. */ - int exponent = precision % (DBL_MAX_EXP - DBL_MIN_EXP) + DBL_MIN_EXP; - int tmp; - test = frexp(test * rand(), &tmp); - test = ldexp(test, exponent); - precision >>= 8; /* arbitrary */ - } - - /* This limits the precision to 32 digits, enough for standard - * IEEE implementations which have at most 15 digits. - */ - precision = (precision & 0x1f) + 1; - } - while (--count); - - printf("Tested %d finite values, %d non-finite, %d OK (%d failed) %d minor " - "arithmetic errors\n", finite, nonfinite, ok, failcount, minorarith); - printf(" Error with >=%d digit precision %.2f%%\n", DBL_DIG, max_abs); - printf(" Error with < %d digit precision %.2f%%\n", DBL_DIG, max); - - return 0; -} - -/* Observe that valid FP numbers have the forms listed in the PNG extensions - * specification: - * - * [+,-]{integer,integer.fraction,.fraction}[{e,E}[+,-]integer] - * - * Test each of these in turn, including invalid cases. - */ -typedef enum checkfp_state -{ - start, fraction, exponent, states -} checkfp_state; - -/* The characters (other than digits) that characterize the states: */ -static const char none[] = ""; -static const char hexdigits[16] = "0123456789ABCDEF"; - -static const struct -{ - const char *start; /* Characters valid at the start */ - const char *end; /* Valid characters that end the state */ - const char *tests; /* Characters to test after 2 digits seen */ -} -state_characters[states] = -{ - /* start: */ { "+-.", ".eE", "+-.e*0369" }, - /* fraction: */ { none, "eE", "+-.E#0147" }, - /* exponent: */ { "+-", none, "+-.eE^0258" } -}; - -typedef struct -{ - char number[1024]; /* Buffer for number being tested */ - int limit; /* Command line limit */ - int verbose; /* Shadows global variable */ - int ctimes; /* Number of numbers tested */ - int cmillions; /* Count of millions of numbers */ - int cinvalid; /* Invalid strings checked */ - int cnoaccept; /* Characters not accepted */ -} -checkfp_command; - -typedef struct -{ - int cnumber; /* Index into number string */ - checkfp_state check_state; /* Current number state */ - int at_start; /* At start (first character) of state */ - int cdigits_in_state; /* Digits seen in that state */ - int limit; /* Limit on same for checking all chars */ - int state; /* Current parser state */ - int is_negative; /* Number is negative */ - int is_zero; /* Number is (still) zero */ - int number_was_valid; /* Previous character validity */ -} -checkfp_control; - -static int check_all_characters(checkfp_command *co, checkfp_control c); - -static int check_some_characters(checkfp_command *co, checkfp_control c, - const char *tests); - -static int check_one_character(checkfp_command *co, checkfp_control c, int ch) -{ - /* Test this character (ch) to ensure the parser does the correct thing. - */ - png_size_t index = 0; - const char test = (char)ch; - const int number_is_valid = png_check_fp_number(&test, 1, &c.state, &index); - const int character_accepted = (index == 1); - - if (c.check_state != exponent && isdigit(ch) && ch != '0') - c.is_zero = 0; - - if (c.check_state == start && c.at_start && ch == '-') - c.is_negative = 1; - - if (isprint(ch)) - co->number[c.cnumber++] = (char)ch; - else - { - co->number[c.cnumber++] = '<'; - co->number[c.cnumber++] = hexdigits[(ch >> 4) & 0xf]; - co->number[c.cnumber++] = hexdigits[ch & 0xf]; - co->number[c.cnumber++] = '>'; - } - co->number[c.cnumber] = 0; - - if (co->verbose > 1) - fprintf(stderr, "%s\n", co->number); - - if (++(co->ctimes) == 1000000) - { - if (co->verbose == 1) - fputc('.', stderr); - co->ctimes = 0; - ++(co->cmillions); - } - - if (!number_is_valid) - ++(co->cinvalid); - - if (!character_accepted) - ++(co->cnoaccept); - - /* This should never fail (it's a serious bug if it does): */ - if (index != 0 && index != 1) - { - fprintf(stderr, "%s: read beyond end of string (%lu)\n", co->number, - (unsigned long)index); - return 0; - } - - /* Validate the new state, note that the PNG_FP_IS_ macros all return - * false unless the number is valid. - */ - if (PNG_FP_IS_NEGATIVE(c.state) != - (number_is_valid && !c.is_zero && c.is_negative)) - { - fprintf(stderr, "%s: negative when it is not\n", co->number); - return 0; - } - - if (PNG_FP_IS_ZERO(c.state) != (number_is_valid && c.is_zero)) - { - fprintf(stderr, "%s: zero when it is not\n", co->number); - return 0; - } - - if (PNG_FP_IS_POSITIVE(c.state) != - (number_is_valid && !c.is_zero && !c.is_negative)) - { - fprintf(stderr, "%s: positive when it is not\n", co->number); - return 0; - } - - /* Testing a digit */ - if (isdigit(ch)) - { - if (!character_accepted) - { - fprintf(stderr, "%s: digit '%c' not accepted\n", co->number, ch); - return 0; - } - - if (!number_is_valid) - { - fprintf(stderr, "%s: saw a digit (%c) but number not valid\n", - co->number, ch); - return 0; - } - - ++c.cdigits_in_state; - c.at_start = 0; - c.number_was_valid = 1; - - /* Continue testing characters in this state. Either test all of - * them or, if we have already seen one digit in this state, just test a - * limited set. - */ - if (c.cdigits_in_state < 1) - return check_all_characters(co, c); - - else - return check_some_characters(co, c, - state_characters[c.check_state].tests); - } - - /* A non-digit; is it allowed here? */ - else if (((ch == '+' || ch == '-') && c.check_state != fraction && - c.at_start) || - (ch == '.' && c.check_state == start) || - ((ch == 'e' || ch == 'E') && c.number_was_valid && - c.check_state != exponent)) - { - if (!character_accepted) - { - fprintf(stderr, "%s: character '%c' not accepted\n", co->number, ch); - return 0; - } - - /* The number remains valid after start of fraction but nowhere else. */ - if (number_is_valid && (c.check_state != start || ch != '.')) - { - fprintf(stderr, "%s: saw a non-digit (%c) but number valid\n", - co->number, ch); - return 0; - } - - c.number_was_valid = number_is_valid; - - /* Check for a state change. When changing to 'fraction' if the number - * is valid at this point set the at_start to false to allow an exponent - * 'e' to come next. - */ - if (c.check_state == start && ch == '.') - { - c.check_state = fraction; - c.at_start = !number_is_valid; - c.cdigits_in_state = 0; - c.limit = co->limit; - return check_all_characters(co, c); - } - - else if (c.check_state < exponent && (ch == 'e' || ch == 'E')) - { - c.check_state = exponent; - c.at_start = 1; - c.cdigits_in_state = 0; - c.limit = co->limit; - return check_all_characters(co, c); - } - - /* Else it was a sign, and the state doesn't change. */ - else - { - if (ch != '-' && ch != '+') - { - fprintf(stderr, "checkfp: internal error (1)\n"); - return 0; - } - - c.at_start = 0; - return check_all_characters(co, c); - } - } - - /* Testing an invalid character */ - else - { - if (character_accepted) - { - fprintf(stderr, "%s: character '%c' [0x%.2x] accepted\n", co->number, - ch, ch); - return 0; - } - - if (number_is_valid != c.number_was_valid) - { - fprintf(stderr, - "%s: character '%c' [0x%.2x] changed number validity\n", co->number, - ch, ch); - return 0; - } - - /* Do nothing - the parser has stuck; return success and keep going with - * the next character. - */ - } - - /* Successful return (the caller will try the next character.) */ - return 1; -} - -static int check_all_characters(checkfp_command *co, checkfp_control c) -{ - int ch; - - if (c.cnumber+4 < sizeof co->number) for (ch=0; ch<256; ++ch) - { - if (!check_one_character(co, c, ch)) - return 0; - } - - return 1; -} - -static int check_some_characters(checkfp_command *co, checkfp_control c, - const char *tests) -{ - int i; - - --(c.limit); - - if (c.cnumber+4 < sizeof co->number && c.limit >= 0) - { - if (c.limit > 0) for (i=0; tests[i]; ++i) - { - if (!check_one_character(co, c, tests[i])) - return 0; - } - - /* At the end check all the characters. */ - else - return check_all_characters(co, c); - } - - return 1; -} - -int validation_checkfp(int count, int argc, char **argv) -{ - int result; - checkfp_command command; - checkfp_control control; - - command.number[0] = 0; - command.limit = 3; - command.verbose = verbose; - command.ctimes = 0; - command.cmillions = 0; - command.cinvalid = 0; - command.cnoaccept = 0; - - while (--argc > 0) - { - ++argv; - if (argc > 1 && strcmp(*argv, "-l") == 0) - { - --argc; - command.limit = atoi(*++argv); - } - - else - { - fprintf(stderr, "unknown argument %s\n", *argv); - return 1; - } - } - - control.cnumber = 0; - control.check_state = start; - control.at_start = 1; - control.cdigits_in_state = 0; - control.limit = command.limit; - control.state = 0; - control.is_negative = 0; - control.is_zero = 1; - control.number_was_valid = 0; - - result = check_all_characters(&command, control); - - printf("checkfp: %s: checked %d,%.3d,%.3d,%.3d strings (%d invalid)\n", - result ? "pass" : "FAIL", command.cmillions / 1000, - command.cmillions % 1000, command.ctimes / 1000, command.ctimes % 1000, - command.cinvalid); - - return result; -} - -int validation_muldiv(int count, int argc, char **argv) -{ - int tested = 0; - int overflow = 0; - int error = 0; - int error64 = 0; - int passed = 0; - int randbits = 0; - png_uint_32 randbuffer; - png_fixed_point a; - png_int_32 times, div; - - while (--argc > 0) - { - fprintf(stderr, "unknown argument %s\n", *++argv); - return 1; - } - - /* Find out about the random number generator. */ - randbuffer = RAND_MAX; - while (randbuffer != 0) ++randbits, randbuffer >>= 1; - printf("Using random number generator that makes %d bits\n", randbits); - for (div=0; div<32; div += randbits) - randbuffer = (randbuffer << randbits) ^ rand(); - - a = 0; - times = div = 0; - do - { - png_fixed_point result; - /* NOTE: your mileage may vary, a type is required below that can - * hold 64 bits or more, if floating point is used a 64 bit or - * better mantissa is required. - */ - long long int fp, fpround; - unsigned long hi, lo; - int ok; - - /* Check the values, png_64bit_product can only handle positive - * numbers, so correct for that here. - */ - { - long u1, u2; - int n = 0; - if (a < 0) u1 = -a, n = 1; else u1 = a; - if (times < 0) u2 = -times, n = !n; else u2 = times; - png_64bit_product(u1, u2, &hi, &lo); - if (n) - { - /* -x = ~x+1 */ - lo = ((~lo) + 1) & 0xffffffff; - hi = ~hi; - if (lo == 0) ++hi; - } - } - - fp = a; - fp *= times; - if ((fp & 0xffffffff) != lo || ((fp >> 32) & 0xffffffff) != hi) - { - fprintf(stderr, "png_64bit_product %d * %d -> %lx|%.8lx not %llx\n", - a, times, hi, lo, fp); - ++error64; - } - - if (div != 0) - { - /* Round - this is C round to zero. */ - if ((fp < 0) != (div < 0)) - fp -= div/2; - else - fp += div/2; - - fp /= div; - fpround = fp; - /* Assume 2's complement here: */ - ok = fpround <= PNG_UINT_31_MAX && - fpround >= -1-(long long int)PNG_UINT_31_MAX; - if (!ok) ++overflow; - } - else - ok = 0, ++overflow, fpround = fp/*misleading*/; - - if (verbose) - fprintf(stderr, "TEST %d * %d / %d -> %lld (%s)\n", a, times, div, - fp, ok ? "ok" : "overflow"); - - ++tested; - if (png_muldiv(&result, a, times, div) != ok) - { - ++error; - if (ok) - fprintf(stderr, "%d * %d / %d -> overflow (expected %lld)\n", a, - times, div, fp); - else - fprintf(stderr, "%d * %d / %d -> %d (expected overflow %lld)\n", a, - times, div, result, fp); - } - else if (ok && result != fpround) - { - ++error; - fprintf(stderr, "%d * %d / %d -> %d not %lld\n", a, times, div, result, - fp); - } - else - ++passed; - - /* Generate three new values, this uses rand() and rand() only returns - * up to RAND_MAX. - */ - /* CRUDE */ - a += times; - times += div; - div = randbuffer; - randbuffer = (randbuffer << randbits) ^ rand(); - } - while (--count > 0); - - printf("%d tests including %d overflows, %d passed, %d failed (%d 64 bit " - "errors)\n", tested, overflow, passed, error, error64); - return 0; -} - -/* When FP is on this just becomes a speed test - compile without FP to get real - * validation. - */ -#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED -#define LN2 .000010576586617430806112933839 /* log(2)/65536 */ -#define L2INV 94548.46219969910586572651 /* 65536/log(2) */ - -/* For speed testing, need the internal functions too: */ -static png_uint_32 png_log8bit(unsigned x) -{ - if (x > 0) - return (png_uint_32)floor(.5-log(x/255.)*L2INV); - - return 0xffffffff; -} - -static png_uint_32 png_log16bit(png_uint_32 x) -{ - if (x > 0) - return (png_uint_32)floor(.5-log(x/65535.)*L2INV); - - return 0xffffffff; -} - -static png_uint_32 png_exp(png_uint_32 x) -{ - return (png_uint_32)floor(.5 + exp(x * -LN2) * 0xffffffffU); -} - -static png_byte png_exp8bit(png_uint_32 log) -{ - return (png_byte)floor(.5 + exp(log * -LN2) * 255); -} - -static png_uint_16 png_exp16bit(png_uint_32 log) -{ - return (png_uint_16)floor(.5 + exp(log * -LN2) * 65535); -} -#endif /* FLOATING_ARITHMETIC */ - -int validation_gamma(int argc, char **argv) -{ - double gamma[9] = { 2.2, 1.8, 1.52, 1.45, 1., 1/1.45, 1/1.52, 1/1.8, 1/2.2 }; - double maxerr; - int i, silent=0, onlygamma=0; - - /* Silence the output with -s, just test the gamma functions with -g: */ - while (--argc > 0) - if (strcmp(*++argv, "-s") == 0) - silent = 1; - else if (strcmp(*argv, "-g") == 0) - onlygamma = 1; - else - { - fprintf(stderr, "unknown argument %s\n", *argv); - return 1; - } - - if (!onlygamma) - { - /* First validate the log functions: */ - maxerr = 0; - for (i=0; i<256; ++i) - { - double correct = -log(i/255.)/log(2.)*65536; - double error = png_log8bit(i) - correct; - - if (i != 0 && fabs(error) > maxerr) - maxerr = fabs(error); - - if (i == 0 && png_log8bit(i) != 0xffffffff || - i != 0 && png_log8bit(i) != floor(correct+.5)) - { - fprintf(stderr, "8 bit log error: %d: got %u, expected %f\n", - i, png_log8bit(i), correct); - } - } - - if (!silent) - printf("maximum 8 bit log error = %f\n", maxerr); - - maxerr = 0; - for (i=0; i<65536; ++i) - { - double correct = -log(i/65535.)/log(2.)*65536; - double error = png_log16bit(i) - correct; - - if (i != 0 && fabs(error) > maxerr) - maxerr = fabs(error); - - if (i == 0 && png_log16bit(i) != 0xffffffff || - i != 0 && png_log16bit(i) != floor(correct+.5)) - { - if (error > .68) /* By experiment error is less than .68 */ - { - fprintf(stderr, "16 bit log error: %d: got %u, expected %f" - " error: %f\n", i, png_log16bit(i), correct, error); - } - } - } - - if (!silent) - printf("maximum 16 bit log error = %f\n", maxerr); - - /* Now exponentiations. */ - maxerr = 0; - for (i=0; i<=0xfffff; ++i) - { - double correct = exp(-i/65536. * log(2.)) * (65536. * 65536); - double error = png_exp(i) - correct; - - if (fabs(error) > maxerr) - maxerr = fabs(error); - if (fabs(error) > 1883) /* By experiment. */ - { - fprintf(stderr, "32 bit exp error: %d: got %u, expected %f" - " error: %f\n", i, png_exp(i), correct, error); - } - } - - if (!silent) - printf("maximum 32 bit exp error = %f\n", maxerr); - - maxerr = 0; - for (i=0; i<=0xfffff; ++i) - { - double correct = exp(-i/65536. * log(2.)) * 255; - double error = png_exp8bit(i) - correct; - - if (fabs(error) > maxerr) - maxerr = fabs(error); - if (fabs(error) > .50002) /* By experiment */ - { - fprintf(stderr, "8 bit exp error: %d: got %u, expected %f" - " error: %f\n", i, png_exp8bit(i), correct, error); - } - } - - if (!silent) - printf("maximum 8 bit exp error = %f\n", maxerr); - - maxerr = 0; - for (i=0; i<=0xfffff; ++i) - { - double correct = exp(-i/65536. * log(2.)) * 65535; - double error = png_exp16bit(i) - correct; - - if (fabs(error) > maxerr) - maxerr = fabs(error); - if (fabs(error) > .524) /* By experiment */ - { - fprintf(stderr, "16 bit exp error: %d: got %u, expected %f" - " error: %f\n", i, png_exp16bit(i), correct, error); - } - } - - if (!silent) - printf("maximum 16 bit exp error = %f\n", maxerr); - } /* !onlygamma */ - - /* Test the overall gamma correction. */ - for (i=0; i<9; ++i) - { - unsigned j; - double g = gamma[i]; - png_fixed_point gfp = floor(g * PNG_FP_1 + .5); - - if (!silent) - printf("Test gamma %f\n", g); - - maxerr = 0; - for (j=0; j<256; ++j) - { - double correct = pow(j/255., g) * 255; - png_byte out = png_gamma_8bit_correct(j, gfp); - double error = out - correct; - - if (fabs(error) > maxerr) - maxerr = fabs(error); - if (out != floor(correct+.5)) - { - fprintf(stderr, "8bit %d ^ %f: got %d expected %f error %f\n", - j, g, out, correct, error); - } - } - - if (!silent) - printf("gamma %f: maximum 8 bit error %f\n", g, maxerr); - - maxerr = 0; - for (j=0; j<65536; ++j) - { - double correct = pow(j/65535., g) * 65535; - png_uint_16 out = png_gamma_16bit_correct(j, gfp); - double error = out - correct; - - if (fabs(error) > maxerr) - maxerr = fabs(error); - if (fabs(error) > 1.62) - { - fprintf(stderr, "16bit %d ^ %f: got %d expected %f error %f\n", - j, g, out, correct, error); - } - } - - if (!silent) - printf("gamma %f: maximum 16 bit error %f\n", g, maxerr); - } - - return 0; -} - -/**************************** VALIDATION TESTS ********************************/ -/* Various validation routines are included herein, they require some - * definition for png_warning and png_error, seetings of VALIDATION: - * - * 1: validates the ASCII to floating point conversions - * 2: validates png_muldiv - * 3: accuracy test of fixed point gamma tables - */ - -/* The following COUNT (10^8) takes about 1 hour on a 1GHz Pentium IV - * processor. - */ -#define COUNT 1000000000 - -int main(int argc, char **argv) -{ - int count = COUNT; - - while (argc > 1) - { - if (argc > 2 && strcmp(argv[1], "-c") == 0) - { - count = atoi(argv[2]); - argc -= 2; - argv += 2; - } - - else if (strcmp(argv[1], "-v") == 0) - { - ++verbose; - --argc; - ++argv; - } - - else - break; - } - - if (count > 0 && argc > 1) - { - if (strcmp(argv[1], "ascii") == 0) - return validation_ascii_to_fp(count, argc-1, argv+1); - else if (strcmp(argv[1], "checkfp") == 0) - return validation_checkfp(count, argc-1, argv+1); - else if (strcmp(argv[1], "muldiv") == 0) - return validation_muldiv(count, argc-1, argv+1); - else if (strcmp(argv[1], "gamma") == 0) - return validation_gamma(argc-1, argv+1); - } - - /* Bad argument: */ - fprintf(stderr, - "usage: tarith [-v] [-c count] {ascii,muldiv,gamma} [args]\n"); - fprintf(stderr, " arguments: ascii [-a (all results)] [-e error%%]\n"); - fprintf(stderr, " checkfp [-l max-number-chars]\n"); - fprintf(stderr, " muldiv\n"); - fprintf(stderr, " gamma -s (silent) -g (only gamma; no log)\n"); - return 1; -} |