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753 lines
24 KiB
753 lines
24 KiB
/* |
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* Copyright (c) 2002-2006 Michael Niedermayer <michaelni@gmx.at> |
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* Copyright (c) 2006 Oded Shimon <ods15@ods15.dyndns.org> |
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* |
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* This file is part of FFmpeg. |
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* |
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* FFmpeg is free software; you can redistribute it and/or |
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* modify it under the terms of the GNU Lesser General Public |
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* License as published by the Free Software Foundation; either |
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* version 2.1 of the License, or (at your option) any later version. |
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* |
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* FFmpeg is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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* Lesser General Public License for more details. |
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* |
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* You should have received a copy of the GNU Lesser General Public |
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* License along with FFmpeg; if not, write to the Free Software |
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
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*/ |
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|
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/** |
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* @file |
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* simple arithmetic expression evaluator. |
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* |
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* see http://joe.hotchkiss.com/programming/eval/eval.html |
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*/ |
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#include <float.h> |
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#include "attributes.h" |
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#include "avutil.h" |
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#include "common.h" |
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#include "eval.h" |
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#include "ffmath.h" |
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#include "internal.h" |
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#include "log.h" |
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#include "mathematics.h" |
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#include "time.h" |
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#include "avstring.h" |
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#include "timer.h" |
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#include "reverse.h" |
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typedef struct Parser { |
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const AVClass *class; |
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int stack_index; |
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char *s; |
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const double *const_values; |
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const char * const *const_names; // NULL terminated |
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double (* const *funcs1)(void *, double a); // NULL terminated |
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const char * const *func1_names; // NULL terminated |
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double (* const *funcs2)(void *, double a, double b); // NULL terminated |
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const char * const *func2_names; // NULL terminated |
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void *opaque; |
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int log_offset; |
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void *log_ctx; |
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#define VARS 10 |
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double *var; |
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} Parser; |
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static const AVClass eval_class = { "Eval", av_default_item_name, NULL, LIBAVUTIL_VERSION_INT, offsetof(Parser,log_offset), offsetof(Parser,log_ctx) }; |
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static const struct { |
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double bin_val; |
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double dec_val; |
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int8_t exp; |
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} si_prefixes['z' - 'E' + 1] = { |
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['y'-'E']= { 8.271806125530276749e-25, 1e-24, -24 }, |
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['z'-'E']= { 8.4703294725430034e-22, 1e-21, -21 }, |
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['a'-'E']= { 8.6736173798840355e-19, 1e-18, -18 }, |
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['f'-'E']= { 8.8817841970012523e-16, 1e-15, -15 }, |
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['p'-'E']= { 9.0949470177292824e-13, 1e-12, -12 }, |
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['n'-'E']= { 9.3132257461547852e-10, 1e-9, -9 }, |
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['u'-'E']= { 9.5367431640625e-7, 1e-6, -6 }, |
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['m'-'E']= { 9.765625e-4, 1e-3, -3 }, |
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['c'-'E']= { 9.8431332023036951e-3, 1e-2, -2 }, |
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['d'-'E']= { 9.921256574801246e-2, 1e-1, -1 }, |
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['h'-'E']= { 1.0159366732596479e2, 1e2, 2 }, |
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['k'-'E']= { 1.024e3, 1e3, 3 }, |
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['K'-'E']= { 1.024e3, 1e3, 3 }, |
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['M'-'E']= { 1.048576e6, 1e6, 6 }, |
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['G'-'E']= { 1.073741824e9, 1e9, 9 }, |
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['T'-'E']= { 1.099511627776e12, 1e12, 12 }, |
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['P'-'E']= { 1.125899906842624e15, 1e15, 15 }, |
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['E'-'E']= { 1.152921504606847e18, 1e18, 18 }, |
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['Z'-'E']= { 1.1805916207174113e21, 1e21, 21 }, |
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['Y'-'E']= { 1.2089258196146292e24, 1e24, 24 }, |
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}; |
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static const struct { |
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const char *name; |
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double value; |
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} constants[] = { |
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{ "E", M_E }, |
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{ "PI", M_PI }, |
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{ "PHI", M_PHI }, |
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{ "QP2LAMBDA", FF_QP2LAMBDA }, |
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}; |
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double av_strtod(const char *numstr, char **tail) |
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{ |
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double d; |
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char *next; |
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if(numstr[0]=='0' && (numstr[1]|0x20)=='x') { |
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d = strtoul(numstr, &next, 16); |
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} else |
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d = strtod(numstr, &next); |
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/* if parsing succeeded, check for and interpret postfixes */ |
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if (next!=numstr) { |
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if (next[0] == 'd' && next[1] == 'B') { |
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/* treat dB as decibels instead of decibytes */ |
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d = ff_exp10(d / 20); |
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next += 2; |
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} else if (*next >= 'E' && *next <= 'z') { |
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int e= si_prefixes[*next - 'E'].exp; |
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if (e) { |
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if (next[1] == 'i') { |
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d*= si_prefixes[*next - 'E'].bin_val; |
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next+=2; |
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} else { |
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d*= si_prefixes[*next - 'E'].dec_val; |
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next++; |
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} |
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} |
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} |
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if (*next=='B') { |
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d*=8; |
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next++; |
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} |
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} |
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/* if requested, fill in tail with the position after the last parsed |
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character */ |
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if (tail) |
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*tail = next; |
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return d; |
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} |
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#define IS_IDENTIFIER_CHAR(c) ((c) - '0' <= 9U || (c) - 'a' <= 25U || (c) - 'A' <= 25U || (c) == '_') |
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static int strmatch(const char *s, const char *prefix) |
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{ |
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int i; |
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for (i=0; prefix[i]; i++) { |
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if (prefix[i] != s[i]) return 0; |
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} |
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/* return 1 only if the s identifier is terminated */ |
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return !IS_IDENTIFIER_CHAR(s[i]); |
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} |
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struct AVExpr { |
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enum { |
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e_value, e_const, e_func0, e_func1, e_func2, |
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e_squish, e_gauss, e_ld, e_isnan, e_isinf, |
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e_mod, e_max, e_min, e_eq, e_gt, e_gte, e_lte, e_lt, |
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e_pow, e_mul, e_div, e_add, |
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e_last, e_st, e_while, e_taylor, e_root, e_floor, e_ceil, e_trunc, e_round, |
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e_sqrt, e_not, e_random, e_hypot, e_gcd, |
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e_if, e_ifnot, e_print, e_bitand, e_bitor, e_between, e_clip, e_atan2, e_lerp, |
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} type; |
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double value; // is sign in other types |
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union { |
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int const_index; |
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double (*func0)(double); |
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double (*func1)(void *, double); |
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double (*func2)(void *, double, double); |
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} a; |
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struct AVExpr *param[3]; |
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double *var; |
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}; |
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static double etime(double v) |
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{ |
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return av_gettime() * 0.000001; |
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} |
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static double eval_expr(Parser *p, AVExpr *e) |
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{ |
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switch (e->type) { |
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case e_value: return e->value; |
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case e_const: return e->value * p->const_values[e->a.const_index]; |
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case e_func0: return e->value * e->a.func0(eval_expr(p, e->param[0])); |
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case e_func1: return e->value * e->a.func1(p->opaque, eval_expr(p, e->param[0])); |
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case e_func2: return e->value * e->a.func2(p->opaque, eval_expr(p, e->param[0]), eval_expr(p, e->param[1])); |
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case e_squish: return 1/(1+exp(4*eval_expr(p, e->param[0]))); |
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case e_gauss: { double d = eval_expr(p, e->param[0]); return exp(-d*d/2)/sqrt(2*M_PI); } |
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case e_ld: return e->value * p->var[av_clip(eval_expr(p, e->param[0]), 0, VARS-1)]; |
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case e_isnan: return e->value * !!isnan(eval_expr(p, e->param[0])); |
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case e_isinf: return e->value * !!isinf(eval_expr(p, e->param[0])); |
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case e_floor: return e->value * floor(eval_expr(p, e->param[0])); |
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case e_ceil : return e->value * ceil (eval_expr(p, e->param[0])); |
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case e_trunc: return e->value * trunc(eval_expr(p, e->param[0])); |
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case e_round: return e->value * round(eval_expr(p, e->param[0])); |
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case e_sqrt: return e->value * sqrt (eval_expr(p, e->param[0])); |
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case e_not: return e->value * (eval_expr(p, e->param[0]) == 0); |
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case e_if: return e->value * (eval_expr(p, e->param[0]) ? eval_expr(p, e->param[1]) : |
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e->param[2] ? eval_expr(p, e->param[2]) : 0); |
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case e_ifnot: return e->value * (!eval_expr(p, e->param[0]) ? eval_expr(p, e->param[1]) : |
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e->param[2] ? eval_expr(p, e->param[2]) : 0); |
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case e_clip: { |
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double x = eval_expr(p, e->param[0]); |
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double min = eval_expr(p, e->param[1]), max = eval_expr(p, e->param[2]); |
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if (isnan(min) || isnan(max) || isnan(x) || min > max) |
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return NAN; |
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return e->value * av_clipd(eval_expr(p, e->param[0]), min, max); |
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} |
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case e_between: { |
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double d = eval_expr(p, e->param[0]); |
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return e->value * (d >= eval_expr(p, e->param[1]) && |
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d <= eval_expr(p, e->param[2])); |
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} |
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case e_lerp: { |
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double v0 = eval_expr(p, e->param[0]); |
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double v1 = eval_expr(p, e->param[1]); |
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double f = eval_expr(p, e->param[2]); |
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return v0 + (v1 - v0) * f; |
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} |
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case e_print: { |
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double x = eval_expr(p, e->param[0]); |
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int level = e->param[1] ? av_clip(eval_expr(p, e->param[1]), INT_MIN, INT_MAX) : AV_LOG_INFO; |
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av_log(p, level, "%f\n", x); |
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return x; |
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} |
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case e_random:{ |
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int idx= av_clip(eval_expr(p, e->param[0]), 0, VARS-1); |
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uint64_t r= isnan(p->var[idx]) ? 0 : p->var[idx]; |
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r= r*1664525+1013904223; |
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p->var[idx]= r; |
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return e->value * (r * (1.0/UINT64_MAX)); |
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} |
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case e_while: { |
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double d = NAN; |
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while (eval_expr(p, e->param[0])) |
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d=eval_expr(p, e->param[1]); |
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return d; |
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} |
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case e_taylor: { |
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double t = 1, d = 0, v; |
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double x = eval_expr(p, e->param[1]); |
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int id = e->param[2] ? av_clip(eval_expr(p, e->param[2]), 0, VARS-1) : 0; |
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int i; |
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double var0 = p->var[id]; |
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for(i=0; i<1000; i++) { |
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double ld = d; |
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p->var[id] = i; |
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v = eval_expr(p, e->param[0]); |
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d += t*v; |
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if(ld==d && v) |
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break; |
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t *= x / (i+1); |
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} |
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p->var[id] = var0; |
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return d; |
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} |
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case e_root: { |
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int i, j; |
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double low = -1, high = -1, v, low_v = -DBL_MAX, high_v = DBL_MAX; |
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double var0 = p->var[0]; |
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double x_max = eval_expr(p, e->param[1]); |
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for(i=-1; i<1024; i++) { |
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if(i<255) { |
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p->var[0] = ff_reverse[i&255]*x_max/255; |
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} else { |
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p->var[0] = x_max*pow(0.9, i-255); |
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if (i&1) p->var[0] *= -1; |
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if (i&2) p->var[0] += low; |
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else p->var[0] += high; |
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} |
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v = eval_expr(p, e->param[0]); |
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if (v<=0 && v>low_v) { |
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low = p->var[0]; |
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low_v = v; |
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} |
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if (v>=0 && v<high_v) { |
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high = p->var[0]; |
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high_v = v; |
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} |
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if (low>=0 && high>=0){ |
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for (j=0; j<1000; j++) { |
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p->var[0] = (low+high)*0.5; |
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if (low == p->var[0] || high == p->var[0]) |
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break; |
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v = eval_expr(p, e->param[0]); |
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if (v<=0) low = p->var[0]; |
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if (v>=0) high= p->var[0]; |
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if (isnan(v)) { |
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low = high = v; |
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break; |
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} |
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} |
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break; |
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} |
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} |
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p->var[0] = var0; |
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return -low_v<high_v ? low : high; |
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} |
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default: { |
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double d = eval_expr(p, e->param[0]); |
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double d2 = eval_expr(p, e->param[1]); |
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switch (e->type) { |
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case e_mod: return e->value * (d - floor((!CONFIG_FTRAPV || d2) ? d / d2 : d * INFINITY) * d2); |
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case e_gcd: return e->value * av_gcd(d,d2); |
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case e_max: return e->value * (d > d2 ? d : d2); |
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case e_min: return e->value * (d < d2 ? d : d2); |
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case e_eq: return e->value * (d == d2 ? 1.0 : 0.0); |
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case e_gt: return e->value * (d > d2 ? 1.0 : 0.0); |
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case e_gte: return e->value * (d >= d2 ? 1.0 : 0.0); |
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case e_lt: return e->value * (d < d2 ? 1.0 : 0.0); |
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case e_lte: return e->value * (d <= d2 ? 1.0 : 0.0); |
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case e_pow: return e->value * pow(d, d2); |
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case e_mul: return e->value * (d * d2); |
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case e_div: return e->value * ((!CONFIG_FTRAPV || d2 ) ? (d / d2) : d * INFINITY); |
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case e_add: return e->value * (d + d2); |
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case e_last:return e->value * d2; |
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case e_st : return e->value * (p->var[av_clip(d, 0, VARS-1)]= d2); |
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case e_hypot:return e->value * hypot(d, d2); |
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case e_atan2:return e->value * atan2(d, d2); |
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case e_bitand: return isnan(d) || isnan(d2) ? NAN : e->value * ((long int)d & (long int)d2); |
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case e_bitor: return isnan(d) || isnan(d2) ? NAN : e->value * ((long int)d | (long int)d2); |
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} |
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} |
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} |
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return NAN; |
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} |
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static int parse_expr(AVExpr **e, Parser *p); |
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void av_expr_free(AVExpr *e) |
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{ |
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if (!e) return; |
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av_expr_free(e->param[0]); |
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av_expr_free(e->param[1]); |
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av_expr_free(e->param[2]); |
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av_freep(&e->var); |
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av_freep(&e); |
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} |
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static int parse_primary(AVExpr **e, Parser *p) |
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{ |
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AVExpr *d = av_mallocz(sizeof(AVExpr)); |
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char *next = p->s, *s0 = p->s; |
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int ret, i; |
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if (!d) |
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return AVERROR(ENOMEM); |
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/* number */ |
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d->value = av_strtod(p->s, &next); |
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if (next != p->s) { |
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d->type = e_value; |
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p->s= next; |
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*e = d; |
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return 0; |
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} |
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d->value = 1; |
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/* named constants */ |
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for (i=0; p->const_names && p->const_names[i]; i++) { |
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if (strmatch(p->s, p->const_names[i])) { |
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p->s+= strlen(p->const_names[i]); |
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d->type = e_const; |
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d->a.const_index = i; |
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*e = d; |
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return 0; |
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} |
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} |
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for (i = 0; i < FF_ARRAY_ELEMS(constants); i++) { |
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if (strmatch(p->s, constants[i].name)) { |
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p->s += strlen(constants[i].name); |
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d->type = e_value; |
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d->value = constants[i].value; |
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*e = d; |
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return 0; |
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} |
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} |
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p->s= strchr(p->s, '('); |
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if (!p->s) { |
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av_log(p, AV_LOG_ERROR, "Undefined constant or missing '(' in '%s'\n", s0); |
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p->s= next; |
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av_expr_free(d); |
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return AVERROR(EINVAL); |
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} |
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p->s++; // "(" |
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if (*next == '(') { // special case do-nothing |
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av_freep(&d); |
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if ((ret = parse_expr(&d, p)) < 0) |
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return ret; |
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if (p->s[0] != ')') { |
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av_log(p, AV_LOG_ERROR, "Missing ')' in '%s'\n", s0); |
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av_expr_free(d); |
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return AVERROR(EINVAL); |
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} |
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p->s++; // ")" |
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*e = d; |
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return 0; |
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} |
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if ((ret = parse_expr(&(d->param[0]), p)) < 0) { |
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av_expr_free(d); |
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return ret; |
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} |
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if (p->s[0]== ',') { |
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p->s++; // "," |
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parse_expr(&d->param[1], p); |
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} |
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if (p->s[0]== ',') { |
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p->s++; // "," |
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parse_expr(&d->param[2], p); |
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} |
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if (p->s[0] != ')') { |
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av_log(p, AV_LOG_ERROR, "Missing ')' or too many args in '%s'\n", s0); |
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av_expr_free(d); |
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return AVERROR(EINVAL); |
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} |
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p->s++; // ")" |
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|
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d->type = e_func0; |
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if (strmatch(next, "sinh" )) d->a.func0 = sinh; |
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else if (strmatch(next, "cosh" )) d->a.func0 = cosh; |
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else if (strmatch(next, "tanh" )) d->a.func0 = tanh; |
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else if (strmatch(next, "sin" )) d->a.func0 = sin; |
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else if (strmatch(next, "cos" )) d->a.func0 = cos; |
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else if (strmatch(next, "tan" )) d->a.func0 = tan; |
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else if (strmatch(next, "atan" )) d->a.func0 = atan; |
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else if (strmatch(next, "asin" )) d->a.func0 = asin; |
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else if (strmatch(next, "acos" )) d->a.func0 = acos; |
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else if (strmatch(next, "exp" )) d->a.func0 = exp; |
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else if (strmatch(next, "log" )) d->a.func0 = log; |
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else if (strmatch(next, "abs" )) d->a.func0 = fabs; |
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else if (strmatch(next, "time" )) d->a.func0 = etime; |
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else if (strmatch(next, "squish")) d->type = e_squish; |
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else if (strmatch(next, "gauss" )) d->type = e_gauss; |
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else if (strmatch(next, "mod" )) d->type = e_mod; |
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else if (strmatch(next, "max" )) d->type = e_max; |
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else if (strmatch(next, "min" )) d->type = e_min; |
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else if (strmatch(next, "eq" )) d->type = e_eq; |
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else if (strmatch(next, "gte" )) d->type = e_gte; |
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else if (strmatch(next, "gt" )) d->type = e_gt; |
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else if (strmatch(next, "lte" )) d->type = e_lte; |
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else if (strmatch(next, "lt" )) d->type = e_lt; |
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else if (strmatch(next, "ld" )) d->type = e_ld; |
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else if (strmatch(next, "isnan" )) d->type = e_isnan; |
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else if (strmatch(next, "isinf" )) d->type = e_isinf; |
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else if (strmatch(next, "st" )) d->type = e_st; |
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else if (strmatch(next, "while" )) d->type = e_while; |
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else if (strmatch(next, "taylor")) d->type = e_taylor; |
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else if (strmatch(next, "root" )) d->type = e_root; |
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else if (strmatch(next, "floor" )) d->type = e_floor; |
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else if (strmatch(next, "ceil" )) d->type = e_ceil; |
|
else if (strmatch(next, "trunc" )) d->type = e_trunc; |
|
else if (strmatch(next, "round" )) d->type = e_round; |
|
else if (strmatch(next, "sqrt" )) d->type = e_sqrt; |
|
else if (strmatch(next, "not" )) d->type = e_not; |
|
else if (strmatch(next, "pow" )) d->type = e_pow; |
|
else if (strmatch(next, "print" )) d->type = e_print; |
|
else if (strmatch(next, "random")) d->type = e_random; |
|
else if (strmatch(next, "hypot" )) d->type = e_hypot; |
|
else if (strmatch(next, "gcd" )) d->type = e_gcd; |
|
else if (strmatch(next, "if" )) d->type = e_if; |
|
else if (strmatch(next, "ifnot" )) d->type = e_ifnot; |
|
else if (strmatch(next, "bitand")) d->type = e_bitand; |
|
else if (strmatch(next, "bitor" )) d->type = e_bitor; |
|
else if (strmatch(next, "between"))d->type = e_between; |
|
else if (strmatch(next, "clip" )) d->type = e_clip; |
|
else if (strmatch(next, "atan2" )) d->type = e_atan2; |
|
else if (strmatch(next, "lerp" )) d->type = e_lerp; |
|
else { |
|
for (i=0; p->func1_names && p->func1_names[i]; i++) { |
|
if (strmatch(next, p->func1_names[i])) { |
|
d->a.func1 = p->funcs1[i]; |
|
d->type = e_func1; |
|
*e = d; |
|
return 0; |
|
} |
|
} |
|
|
|
for (i=0; p->func2_names && p->func2_names[i]; i++) { |
|
if (strmatch(next, p->func2_names[i])) { |
|
d->a.func2 = p->funcs2[i]; |
|
d->type = e_func2; |
|
*e = d; |
|
return 0; |
|
} |
|
} |
|
|
|
av_log(p, AV_LOG_ERROR, "Unknown function in '%s'\n", s0); |
|
av_expr_free(d); |
|
return AVERROR(EINVAL); |
|
} |
|
|
|
*e = d; |
|
return 0; |
|
} |
|
|
|
static AVExpr *make_eval_expr(int type, int value, AVExpr *p0, AVExpr *p1) |
|
{ |
|
AVExpr *e = av_mallocz(sizeof(AVExpr)); |
|
if (!e) |
|
return NULL; |
|
e->type =type ; |
|
e->value =value ; |
|
e->param[0] =p0 ; |
|
e->param[1] =p1 ; |
|
return e; |
|
} |
|
|
|
static int parse_pow(AVExpr **e, Parser *p, int *sign) |
|
{ |
|
*sign= (*p->s == '+') - (*p->s == '-'); |
|
p->s += *sign&1; |
|
return parse_primary(e, p); |
|
} |
|
|
|
static int parse_dB(AVExpr **e, Parser *p, int *sign) |
|
{ |
|
/* do not filter out the negative sign when parsing a dB value. |
|
for example, -3dB is not the same as -(3dB) */ |
|
if (*p->s == '-') { |
|
char *next; |
|
double av_unused ignored = strtod(p->s, &next); |
|
if (next != p->s && next[0] == 'd' && next[1] == 'B') { |
|
*sign = 0; |
|
return parse_primary(e, p); |
|
} |
|
} |
|
return parse_pow(e, p, sign); |
|
} |
|
|
|
static int parse_factor(AVExpr **e, Parser *p) |
|
{ |
|
int sign, sign2, ret; |
|
AVExpr *e0, *e1, *e2; |
|
if ((ret = parse_dB(&e0, p, &sign)) < 0) |
|
return ret; |
|
while(p->s[0]=='^'){ |
|
e1 = e0; |
|
p->s++; |
|
if ((ret = parse_dB(&e2, p, &sign2)) < 0) { |
|
av_expr_free(e1); |
|
return ret; |
|
} |
|
e0 = make_eval_expr(e_pow, 1, e1, e2); |
|
if (!e0) { |
|
av_expr_free(e1); |
|
av_expr_free(e2); |
|
return AVERROR(ENOMEM); |
|
} |
|
if (e0->param[1]) e0->param[1]->value *= (sign2|1); |
|
} |
|
if (e0) e0->value *= (sign|1); |
|
|
|
*e = e0; |
|
return 0; |
|
} |
|
|
|
static int parse_term(AVExpr **e, Parser *p) |
|
{ |
|
int ret; |
|
AVExpr *e0, *e1, *e2; |
|
if ((ret = parse_factor(&e0, p)) < 0) |
|
return ret; |
|
while (p->s[0]=='*' || p->s[0]=='/') { |
|
int c= *p->s++; |
|
e1 = e0; |
|
if ((ret = parse_factor(&e2, p)) < 0) { |
|
av_expr_free(e1); |
|
return ret; |
|
} |
|
e0 = make_eval_expr(c == '*' ? e_mul : e_div, 1, e1, e2); |
|
if (!e0) { |
|
av_expr_free(e1); |
|
av_expr_free(e2); |
|
return AVERROR(ENOMEM); |
|
} |
|
} |
|
*e = e0; |
|
return 0; |
|
} |
|
|
|
static int parse_subexpr(AVExpr **e, Parser *p) |
|
{ |
|
int ret; |
|
AVExpr *e0, *e1, *e2; |
|
if ((ret = parse_term(&e0, p)) < 0) |
|
return ret; |
|
while (*p->s == '+' || *p->s == '-') { |
|
e1 = e0; |
|
if ((ret = parse_term(&e2, p)) < 0) { |
|
av_expr_free(e1); |
|
return ret; |
|
} |
|
e0 = make_eval_expr(e_add, 1, e1, e2); |
|
if (!e0) { |
|
av_expr_free(e1); |
|
av_expr_free(e2); |
|
return AVERROR(ENOMEM); |
|
} |
|
}; |
|
|
|
*e = e0; |
|
return 0; |
|
} |
|
|
|
static int parse_expr(AVExpr **e, Parser *p) |
|
{ |
|
int ret; |
|
AVExpr *e0, *e1, *e2; |
|
if (p->stack_index <= 0) //protect against stack overflows |
|
return AVERROR(EINVAL); |
|
p->stack_index--; |
|
|
|
if ((ret = parse_subexpr(&e0, p)) < 0) |
|
return ret; |
|
while (*p->s == ';') { |
|
p->s++; |
|
e1 = e0; |
|
if ((ret = parse_subexpr(&e2, p)) < 0) { |
|
av_expr_free(e1); |
|
return ret; |
|
} |
|
e0 = make_eval_expr(e_last, 1, e1, e2); |
|
if (!e0) { |
|
av_expr_free(e1); |
|
av_expr_free(e2); |
|
return AVERROR(ENOMEM); |
|
} |
|
}; |
|
|
|
p->stack_index++; |
|
*e = e0; |
|
return 0; |
|
} |
|
|
|
static int verify_expr(AVExpr *e) |
|
{ |
|
if (!e) return 0; |
|
switch (e->type) { |
|
case e_value: |
|
case e_const: return 1; |
|
case e_func0: |
|
case e_func1: |
|
case e_squish: |
|
case e_ld: |
|
case e_gauss: |
|
case e_isnan: |
|
case e_isinf: |
|
case e_floor: |
|
case e_ceil: |
|
case e_trunc: |
|
case e_round: |
|
case e_sqrt: |
|
case e_not: |
|
case e_random: |
|
return verify_expr(e->param[0]) && !e->param[1]; |
|
case e_print: |
|
return verify_expr(e->param[0]) |
|
&& (!e->param[1] || verify_expr(e->param[1])); |
|
case e_if: |
|
case e_ifnot: |
|
case e_taylor: |
|
return verify_expr(e->param[0]) && verify_expr(e->param[1]) |
|
&& (!e->param[2] || verify_expr(e->param[2])); |
|
case e_between: |
|
case e_clip: |
|
case e_lerp: |
|
return verify_expr(e->param[0]) && |
|
verify_expr(e->param[1]) && |
|
verify_expr(e->param[2]); |
|
default: return verify_expr(e->param[0]) && verify_expr(e->param[1]) && !e->param[2]; |
|
} |
|
} |
|
|
|
int av_expr_parse(AVExpr **expr, const char *s, |
|
const char * const *const_names, |
|
const char * const *func1_names, double (* const *funcs1)(void *, double), |
|
const char * const *func2_names, double (* const *funcs2)(void *, double, double), |
|
int log_offset, void *log_ctx) |
|
{ |
|
Parser p = { 0 }; |
|
AVExpr *e = NULL; |
|
char *w = av_malloc(strlen(s) + 1); |
|
char *wp = w; |
|
const char *s0 = s; |
|
int ret = 0; |
|
|
|
if (!w) |
|
return AVERROR(ENOMEM); |
|
|
|
while (*s) |
|
if (!av_isspace(*s++)) *wp++ = s[-1]; |
|
*wp++ = 0; |
|
|
|
p.class = &eval_class; |
|
p.stack_index=100; |
|
p.s= w; |
|
p.const_names = const_names; |
|
p.funcs1 = funcs1; |
|
p.func1_names = func1_names; |
|
p.funcs2 = funcs2; |
|
p.func2_names = func2_names; |
|
p.log_offset = log_offset; |
|
p.log_ctx = log_ctx; |
|
|
|
if ((ret = parse_expr(&e, &p)) < 0) |
|
goto end; |
|
if (*p.s) { |
|
av_log(&p, AV_LOG_ERROR, "Invalid chars '%s' at the end of expression '%s'\n", p.s, s0); |
|
ret = AVERROR(EINVAL); |
|
goto end; |
|
} |
|
if (!verify_expr(e)) { |
|
ret = AVERROR(EINVAL); |
|
goto end; |
|
} |
|
e->var= av_mallocz(sizeof(double) *VARS); |
|
if (!e->var) { |
|
ret = AVERROR(ENOMEM); |
|
goto end; |
|
} |
|
*expr = e; |
|
e = NULL; |
|
end: |
|
av_expr_free(e); |
|
av_free(w); |
|
return ret; |
|
} |
|
|
|
double av_expr_eval(AVExpr *e, const double *const_values, void *opaque) |
|
{ |
|
Parser p = { 0 }; |
|
p.var= e->var; |
|
|
|
p.const_values = const_values; |
|
p.opaque = opaque; |
|
return eval_expr(&p, e); |
|
} |
|
|
|
int av_expr_parse_and_eval(double *d, const char *s, |
|
const char * const *const_names, const double *const_values, |
|
const char * const *func1_names, double (* const *funcs1)(void *, double), |
|
const char * const *func2_names, double (* const *funcs2)(void *, double, double), |
|
void *opaque, int log_offset, void *log_ctx) |
|
{ |
|
AVExpr *e = NULL; |
|
int ret = av_expr_parse(&e, s, const_names, func1_names, funcs1, func2_names, funcs2, log_offset, log_ctx); |
|
|
|
if (ret < 0) { |
|
*d = NAN; |
|
return ret; |
|
} |
|
*d = av_expr_eval(e, const_values, opaque); |
|
av_expr_free(e); |
|
return isnan(*d) ? AVERROR(EINVAL) : 0; |
|
}
|
|
|