• Main Page
  • Related Pages
  • Modules
  • Data Structures
  • Files
  • Examples
  • File List
  • Globals

libavutil/eval.c

Go to the documentation of this file.
00001 /*
00002  * Copyright (c) 2002-2006 Michael Niedermayer <michaelni@gmx.at>
00003  * Copyright (c) 2006 Oded Shimon <ods15@ods15.dyndns.org>
00004  *
00005  * This file is part of Libav.
00006  *
00007  * Libav is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * Libav is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with Libav; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00029 #include "avutil.h"
00030 #include "eval.h"
00031 #include "log.h"
00032 
00033 typedef struct Parser {
00034     const AVClass *class;
00035     int stack_index;
00036     char *s;
00037     const double *const_values;
00038     const char * const *const_names;          // NULL terminated
00039     double (* const *funcs1)(void *, double a);           // NULL terminated
00040     const char * const *func1_names;          // NULL terminated
00041     double (* const *funcs2)(void *, double a, double b); // NULL terminated
00042     const char * const *func2_names;          // NULL terminated
00043     void *opaque;
00044     int log_offset;
00045     void *log_ctx;
00046 #define VARS 10
00047     double var[VARS];
00048 } Parser;
00049 
00050 static const AVClass class = { "Eval", av_default_item_name, NULL, LIBAVUTIL_VERSION_INT, offsetof(Parser,log_offset), offsetof(Parser,log_ctx) };
00051 
00052 static const int8_t si_prefixes['z' - 'E' + 1] = {
00053     ['y'-'E']= -24,
00054     ['z'-'E']= -21,
00055     ['a'-'E']= -18,
00056     ['f'-'E']= -15,
00057     ['p'-'E']= -12,
00058     ['n'-'E']= - 9,
00059     ['u'-'E']= - 6,
00060     ['m'-'E']= - 3,
00061     ['c'-'E']= - 2,
00062     ['d'-'E']= - 1,
00063     ['h'-'E']=   2,
00064     ['k'-'E']=   3,
00065     ['K'-'E']=   3,
00066     ['M'-'E']=   6,
00067     ['G'-'E']=   9,
00068     ['T'-'E']=  12,
00069     ['P'-'E']=  15,
00070     ['E'-'E']=  18,
00071     ['Z'-'E']=  21,
00072     ['Y'-'E']=  24,
00073 };
00074 
00075 double av_strtod(const char *numstr, char **tail)
00076 {
00077     double d;
00078     char *next;
00079     d = strtod(numstr, &next);
00080     /* if parsing succeeded, check for and interpret postfixes */
00081     if (next!=numstr) {
00082         if (*next >= 'E' && *next <= 'z') {
00083             int e= si_prefixes[*next - 'E'];
00084             if (e) {
00085                 if (next[1] == 'i') {
00086                     d*= pow( 2, e/0.3);
00087                     next+=2;
00088                 } else {
00089                     d*= pow(10, e);
00090                     next++;
00091                 }
00092             }
00093         }
00094 
00095         if (*next=='B') {
00096             d*=8;
00097             next++;
00098         }
00099     }
00100     /* if requested, fill in tail with the position after the last parsed
00101        character */
00102     if (tail)
00103         *tail = next;
00104     return d;
00105 }
00106 
00107 #define IS_IDENTIFIER_CHAR(c) ((c) - '0' <= 9U || (c) - 'a' <= 25U || (c) - 'A' <= 25U || (c) == '_')
00108 
00109 static int strmatch(const char *s, const char *prefix)
00110 {
00111     int i;
00112     for (i=0; prefix[i]; i++) {
00113         if (prefix[i] != s[i]) return 0;
00114     }
00115     /* return 1 only if the s identifier is terminated */
00116     return !IS_IDENTIFIER_CHAR(s[i]);
00117 }
00118 
00119 struct AVExpr {
00120     enum {
00121         e_value, e_const, e_func0, e_func1, e_func2,
00122         e_squish, e_gauss, e_ld, e_isnan,
00123         e_mod, e_max, e_min, e_eq, e_gt, e_gte,
00124         e_pow, e_mul, e_div, e_add,
00125         e_last, e_st, e_while, e_floor, e_ceil, e_trunc,
00126         e_sqrt, e_not,
00127     } type;
00128     double value; // is sign in other types
00129     union {
00130         int const_index;
00131         double (*func0)(double);
00132         double (*func1)(void *, double);
00133         double (*func2)(void *, double, double);
00134     } a;
00135     struct AVExpr *param[2];
00136 };
00137 
00138 static double eval_expr(Parser *p, AVExpr *e)
00139 {
00140     switch (e->type) {
00141         case e_value:  return e->value;
00142         case e_const:  return e->value * p->const_values[e->a.const_index];
00143         case e_func0:  return e->value * e->a.func0(eval_expr(p, e->param[0]));
00144         case e_func1:  return e->value * e->a.func1(p->opaque, eval_expr(p, e->param[0]));
00145         case e_func2:  return e->value * e->a.func2(p->opaque, eval_expr(p, e->param[0]), eval_expr(p, e->param[1]));
00146         case e_squish: return 1/(1+exp(4*eval_expr(p, e->param[0])));
00147         case e_gauss: { double d = eval_expr(p, e->param[0]); return exp(-d*d/2)/sqrt(2*M_PI); }
00148         case e_ld:     return e->value * p->var[av_clip(eval_expr(p, e->param[0]), 0, VARS-1)];
00149         case e_isnan:  return e->value * !!isnan(eval_expr(p, e->param[0]));
00150         case e_floor:  return e->value * floor(eval_expr(p, e->param[0]));
00151         case e_ceil :  return e->value * ceil (eval_expr(p, e->param[0]));
00152         case e_trunc:  return e->value * trunc(eval_expr(p, e->param[0]));
00153         case e_sqrt:   return e->value * sqrt (eval_expr(p, e->param[0]));
00154         case e_not:    return e->value * eval_expr(p, e->param[0]) == 0;
00155         case e_while: {
00156             double d = NAN;
00157             while (eval_expr(p, e->param[0]))
00158                 d=eval_expr(p, e->param[1]);
00159             return d;
00160         }
00161         default: {
00162             double d = eval_expr(p, e->param[0]);
00163             double d2 = eval_expr(p, e->param[1]);
00164             switch (e->type) {
00165                 case e_mod: return e->value * (d - floor(d/d2)*d2);
00166                 case e_max: return e->value * (d >  d2 ?   d : d2);
00167                 case e_min: return e->value * (d <  d2 ?   d : d2);
00168                 case e_eq:  return e->value * (d == d2 ? 1.0 : 0.0);
00169                 case e_gt:  return e->value * (d >  d2 ? 1.0 : 0.0);
00170                 case e_gte: return e->value * (d >= d2 ? 1.0 : 0.0);
00171                 case e_pow: return e->value * pow(d, d2);
00172                 case e_mul: return e->value * (d * d2);
00173                 case e_div: return e->value * (d / d2);
00174                 case e_add: return e->value * (d + d2);
00175                 case e_last:return e->value * d2;
00176                 case e_st : return e->value * (p->var[av_clip(d, 0, VARS-1)]= d2);
00177             }
00178         }
00179     }
00180     return NAN;
00181 }
00182 
00183 static int parse_expr(AVExpr **e, Parser *p);
00184 
00185 void av_expr_free(AVExpr *e)
00186 {
00187     if (!e) return;
00188     av_expr_free(e->param[0]);
00189     av_expr_free(e->param[1]);
00190     av_freep(&e);
00191 }
00192 
00193 static int parse_primary(AVExpr **e, Parser *p)
00194 {
00195     AVExpr *d = av_mallocz(sizeof(AVExpr));
00196     char *next = p->s, *s0 = p->s;
00197     int ret, i;
00198 
00199     if (!d)
00200         return AVERROR(ENOMEM);
00201 
00202     /* number */
00203     d->value = av_strtod(p->s, &next);
00204     if (next != p->s) {
00205         d->type = e_value;
00206         p->s= next;
00207         *e = d;
00208         return 0;
00209     }
00210     d->value = 1;
00211 
00212     /* named constants */
00213     for (i=0; p->const_names && p->const_names[i]; i++) {
00214         if (strmatch(p->s, p->const_names[i])) {
00215             p->s+= strlen(p->const_names[i]);
00216             d->type = e_const;
00217             d->a.const_index = i;
00218             *e = d;
00219             return 0;
00220         }
00221     }
00222 
00223     p->s= strchr(p->s, '(');
00224     if (p->s==NULL) {
00225         av_log(p, AV_LOG_ERROR, "Undefined constant or missing '(' in '%s'\n", s0);
00226         p->s= next;
00227         av_expr_free(d);
00228         return AVERROR(EINVAL);
00229     }
00230     p->s++; // "("
00231     if (*next == '(') { // special case do-nothing
00232         av_freep(&d);
00233         if ((ret = parse_expr(&d, p)) < 0)
00234             return ret;
00235         if (p->s[0] != ')') {
00236             av_log(p, AV_LOG_ERROR, "Missing ')' in '%s'\n", s0);
00237             av_expr_free(d);
00238             return AVERROR(EINVAL);
00239         }
00240         p->s++; // ")"
00241         *e = d;
00242         return 0;
00243     }
00244     if ((ret = parse_expr(&(d->param[0]), p)) < 0) {
00245         av_expr_free(d);
00246         return ret;
00247     }
00248     if (p->s[0]== ',') {
00249         p->s++; // ","
00250         parse_expr(&d->param[1], p);
00251     }
00252     if (p->s[0] != ')') {
00253         av_log(p, AV_LOG_ERROR, "Missing ')' or too many args in '%s'\n", s0);
00254         av_expr_free(d);
00255         return AVERROR(EINVAL);
00256     }
00257     p->s++; // ")"
00258 
00259     d->type = e_func0;
00260          if (strmatch(next, "sinh"  )) d->a.func0 = sinh;
00261     else if (strmatch(next, "cosh"  )) d->a.func0 = cosh;
00262     else if (strmatch(next, "tanh"  )) d->a.func0 = tanh;
00263     else if (strmatch(next, "sin"   )) d->a.func0 = sin;
00264     else if (strmatch(next, "cos"   )) d->a.func0 = cos;
00265     else if (strmatch(next, "tan"   )) d->a.func0 = tan;
00266     else if (strmatch(next, "atan"  )) d->a.func0 = atan;
00267     else if (strmatch(next, "asin"  )) d->a.func0 = asin;
00268     else if (strmatch(next, "acos"  )) d->a.func0 = acos;
00269     else if (strmatch(next, "exp"   )) d->a.func0 = exp;
00270     else if (strmatch(next, "log"   )) d->a.func0 = log;
00271     else if (strmatch(next, "abs"   )) d->a.func0 = fabs;
00272     else if (strmatch(next, "squish")) d->type = e_squish;
00273     else if (strmatch(next, "gauss" )) d->type = e_gauss;
00274     else if (strmatch(next, "mod"   )) d->type = e_mod;
00275     else if (strmatch(next, "max"   )) d->type = e_max;
00276     else if (strmatch(next, "min"   )) d->type = e_min;
00277     else if (strmatch(next, "eq"    )) d->type = e_eq;
00278     else if (strmatch(next, "gte"   )) d->type = e_gte;
00279     else if (strmatch(next, "gt"    )) d->type = e_gt;
00280     else if (strmatch(next, "lte"   )) { AVExpr *tmp = d->param[1]; d->param[1] = d->param[0]; d->param[0] = tmp; d->type = e_gt; }
00281     else if (strmatch(next, "lt"    )) { AVExpr *tmp = d->param[1]; d->param[1] = d->param[0]; d->param[0] = tmp; d->type = e_gte; }
00282     else if (strmatch(next, "ld"    )) d->type = e_ld;
00283     else if (strmatch(next, "isnan" )) d->type = e_isnan;
00284     else if (strmatch(next, "st"    )) d->type = e_st;
00285     else if (strmatch(next, "while" )) d->type = e_while;
00286     else if (strmatch(next, "floor" )) d->type = e_floor;
00287     else if (strmatch(next, "ceil"  )) d->type = e_ceil;
00288     else if (strmatch(next, "trunc" )) d->type = e_trunc;
00289     else if (strmatch(next, "sqrt"  )) d->type = e_sqrt;
00290     else if (strmatch(next, "not"   )) d->type = e_not;
00291     else {
00292         for (i=0; p->func1_names && p->func1_names[i]; i++) {
00293             if (strmatch(next, p->func1_names[i])) {
00294                 d->a.func1 = p->funcs1[i];
00295                 d->type = e_func1;
00296                 *e = d;
00297                 return 0;
00298             }
00299         }
00300 
00301         for (i=0; p->func2_names && p->func2_names[i]; i++) {
00302             if (strmatch(next, p->func2_names[i])) {
00303                 d->a.func2 = p->funcs2[i];
00304                 d->type = e_func2;
00305                 *e = d;
00306                 return 0;
00307             }
00308         }
00309 
00310         av_log(p, AV_LOG_ERROR, "Unknown function in '%s'\n", s0);
00311         av_expr_free(d);
00312         return AVERROR(EINVAL);
00313     }
00314 
00315     *e = d;
00316     return 0;
00317 }
00318 
00319 static AVExpr *new_eval_expr(int type, int value, AVExpr *p0, AVExpr *p1)
00320 {
00321     AVExpr *e = av_mallocz(sizeof(AVExpr));
00322     if (!e)
00323         return NULL;
00324     e->type     =type   ;
00325     e->value    =value  ;
00326     e->param[0] =p0     ;
00327     e->param[1] =p1     ;
00328     return e;
00329 }
00330 
00331 static int parse_pow(AVExpr **e, Parser *p, int *sign)
00332 {
00333     *sign= (*p->s == '+') - (*p->s == '-');
00334     p->s += *sign&1;
00335     return parse_primary(e, p);
00336 }
00337 
00338 static int parse_factor(AVExpr **e, Parser *p)
00339 {
00340     int sign, sign2, ret;
00341     AVExpr *e0, *e1, *e2;
00342     if ((ret = parse_pow(&e0, p, &sign)) < 0)
00343         return ret;
00344     while(p->s[0]=='^'){
00345         e1 = e0;
00346         p->s++;
00347         if ((ret = parse_pow(&e2, p, &sign2)) < 0) {
00348             av_expr_free(e1);
00349             return ret;
00350         }
00351         e0 = new_eval_expr(e_pow, 1, e1, e2);
00352         if (!e0) {
00353             av_expr_free(e1);
00354             av_expr_free(e2);
00355             return AVERROR(ENOMEM);
00356         }
00357         if (e0->param[1]) e0->param[1]->value *= (sign2|1);
00358     }
00359     if (e0) e0->value *= (sign|1);
00360 
00361     *e = e0;
00362     return 0;
00363 }
00364 
00365 static int parse_term(AVExpr **e, Parser *p)
00366 {
00367     int ret;
00368     AVExpr *e0, *e1, *e2;
00369     if ((ret = parse_factor(&e0, p)) < 0)
00370         return ret;
00371     while (p->s[0]=='*' || p->s[0]=='/') {
00372         int c= *p->s++;
00373         e1 = e0;
00374         if ((ret = parse_factor(&e2, p)) < 0) {
00375             av_expr_free(e1);
00376             return ret;
00377         }
00378         e0 = new_eval_expr(c == '*' ? e_mul : e_div, 1, e1, e2);
00379         if (!e0) {
00380             av_expr_free(e1);
00381             av_expr_free(e2);
00382             return AVERROR(ENOMEM);
00383         }
00384     }
00385     *e = e0;
00386     return 0;
00387 }
00388 
00389 static int parse_subexpr(AVExpr **e, Parser *p)
00390 {
00391     int ret;
00392     AVExpr *e0, *e1, *e2;
00393     if ((ret = parse_term(&e0, p)) < 0)
00394         return ret;
00395     while (*p->s == '+' || *p->s == '-') {
00396         e1 = e0;
00397         if ((ret = parse_term(&e2, p)) < 0) {
00398             av_expr_free(e1);
00399             return ret;
00400         }
00401         e0 = new_eval_expr(e_add, 1, e1, e2);
00402         if (!e0) {
00403             av_expr_free(e1);
00404             av_expr_free(e2);
00405             return AVERROR(ENOMEM);
00406         }
00407     };
00408 
00409     *e = e0;
00410     return 0;
00411 }
00412 
00413 static int parse_expr(AVExpr **e, Parser *p)
00414 {
00415     int ret;
00416     AVExpr *e0, *e1, *e2;
00417     if (p->stack_index <= 0) //protect against stack overflows
00418         return AVERROR(EINVAL);
00419     p->stack_index--;
00420 
00421     if ((ret = parse_subexpr(&e0, p)) < 0)
00422         return ret;
00423     while (*p->s == ';') {
00424         p->s++;
00425         e1 = e0;
00426         if ((ret = parse_subexpr(&e2, p)) < 0) {
00427             av_expr_free(e1);
00428             return ret;
00429         }
00430         e0 = new_eval_expr(e_last, 1, e1, e2);
00431         if (!e0) {
00432             av_expr_free(e1);
00433             av_expr_free(e2);
00434             return AVERROR(ENOMEM);
00435         }
00436     };
00437 
00438     p->stack_index++;
00439     *e = e0;
00440     return 0;
00441 }
00442 
00443 static int verify_expr(AVExpr *e)
00444 {
00445     if (!e) return 0;
00446     switch (e->type) {
00447         case e_value:
00448         case e_const: return 1;
00449         case e_func0:
00450         case e_func1:
00451         case e_squish:
00452         case e_ld:
00453         case e_gauss:
00454         case e_isnan:
00455         case e_floor:
00456         case e_ceil:
00457         case e_trunc:
00458         case e_sqrt:
00459         case e_not:
00460             return verify_expr(e->param[0]);
00461         default: return verify_expr(e->param[0]) && verify_expr(e->param[1]);
00462     }
00463 }
00464 
00465 int av_expr_parse(AVExpr **expr, const char *s,
00466                   const char * const *const_names,
00467                   const char * const *func1_names, double (* const *funcs1)(void *, double),
00468                   const char * const *func2_names, double (* const *funcs2)(void *, double, double),
00469                   int log_offset, void *log_ctx)
00470 {
00471     Parser p = { 0 };
00472     AVExpr *e = NULL;
00473     char *w = av_malloc(strlen(s) + 1);
00474     char *wp = w;
00475     const char *s0 = s;
00476     int ret = 0;
00477 
00478     if (!w)
00479         return AVERROR(ENOMEM);
00480 
00481     while (*s)
00482         if (!isspace(*s++)) *wp++ = s[-1];
00483     *wp++ = 0;
00484 
00485     p.class      = &class;
00486     p.stack_index=100;
00487     p.s= w;
00488     p.const_names = const_names;
00489     p.funcs1      = funcs1;
00490     p.func1_names = func1_names;
00491     p.funcs2      = funcs2;
00492     p.func2_names = func2_names;
00493     p.log_offset = log_offset;
00494     p.log_ctx    = log_ctx;
00495 
00496     if ((ret = parse_expr(&e, &p)) < 0)
00497         goto end;
00498     if (*p.s) {
00499         av_expr_free(e);
00500         av_log(&p, AV_LOG_ERROR, "Invalid chars '%s' at the end of expression '%s'\n", p.s, s0);
00501         ret = AVERROR(EINVAL);
00502         goto end;
00503     }
00504     if (!verify_expr(e)) {
00505         av_expr_free(e);
00506         ret = AVERROR(EINVAL);
00507         goto end;
00508     }
00509     *expr = e;
00510 end:
00511     av_free(w);
00512     return ret;
00513 }
00514 
00515 double av_expr_eval(AVExpr *e, const double *const_values, void *opaque)
00516 {
00517     Parser p = { 0 };
00518 
00519     p.const_values = const_values;
00520     p.opaque     = opaque;
00521     return eval_expr(&p, e);
00522 }
00523 
00524 int av_expr_parse_and_eval(double *d, const char *s,
00525                            const char * const *const_names, const double *const_values,
00526                            const char * const *func1_names, double (* const *funcs1)(void *, double),
00527                            const char * const *func2_names, double (* const *funcs2)(void *, double, double),
00528                            void *opaque, int log_offset, void *log_ctx)
00529 {
00530     AVExpr *e = NULL;
00531     int ret = av_expr_parse(&e, s, const_names, func1_names, funcs1, func2_names, funcs2, log_offset, log_ctx);
00532 
00533     if (ret < 0) {
00534         *d = NAN;
00535         return ret;
00536     }
00537     *d = av_expr_eval(e, const_values, opaque);
00538     av_expr_free(e);
00539     return isnan(*d) ? AVERROR(EINVAL) : 0;
00540 }
00541 
00542 #ifdef TEST
00543 #undef printf
00544 #include <string.h>
00545 
00546 static double const_values[] = {
00547     M_PI,
00548     M_E,
00549     0
00550 };
00551 
00552 static const char *const_names[] = {
00553     "PI",
00554     "E",
00555     0
00556 };
00557 
00558 int main(int argc, char **argv)
00559 {
00560     int i;
00561     double d;
00562     const char **expr, *exprs[] = {
00563         "",
00564         "1;2",
00565         "-20",
00566         "-PI",
00567         "+PI",
00568         "1+(5-2)^(3-1)+1/2+sin(PI)-max(-2.2,-3.1)",
00569         "80G/80Gi",
00570         "1k",
00571         "1Gi",
00572         "1gi",
00573         "1GiFoo",
00574         "1k+1k",
00575         "1Gi*3foo",
00576         "foo",
00577         "foo(",
00578         "foo()",
00579         "foo)",
00580         "sin",
00581         "sin(",
00582         "sin()",
00583         "sin)",
00584         "sin 10",
00585         "sin(1,2,3)",
00586         "sin(1 )",
00587         "1",
00588         "1foo",
00589         "bar + PI + E + 100f*2 + foo",
00590         "13k + 12f - foo(1, 2)",
00591         "1gi",
00592         "1Gi",
00593         "st(0, 123)",
00594         "st(1, 123); ld(1)",
00595         /* compute 1+2+...+N */
00596         "st(0, 1); while(lte(ld(0), 100), st(1, ld(1)+ld(0));st(0, ld(0)+1)); ld(1)",
00597         /* compute Fib(N) */
00598         "st(1, 1); st(2, 2); st(0, 1); while(lte(ld(0),10), st(3, ld(1)+ld(2)); st(1, ld(2)); st(2, ld(3)); st(0, ld(0)+1)); ld(3)",
00599         "while(0, 10)",
00600         "st(0, 1); while(lte(ld(0),100), st(1, ld(1)+ld(0)); st(0, ld(0)+1))",
00601         "isnan(1)",
00602         "isnan(NAN)",
00603         "floor(NAN)",
00604         "floor(123.123)",
00605         "floor(-123.123)",
00606         "trunc(123.123)",
00607         "trunc(-123.123)",
00608         "ceil(123.123)",
00609         "ceil(-123.123)",
00610         "sqrt(1764)",
00611         "isnan(sqrt(-1))",
00612         "not(1)",
00613         "not(NAN)",
00614         "not(0)",
00615         NULL
00616     };
00617 
00618     for (expr = exprs; *expr; expr++) {
00619         printf("Evaluating '%s'\n", *expr);
00620         av_expr_parse_and_eval(&d, *expr,
00621                                const_names, const_values,
00622                                NULL, NULL, NULL, NULL, NULL, 0, NULL);
00623         printf("'%s' -> %f\n\n", *expr, d);
00624     }
00625 
00626     av_expr_parse_and_eval(&d, "1+(5-2)^(3-1)+1/2+sin(PI)-max(-2.2,-3.1)",
00627                            const_names, const_values,
00628                            NULL, NULL, NULL, NULL, NULL, 0, NULL);
00629     printf("%f == 12.7\n", d);
00630     av_expr_parse_and_eval(&d, "80G/80Gi",
00631                            const_names, const_values,
00632                            NULL, NULL, NULL, NULL, NULL, 0, NULL);
00633     printf("%f == 0.931322575\n", d);
00634 
00635     if (argc > 1 && !strcmp(argv[1], "-t")) {
00636         for (i = 0; i < 1050; i++) {
00637             START_TIMER;
00638             av_expr_parse_and_eval(&d, "1+(5-2)^(3-1)+1/2+sin(PI)-max(-2.2,-3.1)",
00639                                    const_names, const_values,
00640                                    NULL, NULL, NULL, NULL, NULL, 0, NULL);
00641             STOP_TIMER("av_expr_parse_and_eval");
00642         }
00643     }
00644 
00645     return 0;
00646 }
00647 #endif
Generated on Sat Mar 17 2012 12:57:57 for Libav by doxygen 1.7.1