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new optimized eval method, by seperating parsing and runtime

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Originally committed as revision 6803 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Oded Shimon 2006-10-27 16:42:16 +00:00
parent 18de0b81d5
commit 85b4eb08cc
2 changed files with 211 additions and 73 deletions
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276
libavcodec/eval.c
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@ -30,6 +30,7 @@
#include "avcodec.h" #include "avcodec.h"
#include "mpegvideo.h" #include "mpegvideo.h"
#include "eval.h"
#include <stdio.h> #include <stdio.h>
#include <stdlib.h> #include <stdlib.h>
@ -57,8 +58,6 @@ typedef struct Parser{
char **error; char **error;
} Parser; } Parser;
static double evalExpression(Parser *p);
static int8_t si_prefixes['z' - 'E' + 1]={ static int8_t si_prefixes['z' - 'E' + 1]={
['y'-'E']= -24, ['y'-'E']= -24,
['z'-'E']= -21, ['z'-'E']= -21,
@ -126,23 +125,82 @@ static int strmatch(const char *s, const char *prefix){
return 1; return 1;
} }
static double evalPrimary(Parser *p){ struct ff_expr_s {
double d, d2=NAN; enum {
e_value, e_const, e_func0, e_func1, e_func2,
e_squish, e_gauss,
e_mod, e_max, e_min, e_eq, e_gt, e_gte,
e_pow, e_mul, e_div, e_add,
} type;
double value; // is sign in other types
union {
int const_index;
double (*func0)(double);
double (*func1)(void *, double);
double (*func2)(void *, double, double);
} a;
AVEvalExpr * param[2];
};
static double eval_expr(Parser * p, AVEvalExpr * e) {
switch (e->type) {
case e_value: return e->value;
case e_const: return e->value * p->const_value[e->a.const_index];
case e_func0: return e->value * e->a.func0(eval_expr(p, e->param[0]));
case e_func1: return e->value * e->a.func1(p->opaque, eval_expr(p, e->param[0]));
case e_func2: return e->value * e->a.func2(p->opaque, eval_expr(p, e->param[0]), eval_expr(p, e->param[1]));
case e_squish: return 1/(1+exp(4*eval_expr(p, e->param[0])));
case e_gauss: { double d = eval_expr(p, e->param[0]); return exp(-d*d/2)/sqrt(2*M_PI); }
default: {
double d = eval_expr(p, e->param[0]);
double d2 = eval_expr(p, e->param[1]);
switch (e->type) {
case e_mod: return e->value * (d - floor(d/d2)*d2);
case e_max: return e->value * (d > d2 ? d : d2);
case e_min: return e->value * (d < d2 ? d : d2);
case e_eq: return e->value * (d == d2 ? 1.0 : 0.0);
case e_gt: return e->value * (d > d2 ? 1.0 : 0.0);
case e_gte: return e->value * (d >= d2 ? 1.0 : 0.0);
case e_pow: return e->value * pow(d, d2);
case e_mul: return e->value * (d * d2);
case e_div: return e->value * (d / d2);
case e_add: return e->value * (d + d2);
}
}
}
return NAN;
}
static AVEvalExpr * parse_expr(Parser *p);
void ff_eval_free(AVEvalExpr * e) {
if (!e) return;
ff_eval_free(e->param[0]);
ff_eval_free(e->param[1]);
av_freep(&e);
}
static AVEvalExpr * parse_primary(Parser *p) {
AVEvalExpr * d = av_mallocz(sizeof(AVEvalExpr));
char *next= p->s; char *next= p->s;
int i; int i;
/* number */ /* number */
d= av_strtod(p->s, &next); d->value = av_strtod(p->s, &next);
if(next != p->s){ if(next != p->s){
d->type = e_value;
p->s= next; p->s= next;
return d; return d;
} }
d->value = 1;
/* named constants */ /* named constants */
for(i=0; p->const_name && p->const_name[i]; i++){ for(i=0; p->const_name && p->const_name[i]; i++){
if(strmatch(p->s, p->const_name[i])){ if(strmatch(p->s, p->const_name[i])){
p->s+= strlen(p->const_name[i]); p->s+= strlen(p->const_name[i]);
return p->const_value[i]; d->type = e_const;
d->a.const_index = i;
return d;
} }
} }
@ -150,126 +208,198 @@ static double evalPrimary(Parser *p){
if(p->s==NULL){ if(p->s==NULL){
*p->error = "missing ("; *p->error = "missing (";
p->s= next; p->s= next;
return NAN; ff_eval_free(d);
return NULL;
} }
p->s++; // "(" p->s++; // "("
d= evalExpression(p); if (*next == '(') { // special case do-nothing
av_freep(&d);
d = parse_expr(p);
if(p->s[0] != ')'){
*p->error = "missing )";
ff_eval_free(d);
return NULL;
}
p->s++; // ")"
return d;
}
d->param[0] = parse_expr(p);
if(p->s[0]== ','){ if(p->s[0]== ','){
p->s++; // "," p->s++; // ","
d2= evalExpression(p); d->param[1] = parse_expr(p);
} }
if(p->s[0] != ')'){ if(p->s[0] != ')'){
*p->error = "missing )"; *p->error = "missing )";
return NAN; ff_eval_free(d);
return NULL;
} }
p->s++; // ")" p->s++; // ")"
if( strmatch(next, "sinh" ) ) d= sinh(d); d->type = e_func0;
else if( strmatch(next, "cosh" ) ) d= cosh(d); if( strmatch(next, "sinh" ) ) d->a.func0 = sinh;
else if( strmatch(next, "tanh" ) ) d= tanh(d); else if( strmatch(next, "cosh" ) ) d->a.func0 = cosh;
else if( strmatch(next, "sin" ) ) d= sin(d); else if( strmatch(next, "tanh" ) ) d->a.func0 = tanh;
else if( strmatch(next, "cos" ) ) d= cos(d); else if( strmatch(next, "sin" ) ) d->a.func0 = sin;
else if( strmatch(next, "tan" ) ) d= tan(d); else if( strmatch(next, "cos" ) ) d->a.func0 = cos;
else if( strmatch(next, "atan" ) ) d= atan(d); else if( strmatch(next, "tan" ) ) d->a.func0 = tan;
else if( strmatch(next, "asin" ) ) d= asin(d); else if( strmatch(next, "atan" ) ) d->a.func0 = atan;
else if( strmatch(next, "acos" ) ) d= acos(d); else if( strmatch(next, "asin" ) ) d->a.func0 = asin;
else if( strmatch(next, "exp" ) ) d= exp(d); else if( strmatch(next, "acos" ) ) d->a.func0 = acos;
else if( strmatch(next, "log" ) ) d= log(d); else if( strmatch(next, "exp" ) ) d->a.func0 = exp;
else if( strmatch(next, "squish") ) d= 1/(1+exp(4*d)); else if( strmatch(next, "log" ) ) d->a.func0 = log;
else if( strmatch(next, "gauss" ) ) d= exp(-d*d/2)/sqrt(2*M_PI); else if( strmatch(next, "abs" ) ) d->a.func0 = fabs;
else if( strmatch(next, "abs" ) ) d= fabs(d); else if( strmatch(next, "squish") ) d->type = e_squish;
else if( strmatch(next, "mod" ) ) d-= floor(d/d2)*d2; else if( strmatch(next, "gauss" ) ) d->type = e_gauss;
else if( strmatch(next, "max" ) ) d= d > d2 ? d : d2; else if( strmatch(next, "mod" ) ) d->type = e_mod;
else if( strmatch(next, "min" ) ) d= d < d2 ? d : d2; else if( strmatch(next, "max" ) ) d->type = e_max;
else if( strmatch(next, "gt" ) ) d= d > d2 ? 1.0 : 0.0; else if( strmatch(next, "min" ) ) d->type = e_min;
else if( strmatch(next, "gte" ) ) d= d >= d2 ? 1.0 : 0.0; else if( strmatch(next, "eq" ) ) d->type = e_eq;
else if( strmatch(next, "lt" ) ) d= d > d2 ? 0.0 : 1.0; else if( strmatch(next, "gt" ) ) d->type = e_gt;
else if( strmatch(next, "lte" ) ) d= d >= d2 ? 0.0 : 1.0; else if( strmatch(next, "gte" ) ) d->type = e_gte;
else if( strmatch(next, "eq" ) ) d= d == d2 ? 1.0 : 0.0; else if( strmatch(next, "lt" ) ) { AVEvalExpr * tmp = d->param[1]; d->param[1] = d->param[0]; d->param[0] = tmp; d->type = e_gte; }
else if( strmatch(next, "(" ) ) d= d; else if( strmatch(next, "lte" ) ) { AVEvalExpr * tmp = d->param[1]; d->param[1] = d->param[0]; d->param[0] = tmp; d->type = e_gt; }
// else if( strmatch(next, "l1" ) ) d= 1 + d2*(d - 1); else {
// else if( strmatch(next, "sq01" ) ) d= (d >= 0.0 && d <=1.0) ? 1.0 : 0.0;
else{
for(i=0; p->func1_name && p->func1_name[i]; i++){ for(i=0; p->func1_name && p->func1_name[i]; i++){
if(strmatch(next, p->func1_name[i])){ if(strmatch(next, p->func1_name[i])){
return p->func1[i](p->opaque, d); d->a.func1 = p->func1[i];
d->type = e_func1;
return d;
} }
} }
for(i=0; p->func2_name && p->func2_name[i]; i++){ for(i=0; p->func2_name && p->func2_name[i]; i++){
if(strmatch(next, p->func2_name[i])){ if(strmatch(next, p->func2_name[i])){
return p->func2[i](p->opaque, d, d2); d->a.func2 = p->func2[i];
d->type = e_func2;
return d;
} }
} }
*p->error = "unknown function"; *p->error = "unknown function";
return NAN; ff_eval_free(d);
return NULL;
} }
return d; return d;
} }
static double evalPow(Parser *p, int *sign){ static AVEvalExpr * parse_pow(Parser *p, int *sign){
*sign= (*p->s == '+') - (*p->s == '-'); *sign= (*p->s == '+') - (*p->s == '-');
p->s += *sign&1; p->s += *sign&1;
return evalPrimary(p); return parse_primary(p);
} }
static double evalFactor(Parser *p){ static AVEvalExpr * parse_factor(Parser *p){
int sign, sign2; int sign, sign2;
double ret, e; AVEvalExpr * e = parse_pow(p, &sign);
ret= evalPow(p, &sign);
while(p->s[0]=='^'){ while(p->s[0]=='^'){
AVEvalExpr * tmp = av_mallocz(sizeof(AVEvalExpr));
p->s++; p->s++;
e= evalPow(p, &sign2);
ret= pow(ret, (sign2|1) * e); tmp->type = e_pow;
tmp->value = 1.;
tmp->param[0] = e;
tmp->param[1] = parse_pow(p, &sign2);
if (tmp->param[1]) tmp->param[1]->value *= (sign2|1);
e = tmp;
} }
return (sign|1) * ret; if (e) e->value *= (sign|1);
return e;
} }
static double evalTerm(Parser *p){ static AVEvalExpr * parse_term(Parser *p){
double ret= evalFactor(p); AVEvalExpr * e = parse_factor(p);
while(p->s[0]=='*' || p->s[0]=='/'){ while(p->s[0]=='*' || p->s[0]=='/'){
if(*p->s++ == '*') ret*= evalFactor(p); AVEvalExpr * tmp = av_mallocz(sizeof(AVEvalExpr));
else ret/= evalFactor(p); if(*p->s++ == '*') tmp->type = e_mul;
else tmp->type = e_div;
tmp->value = 1.;
tmp->param[0] = e;
tmp->param[1] = parse_factor(p);
e = tmp;
} }
return ret; return e;
} }
static double evalExpression(Parser *p){ static AVEvalExpr * parse_expr(Parser *p) {
double ret= 0; AVEvalExpr * e;
if(p->stack_index <= 0) //protect against stack overflows if(p->stack_index <= 0) //protect against stack overflows
return NAN; return NULL;
p->stack_index--; p->stack_index--;
do{ e = parse_term(p);
ret += evalTerm(p);
}while(*p->s == '+' || *p->s == '-'); while(*p->s == '+' || *p->s == '-') {
AVEvalExpr * tmp = av_mallocz(sizeof(AVEvalExpr));
tmp->type = e_add;
tmp->value = 1.;
tmp->param[0] = e;
tmp->param[1] = parse_term(p);
e = tmp;
};
p->stack_index++; p->stack_index++;
return ret; return e;
}
static int verify_expr(AVEvalExpr * 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_gauss: return verify_expr(e->param[0]);
default: return verify_expr(e->param[0]) && verify_expr(e->param[1]);
}
}
AVEvalExpr * ff_parse(char *s, const char **const_name,
double (**func1)(void *, double), const char **func1_name,
double (**func2)(void *, double, double), char **func2_name,
char **error){
Parser p;
AVEvalExpr * e;
p.stack_index=100;
p.s= s;
p.const_name = const_name;
p.func1 = func1;
p.func1_name = func1_name;
p.func2 = func2;
p.func2_name = func2_name;
p.error= error;
e = parse_expr(&p);
if (!verify_expr(e)) {
ff_eval_free(e);
return NULL;
}
return e;
}
double ff_parse_eval(AVEvalExpr * e, double *const_value, void *opaque) {
Parser p;
p.const_value= const_value;
p.opaque = opaque;
return eval_expr(&p, e);
} }
double ff_eval2(char *s, double *const_value, const char **const_name, double ff_eval2(char *s, double *const_value, const char **const_name,
double (**func1)(void *, double), const char **func1_name, double (**func1)(void *, double), const char **func1_name,
double (**func2)(void *, double, double), char **func2_name, double (**func2)(void *, double, double), char **func2_name,
void *opaque, char **error){ void *opaque, char **error){
Parser p; AVEvalExpr * e = ff_parse(s, const_name, func1, func1_name, func2, func2_name, error);
double d;
p.stack_index=100; if (!e) return NAN;
p.s= s; d = ff_parse_eval(e, const_value, opaque);
p.const_value= const_value; ff_eval_free(e);
p.const_name = const_name; return d;
p.func1 = func1;
p.func1_name = func1_name;
p.func2 = func2;
p.func2_name = func2_name;
p.opaque = opaque;
p.error= error;
return evalExpression(&p);
} }
#if LIBAVCODEC_VERSION_INT < ((52<<16)+(0<<8)+0) #if LIBAVCODEC_VERSION_INT < ((52<<16)+(0<<8)+0)

8
libavcodec/eval.h
View File

@ -39,4 +39,12 @@ double ff_eval2(char *s, double *const_value, const char **const_name,
double (**func2)(void *, double, double), char **func2_name, double (**func2)(void *, double, double), char **func2_name,
void *opaque, char **error); void *opaque, char **error);
typedef struct ff_expr_s AVEvalExpr;
AVEvalExpr * ff_parse(char *s, const char **const_name,
double (**func1)(void *, double), const char **func1_name,
double (**func2)(void *, double, double), char **func2_name,
char **error);
double ff_parse_eval(AVEvalExpr * e, double *const_value, void *opaque);
void ff_eval_free(AVEvalExpr * e);
#endif /* AVCODEC_EVAL_H */ #endif /* AVCODEC_EVAL_H */