lavu/eval: add clip function

This commit is contained in:
Stefano Sabatini 2014-07-04 14:13:11 +02:00
parent 7cd6d61da5
commit f3e886c7df
4 changed files with 26 additions and 2 deletions

View File

@ -782,6 +782,9 @@ large numbers (usually 2^53 and larger).
Round the value of expression @var{expr} upwards to the nearest
integer. For example, "ceil(1.5)" is "2.0".
@item clip(x, min, max)
Return the value of @var{x} clipped between @var{min} and @var{max}.
@item cos(x)
Compute cosine of @var{x}.

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@ -147,7 +147,7 @@ struct AVExpr {
e_pow, e_mul, e_div, e_add,
e_last, e_st, e_while, e_taylor, e_root, e_floor, e_ceil, e_trunc,
e_sqrt, e_not, e_random, e_hypot, e_gcd,
e_if, e_ifnot, e_print, e_bitand, e_bitor, e_between,
e_if, e_ifnot, e_print, e_bitand, e_bitor, e_between, e_clip
} type;
double value; // is sign in other types
union {
@ -187,6 +187,13 @@ static double eval_expr(Parser *p, AVExpr *e)
e->param[2] ? eval_expr(p, e->param[2]) : 0);
case e_ifnot: return e->value * (!eval_expr(p, e->param[0]) ? eval_expr(p, e->param[1]) :
e->param[2] ? eval_expr(p, e->param[2]) : 0);
case e_clip: {
double x = eval_expr(p, e->param[0]);
double min = eval_expr(p, e->param[1]), max = eval_expr(p, e->param[2]);
if (isnan(min) || isnan(max) || isnan(x) || min > max)
return NAN;
return e->value * av_clipd(eval_expr(p, e->param[0]), min, max);
}
case e_between: {
double d = eval_expr(p, e->param[0]);
return e->value * (d >= eval_expr(p, e->param[1]) &&
@ -436,6 +443,7 @@ static int parse_primary(AVExpr **e, Parser *p)
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 {
for (i=0; p->func1_names && p->func1_names[i]; i++) {
if (strmatch(next, p->func1_names[i])) {
@ -632,6 +640,7 @@ static int verify_expr(AVExpr *e)
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:
return verify_expr(e->param[0]) &&
verify_expr(e->param[1]) &&
verify_expr(e->param[2]);
@ -831,6 +840,9 @@ int main(int argc, char **argv)
"between(10, -3, 10)",
"between(-4, -2, -1)",
"between(1,2)",
"clip(0, 2, 1)",
"clip(0/0, 1, 2)",
"clip(0, 0/0, 1)",
NULL
};

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@ -57,7 +57,7 @@
#define LIBAVUTIL_VERSION_MAJOR 52
#define LIBAVUTIL_VERSION_MINOR 92
#define LIBAVUTIL_VERSION_MICRO 100
#define LIBAVUTIL_VERSION_MICRO 101
#define LIBAVUTIL_VERSION_INT AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \
LIBAVUTIL_VERSION_MINOR, \

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@ -268,5 +268,14 @@ Evaluating 'between(-4, -2, -1)'
Evaluating 'between(1,2)'
'between(1,2)' -> nan
Evaluating 'clip(0, 2, 1)'
'clip(0, 2, 1)' -> nan
Evaluating 'clip(0/0, 1, 2)'
'clip(0/0, 1, 2)' -> nan
Evaluating 'clip(0, 0/0, 1)'
'clip(0, 0/0, 1)' -> nan
12.700000 == 12.7
0.931323 == 0.931322575