| Index: source/patched-ffmpeg-mt/libavfilter/vsrc_nullsrc.c | 
| =================================================================== | 
| --- source/patched-ffmpeg-mt/libavfilter/vsrc_nullsrc.c	(revision 65184) | 
| +++ source/patched-ffmpeg-mt/libavfilter/vsrc_nullsrc.c	(working copy) | 
| @@ -21,10 +21,31 @@ | 
| * null video source | 
| */ | 
|  | 
| +#include "libavutil/avstring.h" | 
| +#include "libavutil/eval.h" | 
| +#include "libavcore/parseutils.h" | 
| #include "avfilter.h" | 
|  | 
| +static const char *var_names[] = { | 
| +    "E", | 
| +    "PHI", | 
| +    "PI", | 
| +    "AVTB",   /* default timebase 1/AV_TIME_BASE */ | 
| +    NULL | 
| +}; | 
| + | 
| +enum var_name { | 
| +    VAR_E, | 
| +    VAR_PHI, | 
| +    VAR_PI, | 
| +    VAR_AVTB, | 
| +    VAR_VARS_NB | 
| +}; | 
| + | 
| typedef struct { | 
| int w, h; | 
| +    char tb_expr[256]; | 
| +    double var_values[VAR_VARS_NB]; | 
| } NullContext; | 
|  | 
| static int init(AVFilterContext *ctx, const char *args, void *opaque) | 
| @@ -33,9 +54,10 @@ | 
|  | 
| priv->w = 352; | 
| priv->h = 288; | 
| +    av_strlcpy(priv->tb_expr, "AVTB", sizeof(priv->tb_expr)); | 
|  | 
| if (args) | 
| -        sscanf(args, "%d:%d", &priv->w, &priv->h); | 
| +        sscanf(args, "%d:%d:%255[^:]", &priv->w, &priv->h, priv->tb_expr); | 
|  | 
| if (priv->w <= 0 || priv->h <= 0) { | 
| av_log(ctx, AV_LOG_ERROR, "Non-positive size values are not acceptable.\n"); | 
| @@ -47,12 +69,36 @@ | 
|  | 
| static int config_props(AVFilterLink *outlink) | 
| { | 
| -    NullContext *priv = outlink->src->priv; | 
| +    AVFilterContext *ctx = outlink->src; | 
| +    NullContext *priv = ctx->priv; | 
| +    AVRational tb; | 
| +    int ret; | 
| +    double res; | 
|  | 
| +    priv->var_values[VAR_E]    = M_E; | 
| +    priv->var_values[VAR_PHI]  = M_PHI; | 
| +    priv->var_values[VAR_PI]   = M_PI; | 
| +    priv->var_values[VAR_AVTB] = av_q2d(AV_TIME_BASE_Q); | 
| + | 
| +    if ((ret = av_parse_and_eval_expr(&res, priv->tb_expr, var_names, priv->var_values, | 
| +                                      NULL, NULL, NULL, NULL, NULL, 0, NULL)) < 0) { | 
| +        av_log(ctx, AV_LOG_ERROR, "Invalid expression '%s' for timebase.\n", priv->tb_expr); | 
| +        return ret; | 
| +    } | 
| +    tb = av_d2q(res, INT_MAX); | 
| +    if (tb.num <= 0 || tb.den <= 0) { | 
| +        av_log(ctx, AV_LOG_ERROR, | 
| +               "Invalid non-positive value for the timebase %d/%d.\n", | 
| +               tb.num, tb.den); | 
| +        return AVERROR(EINVAL); | 
| +    } | 
| + | 
| outlink->w = priv->w; | 
| outlink->h = priv->h; | 
| +    outlink->time_base = tb; | 
|  | 
| -    av_log(outlink->src, AV_LOG_INFO, "w:%d h:%d\n", priv->w, priv->h); | 
| +    av_log(outlink->src, AV_LOG_INFO, "w:%d h:%d tb:%d/%d\n", priv->w, priv->h, | 
| +           tb.num, tb.den); | 
|  | 
| return 0; | 
| } | 
|  |