@@ -761,9 +761,10 @@ separated by ":".

 A description of the accepted options follows.

 @table @option

-@item dar

-Specifies the display aspect ratio adopted for rendering the

-subtitles. Default value is "1.0".

+@item original_size

+Specifies the size of the original video, the video for which the ASS file

+was composed. Due to a misdesign in ASS aspect ratio arithmetic, this is

+necessary to correctly scale the fonts if the aspect ratio has been changed.

 @end table

 For example, to render the file @file{sub.ass} on top of the input

@@ -30,7 +30,7 @@

 #define LIBAVFILTER_VERSION_MAJOR  2

 #define LIBAVFILTER_VERSION_MINOR 66

-#define LIBAVFILTER_VERSION_MICRO 100

+#define LIBAVFILTER_VERSION_MICRO 101

 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \

                                                LIBAVFILTER_VERSION_MINOR, \

@@ -45,14 +45,14 @@ typedef struct {

     char *filename;

     uint8_t rgba_map[4];

     int     pix_step[4];       ///< steps per pixel for each plane of the main output

-    char *dar_str;

-    AVRational dar;

+    char *original_size_str;

+    int original_w, original_h;

 } AssContext;

 #define OFFSET(x) offsetof(AssContext, x)

 static const AVOption ass_options[] = {

-    {"dar",  "set subtitles display aspect ratio", OFFSET(dar_str), AV_OPT_TYPE_STRING, {.str = "1.0"},  CHAR_MIN, CHAR_MAX },

+    {"original_size",  "set the size of the original video (used to scale fonts)", OFFSET(original_size_str), AV_OPT_TYPE_STRING, {.str = NULL},  CHAR_MIN, CHAR_MAX },

     {NULL},

 };

@@ -107,10 +107,11 @@ static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)

         return ret;

     }

-    if (av_parse_ratio(&ass->dar, ass->dar_str, 100, 0, ctx) < 0 ||

-        ass->dar.num < 0 || ass->dar.den <= 0) {

+    if (ass->original_size_str &&

+        av_parse_video_size(&ass->original_w, &ass->original_h,

+                            ass->original_size_str) < 0) {

         av_log(ctx, AV_LOG_ERROR,

-               "Invalid string '%s' or value for display aspect ratio.\n", ass->dar_str);

+               "Invalid original size '%s'.\n", ass->original_size_str);

         return AVERROR(EINVAL);

     }

@@ -136,8 +137,6 @@ static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)

     }

     ass_set_fonts(ass->renderer, NULL, NULL, 1, NULL, 1);

-

-    av_log(ctx, AV_LOG_INFO, "dar:%f\n", av_q2d(ass->dar));

     return 0;

 }

@@ -146,7 +145,7 @@ static av_cold void uninit(AVFilterContext *ctx)

     AssContext *ass = ctx->priv;

     av_freep(&ass->filename);

-    av_freep(&ass->dar_str);

+    av_freep(&ass->original_size_str);

     if (ass->track)

         ass_free_track(ass->track);

     if (ass->renderer)

@@ -173,8 +172,6 @@ static int config_input(AVFilterLink *inlink)

 {

     AssContext *ass = inlink->dst->priv;

     const AVPixFmtDescriptor *pix_desc = &av_pix_fmt_descriptors[inlink->format];

-    double sar = inlink->sample_aspect_ratio.num ?

-        av_q2d(inlink->sample_aspect_ratio) : 1;

     av_image_fill_max_pixsteps(ass->pix_step, NULL, pix_desc);

     ff_fill_rgba_map(ass->rgba_map, inlink->format);

@@ -183,7 +180,9 @@ static int config_input(AVFilterLink *inlink)

     ass->vsub = pix_desc->log2_chroma_h;

     ass_set_frame_size  (ass->renderer, inlink->w, inlink->h);

-    ass_set_aspect_ratio(ass->renderer, av_q2d(ass->dar), sar);

+    if (ass->original_w && ass->original_h)

+        ass_set_aspect_ratio(ass->renderer, (double)inlink->w / inlink->h,

+                             (double)ass->original_w / ass->original_h);

     return 0;

 }