movtextdec.c: Add support for fontsize

Add support for fontsize in style records. The patch uses reset to
directly change back to default style instead of using closing tags,
since we are not handling the default styles right now.
Signed-off-by: Niklesh <niklesh.lalwani@iitb.ac.in>

libavcodec/movtextdec.c

@@ -39,6 +39,7 @@ typedef struct {
     uint16_t style_start;
     uint16_t style_end;
     uint8_t style_flag;
+    uint8_t fontsize;
 } StyleBox;
 
 typedef struct {
@@ -120,13 +121,14 @@ static int decode_styl(const uint8_t *tsmb, MovTextContext *m, AVPacket *avpkt)
         // fontID = AV_RB16(tsmb);
         tsmb += 2;
         m->s_temp->style_flag = AV_RB8(tsmb);
+        tsmb++;
+        m->s_temp->fontsize = AV_RB8(tsmb);
         av_dynarray_add(&m->s, &m->count_s, m->s_temp);
         if(!m->s) {
             mov_text_cleanup(m);
             return AVERROR(ENOMEM);
         }
-        // fontsize = AV_RB8(tsmb);
-        tsmb += 2;
+        tsmb++;
         // text-color-rgba
         tsmb += 4;
     }
@@ -150,12 +152,7 @@ static int text_to_ass(AVBPrint *buf, const char *text, const char *text_end,
         if (m->box_flags & STYL_BOX) {
             for (i = 0; i < m->style_entries; i++) {
                 if (m->s[i]->style_flag && text_pos == m->s[i]->style_end) {
-                    if (m->s[i]->style_flag & STYLE_FLAG_BOLD)
-                        av_bprintf(buf, "{\\b0}");
-                    if (m->s[i]->style_flag & STYLE_FLAG_ITALIC)
-                        av_bprintf(buf, "{\\i0}");
-                    if (m->s[i]->style_flag & STYLE_FLAG_UNDERLINE)
-                        av_bprintf(buf, "{\\u0}");
+                    av_bprintf(buf, "{\\r}");
                 }
             }
             for (i = 0; i < m->style_entries; i++) {
@@ -166,6 +163,7 @@ static int text_to_ass(AVBPrint *buf, const char *text, const char *text_end,
                         av_bprintf(buf, "{\\i1}");
                     if (m->s[i]->style_flag & STYLE_FLAG_UNDERLINE)
                         av_bprintf(buf, "{\\u1}");
+                    av_bprintf(buf, "{\\fs%d}", m->s[i]->fontsize);
                 }
             }
         }