lavc: switch from ts_end to duration in ff_ass_add_rect.

Make possible a end-to-presentation duration.

libavcodec/ass.c

@@ -70,15 +70,18 @@ static int ts_to_string(char *str, int strlen, int ts)
 }
 
 int ff_ass_add_rect(AVSubtitle *sub, const char *dialog,
-                    int ts_start, int ts_end, int raw)
+                    int ts_start, int duration, int raw)
 {
-    int len = 0, dlen, duration = ts_end - ts_start;
+    int len = 0, dlen;
     char s_start[16], s_end[16], header[48] = {0};
     AVSubtitleRect **rects;
 
     if (!raw) {
         ts_to_string(s_start, sizeof(s_start), ts_start);
-        ts_to_string(s_end,   sizeof(s_end),   ts_end  );
+        if (duration == -1)
+            snprintf(s_end, sizeof(s_end), "9:59:59.99");
+        else
+            ts_to_string(s_end, sizeof(s_end), ts_start + duration);
         len = snprintf(header, sizeof(header), "Dialogue: 0,%s,%s,",
                        s_start, s_end);
     }

libavcodec/ass.h

@@ -74,7 +74,8 @@ int ff_ass_subtitle_header_default(AVCodecContext *avctx);
  * @param sub pointer to the AVSubtitle
  * @param dialog ASS dialog to add to sub
  * @param ts_start start timestamp for this dialog (in 1/100 second unit)
- * @param ts_end end timestamp for this dialog (in 1/100 second unit)
+ * @param duration duration for this dialog (in 1/100 second unit), can be -1
+ *                 to last until the end of the presentation
  * @param raw when set to 1, it indicates that dialog contains a whole ASS
  *                           dialog line which should be copied as is.
  *            when set to 0, it indicates that dialog contains only the Text
@@ -85,6 +86,6 @@ int ff_ass_subtitle_header_default(AVCodecContext *avctx);
  *         A negative value indicates an error.
  */
 int ff_ass_add_rect(AVSubtitle *sub, const char *dialog,
-                    int ts_start, int ts_end, int raw);
+                    int ts_start, int duration, int raw);
 
 #endif /* AVCODEC_ASS_H */

libavcodec/jacosubdec.c

@@ -175,8 +175,6 @@ static int jacosub_decode_frame(AVCodecContext *avctx,
         goto end;
 
     if (*ptr) {
-        int ts_start = avpkt->pts;
-        int ts_end   = avpkt->pts + avpkt->duration;
         AVBPrint buffer;
         char *dec_sub;
 
@@ -188,7 +186,7 @@ static int jacosub_decode_frame(AVCodecContext *avctx,
         av_bprint_init(&buffer, JSS_MAX_LINESIZE, JSS_MAX_LINESIZE);
         jacosub_to_ass(avctx, &buffer, ptr);
         av_bprint_finalize(&buffer, &dec_sub);
-        ff_ass_add_rect(sub, dec_sub, ts_start, ts_end, 0);
+        ff_ass_add_rect(sub, dec_sub, avpkt->pts, avpkt->duration, 0);
         av_free(dec_sub);
     }
 

libavcodec/microdvddec.c

@@ -261,10 +261,6 @@ static int microdvd_decode_frame(AVCodecContext *avctx,
     char *decoded_sub;
     char *line = avpkt->data;
     char *end = avpkt->data + avpkt->size;
-    int64_t frame_start = avpkt->pts;
-    int64_t frame_end   = avpkt->pts + avpkt->duration;
-    int ts_start = av_rescale_q(frame_start, avctx->time_base, (AVRational){1,100});
-    int ts_end   = av_rescale_q(frame_end,   avctx->time_base, (AVRational){1,100});
     struct microdvd_tag tags[sizeof(MICRODVD_TAGS) - 1] = {{0}};
 
     if (avpkt->size <= 0)
@@ -299,8 +295,14 @@ static int microdvd_decode_frame(AVCodecContext *avctx,
 
 end:
     av_bprint_finalize(&new_line, &decoded_sub);
-    if (*decoded_sub)
-        ff_ass_add_rect(sub, decoded_sub, ts_start, ts_end, 0);
+    if (*decoded_sub) {
+        int64_t start    = avpkt->pts;
+        int64_t duration = avpkt->duration;
+        int ts_start     = av_rescale_q(start,    avctx->time_base, (AVRational){1,100});
+        int ts_duration  = duration != -1 ?
+                           av_rescale_q(duration, avctx->time_base, (AVRational){1,100}) : -1;
+        ff_ass_add_rect(sub, decoded_sub, ts_start, ts_duration, 0);
+    }
     av_free(decoded_sub);
 
     *got_sub_ptr = sub->num_rects > 0;

libavcodec/srtdec.c

@@ -222,7 +222,7 @@ static int srt_decode_frame(AVCodecContext *avctx,
             break;
         ptr = srt_to_ass(avctx, buffer, buffer+sizeof(buffer), ptr,
                          x1, y1, x2, y2);
-        ff_ass_add_rect(sub, buffer, ts_start, ts_end, 0);
+        ff_ass_add_rect(sub, buffer, ts_start, ts_end-ts_start, 0);
     }
 
     *got_sub_ptr = sub->num_rects > 0;