[MPlayer-dev-eng] Subtitle timing correction

[Adam Tlałka]

Welcome,

I found that subreader.c:adjust_subs_time() works incorrectly in some cases.
It should check if sub_uses_time is set and then calculate time
of single frame to correct overlapping subtitles timings.
Patch attached.

Regards  
-- 
Adam Tlałka       mailto:atlka at pg.gda.pl    ^v^ ^v^ ^v^
PGP public key:   finger atlka at sunrise.pg.gda.pl
-------------- next part --------------
--- ../main_dist/subreader.c	2006-05-13 07:52:53.000000000 +0200
+++ subreader.c	2006-05-13 08:07:04.000000000 +0200
@@ -1241,39 +1241,42 @@
 
 static void adjust_subs_time(subtitle* sub, float subtime, float fps, int block,
                              int sub_num, int sub_uses_time) {
-	int n,m;
+	int i,j,n,m;
 	subtitle* nextsub;
-	int i = sub_num;
 	unsigned long subfms = (sub_uses_time ? 100 : fps) * subtime;
+	unsigned long substep = (sub_uses_time ? 100 / fps + 1 : 1); // ~1 frame
 	unsigned long overlap = (sub_uses_time ? 100 : fps) / 5; // 0.2s
 	
 	n=m=0;
+	i=j=sub_num;
 	if (i)	for (;;){
 		if (sub->end <= sub->start){
 			sub->end = sub->start + subfms;
 			m++;
 			n++;
+	mp_msg(MSGT_SUBREADER,MSGL_V,"SUB: %d: end time corrected .\n",j-i+1);
 		}
 		if (!--i) break;
 		nextsub = sub + 1;
-	    if(block){
-		if ((sub->end > nextsub->start) && (sub->end <= nextsub->start + overlap)) {
-		    // these subtitles overlap for less than 0.2 seconds
-		    // and would result in very short overlapping subtitle
-		    // so let's fix the problem here, before overlapping code
-		    // get its hands on them
-		    unsigned delta = sub->end - nextsub->start, half = delta / 2;
-		    sub->end -= half + 1;
-		    nextsub->start += delta - half;
-		}
 		if (sub->end >= nextsub->start){
-			sub->end = nextsub->start - 1;
-			if (sub->end - sub->start > subfms)
-				sub->end = sub->start + subfms;
-			if (!m)
-				n++;
-		}
-	    }
+			if (block){
+				sub->end = nextsub->start - substep;
+				if (sub->end - sub->start > subfms)
+					sub->end = sub->start + subfms;
+				if (!m)
+ 					n++;
+	mp_msg(MSGT_SUBREADER,MSGL_V,"SUB: %d: overlapping removed.\n",j-i);
+			} else if (sub->end <= nextsub->start + overlap){
+			// these subtitles overlap for less than 0.2 seconds
+		    	// and would result in very short overlapping subtitle
+			// so let's fix the problem here, before overlapping code
+			// get its hands on them
+				sub->end = nextsub->start + overlap + substep;
+				if (!m)
+ 					n++;
+	mp_msg(MSGT_SUBREADER,MSGL_V,"SUB: %d: overlapping corrected.\n",j-i);
+			}
+	    	}
 
 		/* Theory:
 		 * Movies are often converted from FILM (24 fps)
@@ -1508,7 +1511,7 @@
 	return NULL;
     }
 
-    // we do overlap if the user forced it (suboverlap_enable == 2) or
+    // we do overlap if the user forced it (suboverlap_enabled == 2) or
     // the user didn't forced no-overlapsub and the format is Jacosub or Ssa.
     // this is because usually overlapping subtitles are found in these formats,
     // while in others they are probably result of bad timing
@@ -1715,7 +1718,7 @@
     free(first);
 
     return_sub = second;
-} else { //if(suboverlap_enabled)
+} else { // we do not overlap subtitles
     adjust_subs_time(first, 6.0, fps, 1, sub_num, uses_time);/*~6 secs AST*/
     return_sub = first;
 }