[FFmpeg-cvslog] r15211 - trunk/libavformat/matroskadec.c

[aurel]

Author: aurel
Date: Fri Sep  5 01:26:12 2008
New Revision: 15211

Log:
matroskadec: fix ASS subtitle track packets before emitting them
Matroska does some butchering when storing the ASS lines. The start and end
time are removed (because they are duplicated in the container).
The matroska_fix_ass_packet() function simply restore those start and end
time in ASS lines to ensure our ASS packets comply with the ASS spec.


Modified:
   trunk/libavformat/matroskadec.c

Modified: trunk/libavformat/matroskadec.c
==============================================================================
--- trunk/libavformat/matroskadec.c	(original)
+++ trunk/libavformat/matroskadec.c	Fri Sep  5 01:26:12 2008
@@ -28,6 +28,7 @@
  * Specs available on the Matroska project page: http://www.matroska.org/.
  */
 
+#include <stdio.h>
 #include "avformat.h"
 /* For codec_get_id(). */
 #include "riff.h"
@@ -932,6 +933,37 @@ static int matroska_decode_buffer(uint8_
     return -1;
 }
 
+static void matroska_fix_ass_packet(MatroskaDemuxContext *matroska,
+                                    AVPacket *pkt)
+{
+    char *line, *layer, *ptr = pkt->data, *end = ptr+pkt->size;
+    for (; *ptr!=',' && ptr<end-1; ptr++);
+    if (*ptr == ',')
+        layer = ++ptr;
+    for (; *ptr!=',' && ptr<end-1; ptr++);
+    if (*ptr == ',') {
+        int64_t end_pts = pkt->pts + pkt->convergence_duration;
+        int sc = matroska->time_scale * pkt->pts / 10000000;
+        int ec = matroska->time_scale * end_pts  / 10000000;
+        int sh, sm, ss, eh, em, es, len;
+        sh = sc/360000;  sc -= 360000*sh;
+        sm = sc/  6000;  sc -=   6000*sm;
+        ss = sc/   100;  sc -=    100*ss;
+        eh = ec/360000;  ec -= 360000*eh;
+        em = ec/  6000;  ec -=   6000*em;
+        es = ec/   100;  ec -=    100*es;
+        *ptr++ = '\0';
+        len = 50 + end-ptr + FF_INPUT_BUFFER_PADDING_SIZE;
+        if (!(line = av_malloc(len)))
+            return;
+        snprintf(line,len,"Dialogue: %s,%d:%02d:%02d.%02d,%d:%02d:%02d.%02d,%s",
+                 layer, sh, sm, ss, sc, eh, em, es, ec, ptr);
+        av_free(pkt->data);
+        pkt->data = line;
+        pkt->size = strlen(line);
+    }
+}
+
 static void matroska_convert_tags(AVFormatContext *s, EbmlList *list)
 {
     MatroskaTag *tags = list->elem;
@@ -1588,6 +1620,9 @@ static int matroska_parse_block(Matroska
                 else
                     pkt->duration = duration;
 
+                if (st->codec->codec_id == CODEC_ID_SSA)
+                    matroska_fix_ass_packet(matroska, pkt);
+
                 dynarray_add(&matroska->packets, &matroska->num_packets, pkt);
             }