Add SSA subtitle import

1 files changed, 275 insertions, 9 deletions

diff --git a/libhb/decssasub.c b/libhb/decssasub.c
index 612c7c1c2..4bf9c79d5 100644
--- a/libhb/decssasub.c
+++ b/libhb/decssasub.c
@@ -34,10 +34,12 @@
 
 struct hb_work_private_s
 {
-    // If decoding to PICTURESUB format:
-    int readOrder;
+    hb_job_t      * job;
+    hb_subtitle_t * subtitle;
 
-    hb_job_t *job;
+    // SSA Import
+    FILE          * file;
+    int             readOrder;
 };
 
 #define SSA_VERBOSE_PACKETS 0
@@ -220,27 +222,287 @@ void hb_ssa_style_init(hb_subtitle_style_t *style)
     style->bg_alpha  = 0xFF;
 }
 
+static int extradataInit( hb_work_private_t * pv )
+{
+    int    events = 0;
+    char * events_tag = "[Events]";
+    char * format_tag = "Format:";
+    int    events_len = strlen(events_tag);;
+    int    format_len = strlen(format_tag);;
+    char * header = NULL;
+
+    while (1)
+    {
+        char   * line = NULL;
+        size_t   len, size = 0;
+
+        len = getline(&line, &size, pv->file);
+        if (len < 0)
+        {
+            // Incomplete SSA header
+            free(header);
+            return 1;
+        }
+        if (len > 0)
+        {
+            if (header != NULL)
+            {
+                char * tmp = header;
+                header = hb_strdup_printf("%s%s", header, line);
+                free(tmp);
+            }
+            else
+            {
+                header = strdup(line);
+            }
+        }
+        if (!events)
+        {
+            if (len >= events_len && !strncasecmp(line, events_tag, events_len))
+            {
+                events = 1;
+            }
+        }
+        else
+        {
+            if (len >= format_len && !strncasecmp(line, format_tag, format_len))
+            {
+                free(line);
+                break;
+            }
+            if (len > 0)
+            {
+                // Improperly formatted SSA header
+                free(header);
+                return 1;
+            }
+        }
+        free(line);
+    }
+    pv->subtitle->extradata = (uint8_t*)header;
+    pv->subtitle->extradata_size = strlen(header) + 1;
+
+    return 0;
+}
+
 static int decssaInit( hb_work_object_t * w, hb_job_t * job )
 {
     hb_work_private_t * pv;
 
     pv              = calloc( 1, sizeof( hb_work_private_t ) );
     w->private_data = pv;
-    pv->job = job;
+    pv->job         = job;
+    pv->subtitle    = w->subtitle;
+
+    if (w->fifo_in == NULL && pv->subtitle->config.src_filename != NULL)
+    {
+        pv->file = hb_fopen(pv->subtitle->config.src_filename, "r");
+        if(pv->file == NULL)
+        {
+            hb_error("Could not open the SSA subtitle file '%s'\n",
+                     pv->subtitle->config.src_filename);
+            goto fail;
+        }
+
+        // Read SSA header and store in subtitle extradata
+        if (extradataInit(pv))
+        {
+            goto fail;
+        }
+    }
+
+    return 0;
+
+fail:
+    if (pv != NULL)
+    {
+        if (pv->file != NULL)
+        {
+            fclose(pv->file);
+        }
+        free(pv);
+        w->private_data = NULL;
+    }
+    return 1;
+}
+
+#define SSA_2_HB_TIME(hr,min,sec,centi) \
+    ( 90LL * ( hr    * 1000LL * 60 * 60 +\
+              min   * 1000LL * 60 +\
+              sec   * 1000LL +\
+              centi * 10LL ) )
+
+/*
+ * Parses the start and stop time from the specified SSA packet.
+ *
+ * Returns true if parsing failed; false otherwise.
+ */
+static int parse_timing( char *line, int64_t *start, int64_t *stop )
+{
+    /*
+     * Parse Start and End fields for timing information
+     */
+    int start_hr, start_min, start_sec, start_centi;
+    int   end_hr,   end_min,   end_sec,   end_centi;
+    // SSA subtitles have an empty layer field (bare ',').  The scanf
+    // format specifier "%*128[^,]" will not match on a bare ','.  There
+    // must be at least one non ',' character in the match.  So the format
+    // specifier is placed directly next to the ':' so that the next
+    // expected ' ' after the ':' will be the character it matches on
+    // when there is no layer field.
+    int numPartsRead = sscanf( (char *) line, "Dialogue:%*128[^,],"
+        "%d:%d:%d.%d,"  // Start
+        "%d:%d:%d.%d,", // End
+        &start_hr, &start_min, &start_sec, &start_centi,
+          &end_hr,   &end_min,   &end_sec,   &end_centi );
+    if ( numPartsRead != 8 )
+        return 1;
+
+    *start = SSA_2_HB_TIME(start_hr, start_min, start_sec, start_centi);
+    *stop  = SSA_2_HB_TIME(  end_hr,   end_min,   end_sec,   end_centi);
 
     return 0;
 }
 
+static char * find_field( char * pos, char * end, int fieldNum )
+{
+    int curFieldID = 1;
+    while (pos < end)
+    {
+        if ( *pos++ == ',' )
+        {
+            curFieldID++;
+            if ( curFieldID == fieldNum )
+                return pos;
+        }
+    }
+    return NULL;
+}
+
+/*
+ * SSA line format:
+ *   Dialogue: Marked,Start,End,Style,Name,MarginL,MarginR,MarginV,Effect,Text '\0'
+ *             1      2     3   4     5    6       7       8       9      10
+ *
+ * MKV-SSA packet format:
+ *   ReadOrder,Marked,          Style,Name,MarginL,MarginR,MarginV,Effect,Text '\0'
+ *   1         2                3     4    5       6       7       8      9
+ */
+static hb_buffer_t *
+decode_line_to_mkv_ssa( hb_work_private_t * pv, char * line, int size )
+{
+    hb_buffer_t * out;
+
+    int64_t start, stop;
+    if (parse_timing(line, &start, &stop))
+    {
+        goto fail;
+    }
+
+    // Convert the SSA packet to MKV-SSA format, which is what libass expects
+    char * mkvSSA;
+    int    numPartsRead;
+    char * styleToTextFields;
+    char * layerField = malloc(size);
+
+    // SSA subtitles have an empty layer field (bare ',').  The scanf
+    // format specifier "%*128[^,]" will not match on a bare ','.  There
+    // must be at least one non ',' character in the match.  So the format
+    // specifier is placed directly next to the ':' so that the next
+    // expected ' ' after the ':' will be the character it matches on
+    // when there is no layer field.
+    numPartsRead = sscanf( (char *)line, "Dialogue:%128[^,],", layerField );
+    if ( numPartsRead != 1 )
+    {
+        free(layerField);
+        goto fail;
+    }
+
+    styleToTextFields = find_field( line, line + size, 4 );
+    if ( styleToTextFields == NULL ) {
+        free( layerField );
+        goto fail;
+    }
+
+    // The sscanf conversion above will result in an extra space
+    // before the layerField.  Strip the space.
+    char *stripLayerField = layerField;
+    for(; *stripLayerField == ' '; stripLayerField++);
+
+    out = hb_buffer_init( size + 1 );
+    mkvSSA = (char*)out->data;
+
+    mkvSSA[0] = '\0';
+    sprintf(mkvSSA, "%d", pv->readOrder++);
+    strcat( mkvSSA, "," );
+    strcat( mkvSSA, stripLayerField );
+    strcat( mkvSSA, "," );
+    strcat( mkvSSA, (char *)styleToTextFields );
+
+    out->size           = strlen(mkvSSA) + 1;
+    out->s.frametype    = HB_FRAME_SUBTITLE;
+    out->s.start        = start;
+    out->s.duration     = stop - start;
+    out->s.stop         = stop;
+
+    if( out->size == 0 )
+    {
+        hb_buffer_close(&out);
+    }
+
+    free( layerField );
+
+    return out;
+
+fail:
+    hb_log( "decssasub: malformed SSA subtitle packet: %.*s\n", size, line );
+    return NULL;
+}
+
+/*
+ * Read the SSA file and put the entries into the subtitle fifo for all to read
+ */
+static hb_buffer_t * ssa_read( hb_work_private_t * pv )
+{
+    hb_buffer_t * out;
+
+    while (!feof(pv->file))
+    {
+        char   * line = NULL;
+        size_t   len, size = 0;
+
+        len = getline(&line, &size, pv->file);
+        if (len > 0)
+        {
+            out = decode_line_to_mkv_ssa(pv, line, len);
+            if (out != NULL)
+            {
+                return out;
+            }
+        }
+        if (len < 0)
+        {
+            // Error or EOF
+            out = hb_buffer_eof_init();
+            return out;
+        }
+    }
+    out = hb_buffer_eof_init();
+
+    return out;
+}
+
 static int decssaWork( hb_work_object_t * w, hb_buffer_t ** buf_in,
                         hb_buffer_t ** buf_out )
 {
-    hb_buffer_t * in = *buf_in;
-
-#if SSA_VERBOSE_PACKETS
-    printf("\nPACKET(%"PRId64",%"PRId64"): %.*s\n", in->s.start/90, in->s.stop/90, in->size, in->data);
-#endif
+    hb_work_private_t * pv =  w->private_data;
+    hb_buffer_t       * in = *buf_in;
 
     *buf_in = NULL;
+    if (in == NULL && pv->file != NULL)
+    {
+        in = ssa_read(pv);
+    }
     *buf_out = in;
     if (in->s.flags & HB_BUF_FLAG_EOF)
     {
@@ -254,6 +516,10 @@ static int decssaWork( hb_work_object_t * w, hb_buffer_t ** buf_in,
     hb_buffer_realloc(in, ++in->size);
     in->data[in->size - 1] = '\0';
 
+#if SSA_VERBOSE_PACKETS
+    printf("\nPACKET(%"PRId64",%"PRId64"): %.*s\n", in->s.start/90, in->s.stop/90, in->size, in->data);
+#endif
+
     return HB_WORK_OK;
 }