[mythtv] PATCH: closed caption support

[Gregorio Gervasio Jr.]

        This looks pretty good.  I noticed there are two styles of
captioning:

1. rowcount set to 0; number of actual rows = 1,2,3
    - usually for movies and non-live TV series

2. rowcount set to 1,2,3; number of actual rows = 1
    - usually for news, sports, live events

The first style looks good.  The second style is harder to read
because the single line gets overwritten quickly.  I don't have a
CC-capable TV to check against right now but I think that in the
second style, text is meant to "scroll" within a box with height equal
to the specified rowcount.  I've included a patch that tries to
implement that.  (I also adjusted the rowcount in the encoder to match
the comments since that looked better but I guess it should be checked
against a real decoder.)

Index: libs/libmythtv/NuppelVideoPlayer.cpp
===================================================================
RCS file: /var/lib/cvs/MC/libs/libmythtv/NuppelVideoPlayer.cpp,v
retrieving revision 1.155
diff -u -b -r1.155 NuppelVideoPlayer.cpp
--- libs/libmythtv/NuppelVideoPlayer.cpp	24 Mar 2003 18:55:47 -0000	1.155
+++ libs/libmythtv/NuppelVideoPlayer.cpp	26 Mar 2003 10:45:58 -0000
@@ -1555,7 +1555,7 @@
             if (subtitle.clr)
             {
                 //printf ("erase displayed memory\n");
-                for (j = 0; j < 3; j++)
+                for (j = 0; j < 4; j++)
                 {
                     cclines[j] = "";
                 }
@@ -1565,7 +1565,28 @@
             if (subtitle.len)
             {
                 unsigned char *end = inpos + subtitle.len;
-                int row = 0;
+                int row;
+
+                if (subtitle.rowcount == 0)
+                {
+                    // overwrite
+                    row = 0;
+                }
+                else
+                {
+                    if (subtitle.rowcount > 4)
+                    {
+                        subtitle.rowcount = 4;
+                    }
+                    // scroll up one line
+                    for (j = 0; j < subtitle.rowcount-1; j++)
+                    {
+                        cclines[j] = cclines[j+1];
+                    }
+                    cclines[subtitle.rowcount-1] = "";
+                    row = subtitle.rowcount - 1;
+                }
+
                 while (inpos < end)
                 {
                     unsigned char *cur = inpos;
@@ -1575,23 +1596,38 @@
                         cur++;
                     *cur = 0;
 
-                    if (row < 3)
+                    if (subtitle.rowcount > 0 && row >= subtitle.rowcount)
+                    {
+                        // multi-line in scroll mode -- shouldn't happen?
+                        // scroll up again
+                        for (j = 0; j < subtitle.rowcount-1; j++)
+                        {
+                            cclines[j] = cclines[j+1];
+                        }
+                        row = subtitle.rowcount - 1;
+                    }
+                    if (row < 4)
                     {
                         cclines[row++] = QString((const char *)inpos);
                         //printf ("CC text: %s\n", inpos);
                     }
+#if 0
+                    else
+                    {
+                        printf("CC overflow:  %s\n", inpos);
+                    }
+#endif
 
                     inpos = cur + 1;
                 }
 
-                if (subtitle.rowcount != row)
+                if (subtitle.rowcount == 0)
                     subtitle.rowcount = row;
-
             }
 
             //redraw
             osd->ClearAllCCText ();
-            for (j = 0; j < subtitle.rowcount && j < 3; j++)
+            for (j = 0; j < subtitle.rowcount && j < 4; j++)
             {
                 if (cclines[j].isNull() || cclines[j].isEmpty())
                     continue;
Index: libs/libmythtv/NuppelVideoRecorder.cpp
===================================================================
RCS file: /var/lib/cvs/MC/libs/libmythtv/NuppelVideoRecorder.cpp,v
retrieving revision 1.90
diff -u -b -r1.90 NuppelVideoRecorder.cpp
--- libs/libmythtv/NuppelVideoRecorder.cpp	24 Mar 2003 18:55:47 -0000	1.90
+++ libs/libmythtv/NuppelVideoRecorder.cpp	26 Mar 2003 10:45:59 -0000
@@ -1808,13 +1808,13 @@
                            cc->ccbuf[cc->ccmode][len--] = 0;
                            break;
                        case 0x25:      //2 row caption
-                           subtitle->rowcount = 1;
+                           subtitle->rowcount = 2;
                            break;
                        case 0x26:      //3 row caption
-                           subtitle->rowcount = 2;
+                           subtitle->rowcount = 3;
                            break;
                        case 0x27:      //4 row caption
-                           subtitle->rowcount = 3;
+                           subtitle->rowcount = 4;
                            break;
                        case 0x29:      //resume direct caption
                            printf ("\nresume direct caption\n");

-- 
Gregorio Gervasio, Jr.
gtgj at pacbell.net