Write one TTI block per subtitle line for binary STL.

This has a number of apparent advantages.  Mainly, it increases
the amount of text we can cope with in a single subtitle; before
any subtitle with a total length of 111 characters would be truncated
(and truncated wrongly, incidentally).

Also it simplifies the code for putting different lines in their
correct positions and allows individual lines to have different
horizontal position references.

diff --git a/src/stl_binary_writer.cc b/src/stl_binary_writer.cc
index baed8d80cc0714b81e14870c99509d18a0c2f384..993198588c81931cafd4e5bc9d203ad8b959d5c2 100644 (file)
--- a/src/stl_binary_writer.cc
+++ b/src/stl_binary_writer.cc
@@ -170,10 +170,9 @@ sub::write_stl_binary (
        ofstream output (file_name.string().c_str ());
        STLBinaryTables tables;
 
-       /* Find the longest subtitle in characters */
-
+       /* Find the longest subtitle in characters and count the number of lines we have */
        int longest = 0;
-
+       int lines = 0;
        BOOST_FOREACH (Subtitle const& i, subtitles) {
                BOOST_FOREACH (Line const& j, i.lines) {
                        int t = 0;
@@ -181,6 +180,7 @@ sub::write_stl_binary (
                                t += k.text.size ();
                        }
                        longest = std::max (longest, t);
+                       ++lines;
                }
        }
 
@@ -205,7 +205,7 @@ sub::write_stl_binary (
        put_string (buffer + 230, revision_date);
        put_int_as_string (buffer + 236, revision_number, 2);
        /* TTI blocks */
-       put_int_as_string (buffer + 238, subtitles.size(), 5);
+       put_int_as_string (buffer + 238, lines, 5);
        /* Total number of subtitles */
        put_int_as_string (buffer + 243, subtitles.size(), 5);
        /* Total number of subtitle groups */
@@ -233,76 +233,53 @@ sub::write_stl_binary (
 
        BOOST_FOREACH (Subtitle const& i, subtitles) {
 
-               /* Find the top vertical position of this subtitle */
-               optional<int> top;
-               BOOST_FOREACH (Line const& j, i.lines) {
-                       int const vp = vertical_position (j);
-                       if (!top || vp < top.get ()) {
-                               top = vp;
-                       }
-               }
-
-               memset (buffer, 0, 128);
-
-               /* XXX: these should increment, surely! */
-               /* Subtitle group number */
-               put_int_as_int (buffer + 0, 1, 1);
-               /* Subtitle number */
-               put_int_as_int (buffer + 1, 0, 2);
-               /* Extension block number.  Use 0xff here to indicate that it is the last TTI
-                  block in this subtitle "set", as we only ever use one.
-               */
-               put_int_as_int (buffer + 3, 255, 1);
-               /* Cumulative status */
-               put_int_as_int (buffer + 4, tables.cumulative_status_enum_to_file (CUMULATIVE_STATUS_NOT_CUMULATIVE), 1);
-               /* Time code in */
-               put_int_as_int (buffer + 5, i.from.hours(), 1);
-               put_int_as_int (buffer + 6, i.from.minutes(), 1);
-               put_int_as_int (buffer + 7, i.from.seconds(), 1);
-               put_int_as_int (buffer + 8, i.from.frames_at(sub::Rational(frames_per_second * 1000, 1000)), 1);
-               /* Time code out */
-               put_int_as_int (buffer + 9, i.to.hours(), 1);
-               put_int_as_int (buffer + 10, i.to.minutes(), 1);
-               put_int_as_int (buffer + 11, i.to.seconds(), 1);
-               put_int_as_int (buffer + 12, i.to.frames_at(sub::Rational(frames_per_second * 1000, 1000)), 1);
-               /* Vertical position */
-               put_int_as_int (buffer + 13, top.get(), 1);
-
-               /* Justification code */
-               /* XXX: this assumes the first line has the right value */
-               switch (i.lines.front().horizontal_position.reference) {
-               case LEFT_OF_SCREEN:
-                       put_int_as_int (buffer + 14, tables.justification_enum_to_file (JUSTIFICATION_LEFT), 1);
-                       break;
-               case HORIZONTAL_CENTRE_OF_SCREEN:
-                       put_int_as_int (buffer + 14, tables.justification_enum_to_file (JUSTIFICATION_CENTRE), 1);
-                       break;
-               case RIGHT_OF_SCREEN:
-                       put_int_as_int (buffer + 14, tables.justification_enum_to_file (JUSTIFICATION_RIGHT), 1);
-                       break;
-               }
-
-               /* Comment flag */
-               put_int_as_int (buffer + 15, tables.comment_enum_to_file (COMMENT_NO), 1);
-
-               /* Text */
-               string text;
-               bool italic = false;
-               bool underline = false;
-               optional<int> last_vp;
-
+               size_t line = 0;
                BOOST_FOREACH (Line const& j, i.lines) {
 
-                       /* CR/LF down to this line */
-                       int const vp = vertical_position (j);
-
-                       if (last_vp) {
-                               for (int k = last_vp.get(); k < vp; ++k) {
-                                       text += "\x8A";
-                               }
+                       memset (buffer, 0, 128);
+
+                       /* XXX: these should increment, surely! */
+                       /* Subtitle group number */
+                       put_int_as_int (buffer + 0, 1, 1);
+                       /* Subtitle number */
+                       put_int_as_int (buffer + 1, 0, 2);
+                       /* Extension block number.  These are indexed from zero except the last one is 255 */
+                       put_int_as_int (buffer + 3, line == (i.lines.size() - 1) ? 255 : line, 1);
+                       /* Cumulative status */
+                       put_int_as_int (buffer + 4, tables.cumulative_status_enum_to_file (CUMULATIVE_STATUS_NOT_CUMULATIVE), 1);
+                       /* Time code in */
+                       put_int_as_int (buffer + 5, i.from.hours(), 1);
+                       put_int_as_int (buffer + 6, i.from.minutes(), 1);
+                       put_int_as_int (buffer + 7, i.from.seconds(), 1);
+                       put_int_as_int (buffer + 8, i.from.frames_at(sub::Rational(frames_per_second * 1000, 1000)), 1);
+                       /* Time code out */
+                       put_int_as_int (buffer + 9, i.to.hours(), 1);
+                       put_int_as_int (buffer + 10, i.to.minutes(), 1);
+                       put_int_as_int (buffer + 11, i.to.seconds(), 1);
+                       put_int_as_int (buffer + 12, i.to.frames_at(sub::Rational(frames_per_second * 1000, 1000)), 1);
+                       /* Vertical position */
+                       put_int_as_int (buffer + 13, vertical_position(j), 1);
+
+                       /* Justification code */
+                       switch (j.horizontal_position.reference) {
+                       case LEFT_OF_SCREEN:
+                               put_int_as_int (buffer + 14, tables.justification_enum_to_file (JUSTIFICATION_LEFT), 1);
+                               break;
+                       case HORIZONTAL_CENTRE_OF_SCREEN:
+                               put_int_as_int (buffer + 14, tables.justification_enum_to_file (JUSTIFICATION_CENTRE), 1);
+                               break;
+                       case RIGHT_OF_SCREEN:
+                               put_int_as_int (buffer + 14, tables.justification_enum_to_file (JUSTIFICATION_RIGHT), 1);
+                               break;
                        }
 
-                       last_vp = vp;
+                       /* Comment flag */
+                       put_int_as_int (buffer + 15, tables.comment_enum_to_file (COMMENT_NO), 1);
+
+                       /* Text */
+                       string text;
+                       bool italic = false;
+                       bool underline = false;
 
                        BOOST_FOREACH (Block const& k, j.blocks) {
                                if (k.underline && !underline) {
@@ -322,28 +299,29 @@ sub::write_stl_binary (
 
                                text += utf16_to_iso6937 (utf_to_utf<wchar_t> (k.text));
                        }
-               }
 
-               /* Turn italic/underline off before the end of this subtitle */
+                       /* Turn italic/underline off before the end of this subtitle */
 
-               if (underline) {
-                       text += "\x83";
-               }
+                       if (underline) {
+                               text += "\x83";
+                       }
 
-               if (italic) {
-                       text += "\x81";
-               }
+                       if (italic) {
+                               text += "\x81";
+                       }
 
-               if (text.length() > 111) {
-                       text = text.substr (111);
-               }
+                       if (text.length() > 111) {
+                               text = text.substr (111);
+                       }
 
-               while (text.length() < 112) {
-                       text += "\x8F";
-               }
+                       while (text.length() < 112) {
+                               text += "\x8F";
+                       }
 
-               put_string (buffer + 16, text);
-               output.write (buffer, 128);
+                       put_string (buffer + 16, text);
+                       output.write (buffer, 128);
+                       ++line;
+               }
        }
 
        delete[] buffer;