[vlc-devel] Re: [PATCH] italic tag support fo MPL2 subtitles

[Roman Bednarek]

On Wed, 21 Feb 2007, Remi Denis-Courmont wrote:

>>    I just postponed adding a de-escaping function, where should I place
>> it?
>
> Depends how complicated it is. Trivial functions can be inlined in include/
> More complex ones can go in src/text/ if code duplication is to be avoided.
>

  Second version of the MPL2 italic patch.
   I have changed the escape code to ESC=27, and added StripControlCodes 
function to not supported renderers (win32text and svg). I have copied the 
function twice, I do know know how to add new file properly.
   I do not see more problems with it, if you generally accept the idea of 
embedding control codes into text.
   I thought about proposed ANSI escape codes and pango markup language, 
but I wanted something very simple and rich enough for subtitle needs.


Regards
Roman Bednarek
-------------- next part --------------
Index: modules/demux/subtitle.c
===================================================================
--- modules/demux/subtitle.c    (revision 18935)
+++ modules/demux/subtitle.c    (working copy)
@@ -1311,8 +1311,12 @@
     char buffer_text[MAX_LINE + 1];
     int    i_start;
     int    i_stop;
-    unsigned int i;
+    unsigned int i,j;
 
+    char output_text[MAX_LINE + 1];
+    int output_italic;
+    int output_start_line;
+
     p_subtitle->i_start = 0;
     p_subtitle->i_stop  = 0;
     p_subtitle->psz_text = NULL;
@@ -1334,16 +1338,45 @@
         }
     }
 
-    /* replace | by \n */
-    for( i = 0; i < strlen( buffer_text ); i++ )
+    memset( output_text, '\0', MAX_LINE );
+    output_start_line = VLC_TRUE;
+    output_italic = VLC_FALSE;
+    for( i = 0,j=0; i < strlen( buffer_text ) && j<MAX_LINE-2; i++ )
     {
+        if( output_start_line )
+        {
+           output_start_line = VLC_FALSE;
+           if( buffer_text[i] == '/' )
+           {
+               if( !output_italic )
+               {
+                   output_text[j++] = 27;
+                   output_text[j++] = 'I';
+                   output_italic = VLC_TRUE;
+               }
+               continue;
+           }
+           else if( buffer_text[i] != '/' && output_italic )
+           {
+                output_text[j++] = 27;
+                output_text[j++] = 'i';
+                output_italic = VLC_FALSE;
+           }
+        }
         if( buffer_text[i] == '|' )
         {
-            buffer_text[i] = '\n';
+            output_text[j++] = '\n';
+            output_start_line=VLC_TRUE;
         }
+        else
+        {
+            output_text[j++] = buffer_text[i];
+        }
     }
+    output_text[j]=0;
+
     p_subtitle->i_start = (int64_t)i_start * 100000;
     p_subtitle->i_stop  = (int64_t)i_stop  * 100000;
-    p_subtitle->psz_text = strndup( buffer_text, MAX_LINE );
+    p_subtitle->psz_text = strndup( output_text, MAX_LINE );
     return( 0 );
 }
Index: modules/misc/svg.c
===================================================================
--- modules/misc/svg.c  (revision 18935)
+++ modules/misc/svg.c  (working copy)
@@ -58,7 +58,29 @@
 static int  RenderText( filter_t *p_filter, subpicture_region_t *p_region_out,
                         subpicture_region_t *p_region_in );
 
+static void StripControlCodes( char *psz_text )
+{
+    int i_left_moves = 0;
+    int i = 0;
+   
+    if( !psz_text ) return;
 
+    while( psz_text[ i ] )
+    {
+        if( psz_text[ i ] == 27 )
+        {
+            i++;
+            i_left_moves+=2;
+        }
+        else
+        {
+            psz_text[ i - i_left_moves ] = psz_text[ i ];
+        }
+        i++;
+    }
+    psz_text[ i - i_left_moves ] = '\0';
+}
+
 /*****************************************************************************
  * Module descriptor
  *****************************************************************************/
@@ -445,6 +467,8 @@
     psz_string = p_region_in->psz_text;
     if( !psz_string || !*psz_string ) return VLC_EGENERIC;
 
+    StripControlCodes(psz_string);
+
     p_svg = ( svg_rendition_t * )malloc( sizeof( svg_rendition_t ) );
     if( !p_svg )
     {
Index: modules/misc/win32text.c
===================================================================
--- modules/misc/win32text.c    (revision 18935)
+++ modules/misc/win32text.c    (working copy)
@@ -48,6 +48,29 @@
 static int Render( filter_t *, subpicture_region_t *, uint8_t *, int, int);
 static int SetFont( filter_t *, int );
 
+static void StripControlCodes( char *psz_text )
+{
+    int i_left_moves = 0;
+    int i = 0;
+   
+    if( !psz_text ) return;
+
+    while( psz_text[ i ] )
+    {
+        if( psz_text[ i ] == 27 )
+        {
+            i++;
+            i_left_moves+=2;
+        }
+        else
+        {
+            psz_text[ i - i_left_moves ] = psz_text[ i ];
+        }
+        i++;
+    }
+    psz_text[ i - i_left_moves ] = '\0';
+}
+
 /*****************************************************************************
  * Module descriptor
  *****************************************************************************/
@@ -307,6 +330,9 @@
 
     /* Sanity check */
     if( !p_region_in || !p_region_out ) return VLC_EGENERIC;
+
+    StripControlCodes( p_region_in->psz_text );
+
 #ifdef UNICODE
     psz_string = malloc( (strlen( p_region_in->psz_text )+1) * sizeof(TCHAR) );
     if( mbstowcs( psz_string, p_region_in->psz_text,
Index: modules/misc/freetype.c
===================================================================
--- modules/misc/freetype.c     (revision 18935)
+++ modules/misc/freetype.c     (working copy)
@@ -829,6 +829,9 @@
 #define face p_sys->p_face
 #define glyph face->glyph
 
+    // reset transform
+    FT_Set_Transform( face, NULL, NULL );
+
     while( *psz_unicode )
     {
         i_char = *psz_unicode++;
@@ -837,6 +840,28 @@
             continue;
         }
 
+        if( i_char == 27 ) // control code
+        {
+            i_char = *psz_unicode++;
+            if( !i_char ) break;
+
+            if( i_char == 'I' )
+            {
+                FT_Matrix slantMat;
+                slantMat.xx = (1 << 16);
+                slantMat.xy = ((1 << 16) >> 2);
+                slantMat.yx = 0;
+                slantMat.yy = (1 << 16);
+                FT_Set_Transform( face, &slantMat, NULL );
+                continue;
+            }
+            else if( i_char == 'i' )
+            {
+                FT_Set_Transform( face, NULL, NULL );
+                continue;
+            }
+        }
+
         if( i_char == '\n' )
         {
             psz_line_start = psz_unicode;