modules/codec/substext.h

   1 /*****************************************************************************
   2  * subsdec.c : text subtitle decoder
   3  *****************************************************************************
   4  * Copyright © 2011-2015 VLC authors and VideoLAN
   5  *
   6  * Authors: Laurent Aimer <fenrir@videolan.org>
   7  *          Jean-Baptiste Kempf <jb@videolan.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU Lesser General Public License as published by
  11  * the Free Software Foundation; either version 2.1 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17  * GNU Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public License
  20  * along with this program; if not, write to the Free Software Foundation,
  21  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 #include <vlc_strings.h>
  25 #include <vlc_text_style.h>
  26 #include <vlc_subpicture.h>
  27
  28 typedef struct subpicture_updater_sys_region_t subpicture_updater_sys_region_t;
  29
  30 enum subpicture_updater_sys_region_flags_e
  31 {
  32     UPDT_REGION_ORIGIN_X_IS_RATIO      = 1 << 0,
  33     UPDT_REGION_ORIGIN_Y_IS_RATIO      = 1 << 1,
  34     UPDT_REGION_EXTENT_X_IS_RATIO      = 1 << 2,
  35     UPDT_REGION_EXTENT_Y_IS_RATIO      = 1 << 3,
  36     UPDT_REGION_IGNORE_BACKGROUND      = 1 << 4,
  37     UPDT_REGION_USES_GRID_COORDINATES  = 1 << 5,
  38     UPDT_REGION_FIXED_DONE             = 1 << 31,
  39 };
  40
  41 struct subpicture_updater_sys_region_t
  42 {
  43     struct
  44     {
  45         float x;
  46         float y;
  47     } origin, extent;
  48     /* store above percentile meanings as modifier flags */
  49     int flags; /* subpicture_updater_sys_region_flags_e */
  50     int align; /* alignment of the region itself */
  51     int inner_align; /* alignment of content inside the region */
  52     text_style_t *p_region_style;
  53     text_segment_t *p_segments;
  54     subpicture_updater_sys_region_t *p_next;
  55 };
  56
  57 struct subpicture_updater_sys_t {
  58
  59     /* a min of one region */
  60     subpicture_updater_sys_region_t region;
  61
  62     /* styling */
  63     text_style_t *p_default_style; /* decoder (full or partial) defaults */
  64     float margin_ratio;
  65     mtime_t i_next_update;
  66     bool b_blink_even;
  67 };
  68
  69 static inline void SubpictureUpdaterSysRegionClean(subpicture_updater_sys_region_t *p_updtregion)
  70 {
  71     text_segment_ChainDelete( p_updtregion->p_segments );
  72     text_style_Delete( p_updtregion->p_region_style );
  73 }
  74
  75 static inline void SubpictureUpdaterSysRegionInit(subpicture_updater_sys_region_t *p_updtregion)
  76 {
  77     memset(p_updtregion, 0, sizeof(*p_updtregion));
  78 }
  79
  80 static inline subpicture_updater_sys_region_t *SubpictureUpdaterSysRegionNew( )
  81 {
  82     subpicture_updater_sys_region_t *p_region = malloc(sizeof(*p_region));
  83     if(p_region)
  84         SubpictureUpdaterSysRegionInit(p_region);
  85     return p_region;
  86 }
  87
  88 static inline void SubpictureUpdaterSysRegionAdd(subpicture_updater_sys_region_t *p_prev,
  89                                                  subpicture_updater_sys_region_t *p_new)
  90 {
  91     subpicture_updater_sys_region_t **pp_next = &p_prev->p_next;
  92     for(; *pp_next; pp_next = &(*pp_next)->p_next);
  93     *pp_next = p_new;
  94 }
  95
  96 static int SubpictureTextValidate(subpicture_t *subpic,
  97                                   bool has_src_changed, const video_format_t *fmt_src,
  98                                   bool has_dst_changed, const video_format_t *fmt_dst,
  99                                   mtime_t ts)
 100 {
 101     subpicture_updater_sys_t *sys = subpic->updater.p_sys;
 102     VLC_UNUSED(fmt_src); VLC_UNUSED(fmt_dst);
 103
 104     if (!has_src_changed && !has_dst_changed &&
 105         (sys->i_next_update == VLC_TS_INVALID || sys->i_next_update > ts))
 106         return VLC_SUCCESS;
 107
 108     subpicture_updater_sys_region_t *p_updtregion = &sys->region;
 109
 110     if (!(p_updtregion->flags & UPDT_REGION_FIXED_DONE) &&
 111         subpic->b_absolute && subpic->p_region &&
 112         subpic->i_original_picture_width > 0 &&
 113         subpic->i_original_picture_height > 0)
 114     {
 115         p_updtregion->flags |= UPDT_REGION_FIXED_DONE;
 116         p_updtregion->origin.x = subpic->p_region->i_x;
 117         p_updtregion->origin.y = subpic->p_region->i_y;
 118         p_updtregion->extent.x = subpic->i_original_picture_width;
 119         p_updtregion->extent.y = subpic->i_original_picture_height;
 120         p_updtregion->flags &= ~(UPDT_REGION_ORIGIN_X_IS_RATIO|UPDT_REGION_ORIGIN_Y_IS_RATIO|
 121                                  UPDT_REGION_EXTENT_X_IS_RATIO|UPDT_REGION_EXTENT_Y_IS_RATIO);
 122     }
 123
 124     return VLC_EGENERIC;
 125 }
 126
 127 static void SubpictureTextUpdate(subpicture_t *subpic,
 128                                  const video_format_t *fmt_src,
 129                                  const video_format_t *fmt_dst,
 130                                  mtime_t ts)
 131 {
 132     subpicture_updater_sys_t *sys = subpic->updater.p_sys;
 133     VLC_UNUSED(fmt_src);
 134
 135     if (fmt_dst->i_sar_num <= 0 || fmt_dst->i_sar_den <= 0)
 136         return;
 137
 138     video_format_t fmt;
 139     video_format_Init(&fmt, VLC_CODEC_TEXT);
 140
 141     if( sys->region.flags & UPDT_REGION_USES_GRID_COORDINATES )
 142     {
 143         fmt.i_sar_num = 4;
 144         fmt.i_sar_den = 3;
 145         subpic->i_original_picture_width  = fmt_dst->i_visible_height * fmt.i_sar_num / fmt.i_sar_den;
 146         subpic->i_original_picture_height = fmt_dst->i_visible_height;
 147     }
 148     else
 149     {
 150         subpic->i_original_picture_width  = fmt_dst->i_width * fmt_dst->i_sar_num / fmt_dst->i_sar_den;
 151         subpic->i_original_picture_height = fmt_dst->i_height;
 152         fmt.i_sar_num = 1;
 153         fmt.i_sar_den = 1;
 154     }
 155
 156     bool b_schedule_blink_update = false;
 157     subpicture_region_t **pp_last_region = &subpic->p_region;
 158
 159     for( subpicture_updater_sys_region_t *p_updtregion = &sys->region;
 160                                           p_updtregion; p_updtregion = p_updtregion->p_next )
 161     {
 162         subpicture_region_t *r = *pp_last_region = subpicture_region_New(&fmt);
 163         if (!r)
 164             return;
 165         pp_last_region = &r->p_next;
 166
 167         r->p_text = text_segment_Copy( p_updtregion->p_segments );
 168         r->i_align  = p_updtregion->inner_align | p_updtregion->align; /* we do not support text align by itself */
 169         r->b_noregionbg = p_updtregion->flags & UPDT_REGION_IGNORE_BACKGROUND;
 170         r->b_gridmode = p_updtregion->flags & UPDT_REGION_USES_GRID_COORDINATES;
 171
 172         if (!(p_updtregion->flags & UPDT_REGION_FIXED_DONE))
 173         {
 174             const float margin_ratio = sys->margin_ratio;
 175             const int   margin_h     = margin_ratio * (( r->b_gridmode ) ? (unsigned) subpic->i_original_picture_width
 176                                                                          : fmt_dst->i_visible_width );
 177             const int   margin_v     = margin_ratio * fmt_dst->i_visible_height;
 178
 179             /* subpic invisible margins sizes */
 180             const int outerright_h = fmt_dst->i_width - (fmt_dst->i_visible_width + fmt_dst->i_x_offset);
 181             const int outerbottom_v = fmt_dst->i_height - (fmt_dst->i_visible_height + fmt_dst->i_y_offset);
 182             /* regions usable */
 183             const int inner_w = fmt_dst->i_visible_width - margin_h * 2;
 184             const int inner_h = fmt_dst->i_visible_height - margin_v * 2;
 185
 186             if (r->i_align & SUBPICTURE_ALIGN_LEFT)
 187                 r->i_x = margin_h + fmt_dst->i_x_offset;
 188             else if (r->i_align & SUBPICTURE_ALIGN_RIGHT)
 189                 r->i_x = margin_h + outerright_h;
 190
 191             if (r->i_align & SUBPICTURE_ALIGN_TOP )
 192                 r->i_y = margin_v + fmt_dst->i_y_offset;
 193             else if (r->i_align & SUBPICTURE_ALIGN_BOTTOM )
 194                 r->i_y = margin_v + outerbottom_v;
 195
 196             if( p_updtregion->flags & UPDT_REGION_ORIGIN_X_IS_RATIO )
 197                 r->i_x += p_updtregion->origin.x * inner_w;
 198             else
 199                 r->i_x += p_updtregion->origin.x;
 200
 201             if( p_updtregion->flags & UPDT_REGION_ORIGIN_Y_IS_RATIO )
 202                 r->i_y += p_updtregion->origin.y * inner_h;
 203             else
 204                 r->i_y += p_updtregion->origin.y;
 205
 206         } else {
 207             /* FIXME it doesn't adapt on crop settings changes */
 208             r->i_x = p_updtregion->origin.x * fmt_dst->i_width  / p_updtregion->extent.x;
 209             r->i_y = p_updtregion->origin.y * fmt_dst->i_height / p_updtregion->extent.y;
 210         }
 211
 212         /* Add missing default style, if any, to all segments */
 213         for ( text_segment_t* p_segment = r->p_text; p_segment; p_segment = p_segment->p_next )
 214         {
 215             /* Add decoder defaults */
 216             if( p_segment->style )
 217                 text_style_Merge( p_segment->style, sys->p_default_style, false );
 218             else
 219                 p_segment->style = text_style_Duplicate( sys->p_default_style );
 220
 221             if( p_segment->style )
 222             {
 223                 /* Update all segments font sizes in pixels, *** metric used by renderers *** */
 224                 /* We only do this when a fixed font size isn't set */
 225                 if( p_segment->style && p_segment->style->f_font_relsize && !p_segment->style->i_font_size )
 226                 {
 227                     p_segment->style->i_font_size = p_segment->style->f_font_relsize *
 228                                                     subpic->i_original_picture_height / 100;
 229                 }
 230
 231                 if( p_segment->style->i_style_flags & (STYLE_BLINK_BACKGROUND|STYLE_BLINK_FOREGROUND) )
 232                 {
 233                     if( sys->b_blink_even ) /* do nothing at first */
 234                     {
 235                         if( p_segment->style->i_style_flags & STYLE_BLINK_BACKGROUND )
 236                             p_segment->style->i_background_alpha =
 237                                     (~p_segment->style->i_background_alpha) & 0xFF;
 238                         if( p_segment->style->i_style_flags & STYLE_BLINK_FOREGROUND )
 239                             p_segment->style->i_font_alpha =
 240                                     (~p_segment->style->i_font_alpha) & 0xFF;
 241                     }
 242                     b_schedule_blink_update = true;
 243                 }
 244             }
 245         }
 246     }
 247
 248     if( b_schedule_blink_update &&
 249         (sys->i_next_update == VLC_TS_INVALID || sys->i_next_update < ts) )
 250     {
 251         sys->i_next_update = ts + CLOCK_FREQ;
 252         sys->b_blink_even = !sys->b_blink_even;
 253     }
 254 }
 255 static void SubpictureTextDestroy(subpicture_t *subpic)
 256 {
 257     subpicture_updater_sys_t *sys = subpic->updater.p_sys;
 258
 259     SubpictureUpdaterSysRegionClean( &sys->region );
 260     subpicture_updater_sys_region_t *p_region = sys->region.p_next;
 261     while( p_region )
 262     {
 263         subpicture_updater_sys_region_t *p_next = p_region->p_next;
 264         SubpictureUpdaterSysRegionClean( p_region );
 265         free( p_region );
 266         p_region = p_next;
 267     }
 268     text_style_Delete( sys->p_default_style );
 269     free(sys);
 270 }
 271
 272 static inline subpicture_t *decoder_NewSubpictureText(decoder_t *decoder)
 273 {
 274     subpicture_updater_sys_t *sys = calloc(1, sizeof(*sys));
 275     subpicture_updater_t updater = {
 276         .pf_validate = SubpictureTextValidate,
 277         .pf_update   = SubpictureTextUpdate,
 278         .pf_destroy  = SubpictureTextDestroy,
 279         .p_sys       = sys,
 280     };
 281     SubpictureUpdaterSysRegionInit( &sys->region );
 282     sys->margin_ratio = 0.04;
 283     sys->p_default_style = text_style_Create( STYLE_NO_DEFAULTS );
 284     if(unlikely(!sys->p_default_style))
 285     {
 286         free(sys);
 287         return NULL;
 288     }
 289     subpicture_t *subpic = decoder_NewSubpicture(decoder, &updater);
 290     if (!subpic)
 291     {
 292         text_style_Delete(sys->p_default_style);
 293         free(sys);
 294     }
 295     return subpic;
 296 }