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 substext_updater_region_t substext_updater_region_t;
  29
  30 enum substext_updater_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 substext_updater_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     substext_updater_region_t *p_next;
  55 };
  56
  57 typedef struct
  58 {
  59     /* a min of one region */
  60     substext_updater_region_t region;
  61
  62     /* styling */
  63     text_style_t *p_default_style; /* decoder (full or partial) defaults */
  64     float margin_ratio;
  65     vlc_tick_t i_next_update;
  66     bool b_blink_even;
  67 } subtext_updater_sys_t;
  68
  69 static inline void SubpictureUpdaterSysRegionClean(substext_updater_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(substext_updater_region_t *p_updtregion)
  76 {
  77     memset(p_updtregion, 0, sizeof(*p_updtregion));
  78     p_updtregion->align = SUBPICTURE_ALIGN_BOTTOM;
  79     p_updtregion->inner_align = 0;
  80 }
  81
  82 static inline substext_updater_region_t *SubpictureUpdaterSysRegionNew( )
  83 {
  84     substext_updater_region_t *p_region = malloc(sizeof(*p_region));
  85     if(p_region)
  86         SubpictureUpdaterSysRegionInit(p_region);
  87     return p_region;
  88 }
  89
  90 static inline void SubpictureUpdaterSysRegionAdd(substext_updater_region_t *p_prev,
  91                                                  substext_updater_region_t *p_new)
  92 {
  93     substext_updater_region_t **pp_next = &p_prev->p_next;
  94     for(; *pp_next; pp_next = &(*pp_next)->p_next);
  95     *pp_next = p_new;
  96 }
  97
  98 static int SubpictureTextValidate(subpicture_t *subpic,
  99                                   bool has_src_changed, const video_format_t *fmt_src,
 100                                   bool has_dst_changed, const video_format_t *fmt_dst,
 101                                   vlc_tick_t ts)
 102 {
 103     subtext_updater_sys_t *sys = subpic->updater.p_sys;
 104     VLC_UNUSED(fmt_src); VLC_UNUSED(fmt_dst);
 105
 106     if (!has_src_changed && !has_dst_changed &&
 107         (sys->i_next_update == VLC_TICK_INVALID || sys->i_next_update > ts))
 108         return VLC_SUCCESS;
 109
 110     substext_updater_region_t *p_updtregion = &sys->region;
 111
 112     if (!(p_updtregion->flags & UPDT_REGION_FIXED_DONE) &&
 113         subpic->b_absolute && subpic->p_region &&
 114         subpic->i_original_picture_width > 0 &&
 115         subpic->i_original_picture_height > 0)
 116     {
 117         p_updtregion->flags |= UPDT_REGION_FIXED_DONE;
 118         p_updtregion->origin.x = subpic->p_region->i_x;
 119         p_updtregion->origin.y = subpic->p_region->i_y;
 120         p_updtregion->extent.x = subpic->i_original_picture_width;
 121         p_updtregion->extent.y = subpic->i_original_picture_height;
 122         p_updtregion->flags &= ~(UPDT_REGION_ORIGIN_X_IS_RATIO|UPDT_REGION_ORIGIN_Y_IS_RATIO|
 123                                  UPDT_REGION_EXTENT_X_IS_RATIO|UPDT_REGION_EXTENT_Y_IS_RATIO);
 124     }
 125
 126     return VLC_EGENERIC;
 127 }
 128
 129 static void SubpictureTextUpdate(subpicture_t *subpic,
 130                                  const video_format_t *fmt_src,
 131                                  const video_format_t *fmt_dst,
 132                                  vlc_tick_t ts)
 133 {
 134     subtext_updater_sys_t *sys = subpic->updater.p_sys;
 135     VLC_UNUSED(fmt_src);
 136
 137     if (fmt_dst->i_sar_num <= 0 || fmt_dst->i_sar_den <= 0)
 138         return;
 139
 140     video_format_t fmt;
 141     video_format_Init(&fmt, VLC_CODEC_TEXT);
 142
 143     /* NOTE about fmt_dst:
 144      * fmt_dst area and A/R will change to display once WxH of the
 145      * display is greater than the source video in direct rendering.
 146      * This will cause weird sudded region "moves" or "linebreaks" when
 147      * resizing window, mostly vertically.
 148      * see changes by 4a49754d943560fe79bc42f107d8ce566ea24898 */
 149
 150     if( sys->region.flags & UPDT_REGION_USES_GRID_COORDINATES )
 151     {
 152         fmt.i_sar_num = 4;
 153         fmt.i_sar_den = 3;
 154         subpic->i_original_picture_width  = fmt_dst->i_visible_height * fmt.i_sar_num / fmt.i_sar_den;
 155         subpic->i_original_picture_height = fmt_dst->i_visible_height;
 156     }
 157     else
 158     {
 159         subpic->i_original_picture_width  = fmt_dst->i_width * fmt_dst->i_sar_num / fmt_dst->i_sar_den;
 160         subpic->i_original_picture_height = fmt_dst->i_height;
 161         fmt.i_sar_num = 1;
 162         fmt.i_sar_den = 1;
 163     }
 164
 165     bool b_schedule_blink_update = false;
 166     subpicture_region_t **pp_last_region = &subpic->p_region;
 167
 168     for( substext_updater_region_t *p_updtregion = &sys->region;
 169                                           p_updtregion; p_updtregion = p_updtregion->p_next )
 170     {
 171         subpicture_region_t *r = *pp_last_region = subpicture_region_New(&fmt);
 172         if (!r)
 173             return;
 174         pp_last_region = &r->p_next;
 175
 176         r->p_text = text_segment_Copy( p_updtregion->p_segments );
 177         r->i_align = p_updtregion->align;
 178         r->i_text_align = p_updtregion->inner_align;
 179         r->b_noregionbg = p_updtregion->flags & UPDT_REGION_IGNORE_BACKGROUND;
 180         r->b_gridmode = p_updtregion->flags & UPDT_REGION_USES_GRID_COORDINATES;
 181
 182         if (!(p_updtregion->flags & UPDT_REGION_FIXED_DONE))
 183         {
 184             const float margin_ratio = sys->margin_ratio;
 185             const int   margin_h     = margin_ratio * (( r->b_gridmode ) ? (unsigned) subpic->i_original_picture_width
 186                                                                          : fmt_dst->i_visible_width );
 187             const int   margin_v     = margin_ratio * fmt_dst->i_visible_height;
 188
 189             /* subpic invisible margins sizes */
 190             const int outerright_h = fmt_dst->i_width - (fmt_dst->i_visible_width + fmt_dst->i_x_offset);
 191             const int outerbottom_v = fmt_dst->i_height - (fmt_dst->i_visible_height + fmt_dst->i_y_offset);
 192             /* regions usable */
 193             const int inner_w = fmt_dst->i_visible_width - margin_h * 2;
 194             const int inner_h = fmt_dst->i_visible_height - margin_v * 2;
 195
 196             if (r->i_align & SUBPICTURE_ALIGN_LEFT)
 197                 r->i_x = margin_h + fmt_dst->i_x_offset;
 198             else if (r->i_align & SUBPICTURE_ALIGN_RIGHT)
 199                 r->i_x = margin_h + outerright_h;
 200
 201             if (r->i_align & SUBPICTURE_ALIGN_TOP )
 202                 r->i_y = margin_v + fmt_dst->i_y_offset;
 203             else if (r->i_align & SUBPICTURE_ALIGN_BOTTOM )
 204                 r->i_y = margin_v + outerbottom_v;
 205
 206             if( p_updtregion->flags & UPDT_REGION_ORIGIN_X_IS_RATIO )
 207                 r->i_x += p_updtregion->origin.x * inner_w;
 208             else
 209                 r->i_x += p_updtregion->origin.x;
 210
 211             if( p_updtregion->flags & UPDT_REGION_ORIGIN_Y_IS_RATIO )
 212                 r->i_y += p_updtregion->origin.y * inner_h;
 213             else
 214                 r->i_y += p_updtregion->origin.y;
 215
 216             if( p_updtregion->flags & UPDT_REGION_EXTENT_X_IS_RATIO )
 217                 r->i_max_width += p_updtregion->extent.x * inner_w;
 218             else
 219                 r->i_max_width += p_updtregion->extent.x;
 220
 221             if( p_updtregion->flags & UPDT_REGION_EXTENT_Y_IS_RATIO )
 222                 r->i_max_height += p_updtregion->extent.y * inner_h;
 223             else
 224                 r->i_max_height += p_updtregion->extent.y;
 225
 226         } else {
 227             /* FIXME it doesn't adapt on crop settings changes */
 228             r->i_x = p_updtregion->origin.x * fmt_dst->i_width  / p_updtregion->extent.x;
 229             r->i_y = p_updtregion->origin.y * fmt_dst->i_height / p_updtregion->extent.y;
 230         }
 231
 232         /* Add missing default style, if any, to all segments */
 233         for ( text_segment_t* p_segment = r->p_text; p_segment; p_segment = p_segment->p_next )
 234         {
 235             /* Add decoder defaults */
 236             if( p_segment->style )
 237                 text_style_Merge( p_segment->style, sys->p_default_style, false );
 238             else
 239                 p_segment->style = text_style_Duplicate( sys->p_default_style );
 240
 241             if( p_segment->style )
 242             {
 243                 /* Update all segments font sizes in video source %,
 244                  * so we can handle HiDPI properly and have consistent rendering limits */
 245                  if( p_segment->style->i_font_size > 0 && fmt_src->i_visible_height > 0 )
 246                 {
 247                     p_segment->style->f_font_relsize = 100.0 * p_segment->style->i_font_size / fmt_src->i_visible_height;
 248                     p_segment->style->i_font_size = 0;
 249                 }
 250
 251                 if( p_segment->style->i_style_flags & (STYLE_BLINK_BACKGROUND|STYLE_BLINK_FOREGROUND) )
 252                 {
 253                     if( sys->b_blink_even ) /* do nothing at first */
 254                     {
 255                         if( p_segment->style->i_style_flags & STYLE_BLINK_BACKGROUND )
 256                             p_segment->style->i_background_alpha =
 257                                     (~p_segment->style->i_background_alpha) & 0xFF;
 258                         if( p_segment->style->i_style_flags & STYLE_BLINK_FOREGROUND )
 259                             p_segment->style->i_font_alpha =
 260                                     (~p_segment->style->i_font_alpha) & 0xFF;
 261                     }
 262                     b_schedule_blink_update = true;
 263                 }
 264             }
 265         }
 266     }
 267
 268     if( b_schedule_blink_update &&
 269         (sys->i_next_update == VLC_TICK_INVALID || sys->i_next_update < ts) )
 270     {
 271         sys->i_next_update = ts + VLC_TICK_FROM_SEC(1);
 272         sys->b_blink_even = !sys->b_blink_even;
 273     }
 274 }
 275 static void SubpictureTextDestroy(subpicture_t *subpic)
 276 {
 277     subtext_updater_sys_t *sys = subpic->updater.p_sys;
 278
 279     SubpictureUpdaterSysRegionClean( &sys->region );
 280     substext_updater_region_t *p_region = sys->region.p_next;
 281     while( p_region )
 282     {
 283         substext_updater_region_t *p_next = p_region->p_next;
 284         SubpictureUpdaterSysRegionClean( p_region );
 285         free( p_region );
 286         p_region = p_next;
 287     }
 288     text_style_Delete( sys->p_default_style );
 289     free(sys);
 290 }
 291
 292 static inline subpicture_t *decoder_NewSubpictureText(decoder_t *decoder)
 293 {
 294     subtext_updater_sys_t *sys = calloc(1, sizeof(*sys));
 295     subpicture_updater_t updater = {
 296         .pf_validate = SubpictureTextValidate,
 297         .pf_update   = SubpictureTextUpdate,
 298         .pf_destroy  = SubpictureTextDestroy,
 299         .p_sys       = sys,
 300     };
 301     SubpictureUpdaterSysRegionInit( &sys->region );
 302     sys->margin_ratio = 0.04;
 303     sys->p_default_style = text_style_Create( STYLE_NO_DEFAULTS );
 304     if(unlikely(!sys->p_default_style))
 305     {
 306         free(sys);
 307         return NULL;
 308     }
 309     subpicture_t *subpic = decoder_NewSubpicture(decoder, &updater);
 310     if (!subpic)
 311     {
 312         text_style_Delete(sys->p_default_style);
 313         free(sys);
 314     }
 315     return subpic;
 316 }