libavcodec/ass_split.h

   1 /*
   2  * SSA/ASS spliting functions
   3  * Copyright (c) 2010  Aurelien Jacobs <aurel@gnuage.org>
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #ifndef AVCODEC_ASS_SPLIT_H
  23 #define AVCODEC_ASS_SPLIT_H
  24
  25 /**
  26  * fields extracted from the [Script Info] section
  27  */
  28 typedef struct {
  29     char *script_type;    /**< SSA script format version (eg. v4.00) */
  30     char *collisions;     /**< how subtitles are moved to prevent collisions */
  31     int   play_res_x;     /**< video width that ASS coords are referring to */
  32     int   play_res_y;     /**< video height that ASS coords are referring to */
  33     float timer;          /**< time multiplier to apply to SSA clock (in %) */
  34 } ASSScriptInfo;
  35
  36 /**
  37  * fields extracted from the [V4(+) Styles] section
  38  */
  39 typedef struct {
  40     char *name;           /**< name of the tyle (case sensitive) */
  41     char *font_name;      /**< font face (case sensitive) */
  42     int   font_size;      /**< font height */
  43     int   primary_color;  /**< color that a subtitle will normally appear in */
  44     int   secondary_color;
  45     int   outline_color;  /**< color for outline in ASS, called tertiary in SSA */
  46     int   back_color;     /**< color of the subtitle outline or shadow */
  47     int   bold;           /**< whether text is bold (1) or not (0) */
  48     int   italic;         /**< whether text is italic (1) or not (0) */
  49     int   underline;      /**< whether text is underlined (1) or not (0) */
  50     int   strikeout;
  51     float scalex;
  52     float scaley;
  53     float spacing;
  54     float angle;
  55     int   border_style;
  56     float outline;
  57     float shadow;
  58     int   alignment;      /**< position of the text (left, center, top...),
  59                                defined after the layout of the numpad
  60                                (1-3 sub, 4-6 mid, 7-9 top) */
  61     int   margin_l;
  62     int   margin_r;
  63     int   margin_v;
  64     int   alpha_level;
  65     int   encoding;
  66 } ASSStyle;
  67
  68 /**
  69  * fields extracted from the [Events] section
  70  */
  71 typedef struct {
  72     int   readorder;
  73     int   layer;    /**< higher numbered layers are drawn over lower numbered */
  74     int   start;    /**< start time of the dialog in centiseconds */
  75     int   end;      /**< end time of the dialog in centiseconds */
  76     char *style;    /**< name of the ASSStyle to use with this dialog */
  77     char *name;
  78     int   margin_l;
  79     int   margin_r;
  80     int   margin_v;
  81     char *effect;
  82     char *text;     /**< actual text which will be displayed as a subtitle,
  83                          can include style override control codes (see
  84                          ff_ass_split_override_codes()) */
  85 } ASSDialog;
  86
  87 /**
  88  * structure containing the whole split ASS data
  89  */
  90 typedef struct {
  91     ASSScriptInfo script_info;   /**< general information about the SSA script*/
  92     ASSStyle     *styles;        /**< array of split out styles */
  93     int           styles_count;  /**< number of ASSStyle in the styles array */
  94     ASSDialog    *dialogs;       /**< array of split out dialogs */
  95     int           dialogs_count; /**< number of ASSDialog in the dialogs array*/
  96 } ASS;
  97
  98 /**
  99  * This struct can be casted to ASS to access to the split data.
 100  */
 101 typedef struct ASSSplitContext ASSSplitContext;
 102
 103 /**
 104  * Split a full ASS file or a ASS header from a string buffer and store
 105  * the split structure in a newly allocated context.
 106  *
 107  * @param buf String containing the ASS formatted data.
 108  * @return Newly allocated struct containing split data.
 109  */
 110 ASSSplitContext *ff_ass_split(const char *buf);
 111
 112 /**
 113  * Free a dialogue obtained from ff_ass_split_dialog().
 114  */
 115 void ff_ass_free_dialog(ASSDialog **dialogp);
 116
 117 /**
 118  * Split one ASS Dialogue line from a string buffer.
 119  *
 120  * @param ctx Context previously initialized by ff_ass_split().
 121  * @param buf String containing the ASS "Dialogue" line.
 122  * @return Pointer to the split ASSDialog. Must be freed with ff_ass_free_dialog()
 123  */
 124 ASSDialog *ff_ass_split_dialog(ASSSplitContext *ctx, const char *buf);
 125
 126 /**
 127  * Free all the memory allocated for an ASSSplitContext.
 128  *
 129  * @param ctx Context previously initialized by ff_ass_split().
 130  */
 131 void ff_ass_split_free(ASSSplitContext *ctx);
 132
 133
 134 /**
 135  * Set of callback functions corresponding to each override codes that can
 136  * be encountered in a "Dialogue" Text field.
 137  */
 138 typedef struct {
 139     /**
 140      * @defgroup ass_styles    ASS styles
 141      * @{
 142      */
 143     void (*text)(void *priv, const char *text, int len);
 144     void (*new_line)(void *priv, int forced);
 145     void (*style)(void *priv, char style, int close);
 146     void (*color)(void *priv, unsigned int /* color */, unsigned int color_id);
 147     void (*alpha)(void *priv, int alpha, int alpha_id);
 148     void (*font_name)(void *priv, const char *name);
 149     void (*font_size)(void *priv, int size);
 150     void (*alignment)(void *priv, int alignment);
 151     void (*cancel_overrides)(void *priv, const char *style);
 152     /** @} */
 153
 154     /**
 155      * @defgroup ass_functions    ASS functions
 156      * @{
 157      */
 158     void (*move)(void *priv, int x1, int y1, int x2, int y2, int t1, int t2);
 159     void (*origin)(void *priv, int x, int y);
 160     /** @} */
 161
 162     /**
 163      * @defgroup ass_end    end of Dialogue Event
 164      * @{
 165      */
 166     void (*end)(void *priv);
 167     /** @} */
 168 } ASSCodesCallbacks;
 169
 170 /**
 171  * Split override codes out of a ASS "Dialogue" Text field.
 172  *
 173  * @param callbacks Set of callback functions called for each override code
 174  *                  encountered.
 175  * @param priv Opaque pointer passed to the callback functions.
 176  * @param buf The ASS "Dialogue" Text field to split.
 177  * @return >= 0 on success otherwise an error code <0
 178  */
 179 int ff_ass_split_override_codes(const ASSCodesCallbacks *callbacks, void *priv,
 180                                 const char *buf);
 181
 182 /**
 183  * Find an ASSStyle structure by its name.
 184  *
 185  * @param ctx Context previously initialized by ff_ass_split().
 186  * @param style name of the style to search for.
 187  * @return the ASSStyle corresponding to style, or NULL if style can't be found
 188  */
 189 ASSStyle *ff_ass_style_get(ASSSplitContext *ctx, const char *style);
 190
 191 #endif /* AVCODEC_ASS_SPLIT_H */