xref: /third_party/ffmpeg/libavcodec/ass_split.h (revision cabdff1a) 
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 */
28typedef 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 */
39typedef 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 */
71typedef 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 */
90typedef 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 */
101typedef 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 */
110ASSSplitContext *ff_ass_split(const char *buf);
111
112/**
113 * Free a dialogue obtained from ff_ass_split_dialog().
114 */
115void 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 */
124ASSDialog *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 */
131void 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 */
138typedef 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 */
179int 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 */
189ASSStyle *ff_ass_style_get(ASSSplitContext *ctx, const char *style);
190
191#endif /* AVCODEC_ASS_SPLIT_H */
192