FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
ass.c
Go to the documentation of this file.
1 /*
2  * SSA/ASS common 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 #include "avcodec.h"
23 #include "ass.h"
24 #include "libavutil/avassert.h"
25 #include "libavutil/avstring.h"
26 #include "libavutil/bprint.h"
27 #include "libavutil/common.h"
28 
30  const char *font, int font_size,
31  int color, int back_color,
32  int bold, int italic, int underline,
33  int alignment)
34 {
36  "[Script Info]\r\n"
37  "ScriptType: v4.00+\r\n"
38  "\r\n"
39  "[V4+ Styles]\r\n"
40  "Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, AlphaLevel, Encoding\r\n"
41  "Style: Default,%s,%d,&H%x,&H%x,&H%x,&H%x,%d,%d,%d,1,1,0,%d,10,10,10,0,0\r\n"
42  "\r\n"
43  "[Events]\r\n"
44  "Format: Layer, Start, End, Style, Text\r\n",
45  font, font_size, color, color, back_color, back_color,
46  -bold, -italic, -underline, alignment);
47 
48  if (!avctx->subtitle_header)
49  return AVERROR(ENOMEM);
50  avctx->subtitle_header_size = strlen(avctx->subtitle_header);
51  return 0;
52 }
53 
55 {
64 }
65 
66 static void insert_ts(AVBPrint *buf, int ts)
67 {
68  if (ts == -1) {
69  av_bprintf(buf, "9:59:59.99,");
70  } else {
71  int h, m, s;
72 
73  h = ts/360000; ts -= 360000*h;
74  m = ts/ 6000; ts -= 6000*m;
75  s = ts/ 100; ts -= 100*s;
76  av_bprintf(buf, "%d:%02d:%02d.%02d,", h, m, s, ts);
77  }
78 }
79 
80 int ff_ass_bprint_dialog(AVBPrint *buf, const char *dialog,
81  int ts_start, int duration, int raw)
82 {
83  int dlen;
84 
85  if (!raw || raw == 2) {
86  long int layer = 0;
87 
88  if (raw == 2) {
89  /* skip ReadOrder */
90  dialog = strchr(dialog, ',');
91  if (!dialog)
92  return AVERROR_INVALIDDATA;
93  dialog++;
94 
95  /* extract Layer or Marked */
96  layer = strtol(dialog, (char**)&dialog, 10);
97  if (*dialog != ',')
98  return AVERROR_INVALIDDATA;
99  dialog++;
100  }
101  av_bprintf(buf, "Dialogue: %ld,", layer);
102  insert_ts(buf, ts_start);
103  insert_ts(buf, duration == -1 ? -1 : ts_start + duration);
104  if (raw != 2)
105  av_bprintf(buf, "Default,");
106  }
107 
108  dlen = strcspn(dialog, "\n");
109  dlen += dialog[dlen] == '\n';
110 
111  av_bprintf(buf, "%.*s", dlen, dialog);
112  if (raw == 2)
113  av_bprintf(buf, "\r\n");
114 
115  return dlen;
116 }
117 
118 int ff_ass_add_rect(AVSubtitle *sub, const char *dialog,
119  int ts_start, int duration, int raw)
120 {
121  AVBPrint buf;
122  int ret, dlen;
123  AVSubtitleRect **rects;
124 
126  if ((ret = ff_ass_bprint_dialog(&buf, dialog, ts_start, duration, raw)) < 0)
127  goto err;
128  dlen = ret;
129  if (!av_bprint_is_complete(&buf))
130  goto errnomem;
131 
132  rects = av_realloc(sub->rects, (sub->num_rects+1) * sizeof(*sub->rects));
133  if (!rects)
134  goto errnomem;
135  sub->rects = rects;
136  sub->end_display_time = FFMAX(sub->end_display_time, 10 * duration);
137  rects[sub->num_rects] = av_mallocz(sizeof(*rects[0]));
138  rects[sub->num_rects]->type = SUBTITLE_ASS;
139  ret = av_bprint_finalize(&buf, &rects[sub->num_rects]->ass);
140  if (ret < 0)
141  goto err;
142  sub->num_rects++;
143  return dlen;
144 
145 errnomem:
146  ret = AVERROR(ENOMEM);
147 err:
148  av_bprint_finalize(&buf, NULL);
149  return ret;
150 }
151 
152 void ff_ass_bprint_text_event(AVBPrint *buf, const char *p, int size,
153  const char *linebreaks, int keep_ass_markup)
154 {
155  const char *p_end = p + size;
156 
157  for (; p < p_end && *p; p++) {
158 
159  /* forced custom line breaks, not accounted as "normal" EOL */
160  if (linebreaks && strchr(linebreaks, *p)) {
161  av_bprintf(buf, "\\N");
162 
163  /* standard ASS escaping so random characters don't get mis-interpreted
164  * as ASS */
165  } else if (!keep_ass_markup && strchr("{}\\", *p)) {
166  av_bprintf(buf, "\\%c", *p);
167 
168  /* some packets might end abruptly (no \0 at the end, like for example
169  * in some cases of demuxing from a classic video container), some
170  * might be terminated with \n or \r\n which we have to remove (for
171  * consistency with those who haven't), and we also have to deal with
172  * evil cases such as \r at the end of the buffer (and no \0 terminated
173  * character) */
174  } else if (p[0] == '\n') {
175  /* some stuff left so we can insert a line break */
176  if (p < p_end - 1)
177  av_bprintf(buf, "\\N");
178  } else if (p[0] == '\r' && p < p_end - 1 && p[1] == '\n') {
179  /* \r followed by a \n, we can skip it. We don't insert the \N yet
180  * because we don't know if it is followed by more text */
181  continue;
182 
183  /* finally, a sane character */
184  } else {
185  av_bprint_chars(buf, *p, 1);
186  }
187  }
188  av_bprintf(buf, "\r\n");
189 }