FFmpeg: libavformat/jacosubdec.c Source File
Go to the documentation of this file. 1 /*
2 * Copyright (c) 2012 Clément Bœsch
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 /**
22 * @file
23 * JACOsub subtitle demuxer
24 * @see http://unicorn.us.com/jacosub/jscripts.html
25 * @todo Support P[ALETTE] directive.
26 */
27
36
42
44 {
47 return (sscanf(ptr,
"%*u:%*u:%*u.%*u %*u:%*u:%*u.%*u %c", &
c) == 1 ||
48 (sscanf(ptr,
"@%u @%u %c", &
fs, &fe, &
c) == 3 &&
fs < fe));
49 }
50
52 {
53 const char *ptr = p->
buf;
55
57 ptr += 3; /* skip UTF-8 BOM */
58
59 while (ptr < ptr_end) {
61 ptr++;
62 if (*ptr != '#' && *ptr != '\n') {
65 return 0;
66 }
68 }
69 return 0;
70 }
71
72 static const char *
const cmds[] = {
73 "CLOCKPAUSE",
74 "DIRECTIVE",
75 "FONT",
76 "HRES",
77 "INCLUDE",
78 "PALETTE",
79 "QUANTIZE",
80 "RAMP",
81 "SHIFT",
82 "TIMERES",
83 };
84
86 {
88
93 return -1;
94 }
95
98 {
100 unsigned hs, ms,
ss,
fs;
// hours, minutes, seconds, frame start
101 unsigned he,
me,
se, fe;
// hours, minutes, seconds, frame end
102 int ts_start, ts_end;
103 int64_t ts_start64, ts_end64;
104
105 /* timed format */
106 if (sscanf(buf, "%u:%u:%u.%u %u:%u:%u.%u %n",
108 &he, &
me, &
se, &fe, &
len) == 8) {
109 ts_start = (hs*3600 + ms*60 +
ss) * jacosub->
timeres +
fs;
110 ts_end = (he*3600 +
me*60 +
se) * jacosub->
timeres + fe;
111 goto shift_and_ret;
112 }
113
114 /* timestamps format */
115 if (sscanf(buf,
"@%u @%u %n", &ts_start, &ts_end, &
len) == 2)
116 goto shift_and_ret;
117
119
120 shift_and_ret:
121 ts_start64 = (ts_start + (int64_t)jacosub->
shift) * 100LL / jacosub->
timeres;
122 ts_end64 = (ts_end + (int64_t)jacosub->
shift) * 100LL / jacosub->
timeres;
123 *start = ts_start64;
126 }
127
129 {
130 int sign = 1;
131 int a = 0,
b = 0,
c = 0,
d = 0;
133 #define SSEP "%*1[.:]"
135 #undef SSEP
136
138 return 0;
139
140 if (*buf ==
'-' ||
a < 0) {
141 sign = -1;
143 }
144
146 switch (n) {
147 case 4:
148 ret = sign * (((int64_t)
a*3600 +
b*60 +
c) * timeres +
d);
149 break;
150 case 3:
151 ret = sign * (( (int64_t)
a*60 +
b) * timeres +
c);
152 break;
153 case 2:
154 ret = sign * (( (int64_t)
a) * timeres +
b);
155 break;
156 }
159
161 }
162
164 {
169 int shift_set = 0; // only the first shift matters
170 int merge_line = 0;
172
174 if (!st)
179
181
183
185 int cmd_len;
186 const char *p =
line;
189
191
192 /* queue timed line */
195
200 }
202 merge_line =
len > 1 && !strcmp(&
line[
len - 2],
"\\\n");
203 continue;
204 }
205
206 /* skip all non-compiler commands and focus on the command */
207 if (*p != '#')
208 continue;
209 p++;
212 continue;
213
214 /* trim command + spaces */
215 cmd_len = strlen(
cmds[
i]);
217 p += cmd_len;
218 else
219 p++;
221
222 /* handle commands which affect the whole script */
223 switch (
cmds[
i][0]) {
224 case 'S': // SHIFT command affect the whole script...
225 if (!shift_set) {
227 shift_set = 1;
228 }
230 break;
231 case 'T': // ...but must be placed after TIMERES
235 else
237 break;
238 }
239 }
240
241 /* general/essential directives in the extradata */
245
246 /* SHIFT and TIMERES affect the whole script so packet timing can only be
247 * done in a second pass */
251 }
253
254 return 0;
255 }
256
267 };
int ff_subtitles_read_close(AVFormatContext *s)
Filter the word "frame" indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
enum AVMediaType codec_type
General type of the encoded data.
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
static float sub(float src0, float src1)
int nb_subs
number of subtitles packets
#define se(name, range_min, range_max)
int buf_size
Size of buf except extra allocated bytes.
static av_cold int read_close(AVFormatContext *ctx)
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
#define ss(width, name, subs,...)
#define FF_ARRAY_ELEMS(a)
int ff_subtitles_read_packet(AVFormatContext *s, AVPacket *pkt)
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
#define FFABS(a)
Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they are not representable ...
AVCodecParameters * codecpar
Codec parameters associated with this stream.
static int read_header(FFV1Context *f)
#define fs(width, name, subs,...)
This structure contains the data a format has to probe a file.
AVPacket * ff_subtitles_queue_insert(FFDemuxSubtitlesQueue *q, const uint8_t *event, size_t len, int merge)
Insert a new subtitle event.
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
int av_strncasecmp(const char *a, const char *b, size_t n)
Locale-independent case-insensitive compare.
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
static av_always_inline int jss_whitespace(char c)
void ff_subtitles_queue_finalize(void *log_ctx, FFDemuxSubtitlesQueue *q)
Set missing durations, sort subtitles by PTS (and then byte position), and drop duplicated events.
static const uint8_t header[24]
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
static const av_always_inline char * jss_skip_whitespace(const char *p)
#define i(width, name, range_min, range_max)
AVPacket ** subs
array of subtitles packets
static av_const int av_toupper(int c)
Locale-independent conversion of ASCII characters to uppercase.
int ff_subtitles_read_seek(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
int ff_get_line(AVIOContext *s, char *buf, int maxlen)
Read a whole line of text from AVIOContext.
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
void av_bprintf(AVBPrint *buf, const char *fmt,...)
#define AV_INPUT_BUFFER_PADDING_SIZE
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
This structure stores compressed data.
static av_always_inline int ff_subtitles_next_line(const char *ptr)
Get the number of characters to increment to jump to the next line, or to the end of the string.
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_RB24
The official guide to swscale for confused that consecutive non overlapping rectangles of slice_bottom special converter These generally are unscaled converters of common like for each output line the vertical scaler pulls lines from a ring buffer When the ring buffer does not contain the wanted line
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
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