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
35
41
43 {
46 return (sscanf(ptr,
"%*u:%*u:%*u.%*u %*u:%*u:%*u.%*u %c", &
c) == 1 ||
47 (sscanf(ptr,
"@%u @%u %c", &
fs, &fe, &
c) == 3 &&
fs < fe));
48 }
49
51 {
52 const char *ptr = p->
buf;
54
56 ptr += 3; /* skip UTF-8 BOM */
57
58 while (ptr < ptr_end) {
60 ptr++;
61 if (*ptr != '#' && *ptr != '\n') {
64 return 0;
65 }
67 }
68 return 0;
69 }
70
71 static const char *
const cmds[] = {
72 "CLOCKPAUSE",
73 "DIRECTIVE",
74 "FONT",
75 "HRES",
76 "INCLUDE",
77 "PALETTE",
78 "QUANTIZE",
79 "RAMP",
80 "SHIFT",
81 "TIMERES",
82 };
83
85 {
87
92 return -1;
93 }
94
97 {
99 unsigned hs, ms,
ss,
fs;
// hours, minutes, seconds, frame start
100 unsigned he,
me,
se, fe;
// hours, minutes, seconds, frame end
101 int ts_start, ts_end;
102 int64_t ts_start64, ts_end64;
103
104 /* timed format */
105 if (sscanf(buf, "%u:%u:%u.%u %u:%u:%u.%u %n",
107 &he, &
me, &
se, &fe, &
len) == 8) {
108 ts_start = (hs*3600 + ms*60 +
ss) * jacosub->
timeres +
fs;
109 ts_end = (he*3600 +
me*60 +
se) * jacosub->
timeres + fe;
110 goto shift_and_ret;
111 }
112
113 /* timestamps format */
114 if (sscanf(buf,
"@%u @%u %n", &ts_start, &ts_end, &
len) == 2)
115 goto shift_and_ret;
116
118
119 shift_and_ret:
120 ts_start64 = (ts_start + (int64_t)jacosub->
shift) * 100LL / jacosub->
timeres;
121 ts_end64 = (ts_end + (int64_t)jacosub->
shift) * 100LL / jacosub->
timeres;
122 *start = ts_start64;
125 }
126
128 {
129 int sign = 1;
130 int a = 0,
b = 0,
c = 0,
d = 0;
132 #define SSEP "%*1[.:]"
134 #undef SSEP
135
137 return 0;
138
139 if (*buf ==
'-' ||
a < 0) {
140 sign = -1;
142 }
143
145 switch (n) {
146 case 4:
147 ret = sign * (((int64_t)
a*3600 +
b*60 +
c) * timeres +
d);
148 break;
149 case 3:
150 ret = sign * (( (int64_t)
a*60 +
b) * timeres +
c);
151 break;
152 case 2:
153 ret = sign * (( (int64_t)
a) * timeres +
b);
154 break;
155 }
158
160 }
161
163 {
168 int shift_set = 0; // only the first shift matters
169 int merge_line = 0;
171
173 if (!st)
178
180
182
184 int cmd_len;
185 const char *p =
line;
188
190
191 /* queue timed line */
194
199 }
201 merge_line =
len > 1 && !strcmp(&
line[
len - 2],
"\\\n");
202 continue;
203 }
204
205 /* skip all non-compiler commands and focus on the command */
206 if (*p != '#')
207 continue;
208 p++;
211 continue;
212
213 /* trim command + spaces */
214 cmd_len = strlen(
cmds[
i]);
216 p += cmd_len;
217 else
218 p++;
220
221 /* handle commands which affect the whole script */
222 switch (
cmds[
i][0]) {
223 case 'S': // SHIFT command affect the whole script...
224 if (!shift_set) {
226 shift_set = 1;
227 }
229 break;
230 case 'T': // ...but must be placed after TIMERES
234 else
236 break;
237 }
238 }
239
240 /* general/essential directives in the extradata */
244
245 /* SHIFT and TIMERES affect the whole script so packet timing can only be
246 * done in a second pass */
250 }
252
253 return 0;
254 }
255
266 };
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.
Generated on Wed Aug 24 2022 21:41:30 for FFmpeg by
doxygen
1.8.17