FFmpeg: libavformat/assdec.c Source File
Go to the documentation of this file. 1 /*
2 * SSA/ASS demuxer
3 * Copyright (c) 2008 Michael Niedermayer
4 * Copyright (c) 2014 Clément Bœsch
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23 #include <stdint.h>
24
30
35
37 {
38 char buf[13];
41
44
46
47 if (!memcmp(buf, "[Script Info]", 13))
49
50 return 0;
51 }
52
55 {
58 int hh1, mm1, ss1, ms1;
59 int hh2, mm2, ss2, ms2;
60
61 if (sscanf(p, "Dialogue: %*[^,],%d:%d:%d%*c%d,%d:%d:%d%*c%d,%n",
62 &hh1, &mm1, &ss1, &ms1,
63 &hh2, &mm2, &ss2, &ms2, &
pos) >= 8 &&
pos > 0) {
64
65 /* This is not part of the sscanf itself in order to handle an actual
66 * number (which would be the Layer) or the form "Marked=N" (which is
67 * the old SSA field, now replaced by Layer, and will lead to Layer
68 * being 0 here). */
69 const int layer = atoi(p + 10);
70
71 end = (hh2*3600LL + mm2*60LL + ss2) * 100LL + ms2;
72 *start = (hh1*3600LL + mm1*60LL + ss1) * 100LL + ms1;
74
79
80 /* right strip the buffer */
81 while (
dst->len > 0 &&
82 dst->str[
dst->len - 1] ==
'\r' ||
83 dst->str[
dst->len - 1] ==
'\n')
85 return 0;
86 }
87 return -1;
88 }
89
91 {
93
95 for (;;) {
98 break;
101 break;
102 }
104 }
105
107 {
110 int res = 0;
114
116 if (!st)
121
125
127
128 for (;;) {
133
134 if (!
line.str[0])
// EOF
135 break;
136
139 continue;
140 }
142 if (!sub) {
144 goto end;
145 }
149 }
150
152 if (res < 0)
153 goto end;
154
156
157 end:
161 return res;
162 }
163
174 };
int ff_subtitles_read_close(AVFormatContext *s)
#define AV_BPRINT_SIZE_UNLIMITED
int ff_text_r8(FFTextReader *r)
Return the next byte.
static int av_bprint_is_complete(const AVBPrint *buf)
Test if the print buffer is complete (not truncated).
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
enum AVMediaType codec_type
General type of the encoded data.
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
int keep_duplicates
set to 1 to keep duplicated subtitle events
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
int buf_size
Size of buf except extra allocated bytes.
static av_cold int read_close(AVFormatContext *ctx)
int ff_subtitles_read_packet(AVFormatContext *s, AVPacket *pkt)
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
#define FF_INFMT_FLAG_INIT_CLEANUP
For an FFInputFormat with this flag set read_close() needs to be called by the caller upon read_heade...
void ff_text_read(FFTextReader *r, char *buf, size_t size)
Read the given number of bytes (in UTF-8).
AVCodecParameters * codecpar
Codec parameters associated with this stream.
static int read_header(FFV1Context *f)
This structure contains the data a format has to probe a file.
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
void ff_text_init_avio(void *s, FFTextReader *r, AVIOContext *pb)
Initialize the FFTextReader from the given AVIOContext.
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
uint8_t ptrdiff_t const uint8_t ptrdiff_t int intptr_t intptr_t int int16_t * dst
#define AV_NOPTS_VALUE
Undefined timestamp value.
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]
AVPacket * ff_subtitles_queue_insert_bprint(FFDemuxSubtitlesQueue *q, const AVBPrint *event, int merge)
Same as ff_subtitles_queue_insert but takes an AVBPrint input.
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
int64_t ff_text_pos(FFTextReader *r)
Return the byte position of the next byte returned by ff_text_r8().
int ff_subtitles_read_seek(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
void av_bprintf(AVBPrint *buf, const char *fmt,...)
int ff_text_peek_r8(FFTextReader *r)
Like ff_text_r8(), but don't remove the byte from the buffer.
void av_bprint_clear(AVBPrint *buf)
Reset the string to "" but keep internal allocated data.
void ff_text_init_buf(FFTextReader *r, const void *buf, size_t size)
Similar to ff_text_init_avio(), but sets it up to read from a bounded buffer.
static int read_probe(const AVProbeData *p)
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
This structure stores compressed data.
int64_t pos
byte position in stream, -1 if unknown
void av_bprint_chars(AVBPrint *buf, char c, unsigned n)
Append char c n times to a print buffer.
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
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