FFmpeg: libavformat/mpsubdec.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 * MPlayer subtitles format demuxer
24 */
25
30
31 #define TSBASE 10000000
32
36
38 {
39 const char *ptr =
p->buf;
40 const char *ptr_end =
p->buf +
p->buf_size;
41
42 while (ptr < ptr_end) {
44
45 if (!memcmp(ptr, "FORMAT=TIME", 11))
47 if (!memcmp(ptr, "FORMAT=", 7))
51 break;
53 }
54 return 0;
55 }
56
58 {
59 int vi, p1, p2;
60
61 for (vi = 0; vi < 2; vi++) {
62 long long intval, fracval;
63 int n =
av_sscanf(
line,
"%lld%n.%lld%n", &intval, &p1, &fracval, &p2);
64 if (n <= 0 || intval < INT64_MIN / TSBASE || intval > INT64_MAX /
TSBASE)
66
68
69 if (n == 2) {
70 if (fracval < 0)
72 for (;p2 - p1 < 7 + 1; p1--)
73 fracval *= 10;
74 for (;p2 - p1 > 7 + 1; p1++)
75 fracval /= 10;
79 } else
81
83
85 }
86
87 return 0;
88 }
89
91 {
94 AVBPrint buf;
96 int res = 0;
99 int common_factor = 0;
100
102
107
109 break;
110
112
113 if (sscanf(
line,
"FORMAT=%d", &fps) == 1 && fps > 3 && fps < 100) {
114 /* frame based timing */
119
121 if (res < 0) goto end;
122 if (buf.len) {
124 if (!sub) {
126 goto end;
127 }
128 if ( current_pts < 0 && start < INT64_MIN - current_pts
129 || current_pts > 0 && start > INT64_MAX - current_pts) {
131 goto end;
132 }
133 sub->
pts = current_pts + start;
134 if (duration < 0 || sub->
pts > INT64_MAX -
duration) {
136 goto end;
137 }
139
141 common_factor =
av_gcd(sub->
pts, common_factor);
142
145 }
146 }
147 }
148
149 if (common_factor > 1) {
150 common_factor =
av_gcd(pts_info.
num, common_factor);
154 }
155 pts_info.
num /= common_factor;
156 }
157
159 if (!st) {
161 goto end;
162 }
166
168
169 end:
171 return res;
172 }
173
177 .p.extensions = "sub",
185 };
int ff_subtitles_read_close(AVFormatContext *s)
#define AV_BPRINT_SIZE_UNLIMITED
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 nb_subs
number of subtitles packets
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
int ff_subtitles_read_chunk(AVIOContext *pb, AVBPrint *buf)
Same as ff_subtitles_read_text_chunk(), but read from an AVIOContext.
int64_t av_gcd(int64_t a, int64_t b)
Compute the greatest common divisor of two integer operands.
static av_cold int read_close(AVFormatContext *ctx)
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
int ff_subtitles_read_packet(AVFormatContext *s, AVPacket *pkt)
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
int av_sscanf(const char *string, const char *format,...)
const FFInputFormat ff_mpsub_demuxer
static int mpsub_read_header(AVFormatContext *s)
#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...
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Rational number (pair of numerator and denominator).
This structure contains the data a format has to probe a file.
static int inc(int num, int period)
#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.
static int mpsub_probe(const AVProbeData *p)
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 int read_header(FFV1Context *f, RangeCoder *c)
AVPacket * ff_subtitles_queue_insert_bprint(FFDemuxSubtitlesQueue *q, const AVBPrint *event, int merge)
Same as ff_subtitles_queue_insert but takes an AVBPrint input.
#define i(width, name, range_min, range_max)
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
AVPacket ** subs
array of subtitles packets
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default value
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.
@ AV_CODEC_ID_TEXT
raw UTF-8 text
IDirect3DDxgiInterfaceAccess _COM_Outptr_ void ** p
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
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
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.
static int parse_line(const char *line, int64_t *value, int64_t *value2)
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
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