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srtdec.c
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1 /*
2  * SubRip subtitle decoder
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 "libavutil/avstring.h"
23 #include "libavutil/common.h"
24 #include "libavutil/intreadwrite.h"
25 #include "libavutil/parseutils.h"
26 #include "avcodec.h"
27 #include "ass.h"
28 #include "htmlsubtitles.h"
29 
30 static void srt_to_ass(AVCodecContext *avctx, AVBPrint *dst,
31  const char *in, int x1, int y1, int x2, int y2)
32 {
33  if (x1 >= 0 && y1 >= 0) {
34  /* XXX: here we rescale coordinate assuming they are in DVD resolution
35  * (720x480) since we don't have anything better */
36 
37  if (x2 >= 0 && y2 >= 0 && (x2 != x1 || y2 != y1) && x2 >= x1 && y2 >= y1) {
38  /* text rectangle defined, write the text at the center of the rectangle */
39  const int cx = x1 + (x2 - x1)/2;
40  const int cy = y1 + (y2 - y1)/2;
41  const int scaled_x = cx * ASS_DEFAULT_PLAYRESX / 720;
42  const int scaled_y = cy * ASS_DEFAULT_PLAYRESY / 480;
43  av_bprintf(dst, "{\\an5}{\\pos(%d,%d)}", scaled_x, scaled_y);
44  } else {
45  /* only the top left corner, assume the text starts in that corner */
46  const int scaled_x = x1 * ASS_DEFAULT_PLAYRESX / 720;
47  const int scaled_y = y1 * ASS_DEFAULT_PLAYRESY / 480;
48  av_bprintf(dst, "{\\an1}{\\pos(%d,%d)}", scaled_x, scaled_y);
49  }
50  }
51 
52  ff_htmlmarkup_to_ass(avctx, dst, in);
53 }
54 
55 static int srt_decode_frame(AVCodecContext *avctx,
56  void *data, int *got_sub_ptr, AVPacket *avpkt)
57 {
58  AVSubtitle *sub = data;
59  AVBPrint buffer;
60  int x1 = -1, y1 = -1, x2 = -1, y2 = -1;
61  int size, ret;
64 
65  if (p && size == 16) {
66  x1 = AV_RL32(p );
67  y1 = AV_RL32(p + 4);
68  x2 = AV_RL32(p + 8);
69  y2 = AV_RL32(p + 12);
70  }
71 
72  if (avpkt->size <= 0)
73  return avpkt->size;
74 
76 
77  srt_to_ass(avctx, &buffer, avpkt->data, x1, y1, x2, y2);
78  ret = ff_ass_add_rect(sub, buffer.str, s->readorder++, 0, NULL, NULL);
79  av_bprint_finalize(&buffer, NULL);
80  if (ret < 0)
81  return ret;
82 
83  *got_sub_ptr = sub->num_rects > 0;
84  return avpkt->size;
85 }
86 
87 #if CONFIG_SRT_DECODER
88 /* deprecated decoder */
89 AVCodec ff_srt_decoder = {
90  .name = "srt",
91  .long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle"),
92  .type = AVMEDIA_TYPE_SUBTITLE,
93  .id = AV_CODEC_ID_SUBRIP,
95  .decode = srt_decode_frame,
96  .flush = ff_ass_decoder_flush,
97  .priv_data_size = sizeof(FFASSDecoderContext),
98 };
99 #endif
100 
101 #if CONFIG_SUBRIP_DECODER
102 AVCodec ff_subrip_decoder = {
103  .name = "subrip",
104  .long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle"),
105  .type = AVMEDIA_TYPE_SUBTITLE,
106  .id = AV_CODEC_ID_SUBRIP,
108  .decode = srt_decode_frame,
109  .flush = ff_ass_decoder_flush,
110  .priv_data_size = sizeof(FFASSDecoderContext),
111 };
112 #endif
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:631
void av_bprintf(AVBPrint *buf, const char *fmt,...)
Definition: bprint.c:94
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
Subtitle event position.
Definition: avcodec.h:1476
int size
Definition: avcodec.h:1578
unsigned num_rects
Definition: avcodec.h:3895
int ff_ass_add_rect(AVSubtitle *sub, const char *dialog, int readorder, int layer, const char *style, const char *speaker)
Add an ASS dialog to a subtitle.
Definition: ass.c:101
AVCodec.
Definition: avcodec.h:3535
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
Definition: bprint.c:235
static void srt_to_ass(AVCodecContext *avctx, AVBPrint *dst, const char *in, int x1, int y1, int x2, int y2)
Definition: srtdec.c:30
uint8_t
int ff_ass_subtitle_header_default(AVCodecContext *avctx)
Generate a suitable AVCodecContext.subtitle_header for SUBTITLE_ASS with default style.
Definition: ass.c:80
uint8_t * data
Definition: avcodec.h:1577
ptrdiff_t size
Definition: opengl_enc.c:101
#define ASS_DEFAULT_PLAYRESY
Definition: ass.h:29
#define AV_BPRINT_SIZE_UNLIMITED
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
Definition: bprint.c:69
const char * name
Name of the codec implementation.
Definition: avcodec.h:3542
Libavcodec external API header.
void ff_htmlmarkup_to_ass(void *log_ctx, AVBPrint *dst, const char *in)
Definition: htmlsubtitles.c:53
main external API structure.
Definition: avcodec.h:1642
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31))))#defineSET_CONV_FUNC_GROUP(ofmt, ifmt) staticvoidset_generic_function(AudioConvert *ac){}voidff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, intsample_rate, intapply_map){AudioConvert *ac;intin_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) returnNULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt)>2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);returnNULL;}returnac;}in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}elseif(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;elseac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);returnac;}intff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){intuse_generic=1;intlen=in->nb_samples;intp;if(ac->dc){av_log(ac->avr, AV_LOG_TRACE,"%dsamples-audio_convert:%sto%s(dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));returnff_convert_dither(ac-> in
void ff_ass_decoder_flush(AVCodecContext *avctx)
Helper to flush a text subtitles decoder making use of the FFASSDecoderContext.
Definition: ass.c:124
misc parsing utilities
common internal and external API header
void * priv_data
Definition: avcodec.h:1684
uint8_t * av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:320
static int srt_decode_frame(AVCodecContext *avctx, void *data, int *got_sub_ptr, AVPacket *avpkt)
Definition: srtdec.c:55
#define ASS_DEFAULT_PLAYRESX
Definition: ass.h:28
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1554
GLuint buffer
Definition: opengl_enc.c:102