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 "config_components.h"
23
24 #include "libavutil/avstring.h"
25 #include "libavutil/common.h"
26 #include "libavutil/intreadwrite.h"
27 #include "libavutil/parseutils.h"
28 #include "avcodec.h"
29 #include "ass.h"
30 #include "codec_internal.h"
31 #include "htmlsubtitles.h"
32
srt_to_ass(AVCodecContext * avctx,AVBPrint * dst,const char * in,int x1,int y1,int x2,int y2)33 static int srt_to_ass(AVCodecContext *avctx, AVBPrint *dst,
34 const char *in, int x1, int y1, int x2, int y2)
35 {
36 if (x1 >= 0 && y1 >= 0) {
37 /* XXX: here we rescale coordinate assuming they are in DVD resolution
38 * (720x480) since we don't have anything better */
39
40 if (x2 >= 0 && y2 >= 0 && (x2 != x1 || y2 != y1) && x2 >= x1 && y2 >= y1) {
41 /* text rectangle defined, write the text at the center of the rectangle */
42 const int cx = x1 + (x2 - x1)/2;
43 const int cy = y1 + (y2 - y1)/2;
44 const int scaled_x = cx * (int64_t)ASS_DEFAULT_PLAYRESX / 720;
45 const int scaled_y = cy * (int64_t)ASS_DEFAULT_PLAYRESY / 480;
46 av_bprintf(dst, "{\\an5}{\\pos(%d,%d)}", scaled_x, scaled_y);
47 } else {
48 /* only the top left corner, assume the text starts in that corner */
49 const int scaled_x = x1 * (int64_t)ASS_DEFAULT_PLAYRESX / 720;
50 const int scaled_y = y1 * (int64_t)ASS_DEFAULT_PLAYRESY / 480;
51 av_bprintf(dst, "{\\an1}{\\pos(%d,%d)}", scaled_x, scaled_y);
52 }
53 }
54
55 return ff_htmlmarkup_to_ass(avctx, dst, in);
56 }
57
srt_decode_frame(AVCodecContext * avctx,AVSubtitle * sub,int * got_sub_ptr,const AVPacket * avpkt)58 static int srt_decode_frame(AVCodecContext *avctx, AVSubtitle *sub,
59 int *got_sub_ptr, const AVPacket *avpkt)
60 {
61 AVBPrint buffer;
62 int x1 = -1, y1 = -1, x2 = -1, y2 = -1;
63 int ret;
64 size_t size;
65 const uint8_t *p = av_packet_get_side_data(avpkt, AV_PKT_DATA_SUBTITLE_POSITION, &size);
66 FFASSDecoderContext *s = avctx->priv_data;
67
68 if (p && size == 16) {
69 x1 = AV_RL32(p );
70 y1 = AV_RL32(p + 4);
71 x2 = AV_RL32(p + 8);
72 y2 = AV_RL32(p + 12);
73 }
74
75 if (avpkt->size <= 0)
76 return avpkt->size;
77
78 av_bprint_init(&buffer, 0, AV_BPRINT_SIZE_UNLIMITED);
79
80 ret = srt_to_ass(avctx, &buffer, avpkt->data, x1, y1, x2, y2);
81 if (ret >= 0)
82 ret = ff_ass_add_rect(sub, buffer.str, s->readorder++, 0, NULL, NULL);
83 av_bprint_finalize(&buffer, NULL);
84 if (ret < 0)
85 return ret;
86
87 *got_sub_ptr = sub->num_rects > 0;
88 return avpkt->size;
89 }
90
91 #if CONFIG_SRT_DECODER
92 /* deprecated decoder */
93 const FFCodec ff_srt_decoder = {
94 .p.name = "srt",
95 .p.long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle"),
96 .p.type = AVMEDIA_TYPE_SUBTITLE,
97 .p.id = AV_CODEC_ID_SUBRIP,
98 .init = ff_ass_subtitle_header_default,
99 FF_CODEC_DECODE_SUB_CB(srt_decode_frame),
100 .flush = ff_ass_decoder_flush,
101 .priv_data_size = sizeof(FFASSDecoderContext),
102 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
103 };
104 #endif
105
106 #if CONFIG_SUBRIP_DECODER
107 const FFCodec ff_subrip_decoder = {
108 .p.name = "subrip",
109 .p.long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle"),
110 .p.type = AVMEDIA_TYPE_SUBTITLE,
111 .p.id = AV_CODEC_ID_SUBRIP,
112 .init = ff_ass_subtitle_header_default,
113 FF_CODEC_DECODE_SUB_CB(srt_decode_frame),
114 .flush = ff_ass_decoder_flush,
115 .priv_data_size = sizeof(FFASSDecoderContext),
116 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
117 };
118 #endif
119