xref: /third_party/ffmpeg/libavcodec/textdec.c (revision cabdff1a)
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 * Raw subtitles decoder
24 */
25
26#include "config_components.h"
27
28#include "avcodec.h"
29#include "ass.h"
30#include "codec_internal.h"
31#include "libavutil/bprint.h"
32#include "libavutil/opt.h"
33
34typedef struct {
35    AVClass *class;
36    const char *linebreaks;
37    int keep_ass_markup;
38    int readorder;
39} TextContext;
40
41#define OFFSET(x) offsetof(TextContext, x)
42#define SD AV_OPT_FLAG_SUBTITLE_PARAM | AV_OPT_FLAG_DECODING_PARAM
43static const AVOption options[] = {
44    { "keep_ass_markup", "Set if ASS tags must be escaped", OFFSET(keep_ass_markup), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, .flags=SD },
45    { NULL }
46};
47
48static int text_decode_frame(AVCodecContext *avctx, AVSubtitle *sub,
49                             int *got_sub_ptr, const AVPacket *avpkt)
50{
51    int ret = 0;
52    AVBPrint buf;
53    const char *ptr = avpkt->data;
54    TextContext *text = avctx->priv_data;
55
56    av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED);
57    if (ptr && avpkt->size > 0 && *ptr) {
58        ff_ass_bprint_text_event(&buf, ptr, avpkt->size, text->linebreaks, text->keep_ass_markup);
59        ret = ff_ass_add_rect(sub, buf.str, text->readorder++, 0, NULL, NULL);
60    }
61    av_bprint_finalize(&buf, NULL);
62    if (ret < 0)
63        return ret;
64    *got_sub_ptr = sub->num_rects > 0;
65    return avpkt->size;
66}
67
68static void text_flush(AVCodecContext *avctx)
69{
70    TextContext *text = avctx->priv_data;
71    if (!(avctx->flags2 & AV_CODEC_FLAG2_RO_FLUSH_NOOP))
72        text->readorder = 0;
73}
74
75static const AVClass textsub_decoder_class = {
76    .class_name = "text/vplayer/stl/pjs/subviewer1 decoder",
77    .item_name  = av_default_item_name,
78    .option     = options,
79    .version    = LIBAVUTIL_VERSION_INT,
80};
81
82#if CONFIG_TEXT_DECODER
83const FFCodec ff_text_decoder = {
84    .p.name         = "text",
85    .p.long_name    = NULL_IF_CONFIG_SMALL("Raw text subtitle"),
86    .priv_data_size = sizeof(TextContext),
87    .p.type         = AVMEDIA_TYPE_SUBTITLE,
88    .p.id           = AV_CODEC_ID_TEXT,
89    FF_CODEC_DECODE_SUB_CB(text_decode_frame),
90    .init           = ff_ass_subtitle_header_default,
91    .p.priv_class   = &textsub_decoder_class,
92    .flush          = text_flush,
93    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
94};
95#endif
96
97#if CONFIG_VPLAYER_DECODER || CONFIG_PJS_DECODER || CONFIG_SUBVIEWER1_DECODER || CONFIG_STL_DECODER
98
99static int linebreak_init(AVCodecContext *avctx)
100{
101    TextContext *text = avctx->priv_data;
102    text->linebreaks = "|";
103    return ff_ass_subtitle_header_default(avctx);
104}
105
106#if CONFIG_VPLAYER_DECODER
107const FFCodec ff_vplayer_decoder = {
108    .p.name         = "vplayer",
109    .p.long_name    = NULL_IF_CONFIG_SMALL("VPlayer subtitle"),
110    .priv_data_size = sizeof(TextContext),
111    .p.type         = AVMEDIA_TYPE_SUBTITLE,
112    .p.id           = AV_CODEC_ID_VPLAYER,
113    FF_CODEC_DECODE_SUB_CB(text_decode_frame),
114    .init           = linebreak_init,
115    .p.priv_class   = &textsub_decoder_class,
116    .flush          = text_flush,
117    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
118};
119#endif
120
121#if CONFIG_STL_DECODER
122const FFCodec ff_stl_decoder = {
123    .p.name         = "stl",
124    .p.long_name    = NULL_IF_CONFIG_SMALL("Spruce subtitle format"),
125    .priv_data_size = sizeof(TextContext),
126    .p.type         = AVMEDIA_TYPE_SUBTITLE,
127    .p.id           = AV_CODEC_ID_STL,
128    FF_CODEC_DECODE_SUB_CB(text_decode_frame),
129    .init           = linebreak_init,
130    .p.priv_class   = &textsub_decoder_class,
131    .flush          = text_flush,
132    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
133};
134#endif
135
136#if CONFIG_PJS_DECODER
137const FFCodec ff_pjs_decoder = {
138    .p.name         = "pjs",
139    .p.long_name    = NULL_IF_CONFIG_SMALL("PJS subtitle"),
140    .priv_data_size = sizeof(TextContext),
141    .p.type         = AVMEDIA_TYPE_SUBTITLE,
142    .p.id           = AV_CODEC_ID_PJS,
143    FF_CODEC_DECODE_SUB_CB(text_decode_frame),
144    .init           = linebreak_init,
145    .p.priv_class   = &textsub_decoder_class,
146    .flush          = text_flush,
147    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
148};
149#endif
150
151#if CONFIG_SUBVIEWER1_DECODER
152const FFCodec ff_subviewer1_decoder = {
153    .p.name         = "subviewer1",
154    .p.long_name    = NULL_IF_CONFIG_SMALL("SubViewer1 subtitle"),
155    .priv_data_size = sizeof(TextContext),
156    .p.type         = AVMEDIA_TYPE_SUBTITLE,
157    .p.id           = AV_CODEC_ID_SUBVIEWER1,
158    FF_CODEC_DECODE_SUB_CB(text_decode_frame),
159    .init           = linebreak_init,
160    .p.priv_class   = &textsub_decoder_class,
161    .flush          = text_flush,
162    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
163};
164#endif
165
166#endif /* text subtitles with '|' line break */
167