xref: /third_party/ffmpeg/libavcodec/mpl2dec.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 * MPL2 subtitles decoder
24 *
25 * @see http://web.archive.org/web/20090328040233/http://napisy.ussbrowarek.org/mpl2-eng.html
26 */
27
28#include "avcodec.h"
29#include "ass.h"
30#include "codec_internal.h"
31#include "libavutil/bprint.h"
32
33static int mpl2_event_to_ass(AVBPrint *buf, const char *p)
34{
35    if (*p == ' ')
36        p++;
37
38    while (*p) {
39        int got_style = 0;
40
41        while (*p && strchr("/\\_", *p)) {
42            if      (*p == '/')  av_bprintf(buf, "{\\i1}");
43            else if (*p == '\\') av_bprintf(buf, "{\\b1}");
44            else if (*p == '_')  av_bprintf(buf, "{\\u1}");
45            got_style = 1;
46            p++;
47        }
48
49        while (*p && *p != '|') {
50            if (*p != '\r' && *p != '\n')
51                av_bprint_chars(buf, *p, 1);
52            p++;
53        }
54
55        if (*p == '|') {
56            if (got_style)
57                av_bprintf(buf, "{\\r}");
58            av_bprintf(buf, "\\N");
59            p++;
60        }
61    }
62
63    return 0;
64}
65
66static int mpl2_decode_frame(AVCodecContext *avctx, AVSubtitle *sub,
67                             int *got_sub_ptr, const AVPacket *avpkt)
68{
69    int ret = 0;
70    AVBPrint buf;
71    const char *ptr = avpkt->data;
72    FFASSDecoderContext *s = avctx->priv_data;
73
74    av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED);
75    if (ptr && avpkt->size > 0 && *ptr && !mpl2_event_to_ass(&buf, ptr))
76        ret = ff_ass_add_rect(sub, buf.str, s->readorder++, 0, NULL, NULL);
77    av_bprint_finalize(&buf, NULL);
78    if (ret < 0)
79        return ret;
80    *got_sub_ptr = sub->num_rects > 0;
81    return avpkt->size;
82}
83
84const FFCodec ff_mpl2_decoder = {
85    .p.name         = "mpl2",
86    .p.long_name    = NULL_IF_CONFIG_SMALL("MPL2 subtitle"),
87    .p.type         = AVMEDIA_TYPE_SUBTITLE,
88    .p.id           = AV_CODEC_ID_MPL2,
89    FF_CODEC_DECODE_SUB_CB(mpl2_decode_frame),
90    .init           = ff_ass_subtitle_header_default,
91    .flush          = ff_ass_decoder_flush,
92    .priv_data_size = sizeof(FFASSDecoderContext),
93    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
94};
95