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 * JACOsub subtitle decoder
24 * @see http://unicorn.us.com/jacosub/jscripts.html
25 */
26
27#include <time.h>
28#include "ass.h"
29#include "codec_internal.h"
30#include "jacosub.h"
31#include "libavutil/avstring.h"
32#include "libavutil/bprint.h"
33#include "libavutil/time_internal.h"
34
35#undef time
36
37static int insert_text(AVBPrint *dst, const char *in, const char *arg)
38{
39    av_bprintf(dst, "%s", arg);
40    return 0;
41}
42
43static int insert_datetime(AVBPrint *dst, const char *in, const char *arg)
44{
45    char buf[16] = {0};
46    time_t now = time(0);
47    struct tm ltime;
48
49    localtime_r(&now, &ltime);
50    if (strftime(buf, sizeof(buf), arg, &ltime))
51        av_bprintf(dst, "%s", buf);
52    return 0;
53}
54
55static int insert_color(AVBPrint *dst, const char *in, const char *arg)
56{
57    return 1; // skip id
58}
59
60static int insert_font(AVBPrint *dst, const char *in, const char *arg)
61{
62    return 1; // skip id
63}
64
65static const struct {
66    const char *from;
67    const char *arg;
68    int (*func)(AVBPrint *dst, const char *in, const char *arg);
69} ass_codes_map[] = {
70    {"\\~", "~",        insert_text},       // tilde doesn't need escaping
71    {"~",   "{\\h}",    insert_text},       // hard space
72    {"\\n", "\\N",      insert_text},       // newline
73    {"\\D", "%d %b %Y", insert_datetime},   // current date
74    {"\\T", "%H:%M",    insert_datetime},   // current time
75    {"\\N", "{\\r}",    insert_text},       // reset to default style
76    {"\\I", "{\\i1}",   insert_text},       // italic on
77    {"\\i", "{\\i0}",   insert_text},       // italic off
78    {"\\B", "{\\b1}",   insert_text},       // bold on
79    {"\\b", "{\\b0}",   insert_text},       // bold off
80    {"\\U", "{\\u1}",   insert_text},       // underline on
81    {"\\u", "{\\u0}",   insert_text},       // underline off
82    {"\\C", "",         insert_color},      // TODO: color
83    {"\\F", "",         insert_font},       // TODO: font
84};
85
86enum {
87    ALIGN_VB = 1<<0, // vertical bottom, default
88    ALIGN_VM = 1<<1, // vertical middle
89    ALIGN_VT = 1<<2, // vertical top
90    ALIGN_JC = 1<<3, // justify center, default
91    ALIGN_JL = 1<<4, // justify left
92    ALIGN_JR = 1<<5, // justify right
93};
94
95static void jacosub_to_ass(AVCodecContext *avctx, AVBPrint *dst, const char *src)
96{
97    int i, valign = 0, halign = 0;
98    char c = av_toupper(*src);
99    char directives[128] = {0};
100
101    /* extract the optional directives */
102    if ((c >= 'A' && c <= 'Z') || c == '[') {
103        char *p    = directives;
104        char *pend = directives + sizeof(directives) - 1;
105
106        do *p++ = av_toupper(*src++);
107        while (*src && !jss_whitespace(*src) && p < pend);
108        *p = 0;
109        src = jss_skip_whitespace(src);
110    }
111
112    /* handle directives (TODO: handle more of them, and more reliably) */
113    if      (strstr(directives, "VB")) valign = ALIGN_VB;
114    else if (strstr(directives, "VM")) valign = ALIGN_VM;
115    else if (strstr(directives, "VT")) valign = ALIGN_VT;
116    if      (strstr(directives, "JC")) halign = ALIGN_JC;
117    else if (strstr(directives, "JL")) halign = ALIGN_JL;
118    else if (strstr(directives, "JR")) halign = ALIGN_JR;
119    if (valign || halign) {
120        if (!valign) valign = ALIGN_VB;
121        if (!halign) halign = ALIGN_JC;
122        switch (valign | halign) {
123        case ALIGN_VB | ALIGN_JL: av_bprintf(dst, "{\\an1}"); break; // bottom left
124        case ALIGN_VB | ALIGN_JC: av_bprintf(dst, "{\\an2}"); break; // bottom center
125        case ALIGN_VB | ALIGN_JR: av_bprintf(dst, "{\\an3}"); break; // bottom right
126        case ALIGN_VM | ALIGN_JL: av_bprintf(dst, "{\\an4}"); break; // middle left
127        case ALIGN_VM | ALIGN_JC: av_bprintf(dst, "{\\an5}"); break; // middle center
128        case ALIGN_VM | ALIGN_JR: av_bprintf(dst, "{\\an6}"); break; // middle right
129        case ALIGN_VT | ALIGN_JL: av_bprintf(dst, "{\\an7}"); break; // top left
130        case ALIGN_VT | ALIGN_JC: av_bprintf(dst, "{\\an8}"); break; // top center
131        case ALIGN_VT | ALIGN_JR: av_bprintf(dst, "{\\an9}"); break; // top right
132        }
133    }
134
135    /* process timed line */
136    while (*src && *src != '\n') {
137
138        /* text continue on the next line */
139        if (src[0] == '\\' && src[1] == '\n') {
140            src += 2;
141            while (jss_whitespace(*src))
142                src++;
143            continue;
144        }
145
146        /* special character codes */
147        for (i = 0; i < FF_ARRAY_ELEMS(ass_codes_map); i++) {
148            const char *from = ass_codes_map[i].from;
149            const char *arg  = ass_codes_map[i].arg;
150            size_t codemap_len = strlen(from);
151
152            if (!strncmp(src, from, codemap_len)) {
153                src += codemap_len;
154                src += ass_codes_map[i].func(dst, src, arg);
155                break;
156            }
157        }
158
159        /* simple char copy */
160        if (i == FF_ARRAY_ELEMS(ass_codes_map))
161            av_bprintf(dst, "%c", *src++);
162    }
163}
164
165static int jacosub_decode_frame(AVCodecContext *avctx, AVSubtitle *sub,
166                                int *got_sub_ptr, const AVPacket *avpkt)
167{
168    int ret;
169    const char *ptr = avpkt->data;
170    FFASSDecoderContext *s = avctx->priv_data;
171
172    if (avpkt->size <= 0)
173        goto end;
174
175    if (*ptr) {
176        AVBPrint buffer;
177
178        // skip timers
179        ptr = jss_skip_whitespace(ptr);
180        ptr = strchr(ptr, ' '); if (!ptr) goto end; ptr++;
181        ptr = strchr(ptr, ' '); if (!ptr) goto end; ptr++;
182
183        av_bprint_init(&buffer, JSS_MAX_LINESIZE, JSS_MAX_LINESIZE);
184        jacosub_to_ass(avctx, &buffer, ptr);
185        ret = ff_ass_add_rect(sub, buffer.str, s->readorder++, 0, NULL, NULL);
186        av_bprint_finalize(&buffer, NULL);
187        if (ret < 0)
188            return ret;
189    }
190
191end:
192    *got_sub_ptr = sub->num_rects > 0;
193    return avpkt->size;
194}
195
196const FFCodec ff_jacosub_decoder = {
197    .p.name         = "jacosub",
198    .p.long_name    = NULL_IF_CONFIG_SMALL("JACOsub subtitle"),
199    .p.type         = AVMEDIA_TYPE_SUBTITLE,
200    .p.id           = AV_CODEC_ID_JACOSUB,
201    .init           = ff_ass_subtitle_header_default,
202    FF_CODEC_DECODE_SUB_CB(jacosub_decode_frame),
203    .flush          = ff_ass_decoder_flush,
204    .priv_data_size = sizeof(FFASSDecoderContext),
205    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
206};
207