/*
* Subtitles converter to SSA/ASS in order to allow special formatting
*
* This file is part of MPlayer.
*
* MPlayer is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* MPlayer is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with MPlayer; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <string.h>
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#include <stdbool.h>
#include <ctype.h>
#include <libavutil/common.h>
#include "common/msg.h"
#include "bstr/bstr.h"
#include "sd.h"
struct line {
char *buf;
int bufsize;
int len;
};
#ifdef __GNUC__
static void append_text(struct line *dst, char *fmt, ...) __attribute__ ((format(printf, 2, 3)));
#endif
static void append_text(struct line *dst, char *fmt, ...)
{
va_list va;
va_start(va, fmt);
int ret = vsnprintf(dst->buf + dst->len, dst->bufsize - dst->len, fmt, va);
if (ret < 0)
goto out;
dst->len += ret;
if (dst->len > dst->bufsize)
dst->len = dst->bufsize;
out:
va_end(va);
}
static void append_text_n(struct line *dst, char *start, size_t length)
{
append_text(dst, "%.*s", (int)length, start);
}
/*
* SubRip
*
* Support basic tags (italic, bold, underline, strike-through)
* and font tag with size, color and face attributes.
*
*/
struct font_tag {
int size;
uint32_t color;
struct bstr face;
bool has_size : 1;
bool has_color : 1;
bool has_face : 1;
};
static const struct tag_conv {
char *from;
char *to;
} subrip_basic_tags[] = {
{"<i>", "{\\i1}"}, {"</i>", "{\\i0}"},
{"<b>", "{\\b1}"}, {"</b>", "{\\b0}"},
{"<u>", "{\\u1}"}, {"</u>", "{\\u0}"},
{"<s>", "{\\s1}"}, {"</s>", "{\\s0}"},
{"}", "\\}"},
{"\r\n", "\\N"}, {"\n", "\\N"}, {"\r", "\\N"},
};
static const struct {
char *s;
uint32_t v;
} subrip_web_colors[] = {
/* Named CSS3 colors in RGB format; a subset of those
at http://www.w3.org/TR/css3-color/#svg-color */
{"aliceblue", 0xF0F8FF},
{"antiquewhite", 0xFAEBD7},
{"aqua", 0x00FFFF},
{"aquamarine", 0x7FFFD4},
{"azure", 0xF0FFFF},
{"beige", 0xF5F5DC},
{"bisque", 0xFFE4C4},
{"black", 0x000000},
{"blanchedalmond", 0xFFEBCD},
{"blue", 0x0000FF},
{"blueviolet", 0x8A2BE2},
{"brown", 0xA52A2A},
{"burlywood", 0xDEB887},
{"cadetblue", 0x5F9EA0},
{"chartreuse", 0x7FFF00},
{"chocolate", 0xD2691E},
{"coral", 0xFF7F50},
{"cornflowerblue", 0x6495ED},
{"cornsilk", 0xFFF8DC},
{"crimson", 0xDC143C},
{"cyan", 0x00FFFF},
{"darkblue", 0x00008B},
{"darkcyan", 0x008B8B},
{"darkgoldenrod", 0xB8860B},
{"darkgray", 0xA9A9A9},
{"darkgreen", 0x006400},
{"darkgrey", 0xA9A9A9},
{"darkkhaki", 0xBDB76B},
{"darkmagenta", 0x8B008B},
{"darkolivegreen", 0x556B2F},
{"darkorange", 0xFF8C00},
{"darkorchid", 0x9932CC},
{"darkred", 0x8B0000},
{"darksalmon", 0xE9967A},
{"darkseagreen", 0x8FBC8F},
{"darkslateblue", 0x483D8B},
{"darkslategray", 0x2F4F4F},
{"darkslategrey", 0x2F4F4F},
{"darkturquoise", 0x00CED1},
{"darkviolet", 0x9400D3},
{"deeppink", 0xFF1493},
{"deepskyblue", 0x00BFFF},
{"dimgray", 0x696969},
{"dimgrey", 0x696969},
{"dodgerblue", 0x1E90FF},
{"firebrick", 0xB22222},
{"floralwhite", 0xFFFAF0},
{"forestgreen", 0x228B22},
{"fuchsia", 0xFF00FF},
{"gainsboro", 0xDCDCDC},
{"ghostwhite", 0xF8F8FF},
{"gold", 0xFFD700},
{"goldenrod", 0xDAA520},
{"gray", 0x808080},
{"green", 0x008000},
{"greenyellow", 0xADFF2F},
{"grey", 0x808080},
{"honeydew", 0xF0FFF0},
{"hotpink", 0xFF69B4},
{"indianred", 0xCD5C5C},
{"indigo", 0x4B0082},
{"ivory", 0xFFFFF0},
{"khaki", 0xF0E68C},
{"lavender", 0xE6E6FA},
{"lavenderblush", 0xFFF0F5},
{"lawngreen", 0x7CFC00},
{"lemonchiffon", 0xFFFACD},
{"lightblue", 0xADD8E6},
{"lightcoral", 0xF08080},
{"lightcyan", 0xE0FFFF},
{"lightgoldenrodyellow", 0xFAFAD2},
{"lightgray", 0xD3D3D3},
{"lightgreen", 0x90EE90},
{"lightgrey", 0xD3D3D3},
{"lightpink", 0xFFB6C1},
{"lightsalmon", 0xFFA07A},
{"lightseagreen", 0x20B2AA},
{"lightskyblue", 0x87CEFA},
{"lightslategray", 0x778899},
{"lightslategrey", 0x778899},
{"lightsteelblue", 0xB0C4DE},
{"lightyellow", 0xFFFFE0},
{"lime", 0x00FF00},
{"limegreen", 0x32CD32},
{"linen", 0xFAF0E6},
{"magenta", 0xFF00FF},
{"maroon", 0x800000},
{"mediumaquamarine", 0x66CDAA},
{"mediumblue", 0x0000CD},
{"mediumorchid", 0xBA55D3},
{"mediumpurple", 0x9370DB},
{"mediumseagreen", 0x3CB371},
{"mediumslateblue", 0x7B68EE},
{"mediumspringgreen", 0x00FA9A},
{"mediumturquoise", 0x48D1CC},
{"mediumvioletred", 0xC71585},
{"midnightblue", 0x191970},
{"mintcream", 0xF5FFFA},
{"mistyrose", 0xFFE4E1},
{"moccasin", 0xFFE4B5},
{"navajowhite", 0xFFDEAD},
{"navy", 0x000080},
{"oldlace", 0xFDF5E6},
{"olive", 0x808000},
{"olivedrab", 0x6B8E23},
{"orange", 0xFFA500},
{"orangered", 0xFF4500},
{"orchid", 0xDA70D6},
{"palegoldenrod", 0xEEE8AA},
{"palegreen", 0x98FB98},
{"paleturquoise", 0xAFEEEE},
{"palevioletred", 0xDB7093},
{"papayawhip", 0xFFEFD5},
{"peachpuff", 0xFFDAB9},
{"peru", 0xCD853F},
{"pink", 0xFFC0CB},
{"plum", 0xDDA0DD},
{"powderblue", 0xB0E0E6},
{"purple", 0x800080},
{"red", 0xFF0000},
{"rosybrown", 0xBC8F8F},
{"royalblue", 0x4169E1},
{"saddlebrown", 0x8B4513},
{"salmon", 0xFA8072},
{"sandybrown", 0xF4A460},
{"seagreen", 0x2E8B57},
{"seashell", 0xFFF5EE},
{"sienna", 0xA0522D},
{"silver", 0xC0C0C0},
{"skyblue", 0x87CEEB},
{"slateblue", 0x6A5ACD},
{"slategray", 0x708090},
{"slategrey", 0x708090},
{"snow", 0xFFFAFA},
{"springgreen", 0x00FF7F},
{"steelblue", 0x4682B4},
{"tan", 0xD2B48C},
{"teal", 0x008080},
{"thistle", 0xD8BFD8},
{"tomato", 0xFF6347},
{"turquoise", 0x40E0D0},
{"violet", 0xEE82EE},
{"wheat", 0xF5DEB3},
{"white", 0xFFFFFF},
{"whitesmoke", 0xF5F5F5},
{"yellow", 0xFFFF00},
{"yellowgreen", 0x9ACD32},
};
#define SUBRIP_MAX_STACKED_FONT_TAGS 16
/* Read the HTML-style attribute starting at *s, and skip *s past the value.
* Set attr and val to the parsed attribute name and value.
* Return 0 on success, or -1 if no valid attribute was found.
*/
static int read_attr(char **s, struct bstr *attr, struct bstr *val)
{
char *eq = strchr(*s, '=');
if (!eq)
return -1;
attr->start = *s;
attr->len = eq - *s;
for (int i = 0; i < attr->len; i++)
if (!isalnum(attr->start[i]))
return -1;
val->start = eq + 1;
bool quoted = val->start[0] == '"';
if (quoted)
val->start++;
unsigned char *end = strpbrk(val->start, quoted ? "\"" : " >");
if (!end)
return -1;
val->len = end - val->start;
*s = end + quoted;
return 0;
}
static void convert_subrip(struct sd *sd, const char *orig,
char *dest, int dest_buffer_size)
{
/* line is not const to avoid warnings with strtol, etc.
* orig content won't be changed */
char *line = (char *)orig;
struct line new_line = {
.buf = dest,
.bufsize = dest_buffer_size,
};
struct font_tag font_stack[SUBRIP_MAX_STACKED_FONT_TAGS + 1];
font_stack[0] = (struct font_tag){0}; // type with all defaults
int sp = 0;
while (*line && new_line.len < new_line.bufsize - 1) {
char *orig_line = line;
for (int i = 0; i < FF_ARRAY_ELEMS(subrip_basic_tags); i++) {
const struct tag_conv *tag = &subrip_basic_tags[i];
int from_len = strlen(tag->from);
if (strncmp(line, tag->from, from_len) == 0) {
append_text(&new_line, "%s", tag->to);
line += from_len;
}
}
if (strncmp(line, "</font>", 7) == 0) {
/* Closing font tag */
line += 7;
if (sp > 0) {
struct font_tag *tag = &font_stack[sp];
struct font_tag *last_tag = &tag[-1];
sp--;
if (tag->has_size) {
if (!last_tag->has_size)
append_text(&new_line, "{\\fs}");
else if (last_tag->size != tag->size)
append_text(&new_line, "{\\fs%d}", last_tag->size);
}
if (tag->has_color) {
if (!last_tag->has_color)
append_text(&new_line, "{\\c}");
else if (last_tag->color != tag->color)
append_text(&new_line, "{\\c&H%06X&}", last_tag->color);
}
if (tag->has_face) {
if (!last_tag->has_face)
append_text(&new_line, "{\\fn}");
else if (bstrcmp(last_tag->face, tag->face) != 0)
append_text(&new_line, "{\\fn%.*s}",
BSTR_P(last_tag->face));
}
}
} else if (strncmp(line, "<font ", 6) == 0
&& sp + 1 < FF_ARRAY_ELEMS(font_stack)) {
/* Opening font tag */
char *potential_font_tag_start = line;
int len_backup = new_line.len;
struct font_tag *tag = &font_stack[sp + 1];
bool has_valid_attr = false;
*tag = tag[-1]; // keep values from previous tag
line += 6;
while (*line && *line != '>') {
if (*line == ' ') {
line++;
continue;
}
struct bstr attr, val;
if (read_attr(&line, &attr, &val) < 0)
break;
if (!bstrcmp0(attr, "size")) {
tag->size = bstrtoll(val, &val, 10);
if (val.len)
break;
append_text(&new_line, "{\\fs%d}", tag->size);
tag->has_size = true;
has_valid_attr = true;
} else if (!bstrcmp0(attr, "color")) {
int found = 0;
// Try to lookup the string in standard web colors
for (int i = 0; i < FF_ARRAY_ELEMS(subrip_web_colors); i++) {
char *color = subrip_web_colors[i].s;
if (bstrcasecmp(val, bstr0(color)) == 0) {
uint32_t xcolor = subrip_web_colors[i].v;
tag->color = ((xcolor & 0xff) << 16)
| (xcolor & 0xff00)
| ((xcolor & 0xff0000) >> 16);
found = 1;
}
}
// If it's not a web color it must be a HEX RGB value
if (!found) {
// Remove the leading '#'
bstr_eatstart(&val, bstr0("#"));
// Sometimes there are two '#'
bstr_eatstart(&val, bstr0("#"));
// Parse RRGGBB format
tag->color = bstrtoll(val, &val, 16) & 0x00ffffff;
if (!val.len) {
tag->color = ((tag->color & 0xff) << 16)
| (tag->color & 0xff00)
| ((tag->color & 0xff0000) >> 16);
found = 1;
}
}
if (found) {
append_text(&new_line, "{\\c&H%06X&}", tag->color);
tag->has_color = true;
} else {
// We didn't find any matching color
MP_WARN(sd, "unknown font color in subtitle: >%s<\n",
orig);
append_text(&new_line, "{\\c}");
}
has_valid_attr = true;
} else if (!bstrcmp0(attr, "face")) {
/* Font face attribute */
tag->face = val;
append_text(&new_line, "{\\fn%.*s}", BSTR_P(tag->face));
tag->has_face = true;
has_valid_attr = true;
} else
MP_WARN(sd, "unrecognized attribute \"%.*s\" in font tag\n",
BSTR_P(attr));
}
if (!has_valid_attr || *line != '>') { /* Not valid font tag */
line = potential_font_tag_start;
new_line.len = len_backup;
} else {
sp++;
line++;
}
} else if (*line == '{') {
char *end = strchr(line, '}');
if (line[1] == '\\' && end) {
// Likely ASS tag, pass them through
// Note that ASS tags like {something\an8} are legal too (i.e.
// the first character after '{' doesn't have to be '\'), but
// consider these fringe cases not worth supporting.
append_text_n(&new_line, line, end - line + 1);
line = end + 1;
} else {
append_text(&new_line, "\\{");
line++;
}
}
/* Tag conversion code didn't match */
if (line == orig_line)
new_line.buf[new_line.len++] = *line++;
}
new_line.buf[new_line.len] = 0;
}
static const char *srt_ass_extradata =
"[Script Info]\n"
"ScriptType: v4.00+\n"
"PlayResX: 384\n"
"PlayResY: 288\n";
static bool supports_format(const char *format)
{
return format && (strcmp(format, "subrip") == 0 ||
strcmp(format, "text") == 0);
}
static int init(struct sd *sd)
{
sd->output_codec = "ass-text";
sd->output_extradata = (char *)srt_ass_extradata;
sd->output_extradata_len = strlen(sd->output_extradata);
return 0;
}
static void decode(struct sd *sd, struct demux_packet *packet)
{
char dest[SD_MAX_LINE_LEN];
// Assume input buffer is padded with 0
convert_subrip(sd, packet->buffer, dest, sizeof(dest));
sd_conv_add_packet(sd, dest, strlen(dest), packet->pts, packet->duration);
}
const struct sd_functions sd_srt = {
.name = "srt",
.supports_format = supports_format,
.init = init,
.decode = decode,
.get_converted = sd_conv_def_get_converted,
.reset = sd_conv_def_reset,
};