ffmpeg/libavcodec/ass.c

221 lines
8.4 KiB
C

/*
* SSA/ASS common functions
* Copyright (c) 2010 Aurelien Jacobs <aurel@gnuage.org>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avcodec.h"
#include "ass.h"
#include "libavutil/avstring.h"
#include "libavutil/bprint.h"
#include "libavutil/mem.h"
#include "version.h"
int ff_ass_subtitle_header_full(AVCodecContext *avctx,
int play_res_x, int play_res_y,
const char *font, int font_size,
int primary_color, int secondary_color,
int outline_color, int back_color,
int bold, int italic, int underline,
int border_style, int alignment)
{
avctx->subtitle_header = av_asprintf(
"[Script Info]\n"
"; Script generated by FFmpeg/Lavc%s\n"
"ScriptType: v4.00+\n"
"PlayResX: %d\n"
"PlayResY: %d\n"
"ScaledBorderAndShadow: yes\n"
"YCbCr Matrix: None\n"
"\n"
"[V4+ Styles]\n"
/* ASS (v4+) header */
"Format: Name, "
"Fontname, Fontsize, "
"PrimaryColour, SecondaryColour, OutlineColour, BackColour, "
"Bold, Italic, Underline, StrikeOut, "
"ScaleX, ScaleY, "
"Spacing, Angle, "
"BorderStyle, Outline, Shadow, "
"Alignment, MarginL, MarginR, MarginV, "
"Encoding\n"
"Style: "
"Default," /* Name */
"%s,%d," /* Font{name,size} */
"&H%x,&H%x,&H%x,&H%x," /* {Primary,Secondary,Outline,Back}Colour */
"%d,%d,%d,0," /* Bold, Italic, Underline, StrikeOut */
"100,100," /* Scale{X,Y} */
"0,0," /* Spacing, Angle */
"%d,1,0," /* BorderStyle, Outline, Shadow */
"%d,10,10,10," /* Alignment, Margin[LRV] */
"1\n" /* Encoding */
"\n"
"[Events]\n"
"Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text\n",
!(avctx->flags & AV_CODEC_FLAG_BITEXACT) ? AV_STRINGIFY(LIBAVCODEC_VERSION) : "",
play_res_x, play_res_y, font, font_size,
primary_color, secondary_color, outline_color, back_color,
-bold, -italic, -underline, border_style, alignment);
if (!avctx->subtitle_header)
return AVERROR(ENOMEM);
avctx->subtitle_header_size = strlen(avctx->subtitle_header);
return 0;
}
int ff_ass_subtitle_header(AVCodecContext *avctx,
const char *font, int font_size,
int color, int back_color,
int bold, int italic, int underline,
int border_style, int alignment)
{
return ff_ass_subtitle_header_full(avctx,
ASS_DEFAULT_PLAYRESX, ASS_DEFAULT_PLAYRESY,
font, font_size, color, color,
back_color, back_color,
bold, italic, underline,
border_style, alignment);
}
int ff_ass_subtitle_header_default(AVCodecContext *avctx)
{
return ff_ass_subtitle_header(avctx, ASS_DEFAULT_FONT,
ASS_DEFAULT_FONT_SIZE,
ASS_DEFAULT_COLOR,
ASS_DEFAULT_BACK_COLOR,
ASS_DEFAULT_BOLD,
ASS_DEFAULT_ITALIC,
ASS_DEFAULT_UNDERLINE,
ASS_DEFAULT_BORDERSTYLE,
ASS_DEFAULT_ALIGNMENT);
}
char *ff_ass_get_dialog(int readorder, int layer, const char *style,
const char *speaker, const char *text)
{
return av_asprintf("%d,%d,%s,%s,0,0,0,,%s",
readorder, layer, style ? style : "Default",
speaker ? speaker : "", text);
}
int ff_ass_add_rect2(AVSubtitle *sub, const char *dialog,
int readorder, int layer, const char *style,
const char *speaker, unsigned *nb_rect_allocated)
{
AVSubtitleRect **rects = sub->rects, *rect;
char *ass_str;
uint64_t new_nb = 0;
if (sub->num_rects >= UINT_MAX)
return AVERROR(ENOMEM);
if (nb_rect_allocated && *nb_rect_allocated <= sub->num_rects) {
if (sub->num_rects < UINT_MAX / 17 * 16) {
new_nb = sub->num_rects + sub->num_rects/16 + 1;
} else
new_nb = UINT_MAX;
} else if (!nb_rect_allocated)
new_nb = sub->num_rects + 1;
if (new_nb) {
rects = av_realloc_array(rects, new_nb, sizeof(*sub->rects));
if (!rects)
return AVERROR(ENOMEM);
if (nb_rect_allocated)
*nb_rect_allocated = new_nb;
sub->rects = rects;
}
rect = av_mallocz(sizeof(*rect));
if (!rect)
return AVERROR(ENOMEM);
rects[sub->num_rects++] = rect;
rect->type = SUBTITLE_ASS;
ass_str = ff_ass_get_dialog(readorder, layer, style, speaker, dialog);
if (!ass_str)
return AVERROR(ENOMEM);
rect->ass = ass_str;
return 0;
}
int ff_ass_add_rect(AVSubtitle *sub, const char *dialog,
int readorder, int layer, const char *style,
const char *speaker)
{
return ff_ass_add_rect2(sub, dialog, readorder, layer, style, speaker, NULL);
}
void ff_ass_decoder_flush(AVCodecContext *avctx)
{
FFASSDecoderContext *s = avctx->priv_data;
if (!(avctx->flags2 & AV_CODEC_FLAG2_RO_FLUSH_NOOP))
s->readorder = 0;
}
void ff_ass_bprint_text_event(AVBPrint *buf, const char *p, int size,
const char *linebreaks, int keep_ass_markup)
{
const char *p_end = p + size;
for (; p < p_end && *p; p++) {
/* forced custom line breaks, not accounted as "normal" EOL */
if (linebreaks && strchr(linebreaks, *p)) {
av_bprintf(buf, "\\N");
/* cancel curly brackets to avoid bogus override tag blocks
* hiding text. Standard ASS has no character escapes,
* though (only) libass provides \{ and \}.
* Unpaired closing brackets don't need escaping at all though and
* to make the situation less bad in standard ASS insert an empty block
*/
} else if (!keep_ass_markup && *p == '{') {
av_bprintf(buf, "\\{{}");
/* append word-joiner U+2060 as UTF-8 to break up sequences like \N */
} else if (!keep_ass_markup && *p == '\\') {
if (p_end - p <= 3 || strncmp(p + 1, "\xe2\x81\xa0", 3))
av_bprintf(buf, "\\\xe2\x81\xa0");
else
av_bprintf(buf, "\\");
/* some packets might end abruptly (no \0 at the end, like for example
* in some cases of demuxing from a classic video container), some
* might be terminated with \n or \r\n which we have to remove (for
* consistency with those who haven't), and we also have to deal with
* evil cases such as \r at the end of the buffer (and no \0 terminated
* character) */
} else if (p[0] == '\n') {
/* some stuff left so we can insert a line break */
if (p < p_end - 1)
av_bprintf(buf, "\\N");
} else if (p[0] == '\r' && p < p_end - 1 && p[1] == '\n') {
/* \r followed by a \n, we can skip it. We don't insert the \N yet
* because we don't know if it is followed by more text */
continue;
/* finally, a sane character */
} else {
av_bprint_chars(buf, *p, 1);
}
}
}