mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-02 03:06:28 +02:00
c27b3816e4
The SRT format should never have outputted CODEC_ID_SRT packets in the first place: SRT is a subtitle format containing SubRip text markup events. The timing information is part of the format, not the codec, and thus CODEC_ID_SRT should not exist. Creating packets with the timing information within the payload only leads to problem (such as remuxing with timing alteration not working), especially when the SubRip markup is being used in container like Matroska in addition to this standalone SRT format. The main reason the timing line was included in those CODEC_ID_SRT packets is likely because it contained extra information (the event position) the codec actually needs. This issue is solved by using the AV_PKT_DATA_SUBTITLE_POSITION side data type.
281 lines
11 KiB
C
281 lines
11 KiB
C
/*
|
|
* SubRip subtitle decoder
|
|
* 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 "libavutil/avstring.h"
|
|
#include "libavutil/common.h"
|
|
#include "libavutil/intreadwrite.h"
|
|
#include "libavutil/parseutils.h"
|
|
#include "avcodec.h"
|
|
#include "ass.h"
|
|
|
|
static int html_color_parse(AVCodecContext *avctx, const char *str)
|
|
{
|
|
uint8_t rgba[4];
|
|
if (av_parse_color(rgba, str, strcspn(str, "\" >"), avctx) < 0)
|
|
return -1;
|
|
return rgba[0] | rgba[1] << 8 | rgba[2] << 16;
|
|
}
|
|
|
|
enum {
|
|
PARAM_UNKNOWN = -1,
|
|
PARAM_SIZE,
|
|
PARAM_COLOR,
|
|
PARAM_FACE,
|
|
PARAM_NUMBER
|
|
};
|
|
|
|
typedef struct {
|
|
char tag[128];
|
|
char param[PARAM_NUMBER][128];
|
|
} SrtStack;
|
|
|
|
static const char *srt_to_ass(AVCodecContext *avctx, char *out, char *out_end,
|
|
const char *in, int x1, int y1, int x2, int y2)
|
|
{
|
|
char c, *param, buffer[128], tmp[128];
|
|
int len, tag_close, sptr = 1, line_start = 1, an = 0, end = 0;
|
|
SrtStack stack[16];
|
|
|
|
stack[0].tag[0] = 0;
|
|
strcpy(stack[0].param[PARAM_SIZE], "{\\fs}");
|
|
strcpy(stack[0].param[PARAM_COLOR], "{\\c}");
|
|
strcpy(stack[0].param[PARAM_FACE], "{\\fn}");
|
|
|
|
if (x1 >= 0 && y1 >= 0) {
|
|
if (x2 >= 0 && y2 >= 0 && (x2 != x1 || y2 != y1))
|
|
snprintf(out, out_end-out,
|
|
"{\\an1}{\\move(%d,%d,%d,%d)}", x1, y1, x2, y2);
|
|
else
|
|
snprintf(out, out_end-out, "{\\an1}{\\pos(%d,%d)}", x1, y1);
|
|
out += strlen(out);
|
|
}
|
|
|
|
for (; out < out_end && !end && *in; in++) {
|
|
switch (*in) {
|
|
case '\r':
|
|
break;
|
|
case '\n':
|
|
if (line_start) {
|
|
end = 1;
|
|
break;
|
|
}
|
|
while (out[-1] == ' ')
|
|
out--;
|
|
snprintf(out, out_end-out, "\\N");
|
|
if(out<out_end) out += strlen(out);
|
|
line_start = 1;
|
|
break;
|
|
case ' ':
|
|
if (!line_start)
|
|
*out++ = *in;
|
|
break;
|
|
case '{': /* skip all {\xxx} substrings except for {\an%d}
|
|
and all microdvd like styles such as {Y:xxx} */
|
|
an += sscanf(in, "{\\an%*1u}%c", &c) == 1;
|
|
if ((an != 1 && sscanf(in, "{\\%*[^}]}%n%c", &len, &c) > 0) ||
|
|
sscanf(in, "{%*1[CcFfoPSsYy]:%*[^}]}%n%c", &len, &c) > 0) {
|
|
in += len - 1;
|
|
} else
|
|
*out++ = *in;
|
|
break;
|
|
case '<':
|
|
tag_close = in[1] == '/';
|
|
if (sscanf(in+tag_close+1, "%127[^>]>%n%c", buffer, &len,&c) >= 2) {
|
|
if ((param = strchr(buffer, ' ')))
|
|
*param++ = 0;
|
|
if ((!tag_close && sptr < FF_ARRAY_ELEMS(stack)) ||
|
|
( tag_close && sptr > 0 && !strcmp(stack[sptr-1].tag, buffer))) {
|
|
int i, j, unknown = 0;
|
|
in += len + tag_close;
|
|
if (!tag_close)
|
|
memset(stack+sptr, 0, sizeof(*stack));
|
|
if (!strcmp(buffer, "font")) {
|
|
if (tag_close) {
|
|
for (i=PARAM_NUMBER-1; i>=0; i--)
|
|
if (stack[sptr-1].param[i][0])
|
|
for (j=sptr-2; j>=0; j--)
|
|
if (stack[j].param[i][0]) {
|
|
snprintf(out, out_end-out,
|
|
"%s", stack[j].param[i]);
|
|
if(out<out_end) out += strlen(out);
|
|
break;
|
|
}
|
|
} else {
|
|
while (param) {
|
|
if (!strncmp(param, "size=", 5)) {
|
|
unsigned font_size;
|
|
param += 5 + (param[5] == '"');
|
|
if (sscanf(param, "%u", &font_size) == 1) {
|
|
snprintf(stack[sptr].param[PARAM_SIZE],
|
|
sizeof(stack[0].param[PARAM_SIZE]),
|
|
"{\\fs%u}", font_size);
|
|
}
|
|
} else if (!strncmp(param, "color=", 6)) {
|
|
param += 6 + (param[6] == '"');
|
|
snprintf(stack[sptr].param[PARAM_COLOR],
|
|
sizeof(stack[0].param[PARAM_COLOR]),
|
|
"{\\c&H%X&}",
|
|
html_color_parse(avctx, param));
|
|
} else if (!strncmp(param, "face=", 5)) {
|
|
param += 5 + (param[5] == '"');
|
|
len = strcspn(param,
|
|
param[-1] == '"' ? "\"" :" ");
|
|
av_strlcpy(tmp, param,
|
|
FFMIN(sizeof(tmp), len+1));
|
|
param += len;
|
|
snprintf(stack[sptr].param[PARAM_FACE],
|
|
sizeof(stack[0].param[PARAM_FACE]),
|
|
"{\\fn%s}", tmp);
|
|
}
|
|
if ((param = strchr(param, ' ')))
|
|
param++;
|
|
}
|
|
for (i=0; i<PARAM_NUMBER; i++)
|
|
if (stack[sptr].param[i][0]) {
|
|
snprintf(out, out_end-out,
|
|
"%s", stack[sptr].param[i]);
|
|
if(out<out_end) out += strlen(out);
|
|
}
|
|
}
|
|
} else if (!buffer[1] && strspn(buffer, "bisu") == 1) {
|
|
snprintf(out, out_end-out,
|
|
"{\\%c%d}", buffer[0], !tag_close);
|
|
if(out<out_end) out += strlen(out);
|
|
} else {
|
|
unknown = 1;
|
|
snprintf(tmp, sizeof(tmp), "</%s>", buffer);
|
|
}
|
|
if (tag_close) {
|
|
sptr--;
|
|
} else if (unknown && !strstr(in, tmp)) {
|
|
in -= len + tag_close;
|
|
*out++ = *in;
|
|
} else
|
|
av_strlcpy(stack[sptr++].tag, buffer,
|
|
sizeof(stack[0].tag));
|
|
break;
|
|
}
|
|
}
|
|
default:
|
|
*out++ = *in;
|
|
break;
|
|
}
|
|
if (*in != ' ' && *in != '\r' && *in != '\n')
|
|
line_start = 0;
|
|
}
|
|
|
|
out = FFMIN(out, out_end-3);
|
|
while (!strncmp(out-2, "\\N", 2))
|
|
out -= 2;
|
|
while (out[-1] == ' ')
|
|
out--;
|
|
snprintf(out, out_end-out, "\r\n");
|
|
return in;
|
|
}
|
|
|
|
static const char *read_ts(const char *buf, int *ts_start, int *ts_end,
|
|
int *x1, int *y1, int *x2, int *y2)
|
|
{
|
|
int i, hs, ms, ss, he, me, se;
|
|
|
|
for (i=0; i<2; i++) {
|
|
/* try to read timestamps in either the first or second line */
|
|
int c = sscanf(buf, "%d:%2d:%2d%*1[,.]%3d --> %d:%2d:%2d%*1[,.]%3d"
|
|
"%*[ ]X1:%u X2:%u Y1:%u Y2:%u",
|
|
&hs, &ms, &ss, ts_start, &he, &me, &se, ts_end,
|
|
x1, x2, y1, y2);
|
|
buf += strcspn(buf, "\n") + 1;
|
|
if (c >= 8) {
|
|
*ts_start = 100*(ss + 60*(ms + 60*hs)) + *ts_start/10;
|
|
*ts_end = 100*(se + 60*(me + 60*he)) + *ts_end /10;
|
|
return buf;
|
|
}
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static int srt_decode_frame(AVCodecContext *avctx,
|
|
void *data, int *got_sub_ptr, AVPacket *avpkt)
|
|
{
|
|
AVSubtitle *sub = data;
|
|
int ts_start, ts_end, x1 = -1, y1 = -1, x2 = -1, y2 = -1;
|
|
char buffer[2048];
|
|
const char *ptr = avpkt->data;
|
|
const char *end = avpkt->data + avpkt->size;
|
|
int size;
|
|
const uint8_t *p = av_packet_get_side_data(avpkt, AV_PKT_DATA_SUBTITLE_POSITION, &size);
|
|
|
|
if (p && size == 16) {
|
|
x1 = AV_RL32(p );
|
|
y1 = AV_RL32(p + 4);
|
|
x2 = AV_RL32(p + 8);
|
|
y2 = AV_RL32(p + 12);
|
|
}
|
|
|
|
if (avpkt->size <= 0)
|
|
return avpkt->size;
|
|
|
|
while (ptr < end && *ptr) {
|
|
if (avctx->codec->id == CODEC_ID_SRT) {
|
|
ptr = read_ts(ptr, &ts_start, &ts_end, &x1, &y1, &x2, &y2);
|
|
if (!ptr)
|
|
break;
|
|
} else {
|
|
// Do final divide-by-10 outside rescale to force rounding down.
|
|
ts_start = av_rescale_q(avpkt->pts,
|
|
avctx->time_base,
|
|
(AVRational){1,100});
|
|
ts_end = av_rescale_q(avpkt->pts + avpkt->duration,
|
|
avctx->time_base,
|
|
(AVRational){1,100});
|
|
}
|
|
ptr = srt_to_ass(avctx, buffer, buffer+sizeof(buffer), ptr,
|
|
x1, y1, x2, y2);
|
|
ff_ass_add_rect(sub, buffer, ts_start, ts_end-ts_start, 0);
|
|
}
|
|
|
|
*got_sub_ptr = sub->num_rects > 0;
|
|
return avpkt->size;
|
|
}
|
|
|
|
#if CONFIG_SRT_DECODER
|
|
/* deprecated decoder */
|
|
AVCodec ff_srt_decoder = {
|
|
.name = "srt",
|
|
.long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle with embedded timing"),
|
|
.type = AVMEDIA_TYPE_SUBTITLE,
|
|
.id = AV_CODEC_ID_SRT,
|
|
.init = ff_ass_subtitle_header_default,
|
|
.decode = srt_decode_frame,
|
|
};
|
|
#endif
|
|
|
|
#if CONFIG_SUBRIP_DECODER
|
|
AVCodec ff_subrip_decoder = {
|
|
.name = "subrip",
|
|
.long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle"),
|
|
.type = AVMEDIA_TYPE_SUBTITLE,
|
|
.id = AV_CODEC_ID_SUBRIP,
|
|
.init = ff_ass_subtitle_header_default,
|
|
.decode = srt_decode_frame,
|
|
};
|
|
#endif
|