mirror of
https://git.ffmpeg.org/ffmpeg.git
synced 2024-12-28 18:32:22 +00:00
227 lines
6.9 KiB
C
227 lines
6.9 KiB
C
/*
|
|
* TTML subtitle muxer
|
|
* Copyright (c) 2020 24i
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
/**
|
|
* @file
|
|
* TTML subtitle muxer
|
|
* @see https://www.w3.org/TR/ttml1/
|
|
* @see https://www.w3.org/TR/ttml2/
|
|
* @see https://www.w3.org/TR/ttml-imsc/rec
|
|
*/
|
|
|
|
#include "libavutil/avstring.h"
|
|
#include "avformat.h"
|
|
#include "internal.h"
|
|
#include "mux.h"
|
|
#include "ttmlenc.h"
|
|
#include "libavcodec/ttmlenc.h"
|
|
#include "libavutil/internal.h"
|
|
|
|
enum TTMLPacketType {
|
|
PACKET_TYPE_PARAGRAPH,
|
|
PACKET_TYPE_DOCUMENT,
|
|
};
|
|
|
|
struct TTMLHeaderParameters {
|
|
const char *tt_element_params;
|
|
const char *pre_body_elements;
|
|
};
|
|
|
|
typedef struct TTMLMuxContext {
|
|
enum TTMLPacketType input_type;
|
|
unsigned int document_written;
|
|
} TTMLMuxContext;
|
|
|
|
static const char ttml_header_text[] =
|
|
"<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"
|
|
"<tt\n"
|
|
"%s"
|
|
" xml:lang=\"%s\">\n"
|
|
"%s"
|
|
" <body>\n"
|
|
" <div>\n";
|
|
|
|
static const char ttml_footer_text[] =
|
|
" </div>\n"
|
|
" </body>\n"
|
|
"</tt>\n";
|
|
|
|
static void ttml_write_time(AVIOContext *pb, const char tag[],
|
|
int64_t millisec)
|
|
{
|
|
int64_t sec, min, hour;
|
|
sec = millisec / 1000;
|
|
millisec -= 1000 * sec;
|
|
min = sec / 60;
|
|
sec -= 60 * min;
|
|
hour = min / 60;
|
|
min -= 60 * hour;
|
|
|
|
avio_printf(pb, "%s=\"%02"PRId64":%02"PRId64":%02"PRId64".%03"PRId64"\"",
|
|
tag, hour, min, sec, millisec);
|
|
}
|
|
|
|
static int ttml_set_header_values_from_extradata(
|
|
AVCodecParameters *par, struct TTMLHeaderParameters *header_params)
|
|
{
|
|
size_t additional_data_size =
|
|
par->extradata_size - TTMLENC_EXTRADATA_SIGNATURE_SIZE;
|
|
char *value =
|
|
(char *)par->extradata + TTMLENC_EXTRADATA_SIGNATURE_SIZE;
|
|
size_t value_size = av_strnlen(value, additional_data_size);
|
|
struct TTMLHeaderParameters local_params = { 0 };
|
|
|
|
if (!additional_data_size) {
|
|
// simple case, we don't have to go through local_params and just
|
|
// set default fall-back values (for old extradata format).
|
|
header_params->tt_element_params = TTML_DEFAULT_NAMESPACING;
|
|
header_params->pre_body_elements = "";
|
|
|
|
return 0;
|
|
}
|
|
|
|
if (value_size == additional_data_size ||
|
|
value[value_size] != '\0')
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
local_params.tt_element_params = value;
|
|
|
|
additional_data_size -= value_size + 1;
|
|
value += value_size + 1;
|
|
if (!additional_data_size)
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
value_size = av_strnlen(value, additional_data_size);
|
|
if (value_size == additional_data_size ||
|
|
value[value_size] != '\0')
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
local_params.pre_body_elements = value;
|
|
|
|
*header_params = local_params;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ttml_write_header(AVFormatContext *ctx)
|
|
{
|
|
TTMLMuxContext *ttml_ctx = ctx->priv_data;
|
|
AVStream *st = ctx->streams[0];
|
|
AVIOContext *pb = ctx->pb;
|
|
|
|
const AVDictionaryEntry *lang = av_dict_get(st->metadata, "language", NULL,
|
|
0);
|
|
const char *printed_lang = (lang && lang->value) ? lang->value : "";
|
|
|
|
ttml_ctx->document_written = 0;
|
|
ttml_ctx->input_type = ff_is_ttml_stream_paragraph_based(st->codecpar) ?
|
|
PACKET_TYPE_PARAGRAPH :
|
|
PACKET_TYPE_DOCUMENT;
|
|
|
|
avpriv_set_pts_info(st, 64, 1, 1000);
|
|
|
|
if (ttml_ctx->input_type == PACKET_TYPE_PARAGRAPH) {
|
|
struct TTMLHeaderParameters header_params;
|
|
int ret = ttml_set_header_values_from_extradata(
|
|
st->codecpar, &header_params);
|
|
if (ret < 0) {
|
|
av_log(ctx, AV_LOG_ERROR,
|
|
"Failed to parse TTML header values from extradata: "
|
|
"%s!\n", av_err2str(ret));
|
|
return ret;
|
|
}
|
|
|
|
avio_printf(pb, ttml_header_text,
|
|
header_params.tt_element_params,
|
|
printed_lang,
|
|
header_params.pre_body_elements);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ttml_write_packet(AVFormatContext *ctx, AVPacket *pkt)
|
|
{
|
|
TTMLMuxContext *ttml_ctx = ctx->priv_data;
|
|
AVIOContext *pb = ctx->pb;
|
|
|
|
switch (ttml_ctx->input_type) {
|
|
case PACKET_TYPE_PARAGRAPH:
|
|
// write out a paragraph element with the given contents.
|
|
avio_printf(pb, " <p\n");
|
|
ttml_write_time(pb, " begin", pkt->pts);
|
|
avio_w8(pb, '\n');
|
|
ttml_write_time(pb, " end", pkt->pts + pkt->duration);
|
|
avio_printf(pb, ">");
|
|
avio_write(pb, pkt->data, pkt->size);
|
|
avio_printf(pb, "</p>\n");
|
|
break;
|
|
case PACKET_TYPE_DOCUMENT:
|
|
// dump the given document out as-is.
|
|
if (ttml_ctx->document_written) {
|
|
av_log(ctx, AV_LOG_ERROR,
|
|
"Attempting to write multiple TTML documents into a "
|
|
"single document! The XML specification forbids this "
|
|
"as there has to be a single root tag.\n");
|
|
return AVERROR(EINVAL);
|
|
}
|
|
avio_write(pb, pkt->data, pkt->size);
|
|
ttml_ctx->document_written = 1;
|
|
break;
|
|
default:
|
|
av_log(ctx, AV_LOG_ERROR,
|
|
"Internal error: invalid TTML input packet type: %d!\n",
|
|
ttml_ctx->input_type);
|
|
return AVERROR_BUG;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ttml_write_trailer(AVFormatContext *ctx)
|
|
{
|
|
TTMLMuxContext *ttml_ctx = ctx->priv_data;
|
|
AVIOContext *pb = ctx->pb;
|
|
|
|
if (ttml_ctx->input_type == PACKET_TYPE_PARAGRAPH)
|
|
avio_printf(pb, ttml_footer_text);
|
|
|
|
return 0;
|
|
}
|
|
|
|
const FFOutputFormat ff_ttml_muxer = {
|
|
.p.name = "ttml",
|
|
.p.long_name = NULL_IF_CONFIG_SMALL("TTML subtitle"),
|
|
.p.extensions = "ttml",
|
|
.p.mime_type = "text/ttml",
|
|
.priv_data_size = sizeof(TTMLMuxContext),
|
|
.p.flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS |
|
|
AVFMT_TS_NONSTRICT,
|
|
.p.video_codec = AV_CODEC_ID_NONE,
|
|
.p.audio_codec = AV_CODEC_ID_NONE,
|
|
.p.subtitle_codec = AV_CODEC_ID_TTML,
|
|
.flags_internal = FF_OFMT_FLAG_MAX_ONE_OF_EACH |
|
|
FF_OFMT_FLAG_ONLY_DEFAULT_CODECS,
|
|
.write_header = ttml_write_header,
|
|
.write_packet = ttml_write_packet,
|
|
.write_trailer = ttml_write_trailer,
|
|
};
|