FFmpeg/libavcodec/srtdec.c
Andreas Rheinhardt 20f9727018 avcodec/codec_internal: Add FFCodec, hide internal part of AVCodec
Up until now, codec.h contains both public and private parts
of AVCodec. This exposes the internals of AVCodec to users
and leads them into the temptation of actually using them
and forces us to forward-declare structures and types that
users can't use at all.

This commit changes this by adding a new structure FFCodec to
codec_internal.h that extends AVCodec, i.e. contains the public
AVCodec as first member; the private fields of AVCodec are moved
to this structure, leaving codec.h clean.

Reviewed-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-03-21 01:33:09 +01:00

120 lines
4.1 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 "config_components.h"
#include "libavutil/avstring.h"
#include "libavutil/common.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/parseutils.h"
#include "avcodec.h"
#include "ass.h"
#include "codec_internal.h"
#include "htmlsubtitles.h"
static int srt_to_ass(AVCodecContext *avctx, AVBPrint *dst,
const char *in, int x1, int y1, int x2, int y2)
{
if (x1 >= 0 && y1 >= 0) {
/* XXX: here we rescale coordinate assuming they are in DVD resolution
* (720x480) since we don't have anything better */
if (x2 >= 0 && y2 >= 0 && (x2 != x1 || y2 != y1) && x2 >= x1 && y2 >= y1) {
/* text rectangle defined, write the text at the center of the rectangle */
const int cx = x1 + (x2 - x1)/2;
const int cy = y1 + (y2 - y1)/2;
const int scaled_x = cx * (int64_t)ASS_DEFAULT_PLAYRESX / 720;
const int scaled_y = cy * (int64_t)ASS_DEFAULT_PLAYRESY / 480;
av_bprintf(dst, "{\\an5}{\\pos(%d,%d)}", scaled_x, scaled_y);
} else {
/* only the top left corner, assume the text starts in that corner */
const int scaled_x = x1 * (int64_t)ASS_DEFAULT_PLAYRESX / 720;
const int scaled_y = y1 * (int64_t)ASS_DEFAULT_PLAYRESY / 480;
av_bprintf(dst, "{\\an1}{\\pos(%d,%d)}", scaled_x, scaled_y);
}
}
return ff_htmlmarkup_to_ass(avctx, dst, in);
}
static int srt_decode_frame(AVCodecContext *avctx,
void *data, int *got_sub_ptr, AVPacket *avpkt)
{
AVSubtitle *sub = data;
AVBPrint buffer;
int x1 = -1, y1 = -1, x2 = -1, y2 = -1;
int ret;
size_t size;
const uint8_t *p = av_packet_get_side_data(avpkt, AV_PKT_DATA_SUBTITLE_POSITION, &size);
FFASSDecoderContext *s = avctx->priv_data;
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;
av_bprint_init(&buffer, 0, AV_BPRINT_SIZE_UNLIMITED);
ret = srt_to_ass(avctx, &buffer, avpkt->data, x1, y1, x2, y2);
if (ret >= 0)
ret = ff_ass_add_rect(sub, buffer.str, s->readorder++, 0, NULL, NULL);
av_bprint_finalize(&buffer, NULL);
if (ret < 0)
return ret;
*got_sub_ptr = sub->num_rects > 0;
return avpkt->size;
}
#if CONFIG_SRT_DECODER
/* deprecated decoder */
const FFCodec ff_srt_decoder = {
.p.name = "srt",
.p.long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle"),
.p.type = AVMEDIA_TYPE_SUBTITLE,
.p.id = AV_CODEC_ID_SUBRIP,
.init = ff_ass_subtitle_header_default,
.decode = srt_decode_frame,
.flush = ff_ass_decoder_flush,
.priv_data_size = sizeof(FFASSDecoderContext),
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
};
#endif
#if CONFIG_SUBRIP_DECODER
const FFCodec ff_subrip_decoder = {
.p.name = "subrip",
.p.long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle"),
.p.type = AVMEDIA_TYPE_SUBTITLE,
.p.id = AV_CODEC_ID_SUBRIP,
.init = ff_ass_subtitle_header_default,
.decode = srt_decode_frame,
.flush = ff_ass_decoder_flush,
.priv_data_size = sizeof(FFASSDecoderContext),
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
};
#endif