yading@11: /*
yading@11:  * Copyright (c) 2012 Clément Bœsch
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: /**
yading@11:  * @file
yading@11:  * SubViewer subtitle demuxer
yading@11:  * @see https://en.wikipedia.org/wiki/SubViewer
yading@11:  */
yading@11: 
yading@11: #include "avformat.h"
yading@11: #include "internal.h"
yading@11: #include "subtitles.h"
yading@11: #include "libavcodec/internal.h"
yading@11: #include "libavutil/avstring.h"
yading@11: #include "libavutil/bprint.h"
yading@11: #include "libavutil/intreadwrite.h"
yading@11: 
yading@11: typedef struct {
yading@11:     FFDemuxSubtitlesQueue q;
yading@11: } SubViewerContext;
yading@11: 
yading@11: static int subviewer_probe(AVProbeData *p)
yading@11: {
yading@11:     char c;
yading@11:     const unsigned char *ptr = p->buf;
yading@11: 
yading@11:     if (AV_RB24(ptr) == 0xEFBBBF)
yading@11:         ptr += 3;  /* skip UTF-8 BOM */
yading@11:     if (sscanf(ptr, "%*u:%*u:%*u.%*u,%*u:%*u:%*u.%*u%c", &c) == 1)
yading@11:         return AVPROBE_SCORE_MAX/2;
yading@11:     if (!strncmp(ptr, "[INFORMATION]", 13))
yading@11:         return AVPROBE_SCORE_MAX/3;
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int read_ts(const char *s, int64_t *start, int *duration)
yading@11: {
yading@11:     int64_t end;
yading@11:     int hh1, mm1, ss1, ms1;
yading@11:     int hh2, mm2, ss2, ms2;
yading@11: 
yading@11:     if (sscanf(s, "%u:%u:%u.%u,%u:%u:%u.%u",
yading@11:                &hh1, &mm1, &ss1, &ms1, &hh2, &mm2, &ss2, &ms2) == 8) {
yading@11:         end    = (hh2*3600LL + mm2*60LL + ss2) * 100LL + ms2;
yading@11:         *start = (hh1*3600LL + mm1*60LL + ss1) * 100LL + ms1;
yading@11:         *duration = end - *start;
yading@11:         return 0;
yading@11:     }
yading@11:     return -1;
yading@11: }
yading@11: 
yading@11: static int subviewer_read_header(AVFormatContext *s)
yading@11: {
yading@11:     SubViewerContext *subviewer = s->priv_data;
yading@11:     AVStream *st = avformat_new_stream(s, NULL);
yading@11:     AVBPrint header;
yading@11:     int res = 0, new_event = 1;
yading@11:     int64_t pts_start = AV_NOPTS_VALUE;
yading@11:     int duration = -1;
yading@11:     AVPacket *sub = NULL;
yading@11: 
yading@11:     if (!st)
yading@11:         return AVERROR(ENOMEM);
yading@11:     avpriv_set_pts_info(st, 64, 1, 100);
yading@11:     st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
yading@11:     st->codec->codec_id   = AV_CODEC_ID_SUBVIEWER;
yading@11: 
yading@11:     av_bprint_init(&header, 0, AV_BPRINT_SIZE_UNLIMITED);
yading@11: 
yading@11:     while (!url_feof(s->pb)) {
yading@11:         char line[2048];
yading@11:         int64_t pos = 0;
yading@11:         int len = ff_get_line(s->pb, line, sizeof(line));
yading@11: 
yading@11:         if (!len)
yading@11:             break;
yading@11: 
yading@11:         line[strcspn(line, "\r\n")] = 0;
yading@11: 
yading@11:         if (line[0] == '[' && strncmp(line, "[br]", 4)) {
yading@11: 
yading@11:             /* ignore event style, XXX: add to side_data? */
yading@11:             if (strstr(line, "[COLF]") || strstr(line, "[SIZE]") ||
yading@11:                 strstr(line, "[FONT]") || strstr(line, "[STYLE]"))
yading@11:                 continue;
yading@11: 
yading@11:             if (!st->codec->extradata) { // header not finalized yet
yading@11:                 av_bprintf(&header, "%s\n", line);
yading@11:                 if (!strncmp(line, "[END INFORMATION]", 17) || !strncmp(line, "[SUBTITLE]", 10)) {
yading@11:                     /* end of header */
yading@11:                     res = avpriv_bprint_to_extradata(st->codec, &header);
yading@11:                     if (res < 0)
yading@11:                         goto end;
yading@11:                 } else if (strncmp(line, "[INFORMATION]", 13)) {
yading@11:                     /* assume file metadata at this point */
yading@11:                     int i, j = 0;
yading@11:                     char key[32], value[128];
yading@11: 
yading@11:                     for (i = 1; i < sizeof(key) - 1 && line[i] && line[i] != ']'; i++)
yading@11:                         key[i - 1] = av_tolower(line[i]);
yading@11:                     key[i - 1] = 0;
yading@11: 
yading@11:                     if (line[i] == ']')
yading@11:                         i++;
yading@11:                     while (line[i] == ' ')
yading@11:                         i++;
yading@11:                     while (j < sizeof(value) - 1 && line[i] && line[i] != ']')
yading@11:                         value[j++] = line[i++];
yading@11:                     value[j] = 0;
yading@11: 
yading@11:                     av_dict_set(&s->metadata, key, value, 0);
yading@11:                 }
yading@11:             }
yading@11:         } else if (read_ts(line, &pts_start, &duration) >= 0) {
yading@11:             new_event = 1;
yading@11:             pos = avio_tell(s->pb);
yading@11:         } else if (*line) {
yading@11:             if (!new_event) {
yading@11:                 sub = ff_subtitles_queue_insert(&subviewer->q, "\n", 1, 1);
yading@11:                 if (!sub) {
yading@11:                     res = AVERROR(ENOMEM);
yading@11:                     goto end;
yading@11:                 }
yading@11:             }
yading@11:             sub = ff_subtitles_queue_insert(&subviewer->q, line, strlen(line), !new_event);
yading@11:             if (!sub) {
yading@11:                 res = AVERROR(ENOMEM);
yading@11:                 goto end;
yading@11:             }
yading@11:             if (new_event) {
yading@11:                 sub->pos = pos;
yading@11:                 sub->pts = pts_start;
yading@11:                 sub->duration = duration;
yading@11:             }
yading@11:             new_event = 0;
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     ff_subtitles_queue_finalize(&subviewer->q);
yading@11: 
yading@11: end:
yading@11:     av_bprint_finalize(&header, NULL);
yading@11:     return res;
yading@11: }
yading@11: 
yading@11: static int subviewer_read_packet(AVFormatContext *s, AVPacket *pkt)
yading@11: {
yading@11:     SubViewerContext *subviewer = s->priv_data;
yading@11:     return ff_subtitles_queue_read_packet(&subviewer->q, pkt);
yading@11: }
yading@11: 
yading@11: static int subviewer_read_seek(AVFormatContext *s, int stream_index,
yading@11:                                int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
yading@11: {
yading@11:     SubViewerContext *subviewer = s->priv_data;
yading@11:     return ff_subtitles_queue_seek(&subviewer->q, s, stream_index,
yading@11:                                    min_ts, ts, max_ts, flags);
yading@11: }
yading@11: 
yading@11: static int subviewer_read_close(AVFormatContext *s)
yading@11: {
yading@11:     SubViewerContext *subviewer = s->priv_data;
yading@11:     ff_subtitles_queue_clean(&subviewer->q);
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: AVInputFormat ff_subviewer_demuxer = {
yading@11:     .name           = "subviewer",
yading@11:     .long_name      = NULL_IF_CONFIG_SMALL("SubViewer subtitle format"),
yading@11:     .priv_data_size = sizeof(SubViewerContext),
yading@11:     .read_probe     = subviewer_probe,
yading@11:     .read_header    = subviewer_read_header,
yading@11:     .read_packet    = subviewer_read_packet,
yading@11:     .read_seek2     = subviewer_read_seek,
yading@11:     .read_close     = subviewer_read_close,
yading@11:     .extensions     = "sub",
yading@11: };