| /* |
| * SCC subtitle demuxer |
| * Copyright (c) 2017 Paul B Mahol |
| * |
| * 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 "avformat.h" |
| #include "internal.h" |
| #include "subtitles.h" |
| #include "libavutil/avstring.h" |
| #include "libavutil/bprint.h" |
| #include "libavutil/intreadwrite.h" |
| |
| typedef struct SCCContext { |
| FFDemuxSubtitlesQueue q; |
| } SCCContext; |
| |
| static int scc_probe(const AVProbeData *p) |
| { |
| char buf[18]; |
| FFTextReader tr; |
| |
| ff_text_init_buf(&tr, p->buf, p->buf_size); |
| |
| while (ff_text_peek_r8(&tr) == '\r' || ff_text_peek_r8(&tr) == '\n') |
| ff_text_r8(&tr); |
| |
| ff_text_read(&tr, buf, sizeof(buf)); |
| |
| if (!memcmp(buf, "Scenarist_SCC V1.0", 18)) |
| return AVPROBE_SCORE_MAX; |
| |
| return 0; |
| } |
| |
| static int convert(uint8_t x) |
| { |
| if (x >= 'a') |
| x -= 87; |
| else if (x >= 'A') |
| x -= 55; |
| else |
| x -= '0'; |
| return x; |
| } |
| |
| static int scc_read_header(AVFormatContext *s) |
| { |
| SCCContext *scc = s->priv_data; |
| AVStream *st = avformat_new_stream(s, NULL); |
| char line2[4096], line[4096]; |
| int64_t pos, ts, next_ts = AV_NOPTS_VALUE; |
| ptrdiff_t len; |
| uint8_t out[4096]; |
| FFTextReader tr; |
| |
| ff_text_init_avio(s, &tr, s->pb); |
| |
| if (!st) |
| return AVERROR(ENOMEM); |
| avpriv_set_pts_info(st, 64, 1, 1000); |
| st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE; |
| st->codecpar->codec_id = AV_CODEC_ID_EIA_608; |
| |
| while (!ff_text_eof(&tr) || next_ts == AV_NOPTS_VALUE || line2[0]) { |
| char *saveptr = NULL, *lline; |
| int hh, mm, ss, fs, i; |
| AVPacket *sub; |
| |
| if (next_ts == AV_NOPTS_VALUE) { |
| while (!ff_text_eof(&tr)) { |
| len = ff_subtitles_read_line(&tr, line, sizeof(line)); |
| if (len <= 13) |
| continue; |
| if (!strncmp(line, "Scenarist_SCC V1.0", 18)) |
| continue; |
| if (av_sscanf(line, "%d:%d:%d%*[:;]%d", &hh, &mm, &ss, &fs) == 4) |
| break; |
| } |
| |
| ts = (hh * 3600LL + mm * 60LL + ss) * 1000LL + fs * 33; |
| |
| while (!ff_text_eof(&tr)) { |
| len = ff_subtitles_read_line(&tr, line2, sizeof(line2)); |
| if (len <= 13) |
| continue; |
| |
| if (av_sscanf(line2, "%d:%d:%d%*[:;]%d", &hh, &mm, &ss, &fs) == 4) |
| break; |
| } |
| } else { |
| memmove(line, line2, sizeof(line)); |
| line2[0] = 0; |
| |
| while (!ff_text_eof(&tr)) { |
| len = ff_subtitles_read_line(&tr, line2, sizeof(line2)); |
| if (len <= 13) |
| continue; |
| |
| if (av_sscanf(line2, "%d:%d:%d%*[:;]%d", &hh, &mm, &ss, &fs) == 4) |
| break; |
| } |
| } |
| |
| next_ts = (hh * 3600LL + mm * 60LL + ss) * 1000LL + fs * 33; |
| |
| pos = ff_text_pos(&tr); |
| lline = (char *)&line; |
| lline += 12; |
| |
| for (i = 0; i < 4095; i += 3) { |
| char *ptr = av_strtok(lline, " ", &saveptr); |
| char c1, c2, c3, c4; |
| uint8_t o1, o2; |
| |
| if (!ptr) |
| break; |
| |
| if (av_sscanf(ptr, "%c%c%c%c", &c1, &c2, &c3, &c4) != 4) |
| break; |
| o1 = convert(c2) | (convert(c1) << 4); |
| o2 = convert(c4) | (convert(c3) << 4); |
| |
| lline = NULL; |
| |
| if (i > 12 && o1 == 0x94 && o2 == 0x20 && saveptr && |
| (av_strncasecmp(saveptr, "942f", 4) && !av_strncasecmp(saveptr, "942c", 4))) { |
| |
| out[i] = 0; |
| |
| sub = ff_subtitles_queue_insert(&scc->q, out, i, 0); |
| if (!sub) |
| goto fail; |
| |
| sub->pos = pos; |
| pos += i; |
| sub->pts = ts; |
| sub->duration = i * 11; |
| ts += sub->duration; |
| i = 0; |
| } |
| |
| out[i+0] = 0xfc; |
| out[i+1] = o1; |
| out[i+2] = o2; |
| } |
| |
| out[i] = 0; |
| |
| sub = ff_subtitles_queue_insert(&scc->q, out, i, 0); |
| if (!sub) |
| goto fail; |
| |
| sub->pos = pos; |
| sub->pts = ts; |
| sub->duration = next_ts - ts; |
| ts = next_ts; |
| } |
| |
| ff_subtitles_queue_finalize(s, &scc->q); |
| |
| return 0; |
| fail: |
| ff_subtitles_queue_clean(&scc->q); |
| return AVERROR(ENOMEM); |
| } |
| |
| static int scc_read_packet(AVFormatContext *s, AVPacket *pkt) |
| { |
| SCCContext *scc = s->priv_data; |
| return ff_subtitles_queue_read_packet(&scc->q, pkt); |
| } |
| |
| static int scc_read_seek(AVFormatContext *s, int stream_index, |
| int64_t min_ts, int64_t ts, int64_t max_ts, int flags) |
| { |
| SCCContext *scc = s->priv_data; |
| return ff_subtitles_queue_seek(&scc->q, s, stream_index, |
| min_ts, ts, max_ts, flags); |
| } |
| |
| static int scc_read_close(AVFormatContext *s) |
| { |
| SCCContext *scc = s->priv_data; |
| ff_subtitles_queue_clean(&scc->q); |
| return 0; |
| } |
| |
| AVInputFormat ff_scc_demuxer = { |
| .name = "scc", |
| .long_name = NULL_IF_CONFIG_SMALL("Scenarist Closed Captions"), |
| .priv_data_size = sizeof(SCCContext), |
| .read_probe = scc_probe, |
| .read_header = scc_read_header, |
| .read_packet = scc_read_packet, |
| .read_seek2 = scc_read_seek, |
| .read_close = scc_read_close, |
| .extensions = "scc", |
| }; |