/* * SSA/ASS demuxer * Copyright (c) 2008 Michael Niedermayer * Copyright (c) 2014 Clément Bœsch * * 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 <stdint.h> #include "avformat.h"#include "demux.h"#include "internal.h"#include "subtitles.h"#include "libavutil/bprint.h" typedef struct ASSContext {    FFDemuxSubtitlesQueue q;    unsigned readorder;} ASSContext; static int ass_probe(const AVProbeData *p){    char buf[13];    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, "[Script Info]", 13))        return AVPROBE_SCORE_MAX;     return 0;} static int read_dialogue(ASSContext *ass, AVBPrint *dst, const uint8_t *p,                         int64_t *start, int *duration){    int pos = 0;    int64_t end;    int hh1, mm1, ss1, ms1;    int hh2, mm2, ss2, ms2;     if (sscanf(p, "Dialogue: %*[^,],%d:%d:%d%*c%d,%d:%d:%d%*c%d,%n",               &hh1, &mm1, &ss1, &ms1,               &hh2, &mm2, &ss2, &ms2, &pos) >= 8 && pos > 0) {         /* This is not part of the sscanf itself in order to handle an actual         * number (which would be the Layer) or the form "Marked=N" (which is         * the old SSA field, now replaced by Layer, and will lead to Layer         * being 0 here). */        const int layer = atoi(p + 10);         end    = (hh2*3600LL + mm2*60LL + ss2) * 100LL + ms2;        *start = (hh1*3600LL + mm1*60LL + ss1) * 100LL + ms1;        *duration = end - *start;         av_bprint_clear(dst);        av_bprintf(dst, "%u,%d,%s", ass->readorder++, layer, p + pos);        if (!av_bprint_is_complete(dst))            return AVERROR(ENOMEM);         /* right strip the buffer */        while (dst->len > 0 &&               dst->str[dst->len - 1] == '\r' ||               dst->str[dst->len - 1] == '\n')            dst->str[--dst->len] = 0;        return 0;    }    return -1;} static int64_t get_line(AVBPrint *buf, FFTextReader *tr){    int64_t pos = ff_text_pos(tr);     av_bprint_clear(buf);    for (;;) {        char c = ff_text_r8(tr);        if (!c)            break;        av_bprint_chars(buf, c, 1);        if (c == '\n')            break;    }    return pos;} static int ass_read_header(AVFormatContext *s){    ASSContext *ass = s->priv_data;    AVBPrint header, line, rline;    int res = 0;    AVStream *st;    FFTextReader tr;    ff_text_init_avio(s, &tr, s->pb);     st = avformat_new_stream(s, NULL);    if (!st)        return AVERROR(ENOMEM);    avpriv_set_pts_info(st, 64, 1, 100);    st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;    st->codecpar->codec_id   = AV_CODEC_ID_ASS;     av_bprint_init(&header, 0, AV_BPRINT_SIZE_UNLIMITED);    av_bprint_init(&line,   0, AV_BPRINT_SIZE_UNLIMITED);    av_bprint_init(&rline,  0, AV_BPRINT_SIZE_UNLIMITED);     ass->q.keep_duplicates = 1;     for (;;) {        int64_t pos = get_line(&line, &tr);        int64_t ts_start = AV_NOPTS_VALUE;        int duration = -1;        AVPacket *sub;         if (!line.str[0]) // EOF            break;         if (read_dialogue(ass, &rline, line.str, &ts_start, &duration) < 0) {            av_bprintf(&header, "%s", line.str);            continue;        }        sub = ff_subtitles_queue_insert_bprint(&ass->q, &rline, 0);        if (!sub) {            res = AVERROR(ENOMEM);            goto end;        }        sub->pos = pos;        sub->pts = ts_start;        sub->duration = duration;    }     res = ff_bprint_to_codecpar_extradata(st->codecpar, &header);    if (res < 0)        goto end;     ff_subtitles_queue_finalize(s, &ass->q); end:    av_bprint_finalize(&header, NULL);    av_bprint_finalize(&line,   NULL);    av_bprint_finalize(&rline,  NULL);    return res;} const FFInputFormat ff_ass_demuxer = {    .p.name         = "ass",    .p.long_name    = NULL_IF_CONFIG_SMALL("SSA (SubStation Alpha) subtitle"),    .flags_internal = FF_INFMT_FLAG_INIT_CLEANUP,    .priv_data_size = sizeof(ASSContext),    .read_probe     = ass_probe,    .read_header    = ass_read_header,    .read_packet    = ff_subtitles_read_packet,    .read_close     = ff_subtitles_read_close,    .read_seek2     = ff_subtitles_read_seek,};