diff options
Diffstat (limited to 'libavformat/jacosubdec.c')
| -rw-r--r-- | libavformat/jacosubdec.c | 304 |
1 files changed, 304 insertions, 0 deletions
diff --git a/libavformat/jacosubdec.c b/libavformat/jacosubdec.c new file mode 100644 index 0000000000..30c4f636bd --- /dev/null +++ b/libavformat/jacosubdec.c @@ -0,0 +1,304 @@ +/* + * Copyright (c) 2012 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 + */ + +/** + * @file + * JACOsub subtitle demuxer + * @see http://unicorn.us.com/jacosub/jscripts.html + * @todo Support P[ALETTE] directive. + */ + +#include "avformat.h" +#include "internal.h" +#include "libavcodec/jacosub.h" +#include "libavutil/avstring.h" +#include "libavutil/bprint.h" +#include "libavutil/intreadwrite.h" + +typedef struct { + char *line; ///< null-terminated heap allocated subtitle line + int64_t pos; ///< offset position + int start; ///< timestamp start + int end; ///< timestamp end +} SubEntry; + +typedef struct { + int shift; + unsigned timeres; + SubEntry *subs; ///< subtitles list + int nsub; ///< number of subtitles + int sid; ///< current subtitle +} JACOsubContext; + +static int timed_line(const char *ptr) +{ + char c; + return (sscanf(ptr, "%*u:%*u:%*u.%*u %*u:%*u:%*u.%*u %c", &c) == 1 || + sscanf(ptr, "@%*u @%*u %c", &c) == 1); +} + +static int jacosub_probe(AVProbeData *p) +{ + const char *ptr = p->buf; + const char *ptr_end = p->buf + p->buf_size; + + if (AV_RB24(ptr) == 0xEFBBBF) + ptr += 3; /* skip UTF-8 BOM */ + + while (ptr < ptr_end) { + if (timed_line(ptr)) + return AVPROBE_SCORE_MAX / 2; + while (jss_whitespace(*ptr)) + ptr++; + ptr += strcspn(ptr, "\n") + 1; + } + return 0; +} + +static const char * const cmds[] = { + "CLOCKPAUSE", + "DIRECTIVE", + "FONT", + "HRES", + "INCLUDE", + "PALETTE", + "QUANTIZE", + "RAMP", + "SHIFT", + "TIMERES", +}; + +static int get_jss_cmd(char k) +{ + int i; + + k = av_toupper(k); + for (i = 0; i < FF_ARRAY_ELEMS(cmds); i++) + if (k == cmds[i][0]) + return i; + return -1; +} + +static int jacosub_read_close(AVFormatContext *s) +{ + int i; + JACOsubContext *jacosub = s->priv_data; + + for (i = 0; i < jacosub->nsub; i++) + av_freep(&jacosub->subs[i].line); + jacosub->nsub = 0; + av_freep(&jacosub->subs); + return 0; +} + +static const char *read_ts(JACOsubContext *jacosub, const char *buf, + int *ts_start, int *ts_end) +{ + int len; + unsigned hs, ms, ss, fs; // hours, minutes, seconds, frame start + unsigned he, me, se, fe; // hours, minutes, seconds, frame end + + /* timed format */ + if (sscanf(buf, "%u:%u:%u.%u %u:%u:%u.%u %n", + &hs, &ms, &ss, &fs, + &he, &me, &se, &fe, &len) == 8) { + *ts_start = (hs*3600 + ms*60 + ss) * jacosub->timeres + fs; + *ts_end = (he*3600 + me*60 + se) * jacosub->timeres + fe; + goto shift_and_ret; + } + + /* timestamps format */ + if (sscanf(buf, "@%u @%u %n", ts_start, ts_end, &len) == 2) + goto shift_and_ret; + + return NULL; + +shift_and_ret: + *ts_start = (*ts_start + jacosub->shift) * 100 / jacosub->timeres; + *ts_end = (*ts_end + jacosub->shift) * 100 / jacosub->timeres; + return buf + len; +} + +static int get_shift(int timeres, const char *buf) +{ + int sign = 1; + int a = 0, b = 0, c = 0, d = 0; +#define SSEP "%*1[.:]" + int n = sscanf(buf, "%d"SSEP"%d"SSEP"%d"SSEP"%d", &a, &b, &c, &d); +#undef SSEP + + if (*buf == '-' || a < 0) { + sign = -1; + a = FFABS(a); + } + + switch (n) { + case 4: return sign * ((a*3600 + b*60 + c) * timeres + d); + case 3: return sign * (( a*60 + b) * timeres + c); + case 2: return sign * (( a) * timeres + b); + } + + return 0; +} + +static int cmp_timed_sub(const void *a, const void *b) +{ + return ((const SubEntry*)a)->start - ((const SubEntry*)b)->start; +} + +static int jacosub_read_header(AVFormatContext *s) +{ + AVBPrint header; + AVIOContext *pb = s->pb; + char line[JSS_MAX_LINESIZE]; + JACOsubContext *jacosub = s->priv_data; + int shift_set = 0; // only the first shift matters + int merge_line = 0; + int i; + + AVStream *st = avformat_new_stream(s, NULL); + if (!st) + return AVERROR(ENOMEM); + avpriv_set_pts_info(st, 64, 1, 100); + st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE; + st->codec->codec_id = CODEC_ID_JACOSUB; + + jacosub->timeres = 30; + + av_bprint_init(&header, 1024+FF_INPUT_BUFFER_PADDING_SIZE, 4096); + + while (!url_feof(pb)) { + int cmd_len; + const char *p = line; + int64_t pos = avio_tell(pb); + + ff_get_line(pb, line, sizeof(line)); + + p = jss_skip_whitespace(p); + + /* queue timed line */ + if (merge_line || timed_line(p)) { + SubEntry *subs, *sub; + const int len = strlen(line); + + if (merge_line) { + char *tmp; + const int old_len = strlen(sub->line); + + sub = &subs[jacosub->nsub]; + tmp = av_realloc(sub->line, old_len + len + 1); + if (!tmp) + return AVERROR(ENOMEM); + sub->line = tmp; + strcpy(sub->line + old_len, line); + } else { + subs = av_realloc(jacosub->subs, + sizeof(*jacosub->subs) * (jacosub->nsub+1)); + if (!subs) + return AVERROR(ENOMEM); + jacosub->subs = subs; + sub = &subs[jacosub->nsub]; + sub->pos = pos; + sub->line = av_strdup(line); + if (!sub->line) + return AVERROR(ENOMEM); + } + merge_line = len > 1 && !strcmp(&line[len - 2], "\\\n"); + if (!merge_line) + jacosub->nsub++; + continue; + } + + /* skip all non-compiler commands and focus on the command */ + if (*p != '#') + continue; + p++; + i = get_jss_cmd(p[0]); + if (i == -1) + continue; + + /* trim command + spaces */ + cmd_len = strlen(cmds[i]); + if (av_strncasecmp(p, cmds[i], cmd_len) == 0) + p += cmd_len; + else + p++; + p = jss_skip_whitespace(p); + + /* handle commands which affect the whole script */ + switch (cmds[i][0]) { + case 'S': // SHIFT command affect the whole script... + if (!shift_set) { + jacosub->shift = get_shift(jacosub->timeres, p); + shift_set = 1; + } + av_bprintf(&header, "#S %s", p); + break; + case 'T': // ...but must be placed after TIMERES + jacosub->timeres = strtol(p, NULL, 10); + av_bprintf(&header, "#T %s", p); + break; + } + } + + /* general/essential directives in the extradata */ + av_bprint_finalize(&header, (char **)&st->codec->extradata); + st->codec->extradata_size = header.len + 1; + + /* SHIFT and TIMERES affect the whole script so packet timing can only be + * done in a second pass */ + for (i = 0; i < jacosub->nsub; i++) { + SubEntry *sub = &jacosub->subs[i]; + read_ts(jacosub, sub->line, &sub->start, &sub->end); + } + qsort(jacosub->subs, jacosub->nsub, sizeof(*jacosub->subs), cmp_timed_sub); + + return 0; +} + +static int jacosub_read_packet(AVFormatContext *s, AVPacket *pkt) +{ + int res; + JACOsubContext *jacosub = s->priv_data; + const SubEntry *sub = &jacosub->subs[jacosub->sid++]; + + if (jacosub->sid == jacosub->nsub) + return AVERROR_EOF; + res = av_new_packet(pkt, strlen(sub->line)); + if (res) + return res; + strcpy(pkt->data, sub->line); + pkt->flags |= AV_PKT_FLAG_KEY; + pkt->pos = sub->pos; + pkt->pts = pkt->dts = sub->start; + pkt->duration = sub->end - sub->start; + return 0; +} + +AVInputFormat ff_jacosub_demuxer = { + .name = "jacosub", + .long_name = NULL_IF_CONFIG_SMALL("JACOsub subtitle format"), + .priv_data_size = sizeof(JACOsubContext), + .read_probe = jacosub_probe, + .read_header = jacosub_read_header, + .read_packet = jacosub_read_packet, + .read_close = jacosub_read_close, + .flags = AVFMT_GENERIC_INDEX, +}; |