| /* |
| * Copyright (c) 2012-2013 Clément Bœsch <u pkh me> |
| * |
| * 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 "subtitles.h" |
| #include "avio_internal.h" |
| #include "libavutil/avassert.h" |
| #include "libavutil/avstring.h" |
| |
| void ff_text_init_avio(void *s, FFTextReader *r, AVIOContext *pb) |
| { |
| int i; |
| r->pb = pb; |
| r->buf_pos = r->buf_len = 0; |
| r->type = FF_UTF_8; |
| for (i = 0; i < 2; i++) |
| r->buf[r->buf_len++] = avio_r8(r->pb); |
| if (strncmp("\xFF\xFE", r->buf, 2) == 0) { |
| r->type = FF_UTF16LE; |
| r->buf_pos += 2; |
| } else if (strncmp("\xFE\xFF", r->buf, 2) == 0) { |
| r->type = FF_UTF16BE; |
| r->buf_pos += 2; |
| } else { |
| r->buf[r->buf_len++] = avio_r8(r->pb); |
| if (strncmp("\xEF\xBB\xBF", r->buf, 3) == 0) { |
| // UTF8 |
| r->buf_pos += 3; |
| } |
| } |
| if (s && (r->type == FF_UTF16LE || r->type == FF_UTF16BE)) |
| av_log(s, AV_LOG_INFO, |
| "UTF16 is automatically converted to UTF8, do not specify a character encoding\n"); |
| } |
| |
| void ff_text_init_buf(FFTextReader *r, void *buf, size_t size) |
| { |
| memset(&r->buf_pb, 0, sizeof(r->buf_pb)); |
| ffio_init_context(&r->buf_pb, buf, size, 0, NULL, NULL, NULL, NULL); |
| ff_text_init_avio(NULL, r, &r->buf_pb); |
| } |
| |
| int64_t ff_text_pos(FFTextReader *r) |
| { |
| return avio_tell(r->pb) - r->buf_len + r->buf_pos; |
| } |
| |
| int ff_text_r8(FFTextReader *r) |
| { |
| uint32_t val; |
| uint8_t tmp; |
| if (r->buf_pos < r->buf_len) |
| return r->buf[r->buf_pos++]; |
| if (r->type == FF_UTF16LE) { |
| GET_UTF16(val, avio_rl16(r->pb), return 0;) |
| } else if (r->type == FF_UTF16BE) { |
| GET_UTF16(val, avio_rb16(r->pb), return 0;) |
| } else { |
| return avio_r8(r->pb); |
| } |
| if (!val) |
| return 0; |
| r->buf_pos = 0; |
| r->buf_len = 0; |
| PUT_UTF8(val, tmp, r->buf[r->buf_len++] = tmp;) |
| return r->buf[r->buf_pos++]; // buf_len is at least 1 |
| } |
| |
| void ff_text_read(FFTextReader *r, char *buf, size_t size) |
| { |
| for ( ; size > 0; size--) |
| *buf++ = ff_text_r8(r); |
| } |
| |
| int ff_text_eof(FFTextReader *r) |
| { |
| return r->buf_pos >= r->buf_len && avio_feof(r->pb); |
| } |
| |
| int ff_text_peek_r8(FFTextReader *r) |
| { |
| int c; |
| if (r->buf_pos < r->buf_len) |
| return r->buf[r->buf_pos]; |
| c = ff_text_r8(r); |
| if (!avio_feof(r->pb)) { |
| r->buf_pos = 0; |
| r->buf_len = 1; |
| r->buf[0] = c; |
| } |
| return c; |
| } |
| |
| AVPacket *ff_subtitles_queue_insert(FFDemuxSubtitlesQueue *q, |
| const uint8_t *event, size_t len, int merge) |
| { |
| AVPacket *subs, *sub; |
| |
| if (merge && q->nb_subs > 0) { |
| /* merge with previous event */ |
| |
| int old_len; |
| sub = &q->subs[q->nb_subs - 1]; |
| old_len = sub->size; |
| if (av_grow_packet(sub, len) < 0) |
| return NULL; |
| memcpy(sub->data + old_len, event, len); |
| } else { |
| /* new event */ |
| |
| if (q->nb_subs >= INT_MAX/sizeof(*q->subs) - 1) |
| return NULL; |
| subs = av_fast_realloc(q->subs, &q->allocated_size, |
| (q->nb_subs + 1) * sizeof(*q->subs)); |
| if (!subs) |
| return NULL; |
| q->subs = subs; |
| sub = &subs[q->nb_subs]; |
| if (av_new_packet(sub, len) < 0) |
| return NULL; |
| q->nb_subs++; |
| sub->flags |= AV_PKT_FLAG_KEY; |
| sub->pts = sub->dts = 0; |
| memcpy(sub->data, event, len); |
| } |
| return sub; |
| } |
| |
| static int cmp_pkt_sub_ts_pos(const void *a, const void *b) |
| { |
| const AVPacket *s1 = a; |
| const AVPacket *s2 = b; |
| if (s1->pts == s2->pts) |
| return FFDIFFSIGN(s1->pos, s2->pos); |
| return FFDIFFSIGN(s1->pts , s2->pts); |
| } |
| |
| static int cmp_pkt_sub_pos_ts(const void *a, const void *b) |
| { |
| const AVPacket *s1 = a; |
| const AVPacket *s2 = b; |
| if (s1->pos == s2->pos) { |
| if (s1->pts == s2->pts) |
| return 0; |
| return s1->pts > s2->pts ? 1 : -1; |
| } |
| return s1->pos > s2->pos ? 1 : -1; |
| } |
| |
| static void drop_dups(void *log_ctx, FFDemuxSubtitlesQueue *q) |
| { |
| int i, drop = 0; |
| |
| for (i = 1; i < q->nb_subs; i++) { |
| const int last_id = i - 1 - drop; |
| const AVPacket *last = &q->subs[last_id]; |
| |
| if (q->subs[i].pts == last->pts && |
| q->subs[i].duration == last->duration && |
| q->subs[i].stream_index == last->stream_index && |
| !strcmp(q->subs[i].data, last->data)) { |
| |
| av_packet_unref(&q->subs[i]); |
| drop++; |
| } else if (drop) { |
| q->subs[last_id + 1] = q->subs[i]; |
| memset(&q->subs[i], 0, sizeof(q->subs[i])); // for safety |
| } |
| } |
| |
| if (drop) { |
| q->nb_subs -= drop; |
| av_log(log_ctx, AV_LOG_WARNING, "Dropping %d duplicated subtitle events\n", drop); |
| } |
| } |
| |
| void ff_subtitles_queue_finalize(void *log_ctx, FFDemuxSubtitlesQueue *q) |
| { |
| int i; |
| |
| if (!q->nb_subs) |
| return; |
| |
| qsort(q->subs, q->nb_subs, sizeof(*q->subs), |
| q->sort == SUB_SORT_TS_POS ? cmp_pkt_sub_ts_pos |
| : cmp_pkt_sub_pos_ts); |
| for (i = 0; i < q->nb_subs; i++) |
| if (q->subs[i].duration < 0 && i < q->nb_subs - 1) |
| q->subs[i].duration = q->subs[i + 1].pts - q->subs[i].pts; |
| |
| if (!q->keep_duplicates) |
| drop_dups(log_ctx, q); |
| } |
| |
| int ff_subtitles_queue_read_packet(FFDemuxSubtitlesQueue *q, AVPacket *pkt) |
| { |
| AVPacket *sub = q->subs + q->current_sub_idx; |
| int ret; |
| |
| if (q->current_sub_idx == q->nb_subs) |
| return AVERROR_EOF; |
| if ((ret = av_packet_ref(pkt, sub)) < 0) { |
| return ret; |
| } |
| |
| pkt->dts = pkt->pts; |
| q->current_sub_idx++; |
| return 0; |
| } |
| |
| static int search_sub_ts(const FFDemuxSubtitlesQueue *q, int64_t ts) |
| { |
| int s1 = 0, s2 = q->nb_subs - 1; |
| |
| if (s2 < s1) |
| return AVERROR(ERANGE); |
| |
| for (;;) { |
| int mid; |
| |
| if (s1 == s2) |
| return s1; |
| if (s1 == s2 - 1) |
| return q->subs[s1].pts <= q->subs[s2].pts ? s1 : s2; |
| mid = (s1 + s2) / 2; |
| if (q->subs[mid].pts <= ts) |
| s1 = mid; |
| else |
| s2 = mid; |
| } |
| } |
| |
| int ff_subtitles_queue_seek(FFDemuxSubtitlesQueue *q, AVFormatContext *s, int stream_index, |
| int64_t min_ts, int64_t ts, int64_t max_ts, int flags) |
| { |
| if (flags & AVSEEK_FLAG_BYTE) { |
| return AVERROR(ENOSYS); |
| } else if (flags & AVSEEK_FLAG_FRAME) { |
| if (ts < 0 || ts >= q->nb_subs) |
| return AVERROR(ERANGE); |
| q->current_sub_idx = ts; |
| } else { |
| int i, idx = search_sub_ts(q, ts); |
| int64_t ts_selected; |
| |
| if (idx < 0) |
| return idx; |
| for (i = idx; i < q->nb_subs && q->subs[i].pts < min_ts; i++) |
| if (stream_index == -1 || q->subs[i].stream_index == stream_index) |
| idx = i; |
| for (i = idx; i > 0 && q->subs[i].pts > max_ts; i--) |
| if (stream_index == -1 || q->subs[i].stream_index == stream_index) |
| idx = i; |
| |
| ts_selected = q->subs[idx].pts; |
| if (ts_selected < min_ts || ts_selected > max_ts) |
| return AVERROR(ERANGE); |
| |
| /* look back in the latest subtitles for overlapping subtitles */ |
| for (i = idx - 1; i >= 0; i--) { |
| int64_t pts = q->subs[i].pts; |
| if (q->subs[i].duration <= 0 || |
| (stream_index != -1 && q->subs[i].stream_index != stream_index)) |
| continue; |
| if (pts >= min_ts && pts > ts_selected - q->subs[i].duration) |
| idx = i; |
| else |
| break; |
| } |
| |
| /* If the queue is used to store multiple subtitles streams (like with |
| * VobSub) and the stream index is not specified, we need to make sure |
| * to focus on the smallest file position offset for a same timestamp; |
| * queue is ordered by pts and then filepos, so we can take the first |
| * entry for a given timestamp. */ |
| if (stream_index == -1) |
| while (idx > 0 && q->subs[idx - 1].pts == q->subs[idx].pts) |
| idx--; |
| |
| q->current_sub_idx = idx; |
| } |
| return 0; |
| } |
| |
| void ff_subtitles_queue_clean(FFDemuxSubtitlesQueue *q) |
| { |
| int i; |
| |
| for (i = 0; i < q->nb_subs; i++) |
| av_packet_unref(&q->subs[i]); |
| av_freep(&q->subs); |
| q->nb_subs = q->allocated_size = q->current_sub_idx = 0; |
| } |
| |
| int ff_smil_extract_next_text_chunk(FFTextReader *tr, AVBPrint *buf, char *c) |
| { |
| int i = 0; |
| char end_chr; |
| |
| if (!*c) // cached char? |
| *c = ff_text_r8(tr); |
| if (!*c) |
| return 0; |
| |
| end_chr = *c == '<' ? '>' : '<'; |
| do { |
| av_bprint_chars(buf, *c, 1); |
| *c = ff_text_r8(tr); |
| i++; |
| } while (*c != end_chr && *c); |
| if (end_chr == '>') { |
| av_bprint_chars(buf, '>', 1); |
| *c = 0; |
| } |
| return i; |
| } |
| |
| const char *ff_smil_get_attr_ptr(const char *s, const char *attr) |
| { |
| int in_quotes = 0; |
| const size_t len = strlen(attr); |
| |
| while (*s) { |
| while (*s) { |
| if (!in_quotes && av_isspace(*s)) |
| break; |
| in_quotes ^= *s == '"'; // XXX: support escaping? |
| s++; |
| } |
| while (av_isspace(*s)) |
| s++; |
| if (!av_strncasecmp(s, attr, len) && s[len] == '=') |
| return s + len + 1 + (s[len + 1] == '"'); |
| } |
| return NULL; |
| } |
| |
| static inline int is_eol(char c) |
| { |
| return c == '\r' || c == '\n'; |
| } |
| |
| void ff_subtitles_read_text_chunk(FFTextReader *tr, AVBPrint *buf) |
| { |
| char eol_buf[5], last_was_cr = 0; |
| int n = 0, i = 0, nb_eol = 0; |
| |
| av_bprint_clear(buf); |
| |
| for (;;) { |
| char c = ff_text_r8(tr); |
| |
| if (!c) |
| break; |
| |
| /* ignore all initial line breaks */ |
| if (n == 0 && is_eol(c)) |
| continue; |
| |
| /* line break buffering: we don't want to add the trailing \r\n */ |
| if (is_eol(c)) { |
| nb_eol += c == '\n' || last_was_cr; |
| if (nb_eol == 2) |
| break; |
| eol_buf[i++] = c; |
| if (i == sizeof(eol_buf) - 1) |
| break; |
| last_was_cr = c == '\r'; |
| continue; |
| } |
| |
| /* only one line break followed by data: we flush the line breaks |
| * buffer */ |
| if (i) { |
| eol_buf[i] = 0; |
| av_bprintf(buf, "%s", eol_buf); |
| i = nb_eol = 0; |
| } |
| |
| av_bprint_chars(buf, c, 1); |
| n++; |
| } |
| } |
| |
| void ff_subtitles_read_chunk(AVIOContext *pb, AVBPrint *buf) |
| { |
| FFTextReader tr; |
| tr.buf_pos = tr.buf_len = 0; |
| tr.type = 0; |
| tr.pb = pb; |
| ff_subtitles_read_text_chunk(&tr, buf); |
| } |
| |
| ptrdiff_t ff_subtitles_read_line(FFTextReader *tr, char *buf, size_t size) |
| { |
| size_t cur = 0; |
| if (!size) |
| return 0; |
| while (cur + 1 < size) { |
| unsigned char c = ff_text_r8(tr); |
| if (!c) |
| return ff_text_eof(tr) ? cur : AVERROR_INVALIDDATA; |
| if (c == '\r' || c == '\n') |
| break; |
| buf[cur++] = c; |
| buf[cur] = '\0'; |
| } |
| while (ff_text_peek_r8(tr) == '\r') |
| ff_text_r8(tr); |
| if (ff_text_peek_r8(tr) == '\n') |
| ff_text_r8(tr); |
| return cur; |
| } |