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-rw-r--r--libavformat/mp3dec.c396
1 files changed, 267 insertions, 129 deletions
diff --git a/libavformat/mp3dec.c b/libavformat/mp3dec.c
index e282218b8b..b45a066686 100644
--- a/libavformat/mp3dec.c
+++ b/libavformat/mp3dec.c
@@ -2,23 +2,24 @@
* MP3 demuxer
* Copyright (c) 2003 Fabrice Bellard
*
- * This file is part of Libav.
+ * This file is part of FFmpeg.
*
- * Libav is free software; you can redistribute it and/or
+ * 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.
*
- * Libav is distributed in the hope that it will be useful,
+ * 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 Libav; if not, write to the Free Software
+ * License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
+#include "libavutil/opt.h"
#include "libavutil/avstring.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/crc.h"
@@ -41,21 +42,37 @@
#define XING_TOC_COUNT 100
-typedef struct MP3DecContext {
+#define SAME_HEADER_MASK \
+ (0xffe00000 | (3 << 17) | (3 << 10) | (3 << 19))
+
+typedef struct {
+ AVClass *class;
+ int64_t filesize;
int xing_toc;
+ int start_pad;
+ int end_pad;
+ int usetoc;
unsigned frames; /* Total number of frames in file */
- unsigned size; /* Total number of bytes in the stream */
+ unsigned header_filesize; /* Total number of bytes in the stream */
int is_cbr;
} MP3DecContext;
+enum CheckRet {
+ CHECK_WRONG_HEADER = -1,
+ CHECK_SEEK_FAILED = -2,
+};
+
+static int check(AVIOContext *pb, int64_t pos, uint32_t *header);
+
/* mp3 read */
static int mp3_read_probe(AVProbeData *p)
{
int max_frames, first_frames = 0;
+ int whole_used = 0;
int frames, ret;
uint32_t header;
- uint8_t *buf, *buf0, *buf2, *end;
+ const uint8_t *buf, *buf0, *buf2, *end;
buf0 = p->buf;
end = p->buf + p->buf_size - sizeof(uint32_t);
@@ -67,7 +84,6 @@ static int mp3_read_probe(AVProbeData *p)
for(; buf < end; buf= buf2+1) {
buf2 = buf;
-
for(frames = 0; buf2 < end; frames++) {
MPADecodeHeader h;
@@ -78,39 +94,22 @@ static int mp3_read_probe(AVProbeData *p)
buf2 += h.frame_size;
}
max_frames = FFMAX(max_frames, frames);
- if(buf == buf0)
+ if(buf == buf0) {
first_frames= frames;
+ if (buf2 == end + sizeof(uint32_t))
+ whole_used = 1;
+ }
}
// keep this in sync with ac3 probe, both need to avoid
// issues with MPEG-files!
- if (first_frames >= 10)
- return AVPROBE_SCORE_EXTENSION + 5;
- if (first_frames >= 4)
- return AVPROBE_SCORE_EXTENSION + 1;
-
- if (max_frames) {
- int pes = 0, i;
- unsigned int code = -1;
-
-#define VIDEO_ID 0x000001e0
-#define AUDIO_ID 0x000001c0
- /* do a search for mpegps headers to be able to properly bias
- * towards mpegps if we detect this stream as both. */
- for (i = 0; i<p->buf_size; i++) {
- code = (code << 8) + p->buf[i];
- if ((code & 0xffffff00) == 0x100) {
- if ((code & 0x1f0) == VIDEO_ID) pes++;
- else if((code & 0x1e0) == AUDIO_ID) pes++;
- }
- }
-
- if (pes)
- max_frames = (max_frames + pes - 1) / pes;
- }
- if (max_frames > 500) return AVPROBE_SCORE_EXTENSION;
- else if (max_frames >= 4) return AVPROBE_SCORE_EXTENSION / 2;
- else if (max_frames >= 1) return 1;
- else return 0;
+ if (first_frames>=7) return AVPROBE_SCORE_EXTENSION + 1;
+ else if(max_frames>200)return AVPROBE_SCORE_EXTENSION;
+ else if(max_frames>=4 && max_frames >= p->buf_size/10000) return AVPROBE_SCORE_EXTENSION / 2;
+ else if(ff_id3v2_match(buf0, ID3v2_DEFAULT_MAGIC) && 2*ff_id3v2_tag_len(buf0) >= p->buf_size)
+ return p->buf_size < PROBE_BUF_MAX ? AVPROBE_SCORE_EXTENSION / 4 : AVPROBE_SCORE_EXTENSION - 2;
+ else if(first_frames > 1 && whole_used) return 5;
+ else if(max_frames>=1 && max_frames >= p->buf_size/10000) return 1;
+ else return 0;
//mpegps_mp3_unrecognized_format.mpg has max_frames=3
}
@@ -118,22 +117,25 @@ static void read_xing_toc(AVFormatContext *s, int64_t filesize, int64_t duration
{
int i;
MP3DecContext *mp3 = s->priv_data;
+ int fast_seek = s->flags & AVFMT_FLAG_FAST_SEEK;
+ int fill_index = (mp3->usetoc || fast_seek) && duration > 0;
if (!filesize &&
!(filesize = avio_size(s->pb))) {
av_log(s, AV_LOG_WARNING, "Cannot determine file size, skipping TOC table.\n");
- return;
+ fill_index = 0;
}
for (i = 0; i < XING_TOC_COUNT; i++) {
uint8_t b = avio_r8(s->pb);
-
- av_add_index_entry(s->streams[0],
+ if (fill_index)
+ av_add_index_entry(s->streams[0],
av_rescale(b, filesize, 256),
av_rescale(i, duration, XING_TOC_COUNT),
0, 0, AVINDEX_KEYFRAME);
}
- mp3->xing_toc = 1;
+ if (fill_index)
+ mp3->xing_toc = 1;
}
static void mp3_parse_info_tag(AVFormatContext *s, AVStream *st,
@@ -143,7 +145,7 @@ static void mp3_parse_info_tag(AVFormatContext *s, AVStream *st,
#define MIDDLE_BITS(k, m, n) LAST_BITS((k) >> (m), ((n) - (m)))
uint16_t crc;
- uint32_t v, delays;
+ uint32_t v;
char version[10];
@@ -151,7 +153,9 @@ static void mp3_parse_info_tag(AVFormatContext *s, AVStream *st,
int32_t r_gain = INT32_MIN, a_gain = INT32_MIN;
MP3DecContext *mp3 = s->priv_data;
- static const int64_t xing_offtbl[2][2] = { { 32, 17 }, { 17, 9 } };
+ static const int64_t xing_offtbl[2][2] = {{32, 17}, {17,9}};
+ uint64_t fsize = avio_size(s->pb);
+ fsize = fsize >= avio_tell(s->pb) ? fsize - avio_tell(s->pb) : 0;
/* Check for Xing / Info tag */
avio_skip(s->pb, xing_offtbl[c->lsf == 1][c->nb_channels == 1]);
@@ -164,12 +168,24 @@ static void mp3_parse_info_tag(AVFormatContext *s, AVStream *st,
if (v & XING_FLAG_FRAMES)
mp3->frames = avio_rb32(s->pb);
if (v & XING_FLAG_SIZE)
- mp3->size = avio_rb32(s->pb);
- if (v & XING_FLAG_TOC && mp3->frames)
- read_xing_toc(s, mp3->size, av_rescale_q(mp3->frames,
+ mp3->header_filesize = avio_rb32(s->pb);
+ if (fsize && mp3->header_filesize) {
+ uint64_t min, delta;
+ min = FFMIN(fsize, mp3->header_filesize);
+ delta = FFMAX(fsize, mp3->header_filesize) - min;
+ if (fsize > mp3->header_filesize && delta > min >> 4) {
+ mp3->frames = 0;
+ av_log(s, AV_LOG_WARNING,
+ "invalid concatenated file detected - using bitrate for duration\n");
+ } else if (delta > min >> 4) {
+ av_log(s, AV_LOG_WARNING,
+ "filesize and duration do not match (growing file?)\n");
+ }
+ }
+ if (v & XING_FLAG_TOC)
+ read_xing_toc(s, mp3->header_filesize, av_rescale_q(mp3->frames,
(AVRational){spf, c->sample_rate},
st->time_base));
-
/* VBR quality */
if (v & XING_FLAC_QSCALE)
avio_rb32(s->pb);
@@ -215,9 +231,25 @@ static void mp3_parse_info_tag(AVFormatContext *s, AVStream *st,
avio_r8(s->pb);
/* Encoder delays */
- delays = avio_rb24(s->pb);
- st->codecpar->initial_padding = delays >> 12;
- st->codecpar->trailing_padding = delays & ((1 << 12) - 1);
+ v= avio_rb24(s->pb);
+ if(AV_RB32(version) == MKBETAG('L', 'A', 'M', 'E')
+ || AV_RB32(version) == MKBETAG('L', 'a', 'v', 'f')
+ || AV_RB32(version) == MKBETAG('L', 'a', 'v', 'c')
+ ) {
+
+ mp3->start_pad = v>>12;
+ mp3-> end_pad = v&4095;
+ st->start_skip_samples = mp3->start_pad + 528 + 1;
+ if (mp3->frames) {
+ st->first_discard_sample = -mp3->end_pad + 528 + 1 + mp3->frames * (int64_t)spf;
+ st->last_discard_sample = mp3->frames * (int64_t)spf;
+ }
+ if (!st->start_time)
+ st->start_time = av_rescale_q(st->start_skip_samples,
+ (AVRational){1, c->sample_rate},
+ st->time_base);
+ av_log(s, AV_LOG_DEBUG, "pad %d %d\n", mp3->start_pad, mp3-> end_pad);
+ }
/* Misc */
avio_r8(s->pb);
@@ -257,7 +289,7 @@ static void mp3_parse_vbri_tag(AVFormatContext *s, AVStream *st, int64_t base)
if (avio_rb16(s->pb) == 1) {
/* skip delay and quality */
avio_skip(s->pb, 4);
- mp3->size = avio_rb32(s->pb);
+ mp3->header_filesize = avio_rb32(s->pb);
mp3->frames = avio_rb32(s->pb);
}
}
@@ -289,12 +321,12 @@ static int mp3_parse_vbr_tags(AVFormatContext *s, AVStream *st, int64_t base)
spf = c.lsf ? 576 : 1152; /* Samples per frame, layer 3 */
mp3->frames = 0;
- mp3->size = 0;
+ mp3->header_filesize = 0;
mp3_parse_info_tag(s, st, &c, spf);
mp3_parse_vbri_tag(s, st, base);
- if (!mp3->frames && !mp3->size)
+ if (!mp3->frames && !mp3->header_filesize)
return -1;
/* Skip the vbr tag frame */
@@ -303,17 +335,22 @@ static int mp3_parse_vbr_tags(AVFormatContext *s, AVStream *st, int64_t base)
if (mp3->frames)
st->duration = av_rescale_q(mp3->frames, (AVRational){spf, c.sample_rate},
st->time_base);
- if (mp3->size && mp3->frames && !mp3->is_cbr)
- st->codecpar->bit_rate = av_rescale(mp3->size, 8 * c.sample_rate, mp3->frames * (int64_t)spf);
+ if (mp3->header_filesize && mp3->frames && !mp3->is_cbr)
+ st->codecpar->bit_rate = av_rescale(mp3->header_filesize, 8 * c.sample_rate, mp3->frames * (int64_t)spf);
return 0;
}
static int mp3_read_header(AVFormatContext *s)
{
+ MP3DecContext *mp3 = s->priv_data;
AVStream *st;
int64_t off;
int ret;
+ int i;
+
+ s->metadata = s->internal->id3v2_meta;
+ s->internal->id3v2_meta = NULL;
st = avformat_new_stream(s, NULL);
if (!st)
@@ -321,17 +358,21 @@ static int mp3_read_header(AVFormatContext *s)
st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
st->codecpar->codec_id = AV_CODEC_ID_MP3;
- st->need_parsing = AVSTREAM_PARSE_FULL;
+ st->need_parsing = AVSTREAM_PARSE_FULL_RAW;
st->start_time = 0;
// lcm of all mp3 sample rates
avpriv_set_pts_info(st, 64, 1, 14112000);
+ s->pb->maxsize = -1;
off = avio_tell(s->pb);
if (!av_dict_get(s->metadata, "", NULL, AV_DICT_IGNORE_SUFFIX))
ff_id3v1_read(s);
+ if(s->pb->seekable)
+ mp3->filesize = avio_size(s->pb);
+
if (mp3_parse_vbr_tags(s, st, off) < 0)
avio_seek(s->pb, off, SEEK_SET);
@@ -339,6 +380,44 @@ static int mp3_read_header(AVFormatContext *s)
if (ret < 0)
return ret;
+ off = avio_tell(s->pb);
+ for (i = 0; i < 64 * 1024; i++) {
+ uint32_t header, header2;
+ int frame_size;
+ if (!(i&1023))
+ ffio_ensure_seekback(s->pb, i + 1024 + 4);
+ frame_size = check(s->pb, off + i, &header);
+ if (frame_size > 0) {
+ ret = avio_seek(s->pb, off, SEEK_SET);
+ if (ret < 0)
+ return ret;
+ ffio_ensure_seekback(s->pb, i + 1024 + frame_size + 4);
+ ret = check(s->pb, off + i + frame_size, &header2);
+ if (ret >= 0 &&
+ (header & SAME_HEADER_MASK) == (header2 & SAME_HEADER_MASK))
+ {
+ av_log(s, i > 0 ? AV_LOG_INFO : AV_LOG_VERBOSE, "Skipping %d bytes of junk at %"PRId64".\n", i, off);
+ ret = avio_seek(s->pb, off + i, SEEK_SET);
+ if (ret < 0)
+ return ret;
+ break;
+ } else if (ret == CHECK_SEEK_FAILED) {
+ av_log(s, AV_LOG_ERROR, "Invalid frame size (%d): Could not seek to %"PRId64".\n", frame_size, off + i + frame_size);
+ return AVERROR(EINVAL);
+ }
+ } else if (frame_size == CHECK_SEEK_FAILED) {
+ av_log(s, AV_LOG_ERROR, "Failed to read frame size: Could not seek to %"PRId64".\n", (int64_t) (i + 1024 + frame_size + 4));
+ return AVERROR(EINVAL);
+ }
+ ret = avio_seek(s->pb, off, SEEK_SET);
+ if (ret < 0)
+ return ret;
+ }
+
+ // the seek index is relative to the end of the xing vbr headers
+ for (i = 0; i < st->nb_index_entries; i++)
+ st->index_entries[i].pos += avio_tell(s->pb);
+
/* the parameters will be extracted from the compressed bitstream */
return 0;
}
@@ -347,112 +426,170 @@ static int mp3_read_header(AVFormatContext *s)
static int mp3_read_packet(AVFormatContext *s, AVPacket *pkt)
{
- int ret;
-
- ret = av_get_packet(s->pb, pkt, MP3_PACKET_SIZE);
- if (ret < 0)
- return ret;
+ MP3DecContext *mp3 = s->priv_data;
+ int ret, size;
+ int64_t pos;
+
+ size= MP3_PACKET_SIZE;
+ pos = avio_tell(s->pb);
+ if(mp3->filesize > ID3v1_TAG_SIZE && pos < mp3->filesize)
+ size= FFMIN(size, mp3->filesize - pos);
+
+ ret= av_get_packet(s->pb, pkt, size);
+ if (ret <= 0) {
+ if(ret<0)
+ return ret;
+ return AVERROR_EOF;
+ }
+ pkt->flags &= ~AV_PKT_FLAG_CORRUPT;
pkt->stream_index = 0;
- if (ret > ID3v1_TAG_SIZE &&
- memcmp(&pkt->data[ret - ID3v1_TAG_SIZE], "TAG", 3) == 0)
- ret -= ID3v1_TAG_SIZE;
-
- /* note: we need to modify the packet size here to handle the last
- packet */
- pkt->size = ret;
return ret;
}
-#define SEEK_PACKETS 4
-#define SEEK_WINDOW (SEEK_PACKETS * MP3_PACKET_SIZE)
+#define SEEK_WINDOW 4096
-/* The toc entry can position to the wrong byte offset, try to pick
- * the closest frame by probing the data in a window of 4 packets.
- */
-
-static int check(AVIOContext *pb, int64_t pos, int64_t *out_pos)
+static int check(AVIOContext *pb, int64_t pos, uint32_t *ret_header)
{
- MPADecodeHeader mh = { 0 };
- int i;
- uint32_t header;
- int64_t off = 0;
-
-
- for (i = 0; i < SEEK_PACKETS; i++) {
- off = avio_seek(pb, pos + mh.frame_size, SEEK_SET);
- if (off < 0)
- break;
-
- header = avio_rb32(pb);
-
-
- if (avpriv_mpegaudio_decode_header(&mh, header))
- break;
- out_pos[i] = off;
- }
-
- return i;
+ int64_t ret = avio_seek(pb, pos, SEEK_SET);
+ uint8_t header_buf[4];
+ unsigned header;
+ MPADecodeHeader sd;
+ if (ret < 0)
+ return CHECK_SEEK_FAILED;
+
+ ret = avio_read(pb, &header_buf[0], 4);
+ /* We should always find four bytes for a valid mpa header. */
+ if (ret < 4)
+ return CHECK_SEEK_FAILED;
+
+ header = AV_RB32(&header_buf[0]);
+ if (ff_mpa_check_header(header) < 0)
+ return CHECK_WRONG_HEADER;
+ if (avpriv_mpegaudio_decode_header(&sd, header) == 1)
+ return CHECK_WRONG_HEADER;
+
+ if (ret_header)
+ *ret_header = header;
+ return sd.frame_size;
}
-static int reposition(AVFormatContext *s, int64_t pos)
+static int64_t mp3_sync(AVFormatContext *s, int64_t target_pos, int flags)
{
- int ret, best_valid = -1;
- int64_t p, best_pos = -1;
-
- for (p = FFMAX(pos - SEEK_WINDOW / 2, 0); p < pos + SEEK_WINDOW / 2; p++) {
- int64_t out_pos[SEEK_PACKETS];
- ret = check(s->pb, p, out_pos);
-
- if (best_valid < ret) {
- int i;
- for (i = 0; i < ret; i++) {
- if (llabs(best_pos - pos) > llabs(out_pos[i] - pos)) {
- best_pos = out_pos[i];
- best_valid = ret;
+ int dir = (flags&AVSEEK_FLAG_BACKWARD) ? -1 : 1;
+ int64_t best_pos;
+ int best_score, i, j;
+ int64_t ret;
+
+ avio_seek(s->pb, FFMAX(target_pos - SEEK_WINDOW, 0), SEEK_SET);
+ ret = avio_seek(s->pb, target_pos, SEEK_SET);
+ if (ret < 0)
+ return ret;
+
+#define MIN_VALID 3
+ best_pos = target_pos;
+ best_score = 999;
+ for(i=0; i<SEEK_WINDOW; i++) {
+ int64_t pos = target_pos + (dir > 0 ? i - SEEK_WINDOW/4 : -i);
+ int64_t candidate = -1;
+ int score = 999;
+
+ if (pos < 0)
+ continue;
+
+ for(j=0; j<MIN_VALID; j++) {
+ ret = check(s->pb, pos, NULL);
+ if(ret < 0) {
+ if (ret == CHECK_WRONG_HEADER) {
+ break;
+ } else if (ret == CHECK_SEEK_FAILED) {
+ av_log(s, AV_LOG_ERROR, "Could not seek to %"PRId64".\n", pos);
+ return AVERROR(EINVAL);
}
}
- if (best_pos == pos && best_valid == SEEK_PACKETS)
+ if ((target_pos - pos)*dir <= 0 && abs(MIN_VALID/2-j) < score) {
+ candidate = pos;
+ score = abs(MIN_VALID/2-j);
+ }
+ pos += ret;
+ }
+ if (best_score > score && j == MIN_VALID) {
+ best_pos = candidate;
+ best_score = score;
+ if(score == 0)
break;
}
}
- if (best_valid <= 0)
- return AVERROR(ENOSYS);
-
- p = avio_seek(s->pb, best_pos, SEEK_SET);
- if (p < 0)
- return p;
-
- return 0;
+ return avio_seek(s->pb, best_pos, SEEK_SET);
}
static int mp3_seek(AVFormatContext *s, int stream_index, int64_t timestamp,
int flags)
{
MP3DecContext *mp3 = s->priv_data;
- AVIndexEntry *ie;
+ AVIndexEntry *ie, ie1;
AVStream *st = s->streams[0];
- int64_t ret = av_index_search_timestamp(st, timestamp, flags);
+ int64_t best_pos;
+ int fast_seek = s->flags & AVFMT_FLAG_FAST_SEEK;
+ int64_t filesize = mp3->header_filesize;
+
+ if (filesize <= 0) {
+ int64_t size = avio_size(s->pb);
+ if (size > 0 && size > s->internal->data_offset)
+ filesize = size - s->internal->data_offset;
+ }
- if (!mp3->xing_toc)
- return AVERROR(ENOSYS);
+ if (mp3->xing_toc && (mp3->usetoc || (fast_seek && !mp3->is_cbr))) {
+ int64_t ret = av_index_search_timestamp(st, timestamp, flags);
- if (ret < 0)
- return ret;
+ // NOTE: The MP3 TOC is not a precise lookup table. Accuracy is worse
+ // for bigger files.
+ av_log(s, AV_LOG_WARNING, "Using MP3 TOC to seek; may be imprecise.\n");
- ie = &st->index_entries[ret];
+ if (ret < 0)
+ return ret;
- ret = reposition(s, ie->pos);
- if (ret < 0)
- return ret;
+ ie = &st->index_entries[ret];
+ } else if (fast_seek && st->duration > 0 && filesize > 0) {
+ if (!mp3->is_cbr)
+ av_log(s, AV_LOG_WARNING, "Using scaling to seek VBR MP3; may be imprecise.\n");
- ff_update_cur_dts(s, st, ie->timestamp);
+ ie = &ie1;
+ timestamp = av_clip64(timestamp, 0, st->duration);
+ ie->timestamp = timestamp;
+ ie->pos = av_rescale(timestamp, filesize, st->duration) + s->internal->data_offset;
+ } else {
+ return -1; // generic index code
+ }
+
+ best_pos = mp3_sync(s, ie->pos, flags);
+ if (best_pos < 0)
+ return best_pos;
+ if (mp3->is_cbr && ie == &ie1 && mp3->frames) {
+ int frame_duration = av_rescale(st->duration, 1, mp3->frames);
+ ie1.timestamp = frame_duration * av_rescale(best_pos - s->internal->data_offset, mp3->frames, mp3->header_filesize);
+ }
+
+ ff_update_cur_dts(s, st, ie->timestamp);
return 0;
}
+static const AVOption options[] = {
+ { "usetoc", "use table of contents", offsetof(MP3DecContext, usetoc), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, AV_OPT_FLAG_DECODING_PARAM},
+ { NULL },
+};
+
+static const AVClass demuxer_class = {
+ .class_name = "mp3",
+ .item_name = av_default_item_name,
+ .option = options,
+ .version = LIBAVUTIL_VERSION_INT,
+ .category = AV_CLASS_CATEGORY_DEMUXER,
+};
+
AVInputFormat ff_mp3_demuxer = {
.name = "mp3",
.long_name = NULL_IF_CONFIG_SMALL("MP2/3 (MPEG audio layer 2/3)"),
@@ -463,4 +600,5 @@ AVInputFormat ff_mp3_demuxer = {
.priv_data_size = sizeof(MP3DecContext),
.flags = AVFMT_GENERIC_INDEX,
.extensions = "mp2,mp3,m2a,mpa", /* XXX: use probe */
+ .priv_class = &demuxer_class,
};
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-06 07:22:23 +0000