From 32d05934abc7427bb90380a4c1ab20a15fd7d821 Mon Sep 17 00:00:00 2001 From: Alessandro Ghedini Date: Sun, 13 Apr 2014 14:23:57 +0200 Subject: [PATCH] mp3dec: decode more data from Info header Signed-off-by: Anton Khirnov --- libavformat/avio_internal.h | 2 + libavformat/aviobuf.c | 6 +++ libavformat/mp3dec.c | 103 ++++++++++++++++++++++++++++++++---- 3 files changed, 101 insertions(+), 10 deletions(-) diff --git a/libavformat/avio_internal.h b/libavformat/avio_internal.h index fdc98ec197..a8bcadd38b 100644 --- a/libavformat/avio_internal.h +++ b/libavformat/avio_internal.h @@ -94,6 +94,8 @@ void ffio_init_checksum(AVIOContext *s, unsigned long ffio_get_checksum(AVIOContext *s); unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf, unsigned int len); +unsigned long ff_crcA001_update(unsigned long checksum, const uint8_t *buf, + unsigned int len); /** * Open a write only packetized memory stream with a maximum packet diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c index 0024f9e8b2..cc79146225 100644 --- a/libavformat/aviobuf.c +++ b/libavformat/aviobuf.c @@ -414,6 +414,12 @@ unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf, return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len); } +unsigned long ff_crcA001_update(unsigned long checksum, const uint8_t *buf, + unsigned int len) +{ + return av_crc(av_crc_get_table(AV_CRC_16_ANSI_LE), checksum, buf, len); +} + unsigned long ffio_get_checksum(AVIOContext *s) { s->checksum = s->update_checksum(s->checksum, s->checksum_ptr, diff --git a/libavformat/mp3dec.c b/libavformat/mp3dec.c index 1ab5159982..14d8254f4c 100644 --- a/libavformat/mp3dec.c +++ b/libavformat/mp3dec.c @@ -21,10 +21,12 @@ #include "libavutil/avstring.h" #include "libavutil/intreadwrite.h" +#include "libavutil/crc.h" #include "libavutil/dict.h" #include "libavutil/mathematics.h" #include "avformat.h" #include "internal.h" +#include "avio_internal.h" #include "id3v2.h" #include "id3v1.h" #include "replaygain.h" @@ -128,11 +130,20 @@ static void read_xing_toc(AVFormatContext *s, int64_t filesize, int64_t duration mp3->xing_toc = 1; } - static void mp3_parse_info_tag(AVFormatContext *s, AVStream *st, MPADecodeHeader *c, uint32_t spf) { +#define LAST_BITS(k, n) ((k) & ((1 << (n)) - 1)) +#define MIDDLE_BITS(k, m, n) LAST_BITS((k) >> (m), ((n) - (m))) + + uint16_t crc; uint32_t v; + + char version[10]; + + uint32_t peak = 0; + int32_t r_gain = INT32_MIN, a_gain = INT32_MIN; + MP3DecContext *mp3 = s->priv_data; const int64_t xing_offtbl[2][2] = {{32, 17}, {17,9}}; @@ -140,17 +151,87 @@ static void mp3_parse_info_tag(AVFormatContext *s, AVStream *st, avio_skip(s->pb, xing_offtbl[c->lsf == 1][c->nb_channels == 1]); v = avio_rb32(s->pb); mp3->is_cbr = v == MKBETAG('I', 'n', 'f', 'o'); - if (v == MKBETAG('X', 'i', 'n', 'g') || mp3->is_cbr) { - v = avio_rb32(s->pb); - 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, + if (v != MKBETAG('X', 'i', 'n', 'g') && !mp3->is_cbr) + return; + + v = avio_rb32(s->pb); + 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, (AVRational){spf, c->sample_rate}, st->time_base)); + + /* VBR quality */ + avio_rb32(s->pb); + + /* Encoder short version string */ + memset(version, 0, sizeof(version)); + avio_read(s->pb, version, 9); + + /* Info Tag revision + VBR method */ + avio_r8(s->pb); + + /* Lowpass filter value */ + avio_r8(s->pb); + + /* ReplayGain peak */ + v = avio_rb32(s->pb); + peak = av_rescale(v, 100000, 1 << 23); + + /* Radio ReplayGain */ + v = avio_rb16(s->pb); + + if (MIDDLE_BITS(v, 13, 15) == 1) { + r_gain = MIDDLE_BITS(v, 0, 8) * 10000; + + if (v & (1 << 9)) + r_gain *= -1; + } + + /* Audiophile ReplayGain */ + v = avio_rb16(s->pb); + + if (MIDDLE_BITS(v, 13, 15) == 2) { + a_gain = MIDDLE_BITS(v, 0, 8) * 10000; + + if (v & (1 << 9)) + a_gain *= -1; + } + + /* Encoding flags + ATH Type */ + avio_r8(s->pb); + + /* if ABR {specified bitrate} else {minimal bitrate} */ + avio_r8(s->pb); + + /* Encoder delays */ + avio_rb24(s->pb); + + /* Misc */ + avio_r8(s->pb); + + /* MP3 gain */ + avio_r8(s->pb); + + /* Preset and surround info */ + avio_rb16(s->pb); + + /* Music length */ + avio_rb32(s->pb); + + /* Music CRC */ + avio_rb16(s->pb); + + /* Info Tag CRC */ + crc = ffio_get_checksum(s->pb); + v = avio_rb16(s->pb); + + if (v == crc) { + ff_replaygain_export_raw(st, r_gain, peak, a_gain, 0); + av_dict_set(&st->metadata, "encoder", version, 0); } } @@ -183,6 +264,8 @@ static int mp3_parse_vbr_tags(AVFormatContext *s, AVStream *st, int64_t base) int vbrtag_size = 0; MP3DecContext *mp3 = s->priv_data; + ffio_init_checksum(s->pb, ff_crcA001_update, 0); + v = avio_rb32(s->pb); if(ff_mpa_check_header(v) < 0) return -1;