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-rw-r--r--src/decoder/plugins/MadDecoderPlugin.cxx1104
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diff --git a/src/decoder/plugins/MadDecoderPlugin.cxx b/src/decoder/plugins/MadDecoderPlugin.cxx
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+++ b/src/decoder/plugins/MadDecoderPlugin.cxx
@@ -0,0 +1,1104 @@
+/*
+ * Copyright (C) 2003-2014 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+#include "MadDecoderPlugin.hxx"
+#include "../DecoderAPI.hxx"
+#include "input/InputStream.hxx"
+#include "config/ConfigGlobal.hxx"
+#include "tag/TagId3.hxx"
+#include "tag/TagRva2.hxx"
+#include "tag/TagHandler.hxx"
+#include "tag/ReplayGain.hxx"
+#include "tag/MixRamp.hxx"
+#include "CheckAudioFormat.hxx"
+#include "util/StringUtil.hxx"
+#include "util/ASCII.hxx"
+#include "util/Error.hxx"
+#include "util/Domain.hxx"
+#include "Log.hxx"
+
+#include <mad.h>
+
+#ifdef HAVE_ID3TAG
+#include <id3tag.h>
+#endif
+
+#include <assert.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+static constexpr unsigned long FRAMES_CUSHION = 2000;
+
+enum mp3_action {
+ DECODE_SKIP = -3,
+ DECODE_BREAK = -2,
+ DECODE_CONT = -1,
+ DECODE_OK = 0
+};
+
+enum muteframe {
+ MUTEFRAME_NONE,
+ MUTEFRAME_SKIP,
+ MUTEFRAME_SEEK
+};
+
+/* the number of samples of silence the decoder inserts at start */
+static constexpr unsigned DECODERDELAY = 529;
+
+static constexpr bool DEFAULT_GAPLESS_MP3_PLAYBACK = true;
+
+static constexpr Domain mad_domain("mad");
+
+static bool gapless_playback;
+
+gcc_const
+static SongTime
+ToSongTime(mad_timer_t t)
+{
+ return SongTime::FromMS(mad_timer_count(t, MAD_UNITS_MILLISECONDS));
+}
+
+static inline int32_t
+mad_fixed_to_24_sample(mad_fixed_t sample)
+{
+ static constexpr unsigned bits = 24;
+ static constexpr mad_fixed_t MIN = -MAD_F_ONE;
+ static constexpr mad_fixed_t MAX = MAD_F_ONE - 1;
+
+ /* round */
+ sample = sample + (1L << (MAD_F_FRACBITS - bits));
+
+ /* clip */
+ if (gcc_unlikely(sample > MAX))
+ sample = MAX;
+ else if (gcc_unlikely(sample < MIN))
+ sample = MIN;
+
+ /* quantize */
+ return sample >> (MAD_F_FRACBITS + 1 - bits);
+}
+
+static void
+mad_fixed_to_24_buffer(int32_t *dest, const struct mad_synth *synth,
+ unsigned int start, unsigned int end,
+ unsigned int num_channels)
+{
+ for (unsigned i = start; i < end; ++i)
+ for (unsigned c = 0; c < num_channels; ++c)
+ *dest++ = mad_fixed_to_24_sample(synth->pcm.samples[c][i]);
+}
+
+static bool
+mp3_plugin_init(gcc_unused const config_param &param)
+{
+ gapless_playback = config_get_bool(CONF_GAPLESS_MP3_PLAYBACK,
+ DEFAULT_GAPLESS_MP3_PLAYBACK);
+ return true;
+}
+
+struct MadDecoder {
+ static constexpr size_t READ_BUFFER_SIZE = 40960;
+ static constexpr size_t MP3_DATA_OUTPUT_BUFFER_SIZE = 2048;
+
+ struct mad_stream stream;
+ struct mad_frame frame;
+ struct mad_synth synth;
+ mad_timer_t timer;
+ unsigned char input_buffer[READ_BUFFER_SIZE];
+ int32_t output_buffer[MP3_DATA_OUTPUT_BUFFER_SIZE];
+ SignedSongTime total_time;
+ SongTime elapsed_time;
+ SongTime seek_time;
+ enum muteframe mute_frame;
+ long *frame_offsets;
+ mad_timer_t *times;
+ unsigned long highest_frame;
+ unsigned long max_frames;
+ unsigned long current_frame;
+ unsigned int drop_start_frames;
+ unsigned int drop_end_frames;
+ unsigned int drop_start_samples;
+ unsigned int drop_end_samples;
+ bool found_replay_gain;
+ bool found_first_frame;
+ bool decoded_first_frame;
+ unsigned long bit_rate;
+ Decoder *const decoder;
+ InputStream &input_stream;
+ enum mad_layer layer;
+
+ MadDecoder(Decoder *decoder, InputStream &input_stream);
+ ~MadDecoder();
+
+ bool Seek(long offset);
+ bool FillBuffer();
+ void ParseId3(size_t tagsize, Tag **mpd_tag);
+ enum mp3_action DecodeNextFrameHeader(Tag **tag);
+ enum mp3_action DecodeNextFrame();
+
+ gcc_pure
+ offset_type ThisFrameOffset() const;
+
+ gcc_pure
+ offset_type RestIncludingThisFrame() const;
+
+ /**
+ * Attempt to calulcate the length of the song from filesize
+ */
+ void FileSizeToSongLength();
+
+ bool DecodeFirstFrame(Tag **tag);
+
+ gcc_pure
+ long TimeToFrame(SongTime t) const;
+
+ void UpdateTimerNextFrame();
+
+ /**
+ * Sends the synthesized current frame via decoder_data().
+ */
+ DecoderCommand SendPCM(unsigned i, unsigned pcm_length);
+
+ /**
+ * Synthesize the current frame and send it via
+ * decoder_data().
+ */
+ DecoderCommand SyncAndSend();
+
+ bool Read();
+};
+
+MadDecoder::MadDecoder(Decoder *_decoder,
+ InputStream &_input_stream)
+ :mute_frame(MUTEFRAME_NONE),
+ frame_offsets(nullptr),
+ times(nullptr),
+ highest_frame(0), max_frames(0), current_frame(0),
+ drop_start_frames(0), drop_end_frames(0),
+ drop_start_samples(0), drop_end_samples(0),
+ found_replay_gain(false),
+ found_first_frame(false), decoded_first_frame(false),
+ decoder(_decoder), input_stream(_input_stream),
+ layer(mad_layer(0))
+{
+ mad_stream_init(&stream);
+ mad_stream_options(&stream, MAD_OPTION_IGNORECRC);
+ mad_frame_init(&frame);
+ mad_synth_init(&synth);
+ mad_timer_reset(&timer);
+}
+
+inline bool
+MadDecoder::Seek(long offset)
+{
+ Error error;
+ if (!input_stream.LockSeek(offset, error))
+ return false;
+
+ mad_stream_buffer(&stream, input_buffer, 0);
+ stream.error = MAD_ERROR_NONE;
+
+ return true;
+}
+
+inline bool
+MadDecoder::FillBuffer()
+{
+ size_t remaining, length;
+ unsigned char *dest;
+
+ if (stream.next_frame != nullptr) {
+ remaining = stream.bufend - stream.next_frame;
+ memmove(input_buffer, stream.next_frame, remaining);
+ dest = input_buffer + remaining;
+ length = READ_BUFFER_SIZE - remaining;
+ } else {
+ remaining = 0;
+ length = READ_BUFFER_SIZE;
+ dest = input_buffer;
+ }
+
+ /* we've exhausted the read buffer, so give up!, these potential
+ * mp3 frames are way too big, and thus unlikely to be mp3 frames */
+ if (length == 0)
+ return false;
+
+ length = decoder_read(decoder, input_stream, dest, length);
+ if (length == 0)
+ return false;
+
+ mad_stream_buffer(&stream, input_buffer, length + remaining);
+ stream.error = MAD_ERROR_NONE;
+
+ return true;
+}
+
+#ifdef HAVE_ID3TAG
+static bool
+parse_id3_replay_gain_info(ReplayGainInfo &rgi,
+ struct id3_tag *tag)
+{
+ bool found = false;
+
+ rgi.Clear();
+
+ struct id3_frame *frame;
+ for (unsigned i = 0; (frame = id3_tag_findframe(tag, "TXXX", i)); i++) {
+ if (frame->nfields < 3)
+ continue;
+
+ char *const key = (char *)
+ id3_ucs4_latin1duplicate(id3_field_getstring
+ (&frame->fields[1]));
+ char *const value = (char *)
+ id3_ucs4_latin1duplicate(id3_field_getstring
+ (&frame->fields[2]));
+
+ if (ParseReplayGainTag(rgi, key, value))
+ found = true;
+
+ free(key);
+ free(value);
+ }
+
+ return found ||
+ /* fall back on RVA2 if no replaygain tags found */
+ tag_rva2_parse(tag, rgi);
+}
+#endif
+
+#ifdef HAVE_ID3TAG
+gcc_pure
+static MixRampInfo
+parse_id3_mixramp(struct id3_tag *tag)
+{
+ MixRampInfo result;
+
+ struct id3_frame *frame;
+ for (unsigned i = 0; (frame = id3_tag_findframe(tag, "TXXX", i)); i++) {
+ if (frame->nfields < 3)
+ continue;
+
+ char *const key = (char *)
+ id3_ucs4_latin1duplicate(id3_field_getstring
+ (&frame->fields[1]));
+ char *const value = (char *)
+ id3_ucs4_latin1duplicate(id3_field_getstring
+ (&frame->fields[2]));
+
+ ParseMixRampTag(result, key, value);
+
+ free(key);
+ free(value);
+ }
+
+ return result;
+}
+#endif
+
+inline void
+MadDecoder::ParseId3(size_t tagsize, Tag **mpd_tag)
+{
+#ifdef HAVE_ID3TAG
+ id3_byte_t *allocated = nullptr;
+
+ const id3_length_t count = stream.bufend - stream.this_frame;
+
+ const id3_byte_t *id3_data;
+ if (tagsize <= count) {
+ id3_data = stream.this_frame;
+ mad_stream_skip(&(stream), tagsize);
+ } else {
+ allocated = new id3_byte_t[tagsize];
+ memcpy(allocated, stream.this_frame, count);
+ mad_stream_skip(&(stream), count);
+
+ if (!decoder_read_full(decoder, input_stream,
+ allocated + count, tagsize - count)) {
+ LogDebug(mad_domain, "error parsing ID3 tag");
+ delete[] allocated;
+ return;
+ }
+
+ id3_data = allocated;
+ }
+
+ struct id3_tag *const id3_tag = id3_tag_parse(id3_data, tagsize);
+ if (id3_tag == nullptr) {
+ delete[] allocated;
+ return;
+ }
+
+ if (mpd_tag) {
+ Tag *tmp_tag = tag_id3_import(id3_tag);
+ if (tmp_tag != nullptr) {
+ delete *mpd_tag;
+ *mpd_tag = tmp_tag;
+ }
+ }
+
+ if (decoder != nullptr) {
+ ReplayGainInfo rgi;
+
+ if (parse_id3_replay_gain_info(rgi, id3_tag)) {
+ decoder_replay_gain(*decoder, &rgi);
+ found_replay_gain = true;
+ }
+
+ decoder_mixramp(*decoder, parse_id3_mixramp(id3_tag));
+ }
+
+ id3_tag_delete(id3_tag);
+
+ delete[] allocated;
+#else /* !HAVE_ID3TAG */
+ (void)mpd_tag;
+
+ /* This code is enabled when libid3tag is disabled. Instead
+ of parsing the ID3 frame, it just skips it. */
+
+ size_t count = stream.bufend - stream.this_frame;
+
+ if (tagsize <= count) {
+ mad_stream_skip(&stream, tagsize);
+ } else {
+ mad_stream_skip(&stream, count);
+ decoder_skip(decoder, input_stream, tagsize - count);
+ }
+#endif
+}
+
+#ifndef HAVE_ID3TAG
+/**
+ * This function emulates libid3tag when it is disabled. Instead of
+ * doing a real analyzation of the frame, it just checks whether the
+ * frame begins with the string "ID3". If so, it returns the length
+ * of the ID3 frame.
+ */
+static signed long
+id3_tag_query(const void *p0, size_t length)
+{
+ const char *p = (const char *)p0;
+
+ return length >= 10 && memcmp(p, "ID3", 3) == 0
+ ? (p[8] << 7) + p[9] + 10
+ : 0;
+}
+#endif /* !HAVE_ID3TAG */
+
+static enum mp3_action
+RecoverFrameError(struct mad_stream &stream)
+{
+ if (MAD_RECOVERABLE(stream.error))
+ return DECODE_SKIP;
+ else if (stream.error == MAD_ERROR_BUFLEN)
+ return DECODE_CONT;
+
+ FormatWarning(mad_domain,
+ "unrecoverable frame level error: %s",
+ mad_stream_errorstr(&stream));
+ return DECODE_BREAK;
+}
+
+enum mp3_action
+MadDecoder::DecodeNextFrameHeader(Tag **tag)
+{
+ if ((stream.buffer == nullptr || stream.error == MAD_ERROR_BUFLEN) &&
+ !FillBuffer())
+ return DECODE_BREAK;
+
+ if (mad_header_decode(&frame.header, &stream)) {
+ if (stream.error == MAD_ERROR_LOSTSYNC && stream.this_frame) {
+ signed long tagsize = id3_tag_query(stream.this_frame,
+ stream.bufend -
+ stream.this_frame);
+
+ if (tagsize > 0) {
+ if (tag && !(*tag)) {
+ ParseId3((size_t)tagsize, tag);
+ } else {
+ mad_stream_skip(&stream, tagsize);
+ }
+ return DECODE_CONT;
+ }
+ }
+
+ return RecoverFrameError(stream);
+ }
+
+ enum mad_layer new_layer = frame.header.layer;
+ if (layer == (mad_layer)0) {
+ if (new_layer != MAD_LAYER_II && new_layer != MAD_LAYER_III) {
+ /* Only layer 2 and 3 have been tested to work */
+ return DECODE_SKIP;
+ }
+
+ layer = new_layer;
+ } else if (new_layer != layer) {
+ /* Don't decode frames with a different layer than the first */
+ return DECODE_SKIP;
+ }
+
+ return DECODE_OK;
+}
+
+enum mp3_action
+MadDecoder::DecodeNextFrame()
+{
+ if ((stream.buffer == nullptr || stream.error == MAD_ERROR_BUFLEN) &&
+ !FillBuffer())
+ return DECODE_BREAK;
+
+ if (mad_frame_decode(&frame, &stream)) {
+ if (stream.error == MAD_ERROR_LOSTSYNC) {
+ signed long tagsize = id3_tag_query(stream.this_frame,
+ stream.bufend -
+ stream.this_frame);
+ if (tagsize > 0) {
+ mad_stream_skip(&stream, tagsize);
+ return DECODE_CONT;
+ }
+ }
+
+ return RecoverFrameError(stream);
+ }
+
+ return DECODE_OK;
+}
+
+/* xing stuff stolen from alsaplayer, and heavily modified by jat */
+static constexpr unsigned XI_MAGIC = (('X' << 8) | 'i');
+static constexpr unsigned NG_MAGIC = (('n' << 8) | 'g');
+static constexpr unsigned IN_MAGIC = (('I' << 8) | 'n');
+static constexpr unsigned FO_MAGIC = (('f' << 8) | 'o');
+
+enum xing_magic {
+ XING_MAGIC_XING, /* VBR */
+ XING_MAGIC_INFO /* CBR */
+};
+
+struct xing {
+ long flags; /* valid fields (see below) */
+ unsigned long frames; /* total number of frames */
+ unsigned long bytes; /* total number of bytes */
+ unsigned char toc[100]; /* 100-point seek table */
+ long scale; /* VBR quality */
+ enum xing_magic magic; /* header magic */
+};
+
+static const unsigned XING_FRAMES = 1;
+static const unsigned XING_BYTES = 2;
+static const unsigned XING_TOC = 4;
+static const unsigned XING_SCALE = 8;
+
+struct lame_version {
+ unsigned major;
+ unsigned minor;
+};
+
+struct lame {
+ char encoder[10]; /* 9 byte encoder name/version ("LAME3.97b") */
+ struct lame_version version; /* struct containing just the version */
+ float peak; /* replaygain peak */
+ float track_gain; /* replaygain track gain */
+ float album_gain; /* replaygain album gain */
+ int encoder_delay; /* # of added samples at start of mp3 */
+ int encoder_padding; /* # of added samples at end of mp3 */
+ int crc; /* CRC of the first 190 bytes of this frame */
+};
+
+static bool
+parse_xing(struct xing *xing, struct mad_bitptr *ptr, int *oldbitlen)
+{
+ int bitlen = *oldbitlen;
+
+ if (bitlen < 16)
+ return false;
+
+ const unsigned long bits = mad_bit_read(ptr, 16);
+ bitlen -= 16;
+
+ if (bits == XI_MAGIC) {
+ if (bitlen < 16)
+ return false;
+
+ if (mad_bit_read(ptr, 16) != NG_MAGIC)
+ return false;
+
+ bitlen -= 16;
+ xing->magic = XING_MAGIC_XING;
+ } else if (bits == IN_MAGIC) {
+ if (bitlen < 16)
+ return false;
+
+ if (mad_bit_read(ptr, 16) != FO_MAGIC)
+ return false;
+
+ bitlen -= 16;
+ xing->magic = XING_MAGIC_INFO;
+ }
+ else if (bits == NG_MAGIC) xing->magic = XING_MAGIC_XING;
+ else if (bits == FO_MAGIC) xing->magic = XING_MAGIC_INFO;
+ else
+ return false;
+
+ if (bitlen < 32)
+ return false;
+ xing->flags = mad_bit_read(ptr, 32);
+ bitlen -= 32;
+
+ if (xing->flags & XING_FRAMES) {
+ if (bitlen < 32)
+ return false;
+ xing->frames = mad_bit_read(ptr, 32);
+ bitlen -= 32;
+ }
+
+ if (xing->flags & XING_BYTES) {
+ if (bitlen < 32)
+ return false;
+ xing->bytes = mad_bit_read(ptr, 32);
+ bitlen -= 32;
+ }
+
+ if (xing->flags & XING_TOC) {
+ if (bitlen < 800)
+ return false;
+ for (unsigned i = 0; i < 100; ++i)
+ xing->toc[i] = mad_bit_read(ptr, 8);
+ bitlen -= 800;
+ }
+
+ if (xing->flags & XING_SCALE) {
+ if (bitlen < 32)
+ return false;
+ xing->scale = mad_bit_read(ptr, 32);
+ bitlen -= 32;
+ }
+
+ /* Make sure we consume no less than 120 bytes (960 bits) in hopes that
+ * the LAME tag is found there, and not right after the Xing header */
+ const int bitsleft = 960 - (*oldbitlen - bitlen);
+ if (bitsleft < 0)
+ return false;
+ else if (bitsleft > 0) {
+ mad_bit_read(ptr, bitsleft);
+ bitlen -= bitsleft;
+ }
+
+ *oldbitlen = bitlen;
+
+ return true;
+}
+
+static bool
+parse_lame(struct lame *lame, struct mad_bitptr *ptr, int *bitlen)
+{
+ /* Unlike the xing header, the lame tag has a fixed length. Fail if
+ * not all 36 bytes (288 bits) are there. */
+ if (*bitlen < 288)
+ return false;
+
+ for (unsigned i = 0; i < 9; i++)
+ lame->encoder[i] = (char)mad_bit_read(ptr, 8);
+ lame->encoder[9] = '\0';
+
+ *bitlen -= 72;
+
+ /* This is technically incorrect, since the encoder might not be lame.
+ * But there's no other way to determine if this is a lame tag, and we
+ * wouldn't want to go reading a tag that's not there. */
+ if (!StringStartsWith(lame->encoder, "LAME"))
+ return false;
+
+ if (sscanf(lame->encoder+4, "%u.%u",
+ &lame->version.major, &lame->version.minor) != 2)
+ return false;
+
+ FormatDebug(mad_domain, "detected LAME version %i.%i (\"%s\")",
+ lame->version.major, lame->version.minor, lame->encoder);
+
+ /* The reference volume was changed from the 83dB used in the
+ * ReplayGain spec to 89dB in lame 3.95.1. Bump the gain for older
+ * versions, since everyone else uses 89dB instead of 83dB.
+ * Unfortunately, lame didn't differentiate between 3.95 and 3.95.1, so
+ * it's impossible to make the proper adjustment for 3.95.
+ * Fortunately, 3.95 was only out for about a day before 3.95.1 was
+ * released. -- tmz */
+ int adj = 0;
+ if (lame->version.major < 3 ||
+ (lame->version.major == 3 && lame->version.minor < 95))
+ adj = 6;
+
+ mad_bit_read(ptr, 16);
+
+ lame->peak = mad_f_todouble(mad_bit_read(ptr, 32) << 5); /* peak */
+ FormatDebug(mad_domain, "LAME peak found: %f", lame->peak);
+
+ lame->track_gain = 0;
+ unsigned name = mad_bit_read(ptr, 3); /* gain name */
+ unsigned orig = mad_bit_read(ptr, 3); /* gain originator */
+ unsigned sign = mad_bit_read(ptr, 1); /* sign bit */
+ int gain = mad_bit_read(ptr, 9); /* gain*10 */
+ if (gain && name == 1 && orig != 0) {
+ lame->track_gain = ((sign ? -gain : gain) / 10.0) + adj;
+ FormatDebug(mad_domain, "LAME track gain found: %f",
+ lame->track_gain);
+ }
+
+ /* tmz reports that this isn't currently written by any version of lame
+ * (as of 3.97). Since we have no way of testing it, don't use it.
+ * Wouldn't want to go blowing someone's ears just because we read it
+ * wrong. :P -- jat */
+ lame->album_gain = 0;
+#if 0
+ name = mad_bit_read(ptr, 3); /* gain name */
+ orig = mad_bit_read(ptr, 3); /* gain originator */
+ sign = mad_bit_read(ptr, 1); /* sign bit */
+ gain = mad_bit_read(ptr, 9); /* gain*10 */
+ if (gain && name == 2 && orig != 0) {
+ lame->album_gain = ((sign ? -gain : gain) / 10.0) + adj;
+ FormatDebug(mad_domain, "LAME album gain found: %f",
+ lame->track_gain);
+ }
+#else
+ mad_bit_read(ptr, 16);
+#endif
+
+ mad_bit_read(ptr, 16);
+
+ lame->encoder_delay = mad_bit_read(ptr, 12);
+ lame->encoder_padding = mad_bit_read(ptr, 12);
+
+ FormatDebug(mad_domain, "encoder delay is %i, encoder padding is %i",
+ lame->encoder_delay, lame->encoder_padding);
+
+ mad_bit_read(ptr, 80);
+
+ lame->crc = mad_bit_read(ptr, 16);
+
+ *bitlen -= 216;
+
+ return true;
+}
+
+static inline SongTime
+mp3_frame_duration(const struct mad_frame *frame)
+{
+ return ToSongTime(frame->header.duration);
+}
+
+inline offset_type
+MadDecoder::ThisFrameOffset() const
+{
+ auto offset = input_stream.GetOffset();
+
+ if (stream.this_frame != nullptr)
+ offset -= stream.bufend - stream.this_frame;
+ else
+ offset -= stream.bufend - stream.buffer;
+
+ return offset;
+}
+
+inline offset_type
+MadDecoder::RestIncludingThisFrame() const
+{
+ return input_stream.GetSize() - ThisFrameOffset();
+}
+
+inline void
+MadDecoder::FileSizeToSongLength()
+{
+ if (input_stream.KnownSize()) {
+ offset_type rest = RestIncludingThisFrame();
+
+ const SongTime frame_duration = mp3_frame_duration(&frame);
+ const SongTime duration =
+ SongTime::FromScale<uint64_t>(rest,
+ frame.header.bitrate / 8);
+ total_time = duration;
+
+ max_frames = (frame_duration.IsPositive()
+ ? duration.count() / frame_duration.count()
+ : 0)
+ + FRAMES_CUSHION;
+ } else {
+ max_frames = FRAMES_CUSHION;
+ total_time = SignedSongTime::Negative();
+ }
+}
+
+inline bool
+MadDecoder::DecodeFirstFrame(Tag **tag)
+{
+ struct xing xing;
+ xing.frames = 0;
+
+ while (true) {
+ enum mp3_action ret;
+ do {
+ ret = DecodeNextFrameHeader(tag);
+ } while (ret == DECODE_CONT);
+ if (ret == DECODE_BREAK)
+ return false;
+ if (ret == DECODE_SKIP) continue;
+
+ do {
+ ret = DecodeNextFrame();
+ } while (ret == DECODE_CONT);
+ if (ret == DECODE_BREAK)
+ return false;
+ if (ret == DECODE_OK) break;
+ }
+
+ struct mad_bitptr ptr = stream.anc_ptr;
+ int bitlen = stream.anc_bitlen;
+
+ FileSizeToSongLength();
+
+ /*
+ * if an xing tag exists, use that!
+ */
+ if (parse_xing(&xing, &ptr, &bitlen)) {
+ mute_frame = MUTEFRAME_SKIP;
+
+ if ((xing.flags & XING_FRAMES) && xing.frames) {
+ mad_timer_t duration = frame.header.duration;
+ mad_timer_multiply(&duration, xing.frames);
+ total_time = ToSongTime(duration);
+ max_frames = xing.frames;
+ }
+
+ struct lame lame;
+ if (parse_lame(&lame, &ptr, &bitlen)) {
+ if (gapless_playback && input_stream.IsSeekable()) {
+ drop_start_samples = lame.encoder_delay +
+ DECODERDELAY;
+ drop_end_samples = lame.encoder_padding;
+ }
+
+ /* Album gain isn't currently used. See comment in
+ * parse_lame() for details. -- jat */
+ if (decoder != nullptr && !found_replay_gain &&
+ lame.track_gain) {
+ ReplayGainInfo rgi;
+ rgi.Clear();
+ rgi.tuples[REPLAY_GAIN_TRACK].gain = lame.track_gain;
+ rgi.tuples[REPLAY_GAIN_TRACK].peak = lame.peak;
+ decoder_replay_gain(*decoder, &rgi);
+ }
+ }
+ }
+
+ if (!max_frames)
+ return false;
+
+ if (max_frames > 8 * 1024 * 1024) {
+ FormatWarning(mad_domain,
+ "mp3 file header indicates too many frames: %lu",
+ max_frames);
+ return false;
+ }
+
+ frame_offsets = new long[max_frames];
+ times = new mad_timer_t[max_frames];
+
+ return true;
+}
+
+MadDecoder::~MadDecoder()
+{
+ mad_synth_finish(&synth);
+ mad_frame_finish(&frame);
+ mad_stream_finish(&stream);
+
+ delete[] frame_offsets;
+ delete[] times;
+}
+
+/* this is primarily used for getting total time for tags */
+static std::pair<bool, SignedSongTime>
+mad_decoder_total_file_time(InputStream &is)
+{
+ MadDecoder data(nullptr, is);
+ return data.DecodeFirstFrame(nullptr)
+ ? std::make_pair(true, data.total_time)
+ : std::make_pair(false, SignedSongTime::Negative());
+}
+
+long
+MadDecoder::TimeToFrame(SongTime t) const
+{
+ unsigned long i;
+
+ for (i = 0; i < highest_frame; ++i) {
+ auto frame_time = ToSongTime(times[i]);
+ if (frame_time >= t)
+ break;
+ }
+
+ return i;
+}
+
+void
+MadDecoder::UpdateTimerNextFrame()
+{
+ if (current_frame >= highest_frame) {
+ /* record this frame's properties in frame_offsets
+ (for seeking) and times */
+ bit_rate = frame.header.bitrate;
+
+ if (current_frame >= max_frames)
+ /* cap current_frame */
+ current_frame = max_frames - 1;
+ else
+ highest_frame++;
+
+ frame_offsets[current_frame] = ThisFrameOffset();
+
+ mad_timer_add(&timer, frame.header.duration);
+ times[current_frame] = timer;
+ } else
+ /* get the new timer value from "times" */
+ timer = times[current_frame];
+
+ current_frame++;
+ elapsed_time = ToSongTime(timer);
+}
+
+DecoderCommand
+MadDecoder::SendPCM(unsigned i, unsigned pcm_length)
+{
+ unsigned max_samples = sizeof(output_buffer) /
+ sizeof(output_buffer[0]) /
+ MAD_NCHANNELS(&frame.header);
+
+ while (i < pcm_length) {
+ unsigned int num_samples = pcm_length - i;
+ if (num_samples > max_samples)
+ num_samples = max_samples;
+
+ i += num_samples;
+
+ mad_fixed_to_24_buffer(output_buffer, &synth,
+ i - num_samples, i,
+ MAD_NCHANNELS(&frame.header));
+ num_samples *= MAD_NCHANNELS(&frame.header);
+
+ auto cmd = decoder_data(*decoder, input_stream, output_buffer,
+ sizeof(output_buffer[0]) * num_samples,
+ bit_rate / 1000);
+ if (cmd != DecoderCommand::NONE)
+ return cmd;
+ }
+
+ return DecoderCommand::NONE;
+}
+
+inline DecoderCommand
+MadDecoder::SyncAndSend()
+{
+ mad_synth_frame(&synth, &frame);
+
+ if (!found_first_frame) {
+ unsigned int samples_per_frame = synth.pcm.length;
+ drop_start_frames = drop_start_samples / samples_per_frame;
+ drop_end_frames = drop_end_samples / samples_per_frame;
+ drop_start_samples = drop_start_samples % samples_per_frame;
+ drop_end_samples = drop_end_samples % samples_per_frame;
+ found_first_frame = true;
+ }
+
+ if (drop_start_frames > 0) {
+ drop_start_frames--;
+ return DecoderCommand::NONE;
+ } else if ((drop_end_frames > 0) &&
+ (current_frame == (max_frames + 1 - drop_end_frames))) {
+ /* stop decoding, effectively dropping all remaining
+ frames */
+ return DecoderCommand::STOP;
+ }
+
+ unsigned i = 0;
+ if (!decoded_first_frame) {
+ i = drop_start_samples;
+ decoded_first_frame = true;
+ }
+
+ unsigned pcm_length = synth.pcm.length;
+ if (drop_end_samples &&
+ (current_frame == max_frames - drop_end_frames)) {
+ if (drop_end_samples >= pcm_length)
+ pcm_length = 0;
+ else
+ pcm_length -= drop_end_samples;
+ }
+
+ auto cmd = SendPCM(i, pcm_length);
+ if (cmd != DecoderCommand::NONE)
+ return cmd;
+
+ if (drop_end_samples &&
+ (current_frame == max_frames - drop_end_frames))
+ /* stop decoding, effectively dropping
+ * all remaining samples */
+ return DecoderCommand::STOP;
+
+ return DecoderCommand::NONE;
+}
+
+inline bool
+MadDecoder::Read()
+{
+ UpdateTimerNextFrame();
+
+ switch (mute_frame) {
+ DecoderCommand cmd;
+
+ case MUTEFRAME_SKIP:
+ mute_frame = MUTEFRAME_NONE;
+ break;
+ case MUTEFRAME_SEEK:
+ if (elapsed_time >= seek_time)
+ mute_frame = MUTEFRAME_NONE;
+ break;
+ case MUTEFRAME_NONE:
+ cmd = SyncAndSend();
+ if (cmd == DecoderCommand::SEEK) {
+ assert(input_stream.IsSeekable());
+
+ unsigned long j =
+ TimeToFrame(decoder_seek_time(*decoder));
+ if (j < highest_frame) {
+ if (Seek(frame_offsets[j])) {
+ current_frame = j;
+ decoder_command_finished(*decoder);
+ } else
+ decoder_seek_error(*decoder);
+ } else {
+ seek_time = decoder_seek_time(*decoder);
+ mute_frame = MUTEFRAME_SEEK;
+ decoder_command_finished(*decoder);
+ }
+ } else if (cmd != DecoderCommand::NONE)
+ return false;
+ }
+
+ while (true) {
+ enum mp3_action ret;
+ do {
+ Tag *tag = nullptr;
+
+ ret = DecodeNextFrameHeader(&tag);
+
+ if (tag != nullptr) {
+ decoder_tag(*decoder, input_stream,
+ std::move(*tag));
+ delete tag;
+ }
+ } while (ret == DECODE_CONT);
+ if (ret == DECODE_BREAK)
+ return false;
+
+ const bool skip = ret == DECODE_SKIP;
+
+ if (mute_frame == MUTEFRAME_NONE) {
+ do {
+ ret = DecodeNextFrame();
+ } while (ret == DECODE_CONT);
+ if (ret == DECODE_BREAK)
+ return false;
+ }
+
+ if (!skip && ret == DECODE_OK)
+ return true;
+ }
+}
+
+static void
+mp3_decode(Decoder &decoder, InputStream &input_stream)
+{
+ MadDecoder data(&decoder, input_stream);
+
+ Tag *tag = nullptr;
+ if (!data.DecodeFirstFrame(&tag)) {
+ delete tag;
+
+ if (decoder_get_command(decoder) == DecoderCommand::NONE)
+ LogError(mad_domain,
+ "input/Input does not appear to be a mp3 bit stream");
+ return;
+ }
+
+ Error error;
+ AudioFormat audio_format;
+ if (!audio_format_init_checked(audio_format,
+ data.frame.header.samplerate,
+ SampleFormat::S24_P32,
+ MAD_NCHANNELS(&data.frame.header),
+ error)) {
+ LogError(error);
+ delete tag;
+ return;
+ }
+
+ decoder_initialized(decoder, audio_format,
+ input_stream.IsSeekable(),
+ data.total_time);
+
+ if (tag != nullptr) {
+ decoder_tag(decoder, input_stream, std::move(*tag));
+ delete tag;
+ }
+
+ while (data.Read()) {}
+}
+
+static bool
+mad_decoder_scan_stream(InputStream &is,
+ const struct tag_handler *handler, void *handler_ctx)
+{
+ const auto result = mad_decoder_total_file_time(is);
+ if (!result.first)
+ return false;
+
+ if (!result.second.IsNegative())
+ tag_handler_invoke_duration(handler, handler_ctx,
+ SongTime(result.second));
+ return true;
+}
+
+static const char *const mp3_suffixes[] = { "mp3", "mp2", nullptr };
+static const char *const mp3_mime_types[] = { "audio/mpeg", nullptr };
+
+const struct DecoderPlugin mad_decoder_plugin = {
+ "mad",
+ mp3_plugin_init,
+ nullptr,
+ mp3_decode,
+ nullptr,
+ nullptr,
+ mad_decoder_scan_stream,
+ nullptr,
+ mp3_suffixes,
+ mp3_mime_types,
+};
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-23 00:40:06 +0000