MPD  0.20.18
MusicChunk.hxx
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1 /*
2  * Copyright 2003-2017 The Music Player Daemon Project
3  * http://www.musicpd.org
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
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18  */
19 
20 #ifndef MPD_MUSIC_CHUNK_HXX
21 #define MPD_MUSIC_CHUNK_HXX
22 
23 #include "Chrono.hxx"
24 #include "ReplayGainInfo.hxx"
25 #include "util/WritableBuffer.hxx"
26 
27 #ifndef NDEBUG
28 #include "AudioFormat.hxx"
29 #endif
30 
31 #include <stdint.h>
32 #include <stddef.h>
33 
34 static constexpr size_t CHUNK_SIZE = 4096;
35 
36 struct AudioFormat;
37 struct Tag;
38 
43 struct MusicChunk {
46 
51  MusicChunk *other = nullptr;
52 
57  float mix_ratio;
58 
60  uint16_t length = 0;
61 
63  uint16_t bit_rate;
64 
67 
74  Tag *tag = nullptr;
75 
81 
88  static constexpr unsigned IGNORE_REPLAY_GAIN = ~0u;
89 
96 
98  uint8_t data[CHUNK_SIZE];
99 
100 #ifndef NDEBUG
102 #endif
103 
104  MusicChunk() = default;
105 
106  MusicChunk(const MusicChunk &) = delete;
107 
108  ~MusicChunk();
109 
110  MusicChunk &operator=(const MusicChunk &) = delete;
111 
112  bool IsEmpty() const {
113  return length == 0 && tag == nullptr;
114  }
115 
116 #ifndef NDEBUG
117 
121  gcc_pure
122  bool CheckFormat(AudioFormat audio_format) const noexcept;
123 #endif
124 
137  SongTime data_time,
138  uint16_t bit_rate) noexcept;
139 
149  bool Expand(AudioFormat af, size_t length) noexcept;
150 };
151 
152 #endif
bool IsEmpty() const
Definition: MusicChunk.hxx:112
This structure describes the format of a raw PCM stream.
Definition: AudioFormat.hxx:37
The meta information about a song file.
Definition: Tag.hxx:34
A time stamp within a song.
Definition: Chrono.hxx:31
gcc_pure bool CheckFormat(AudioFormat audio_format) const noexcept
Checks if the audio format if the chunk is equal to the specified audio_format.
bool Expand(AudioFormat af, size_t length) noexcept
Increases the length of the chunk after the caller has written to the buffer returned by Write()...
Tag * tag
An optional tag associated with this chunk (and the following chunks); appears at song boundaries...
Definition: MusicChunk.hxx:74
float mix_ratio
The current mix ratio for cross-fading: 1.0 means play 100% of this chunk, 0.0 means play 100% of the...
Definition: MusicChunk.hxx:57
A chunk of music data.
Definition: MusicChunk.hxx:43
uint16_t length
number of bytes stored in this chunk
Definition: MusicChunk.hxx:60
MusicChunk * other
An optional chunk which should be mixed into this chunk.
Definition: MusicChunk.hxx:51
unsigned replay_gain_serial
A serial number for checking if replay gain info has changed since the last chunk.
Definition: MusicChunk.hxx:95
static constexpr size_t CHUNK_SIZE
Definition: MusicChunk.hxx:34
static constexpr unsigned IGNORE_REPLAY_GAIN
A magic value for replay_gain_serial which omits updating the #ReplayGainFilter.
Definition: MusicChunk.hxx:88
uint8_t data[CHUNK_SIZE]
the data (probably PCM)
Definition: MusicChunk.hxx:98
SignedSongTime time
the time stamp within the song
Definition: MusicChunk.hxx:66
ReplayGainInfo replay_gain_info
Replay gain information associated with this chunk.
Definition: MusicChunk.hxx:80
A variant of SongTime that is based on a signed integer.
Definition: Chrono.hxx:115
MusicChunk * next
the next chunk in a linked list
Definition: MusicChunk.hxx:45
MusicChunk & operator=(const MusicChunk &)=delete
uint16_t bit_rate
current bit rate of the source file
Definition: MusicChunk.hxx:63
#define gcc_pure
Definition: Compiler.h:116
MusicChunk()=default
WritableBuffer< void > Write(AudioFormat af, SongTime data_time, uint16_t bit_rate) noexcept
Prepares appending to the music chunk.
AudioFormat audio_format
Definition: MusicChunk.hxx:101