ccAudio
ost::AudioResample Class Reference

The AudioResample class is used to manage linear intropolation buffering for rate conversions. More...

#include <audio2.h>

Inheritance diagram for ost::AudioResample:
ost::Audio

Public Member Functions

 AudioResample (Rate mul, Rate div)
 
 ~AudioResample ()
 
size_t process (Linear from, Linear to, size_t count)
 
size_t estimate (size_t count)
 

Protected Attributes

unsigned mfact
 
unsigned dfact
 
unsigned max
 
unsigned gpos
 
unsigned ppos
 
Sample last
 
Linear buffer
 

Additional Inherited Members

- Public Types inherited from ost::Audio
enum  Rate {
  rateUnknown , rate6khz = 6000 , rate8khz = 8000 , rate16khz = 16000 ,
  rate32khz = 32000 , rate44khz = 44100
}
 Audio encoding rate, samples per second. More...
 
enum  Mode {
  modeRead , modeReadAny , modeReadOne , modeWrite ,
  modeCache , modeInfo , modeFeed , modeAppend ,
  modeCreate
}
 File processing mode, whether to skip missing files, etc. More...
 
enum  Encoding {
  unknownEncoding = 0 , g721ADPCM , g722Audio , g722_7bit ,
  g722_6bit , g723_2bit , g723_3bit , g723_5bit ,
  gsmVoice , msgsmVoice , mulawAudio , alawAudio ,
  mp1Audio , mp2Audio , mp3Audio , okiADPCM ,
  voxADPCM , sx73Voice , sx96Voice , cdaStereo ,
  cdaMono , pcm8Stereo , pcm8Mono , pcm16Stereo ,
  pcm16Mono , pcm32Stereo , pcm32Mono , speexVoice ,
  speexAudio , g729Audio , ilbcAudio , speexUltra ,
  speexNarrow = speexVoice , speexWide = speexAudio , g723_4bit = g721ADPCM
}
 Audio encoding formats. More...
 
enum  Format {
  raw , snd , riff , mpeg ,
  wave
}
 Audio container file format. More...
 
enum  DeviceMode { PLAY , RECORD , PLAYREC }
 Audio device access mode. More...
 
enum  Error {
  errSuccess = 0 , errReadLast , errNotOpened , errEndOfFile ,
  errStartOfFile , errRateInvalid , errEncodingInvalid , errReadInterrupt ,
  errWriteInterrupt , errReadFailure , errWriteFailure , errReadIncomplete ,
  errWriteIncomplete , errRequestInvalid , errTOCFailed , errStatFailed ,
  errInvalidTrack , errPlaybackFailed , errNotPlaying , errNoCodec
}
 Audio error conditions. More...
 
typedef int16_t snd16_t
 
typedef int32_t snd32_t
 
typedef int16_t Level
 
typedef int16_t Sample
 
typedef int16_t * Linear
 
typedef unsigned long timeout_t
 
typedef unsigned char * Encoded
 
typedef enum Rate Rate
 
typedef enum Mode Mode
 
typedef enum Encoding Encoding
 
typedef enum Format Format
 
typedef enum DeviceMode DeviceMode
 
typedef enum Error Error
 
- Static Public Member Functions inherited from ost::Audio
static Level tolevel (float dbm)
 Convert dbm power level to integer value (0-32768).
 
static float todbm (Level power)
 Convert integer power levels to dbm.
 
static bool hasDevice (unsigned device=0)
 Test for the presense of a specified (indexed) audio device.
 
static AudioDevicegetDevice (unsigned device=0, DeviceMode mode=PLAY)
 Get a audio device object that can be used to play or record audio.
 
static const char * getCodecPath (void)
 Get pathname to where loadable codec modules are stored.
 
static const char * getMIME (Info &info)
 Get the mime descriptive type for a given Audio encoding description, usually retrieved from a newly opened audio file.
 
static const char * getName (Encoding encoding)
 Get the short ascii description used for the given audio encoding type.
 
static const char * getExtension (Encoding encoding)
 Get the preferred file extension name to use for a given audio encoding type.
 
static Encoding getEncoding (const char *name)
 Get the audio encoding format that is specified by a short ascii name.
 
static Encoding getStereo (Encoding encoding)
 Get the stereo encoding format associated with the given format.
 
static Encoding getMono (Encoding encoding)
 Get the mono encoding format associated with the given format.
 
static bool isLinear (Encoding encoding)
 Test if the audio encoding format is a linear one.
 
static bool isBuffered (Encoding encoding)
 Test if the audio encoding format must be packetized (that is, has irregular sized frames) and must be processed only through buffered codecs.
 
static bool isMono (Encoding encoding)
 Test if the audio encoding format is a mono format.
 
static bool isStereo (Encoding encoding)
 Test if the audio encoding format is a stereo format.
 
static Rate getRate (Encoding encoding)
 Return default sample rate associated with the specified audio encoding format.
 
static Rate getRate (Encoding e, Rate request)
 Return optional rate setting effect.
 
static timeout_t getFraming (Encoding encoding, timeout_t timeout=0)
 Return frame timing for an audio encoding format.
 
static timeout_t getFraming (Info &info, timeout_t timeout=0)
 Return frame time for an audio source description.
 
static bool isEndian (Encoding encoding)
 Test if the endian byte order of the encoding format is different from the machine's native byte order.
 
static bool isEndian (Info &info)
 Test if the endian byte order of the audio source description is different from the machine's native byte order.
 
static bool swapEndian (Encoding encoding, void *buffer, unsigned number)
 Optionally swap endian of audio data if the encoding format endian byte order is different from the machine's native endian.
 
static void swapEncoded (Info &info, Encoded data, size_t bytes)
 Optionally swap endian of encoded audio data based on the audio encoding type, and relationship to native byte order.
 
static bool swapEndian (Info &info, void *buffer, unsigned number)
 Optionally swap endian of audio data if the audio source description byte order is different from the machine's native endian byte order.
 
static Level getImpulse (Encoding encoding, void *buffer, unsigned number)
 Get the energey impulse level of a frame of audio data.
 
static Level getImpulse (Info &info, void *buffer, unsigned number=0)
 Get the energey impulse level of a frame of audio data.
 
static Level getPeak (Encoding encoding, void *buffer, unsigned number)
 Get the peak (highest energy) level found in a frame of audio data.
 
static Level getPeak (Info &info, void *buffer, unsigned number=0)
 Get the peak (highest energy) level found in a frame of audio data.
 
static void toTimestamp (timeout_t duration, char *address, size_t size)
 Provide ascii timestamp representation of a timeout value.
 
static timeout_t toTimeout (const char *timestamp)
 Convert ascii timestamp representation to a timeout number.
 
static int getFrame (Encoding encoding, int samples=0)
 Returns the number of bytes in a sample frame for the given encoding type, rounded up to the nearest integer.
 
static int getCount (Encoding encoding)
 Returns the number of samples in all channels for a frame in the given encoding.
 
static unsigned long toSamples (Encoding encoding, size_t bytes)
 Compute byte counts of audio data into number of samples based on the audio encoding format used.
 
static unsigned long toSamples (Info &info, size_t bytes)
 Compute byte counts of audio data into number of samples based on the audio source description used.
 
static size_t toBytes (Info &info, unsigned long number)
 Compute the number of bytes a given number of samples in a given audio encoding will occupy.
 
static size_t toBytes (Encoding encoding, unsigned long number)
 Compute the number of bytes a given number of samples in a given audio encoding will occupy.
 
static void fill (unsigned char *address, int number, Encoding encoding)
 Fill an audio buffer with "empty" (silent) audio data, based on the audio encoding format.
 
static bool loadPlugin (const char *path)
 Load a dso plugin (codec plugin), used internally...
 
static size_t maxFramesize (Info &info)
 Maximum framesize for a given coding that may be needed to store a result.
 
- Static Public Attributes inherited from ost::Audio
static const unsigned ndata
 

Detailed Description

The AudioResample class is used to manage linear intropolation buffering for rate conversions.

Author
David Sugar dyfet.nosp@m.@ost.nosp@m.el.co.nosp@m.m

linear intropolation and rate conversion.

Constructor & Destructor Documentation

◆ AudioResample()

ost::AudioResample::AudioResample ( Rate mul,
Rate div )

◆ ~AudioResample()

ost::AudioResample::~AudioResample ( )

Member Function Documentation

◆ estimate()

size_t ost::AudioResample::estimate ( size_t count)

◆ process()

size_t ost::AudioResample::process ( Linear from,
Linear to,
size_t count )

Member Data Documentation

◆ buffer

Linear ost::AudioResample::buffer
protected

◆ dfact

unsigned ost::AudioResample::dfact
protected

◆ gpos

unsigned ost::AudioResample::gpos
protected

◆ last

Sample ost::AudioResample::last
protected

◆ max

unsigned ost::AudioResample::max
protected

◆ mfact

unsigned ost::AudioResample::mfact
protected

◆ ppos

unsigned ost::AudioResample::ppos
protected

The documentation for this class was generated from the following file: