gstaudio

gstaudio — Support library for audio elements

Synopsis

#include <gst/audio/audio.h>

enum                GstAudioFlags;
enum                GstAudioFormat;
enum                GstAudioFormatFlags;
struct              GstAudioFormatInfo;
struct              GstAudioInfo;
enum                GstAudioLayout;
enum                GstAudioPackFlags;
void                (*GstAudioFormatPack)               (const GstAudioFormatInfo *info,
                                                         GstAudioPackFlags flags,
                                                         const gpointer src,
                                                         gpointer data,
                                                         gint length);
void                (*GstAudioFormatUnpack)             (const GstAudioFormatInfo *info,
                                                         GstAudioPackFlags flags,
                                                         gpointer dest,
                                                         const gpointer data,
                                                         gint length);
void                gst_audio_info_init                 (GstAudioInfo *info);
gboolean            gst_audio_info_from_caps            (GstAudioInfo *info,
                                                         const GstCaps *caps);
GstCaps *           gst_audio_info_to_caps              (const GstAudioInfo *info);
gboolean            gst_audio_info_convert              (const GstAudioInfo *info,
                                                         GstFormat src_fmt,
                                                         gint64 src_val,
                                                         GstFormat dest_fmt,
                                                         gint64 *dest_val);
const GstAudioFormatInfo * gst_audio_format_get_info    (GstAudioFormat format);
GstAudioInfo *      gst_audio_info_copy                 (const GstAudioInfo *info);
void                gst_audio_info_free                 (GstAudioInfo *info);
GstAudioInfo *      gst_audio_info_new                  (void);
void                gst_audio_info_set_format           (GstAudioInfo *info,
                                                         GstAudioFormat format,
                                                         gint rate,
                                                         gint channels,
                                                         const GstAudioChannelPosition *position);
GstAudioFormat      gst_audio_format_build_integer      (gboolean sign,
                                                         gint endianness,
                                                         gint width,
                                                         gint depth);
void                gst_audio_format_fill_silence       (const GstAudioFormatInfo *info,
                                                         gpointer dest,
                                                         gsize length);
GstAudioFormat      gst_audio_format_from_string        (const gchar *format);
const gchar *       gst_audio_format_to_string          (GstAudioFormat format);
#define             GST_AUDIO_FORMAT_INFO_DEPTH         (info)
#define             GST_AUDIO_FORMAT_INFO_ENDIANNESS    (info)
#define             GST_AUDIO_FORMAT_INFO_FLAGS         (info)
#define             GST_AUDIO_FORMAT_INFO_FORMAT        (info)
#define             GST_AUDIO_FORMAT_INFO_IS_FLOAT      (info)
#define             GST_AUDIO_FORMAT_INFO_IS_INTEGER    (info)
#define             GST_AUDIO_FORMAT_INFO_IS_BIG_ENDIAN (info)
#define             GST_AUDIO_FORMAT_INFO_IS_LITTLE_ENDIAN(info)
#define             GST_AUDIO_FORMAT_INFO_IS_SIGNED     (info)
#define             GST_AUDIO_FORMAT_INFO_NAME          (info)
#define             GST_AUDIO_FORMAT_INFO_WIDTH         (info)
#define             GST_AUDIO_INFO_BPF                  (info)
#define             GST_AUDIO_INFO_BPS                  (info)
#define             GST_AUDIO_INFO_CHANNELS             (info)
#define             GST_AUDIO_INFO_DEPTH                (i)
#define             GST_AUDIO_INFO_FLAGS                (info)
#define             GST_AUDIO_INFO_FORMAT               (i)
#define             GST_AUDIO_INFO_NAME                 (i)
#define             GST_AUDIO_INFO_POSITION             (info,
                                                         c)
#define             GST_AUDIO_INFO_RATE                 (info)
#define             GST_AUDIO_INFO_WIDTH                (i)
#define             GST_AUDIO_INFO_ENDIANNESS           (i)
#define             GST_AUDIO_INFO_IS_BIG_ENDIAN        (i)
#define             GST_AUDIO_INFO_IS_FLOAT             (i)
#define             GST_AUDIO_INFO_IS_INTEGER           (i)
#define             GST_AUDIO_INFO_IS_LITTLE_ENDIAN     (i)
#define             GST_AUDIO_INFO_IS_SIGNED            (i)
#define             GST_AUDIO_INFO_IS_UNPOSITIONED      (info)
#define             GST_AUDIO_INFO_IS_VALID             (i)
#define             GST_AUDIO_INFO_LAYOUT               (info)
#define             GST_FRAMES_TO_CLOCK_TIME            (frames,
                                                         rate)
#define             GST_CLOCK_TIME_TO_FRAMES            (clocktime,
                                                         rate)
#define             GST_AUDIO_DEF_RATE
GstBuffer *         gst_audio_buffer_clip               (GstBuffer *buffer,
                                                         GstSegment *segment,
                                                         gint rate,
                                                         gint bpf);

Description

This library contains some helper functions for audio elements.

Details

enum GstAudioFlags

typedef enum {
  GST_AUDIO_FLAG_NONE              = 0,
  GST_AUDIO_FLAG_UNPOSITIONED      = (1 << 0)
} GstAudioFlags;

Extra audio flags

GST_AUDIO_FLAG_NONE

no valid flag

GST_AUDIO_FLAG_UNPOSITIONED

the position array explicitly contains unpositioned channels.

enum GstAudioFormat

typedef enum {
  GST_AUDIO_FORMAT_UNKNOWN,
  GST_AUDIO_FORMAT_ENCODED,
  /* 8 bit */
  GST_AUDIO_FORMAT_S8,
  GST_AUDIO_FORMAT_U8,
  /* 16 bit */
  GST_AUDIO_FORMAT_S16LE,
  GST_AUDIO_FORMAT_S16BE,
  GST_AUDIO_FORMAT_U16LE,
  GST_AUDIO_FORMAT_U16BE,
  /* 24 bit in low 3 bytes of 32 bits*/
  GST_AUDIO_FORMAT_S24_32LE,
  GST_AUDIO_FORMAT_S24_32BE,
  GST_AUDIO_FORMAT_U24_32LE,
  GST_AUDIO_FORMAT_U24_32BE,
  /* 32 bit */
  GST_AUDIO_FORMAT_S32LE,
  GST_AUDIO_FORMAT_S32BE,
  GST_AUDIO_FORMAT_U32LE,
  GST_AUDIO_FORMAT_U32BE,
  /* 24 bit in 3 bytes*/
  GST_AUDIO_FORMAT_S24LE,
  GST_AUDIO_FORMAT_S24BE,
  GST_AUDIO_FORMAT_U24LE,
  GST_AUDIO_FORMAT_U24BE,
  /* 20 bit in 3 bytes*/
  GST_AUDIO_FORMAT_S20LE,
  GST_AUDIO_FORMAT_S20BE,
  GST_AUDIO_FORMAT_U20LE,
  GST_AUDIO_FORMAT_U20BE,
  /* 18 bit in 3 bytes*/
  GST_AUDIO_FORMAT_S18LE,
  GST_AUDIO_FORMAT_S18BE,
  GST_AUDIO_FORMAT_U18LE,
  GST_AUDIO_FORMAT_U18BE,
  /* float */
  GST_AUDIO_FORMAT_F32LE,
  GST_AUDIO_FORMAT_F32BE,
  GST_AUDIO_FORMAT_F64LE,
  GST_AUDIO_FORMAT_F64BE,
  /* native endianness equivalents */
  GST_AUDIO_FORMAT_S16 = _GST_AUDIO_FORMAT_NE(S16),
  GST_AUDIO_FORMAT_U16 = _GST_AUDIO_FORMAT_NE(U16),
  GST_AUDIO_FORMAT_S24_32 = _GST_AUDIO_FORMAT_NE(S24_32),
  GST_AUDIO_FORMAT_U24_32 = _GST_AUDIO_FORMAT_NE(U24_32),
  GST_AUDIO_FORMAT_S32 = _GST_AUDIO_FORMAT_NE(S32),
  GST_AUDIO_FORMAT_U32 = _GST_AUDIO_FORMAT_NE(U32),
  GST_AUDIO_FORMAT_S24 = _GST_AUDIO_FORMAT_NE(S24),
  GST_AUDIO_FORMAT_U24 = _GST_AUDIO_FORMAT_NE(U24),
  GST_AUDIO_FORMAT_S20 = _GST_AUDIO_FORMAT_NE(S20),
  GST_AUDIO_FORMAT_U20 = _GST_AUDIO_FORMAT_NE(U20),
  GST_AUDIO_FORMAT_S18 = _GST_AUDIO_FORMAT_NE(S18),
  GST_AUDIO_FORMAT_U18 = _GST_AUDIO_FORMAT_NE(U18),
  GST_AUDIO_FORMAT_F32 = _GST_AUDIO_FORMAT_NE(F32),
  GST_AUDIO_FORMAT_F64 = _GST_AUDIO_FORMAT_NE(F64)
} GstAudioFormat;

Enum value describing the most common audio formats.

GST_AUDIO_FORMAT_UNKNOWN

unknown or unset audio format

GST_AUDIO_FORMAT_ENCODED

encoded audio format

GST_AUDIO_FORMAT_S8

8 bits in 8 bits, signed

GST_AUDIO_FORMAT_U8

8 bits in 8 bits, unsigned

GST_AUDIO_FORMAT_S16LE

16 bits in 16 bits, signed, little endian

GST_AUDIO_FORMAT_S16BE

16 bits in 16 bits, signed, big endian

GST_AUDIO_FORMAT_U16LE

16 bits in 16 bits, unsigned, little endian

GST_AUDIO_FORMAT_U16BE

16 bits in 16 bits, unsigned, big endian

GST_AUDIO_FORMAT_S24_32LE

24 bits in 32 bits, signed, little endian

GST_AUDIO_FORMAT_S24_32BE

24 bits in 32 bits, signed, big endian

GST_AUDIO_FORMAT_U24_32LE

24 bits in 32 bits, unsigned, little endian

GST_AUDIO_FORMAT_U24_32BE

24 bits in 32 bits, unsigned, big endian

GST_AUDIO_FORMAT_S32LE

32 bits in 32 bits, signed, little endian

GST_AUDIO_FORMAT_S32BE

32 bits in 32 bits, signed, big endian

GST_AUDIO_FORMAT_U32LE

32 bits in 32 bits, unsigned, little endian

GST_AUDIO_FORMAT_U32BE

32 bits in 32 bits, unsigned, big endian

GST_AUDIO_FORMAT_S24LE

24 bits in 24 bits, signed, little endian

GST_AUDIO_FORMAT_S24BE

24 bits in 24 bits, signed, big endian

GST_AUDIO_FORMAT_U24LE

24 bits in 24 bits, unsigned, little endian

GST_AUDIO_FORMAT_U24BE

24 bits in 24 bits, unsigned, big endian

GST_AUDIO_FORMAT_S20LE

20 bits in 24 bits, signed, little endian

GST_AUDIO_FORMAT_S20BE

20 bits in 24 bits, signed, big endian

GST_AUDIO_FORMAT_U20LE

20 bits in 24 bits, unsigned, little endian

GST_AUDIO_FORMAT_U20BE

20 bits in 24 bits, unsigned, big endian

GST_AUDIO_FORMAT_S18LE

18 bits in 24 bits, signed, little endian

GST_AUDIO_FORMAT_S18BE

18 bits in 24 bits, signed, big endian

GST_AUDIO_FORMAT_U18LE

18 bits in 24 bits, unsigned, little endian

GST_AUDIO_FORMAT_U18BE

18 bits in 24 bits, unsigned, big endian

GST_AUDIO_FORMAT_F32LE

32-bit floating point samples, little endian

GST_AUDIO_FORMAT_F32BE

32-bit floating point samples, big endian

GST_AUDIO_FORMAT_F64LE

64-bit floating point samples, little endian

GST_AUDIO_FORMAT_F64BE

64-bit floating point samples, big endian

GST_AUDIO_FORMAT_S16

16 bits in 16 bits, signed, native endianness

GST_AUDIO_FORMAT_U16

16 bits in 16 bits, unsigned, native endianness

GST_AUDIO_FORMAT_S24_32

24 bits in 32 bits, signed, native endianness

GST_AUDIO_FORMAT_U24_32

24 bits in 32 bits, unsigned, native endianness

GST_AUDIO_FORMAT_S32

32 bits in 32 bits, signed, native endianness

GST_AUDIO_FORMAT_U32

32 bits in 32 bits, unsigned, native endianness

GST_AUDIO_FORMAT_S24

24 bits in 24 bits, signed, native endianness

GST_AUDIO_FORMAT_U24

24 bits in 24 bits, unsigned, native endianness

GST_AUDIO_FORMAT_S20

20 bits in 24 bits, signed, native endianness

GST_AUDIO_FORMAT_U20

20 bits in 24 bits, unsigned, native endianness

GST_AUDIO_FORMAT_S18

18 bits in 24 bits, signed, native endianness

GST_AUDIO_FORMAT_U18

18 bits in 24 bits, unsigned, native endianness

GST_AUDIO_FORMAT_F32

32-bit floating point samples, native endianness

GST_AUDIO_FORMAT_F64

64-bit floating point samples, native endianness

enum GstAudioFormatFlags

typedef enum {
  GST_AUDIO_FORMAT_FLAG_INTEGER  = (1 << 0),
  GST_AUDIO_FORMAT_FLAG_FLOAT    = (1 << 1),
  GST_AUDIO_FORMAT_FLAG_SIGNED   = (1 << 2),
  GST_AUDIO_FORMAT_FLAG_COMPLEX  = (1 << 4),
  GST_AUDIO_FORMAT_FLAG_UNPACK   = (1 << 5)
} GstAudioFormatFlags;

The different audio flags that a format info can have.

GST_AUDIO_FORMAT_FLAG_INTEGER

integer samples

GST_AUDIO_FORMAT_FLAG_FLOAT

float samples

GST_AUDIO_FORMAT_FLAG_SIGNED

signed samples

GST_AUDIO_FORMAT_FLAG_COMPLEX

complex layout

GST_AUDIO_FORMAT_FLAG_UNPACK

the format can be used in GstAudioFormatUnpack and GstAudioFormatPack functions

struct GstAudioFormatInfo

struct GstAudioFormatInfo {
  GstAudioFormat format;
  const gchar *name;
  const gchar *description;
  GstAudioFormatFlags flags;
  gint endianness;
  gint width;
  gint depth;
  guint8 silence[8];

  GstAudioFormat unpack_format;
  GstAudioFormatUnpack unpack_func;
  GstAudioFormatPack pack_func;
};

Information for an audio format.

GstAudioFormat format;

GstAudioFormat

const gchar *name;

string representation of the format

const gchar *description;

user readable description of the format

GstAudioFormatFlags flags;

GstAudioFormatFlags

gint endianness;

the endianness

gint width;

amount of bits used for one sample

gint depth;

amount of valid bits in width

guint8 silence[8];

width/8 bytes with 1 silent sample

GstAudioFormat unpack_format;

the format of the unpacked samples

GstAudioFormatUnpack unpack_func;

function to unpack samples

GstAudioFormatPack pack_func;

function to pack samples

struct GstAudioInfo

struct GstAudioInfo {
  const GstAudioFormatInfo *finfo;
  GstAudioFlags             flags;
  GstAudioLayout            layout;
  gint                      rate;
  gint                      channels;
  gint                      bpf;
  GstAudioChannelPosition   position[64];
};

Information describing audio properties. This information can be filled in from GstCaps with gst_audio_info_from_caps().

Use the provided macros to access the info in this structure.

const GstAudioFormatInfo *finfo;

the format info of the audio

GstAudioFlags flags;

additional audio flags

GstAudioLayout layout;

audio layout

gint rate;

the audio sample rate

gint channels;

the number of channels

gint bpf;

the number of bytes for one frame, this is the size of one sample * channels

GstAudioChannelPosition position[64];

the positions for each channel

enum GstAudioLayout

typedef enum {
  GST_AUDIO_LAYOUT_INTERLEAVED = 0,
  GST_AUDIO_LAYOUT_NON_INTERLEAVED
} GstAudioLayout;

Layout of the audio samples for the different channels.

GST_AUDIO_LAYOUT_INTERLEAVED

interleaved audio

GST_AUDIO_LAYOUT_NON_INTERLEAVED

non-interleaved audio

enum GstAudioPackFlags

typedef enum {
  GST_AUDIO_PACK_FLAG_NONE       = 0
} GstAudioPackFlags;

The different flags that can be used when packing and unpacking.

GST_AUDIO_PACK_FLAG_NONE

No flag

GstAudioFormatPack ()

void                (*GstAudioFormatPack)               (const GstAudioFormatInfo *info,
                                                         GstAudioPackFlags flags,
                                                         const gpointer src,
                                                         gpointer data,
                                                         gint length);

Packs length samples from src to the data array in format info. The samples from source have each channel interleaved and will be packed into data.

info :

a GstAudioFormatInfo

src :

a source array. [array][element-type guint8]

data :

pointer to the destination data. [array][element-type guint8]

length :

the amount of samples to pack.

GstAudioFormatUnpack ()

void                (*GstAudioFormatUnpack)             (const GstAudioFormatInfo *info,
                                                         GstAudioPackFlags flags,
                                                         gpointer dest,
                                                         const gpointer data,
                                                         gint length);

Unpacks length samples from the given data of format info. The samples will be unpacked into dest which each channel interleaved. dest should at least be big enough to hold length * channels * size(unpack_format) bytes.

info :

a GstAudioFormatInfo

dest :

a destination array. [array][element-type guint8]

data :

pointer to the audio data. [array][element-type guint8]

length :

the amount of samples to unpack.

gst_audio_info_init ()

void                gst_audio_info_init                 (GstAudioInfo *info);

Initialize info with default values.

info :

a GstAudioInfo

gst_audio_info_from_caps ()

gboolean            gst_audio_info_from_caps            (GstAudioInfo *info,
                                                         const GstCaps *caps);

Parse caps and update info.

info :

a GstAudioInfo

caps :

a GstCaps

Returns :

TRUE if caps could be parsed

gst_audio_info_to_caps ()

GstCaps *           gst_audio_info_to_caps              (const GstAudioInfo *info);

Convert the values of info into a GstCaps.

info :

a GstAudioInfo

Returns :

the new GstCaps containing the info of info. [transfer full]

gst_audio_info_convert ()

gboolean            gst_audio_info_convert              (const GstAudioInfo *info,
                                                         GstFormat src_fmt,
                                                         gint64 src_val,
                                                         GstFormat dest_fmt,
                                                         gint64 *dest_val);

Converts among various GstFormat types. This function handles GST_FORMAT_BYTES, GST_FORMAT_TIME, and GST_FORMAT_DEFAULT. For raw audio, GST_FORMAT_DEFAULT corresponds to audio frames. This function can be used to handle pad queries of the type GST_QUERY_CONVERT.

info :

a GstAudioInfo

src_fmt :

GstFormat of the src_val

src_val :

value to convert

dest_fmt :

GstFormat of the dest_val

dest_val :

pointer to destination value

Returns :

TRUE if the conversion was successful.

gst_audio_format_get_info ()

const GstAudioFormatInfo * gst_audio_format_get_info    (GstAudioFormat format);

Get the GstAudioFormatInfo for format

format :

a GstAudioFormat

Returns :

The GstAudioFormatInfo for format.

gst_audio_info_copy ()

GstAudioInfo *      gst_audio_info_copy                 (const GstAudioInfo *info);

Copy a GstAudioInfo structure.

info :

a GstAudioInfo

Returns :

a new GstAudioInfo. free with gst_audio_info_free.

gst_audio_info_free ()

void                gst_audio_info_free                 (GstAudioInfo *info);

Free a GstAudioInfo structure previously allocated with gst_audio_info_new() or gst_audio_info_copy().

info :

a GstAudioInfo

gst_audio_info_new ()

GstAudioInfo *      gst_audio_info_new                  (void);

Allocate a new GstAudioInfo that is also initialized with gst_audio_info_init().

Returns :

a new GstAudioInfo. free with gst_audio_info_free().

gst_audio_info_set_format ()

void                gst_audio_info_set_format           (GstAudioInfo *info,
                                                         GstAudioFormat format,
                                                         gint rate,
                                                         gint channels,
                                                         const GstAudioChannelPosition *position);

Set the default info for the audio info of format and rate and channels.

info :

a GstAudioInfo

format :

the format

rate :

the samplerate

channels :

the number of channels

position :

the channel positions

gst_audio_format_build_integer ()

GstAudioFormat      gst_audio_format_build_integer      (gboolean sign,
                                                         gint endianness,
                                                         gint width,
                                                         gint depth);

Construct a GstAudioFormat with given parameters.

sign :

signed or unsigned format

endianness :

G_LITTLE_ENDIAN or G_BIG_ENDIAN

width :

amount of bits used per sample

depth :

amount of used bits in width

Returns :

a GstAudioFormat or GST_AUDIO_FORMAT_UNKNOWN when no audio format exists with the given parameters.

gst_audio_format_fill_silence ()

void                gst_audio_format_fill_silence       (const GstAudioFormatInfo *info,
                                                         gpointer dest,
                                                         gsize length);

Fill length bytes in dest with silence samples for info.

info :

a GstAudioFormatInfo

dest :

a destination to fill. [array length=length][element-type guint8]

length :

the length to fill

gst_audio_format_from_string ()

GstAudioFormat      gst_audio_format_from_string        (const gchar *format);

Convert the format string to its GstAudioFormat.

format :

a format string

Returns :

the GstAudioFormat for format or GST_AUDIO_FORMAT_UNKNOWN when the string is not a known format.

gst_audio_format_to_string ()

const gchar *       gst_audio_format_to_string          (GstAudioFormat format);

GST_AUDIO_FORMAT_INFO_DEPTH()

#define GST_AUDIO_FORMAT_INFO_DEPTH(info)            ((info)->depth)

GST_AUDIO_FORMAT_INFO_ENDIANNESS()

#define GST_AUDIO_FORMAT_INFO_ENDIANNESS(info)       ((info)->endianness)

GST_AUDIO_FORMAT_INFO_FLAGS()

#define GST_AUDIO_FORMAT_INFO_FLAGS(info)            ((info)->flags)

GST_AUDIO_FORMAT_INFO_FORMAT()

#define GST_AUDIO_FORMAT_INFO_FORMAT(info)           ((info)->format)

GST_AUDIO_FORMAT_INFO_IS_FLOAT()

#define GST_AUDIO_FORMAT_INFO_IS_FLOAT(info)         !!((info)->flags & GST_AUDIO_FORMAT_FLAG_FLOAT)

GST_AUDIO_FORMAT_INFO_IS_INTEGER()

#define GST_AUDIO_FORMAT_INFO_IS_INTEGER(info)       !!((info)->flags & GST_AUDIO_FORMAT_FLAG_INTEGER)

GST_AUDIO_FORMAT_INFO_IS_BIG_ENDIAN()

#define GST_AUDIO_FORMAT_INFO_IS_BIG_ENDIAN(info)    ((info)->endianness == G_BIG_ENDIAN)

GST_AUDIO_FORMAT_INFO_IS_LITTLE_ENDIAN()

#define GST_AUDIO_FORMAT_INFO_IS_LITTLE_ENDIAN(info) ((info)->endianness == G_LITTLE_ENDIAN)

GST_AUDIO_FORMAT_INFO_IS_SIGNED()

#define GST_AUDIO_FORMAT_INFO_IS_SIGNED(info)        !!((info)->flags & GST_AUDIO_FORMAT_FLAG_SIGNED)

GST_AUDIO_FORMAT_INFO_NAME()

#define GST_AUDIO_FORMAT_INFO_NAME(info)             ((info)->name)

GST_AUDIO_FORMAT_INFO_WIDTH()

#define GST_AUDIO_FORMAT_INFO_WIDTH(info)            ((info)->width)

GST_AUDIO_INFO_BPF()

#define GST_AUDIO_INFO_BPF(info)             ((info)->bpf)

GST_AUDIO_INFO_BPS()

#define GST_AUDIO_INFO_BPS(info)             (GST_AUDIO_INFO_DEPTH(info) >> 3)

GST_AUDIO_INFO_CHANNELS()

#define GST_AUDIO_INFO_CHANNELS(info)        ((info)->channels)

GST_AUDIO_INFO_DEPTH()

#define GST_AUDIO_INFO_DEPTH(i)              (GST_AUDIO_FORMAT_INFO_DEPTH((i)->finfo))

GST_AUDIO_INFO_FLAGS()

#define GST_AUDIO_INFO_FLAGS(info)           ((info)->flags)

GST_AUDIO_INFO_FORMAT()

#define GST_AUDIO_INFO_FORMAT(i)             (GST_AUDIO_FORMAT_INFO_FORMAT((i)->finfo))

GST_AUDIO_INFO_NAME()

#define GST_AUDIO_INFO_NAME(i)               (GST_AUDIO_FORMAT_INFO_NAME((i)->finfo))

GST_AUDIO_INFO_POSITION()

#define GST_AUDIO_INFO_POSITION(info,c)      ((info)->position[c])

GST_AUDIO_INFO_RATE()

#define GST_AUDIO_INFO_RATE(info)            ((info)->rate)

GST_AUDIO_INFO_WIDTH()

#define GST_AUDIO_INFO_WIDTH(i)              (GST_AUDIO_FORMAT_INFO_WIDTH((i)->finfo))

GST_AUDIO_INFO_ENDIANNESS()

#define GST_AUDIO_INFO_ENDIANNESS(i)         (GST_AUDIO_FORMAT_INFO_ENDIANNESS((i)->finfo))

GST_AUDIO_INFO_IS_BIG_ENDIAN()

#define GST_AUDIO_INFO_IS_BIG_ENDIAN(i)      (GST_AUDIO_FORMAT_INFO_IS_BIG_ENDIAN((i)->finfo))

GST_AUDIO_INFO_IS_FLOAT()

#define GST_AUDIO_INFO_IS_FLOAT(i)           (GST_AUDIO_FORMAT_INFO_IS_FLOAT((i)->finfo))

GST_AUDIO_INFO_IS_INTEGER()

#define GST_AUDIO_INFO_IS_INTEGER(i)         (GST_AUDIO_FORMAT_INFO_IS_INTEGER((i)->finfo))

GST_AUDIO_INFO_IS_LITTLE_ENDIAN()

#define GST_AUDIO_INFO_IS_LITTLE_ENDIAN(i)   (GST_AUDIO_FORMAT_INFO_IS_LITTLE_ENDIAN((i)->finfo))

GST_AUDIO_INFO_IS_SIGNED()

#define GST_AUDIO_INFO_IS_SIGNED(i)          (GST_AUDIO_FORMAT_INFO_IS_SIGNED((i)->finfo))

GST_AUDIO_INFO_IS_UNPOSITIONED()

#define GST_AUDIO_INFO_IS_UNPOSITIONED(info) ((info)->flags & GST_AUDIO_FLAG_UNPOSITIONED)

GST_AUDIO_INFO_IS_VALID()

#define GST_AUDIO_INFO_IS_VALID(i)           ((i)->finfo != NULL && (i)->rate > 0 && (i)->channels > 0 && (i)->bpf > 0)

GST_AUDIO_INFO_LAYOUT()

#define GST_AUDIO_INFO_LAYOUT(info)          ((info)->layout)

GST_FRAMES_TO_CLOCK_TIME()

#define             GST_FRAMES_TO_CLOCK_TIME(frames, rate)

Calculate clocktime from sample frames and rate.

frames :

sample frames

rate :

sampling rate

GST_CLOCK_TIME_TO_FRAMES()

#define             GST_CLOCK_TIME_TO_FRAMES(clocktime, rate)

Calculate frames from clocktime and sample rate.

clocktime :

clock time

rate :

sampling rate

GST_AUDIO_DEF_RATE

#define GST_AUDIO_DEF_RATE 44100

Standard sampling rate used in consumer audio.


gst_audio_buffer_clip ()

GstBuffer *         gst_audio_buffer_clip               (GstBuffer *buffer,
                                                         GstSegment *segment,
                                                         gint rate,
                                                         gint bpf);

Clip the buffer to the given GstSegment.

After calling this function the caller does not own a reference to buffer anymore.

buffer :

The buffer to clip. [transfer full]

segment :

Segment in GST_FORMAT_TIME or GST_FORMAT_DEFAULT to which the buffer should be clipped.

rate :

sample rate.

bpf :

size of one audio frame in bytes. This is the size of one sample * channels.

Returns :

NULL if the buffer is completely outside the configured segment, otherwise the clipped buffer is returned. If the buffer has no timestamp, it is assumed to be inside the segment and is not clipped. [transfer full]