Differences between revisions 1 and 2

SDL_AudioFormat

A typedef that contains audio format data and flags.

Contents

SDL_AudioFormat

Values

Bit Meanings

These are what the 16 bits in SDL_AudioFormat currently mean:

++-----------------------sample is signed if set
||
||       ++-----------sample is bigendian if set
||       ||
||       ||          ++---sample is float if set
||       ||          ||
||       ||          || +---sample bit size---+
||       ||          || |                     |
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

OR it could look like this

Bit	Meaning
15	sample is signed if set
12	sample is bigendian if set
08	sample is float if set
07-00	sample bit size

Unspecified bits are always zero. There are macros in SDL 1.3 and later to query these bits.

Audio flags

SDL_AUDIO_MASK_BITSIZE	(0xFF)
SDL_AUDIO_MASK_DATATYPE	(1<<8)
SDL_AUDIO_MASK_ENDIAN	(1<<12)
SDL_AUDIO_MASK_SIGNED	(1<<15)
SDL_AUDIO_BITSIZE(x)	(x & SDL_AUDIO_MASK_BITSIZE)
SDL_AUDIO_ISFLOAT(x)	(x & SDL_AUDIO_MASK_DATATYPE)
SDL_AUDIO_ISBIGENDIAN(x)	(x & SDL_AUDIO_MASK_ENDIAN)
SDL_AUDIO_ISSIGNED(x)	(x & SDL_AUDIO_MASK_SIGNED)
SDL_AUDIO_ISINT(x)	(!SDL_AUDIO_ISFLOAT(x))
SDL_AUDIO_ISLITTLEENDIAN(x)	(!SDL_AUDIO_ISBIGENDIAN(x))
SDL_AUDIO_ISUNSIGNED(x)	(!SDL_AUDIO_ISSIGNED(x))

Audio format flags

AUDIO_U8	unsigned 8-bit samples
AUDIO_S8	signed 8-bit samples
AUDIO_U16LSB	unsigned 16-bit samples
AUDIO_S16LSB	signed 16-bit samples
AUDIO_U16MSB	as above, but big-endian byte order
AUDIO_S16MSB	as above, but big-endian byte order
AUDIO_U16	AUDIO_U16LSB
AUDIO_S16	AUDIO_S16LSB

Defaults to LSB byte order.

int32 support

(New to SDL 1.3)

AUDIO_S32LSB	32-bit integer samples
AUDIO_S32MSB	as above, but big-endian byte order
AUDIO_S32	AUDIO_S32LSB

float32 support

(New to SDL 1.3)

AUDIO_F32LSB	32-bit floating point samples
AUDIO_F32MSB	as above, but big-endian byte order
AUDIO_F32	AUDIO_F32LSB

Native audio byte ordering

#if SDL_BYTEORDER == SDL_LIL_ENDIAN
#define AUDIO_U16SYS AUDIO_U16LSB
#define AUDIO_S16SYS AUDIO_S16LSB
#define AUDIO_S32SYS AUDIO_S32LSB
#define AUDIO_F32SYS AUDIO_F32LSB
#else
#define AUDIO_U16SYS AUDIO_U16MSB
#define AUDIO_S16SYS AUDIO_S16MSB
#define AUDIO_S32SYS AUDIO_S32MSB
#define AUDIO_F32SYS AUDIO_F32MSB
#endif

Code Examples

You can add your code example here

Remarks

Related Structures

SDL_StructureRemoveSectionIfEmpty

Related Functions

SDL_FunctionLeaveSectionIfEmpty

CategoryEnum

-  ⇤ ← Revision 1 as of 2009-12-13 17:54:10 → 
  Size: 1179
  Editor: SheenaSmith
  Comment: create page, add content (incomplete)
+   ← Revision 2 as of 2009-12-13 19:54:32 → ⇥
  Size: 2834
  Editor: SheenaSmith
  Comment: content added (still incomplete)
-Deletions are marked like this.
+Additions are marked like this.
 Line 5:
-A typedef that contains audio format flags.
+A typedef that contains audio format data and flags.
 Line 10:
+=== Bit Meanings ===
-Line 22:
+Line 23:
-''OR''
+''OR it could look like this''
-Line 30:
+Line 31:
-||value||description||
||value||description||
||value||description||
+=== Audio flags ===
||SDL_AUDIO_MASK_BITSIZE||(0xFF)||
||SDL_AUDIO_MASK_DATATYPE||(1<<8)||
||SDL_AUDIO_MASK_ENDIAN||(1<<12)||
||SDL_AUDIO_MASK_SIGNED||(1<<15)||
||SDL_AUDIO_BITSIZE(x)||(x & SDL_AUDIO_MASK_BITSIZE)||
||SDL_AUDIO_ISFLOAT(x)||(x & SDL_AUDIO_MASK_DATATYPE)||
||SDL_AUDIO_ISBIGENDIAN(x)||(x & SDL_AUDIO_MASK_ENDIAN)||
||SDL_AUDIO_ISSIGNED(x)||(x & SDL_AUDIO_MASK_SIGNED)||
||SDL_AUDIO_ISINT(x)||(!SDL_AUDIO_ISFLOAT(x))||
||SDL_AUDIO_ISLITTLEENDIAN(x)||(!SDL_AUDIO_ISBIGENDIAN(x))||
||SDL_AUDIO_ISUNSIGNED(x)||(!SDL_AUDIO_ISSIGNED(x))||

=== Audio format flags ===
||AUDIO_U8||unsigned 8-bit samples||
||AUDIO_S8||signed 8-bit samples||
||AUDIO_U16LSB||unsigned 16-bit samples||
||AUDIO_S16LSB||signed 16-bit samples||
||AUDIO_U16MSB||as above, but big-endian byte order||
||AUDIO_S16MSB||as above, but big-endian byte order||
||AUDIO_U16||AUDIO_U16LSB||
||AUDIO_S16||AUDIO_S16LSB||
Defaults to LSB byte order.

=== int32 support ===
(New to SDL 1.3)
||AUDIO_S32LSB||32-bit integer samples||
||AUDIO_S32MSB||as above, but big-endian byte order||
||AUDIO_S32||AUDIO_S32LSB||

=== float32 support ===
(New to SDL 1.3)
||AUDIO_F32LSB||32-bit floating point samples||
||AUDIO_F32MSB||as above, but big-endian byte order||
||AUDIO_F32||AUDIO_F32LSB||

=== Native audio byte ordering ===
{{{
#if SDL_BYTEORDER == SDL_LIL_ENDIAN
#define AUDIO_U16SYS AUDIO_U16LSB
#define AUDIO_S16SYS AUDIO_S16LSB
#define AUDIO_S32SYS AUDIO_S32LSB
#define AUDIO_F32SYS AUDIO_F32LSB
#else
#define AUDIO_U16SYS AUDIO_U16MSB
#define AUDIO_S16SYS AUDIO_S16MSB
#define AUDIO_S32SYS AUDIO_S32MSB
#define AUDIO_F32SYS AUDIO_F32MSB
#endif
}}}

Wiki Navigation

Wiki Page Content