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Extend comments documenting various supported audio formats and mixer devices.

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Reviewed by:    ru, cg
Approved by:    cg
Obtained from:  4Front's OSS Programming Guide
MFC after:	2 weeks
This commit is contained in:
Maxim Sobolev 2001-08-18 15:07:51 +00:00
parent 1139160ec0
commit 9ee52e44f4
1 changed files with 49 additions and 32 deletions
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81
sys/sys/soundcard.h
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@ -138,34 +138,45 @@ struct snd_size {
* capability, and bit 29 (RO) to indicate that the card supports/
* needs different formats on capture & playback channels.
* Bit 29 (RW) is used to indicate/ask stereo.
*
* The number of bits required to store the sample is:
* o 4 bits for the IDA ADPCM format,
* o 8 bits for 8-bit formats, mu-law and A-law,
* o 16 bits for the 16-bit formats, and
* o 32 bits for the 24/32-bit formats.
* o undefined for the MPEG audio format.
*/
# define AFMT_QUERY 0x00000000 /* Return current fmt */
# define AFMT_MU_LAW 0x00000001
# define AFMT_A_LAW 0x00000002
# define AFMT_IMA_ADPCM 0x00000004
# define AFMT_U8 0x00000008
# define AFMT_S16_LE 0x00000010 /* Little endian signed 16*/
# define AFMT_S16_BE 0x00000020 /* Big endian signed 16 */
# define AFMT_S8 0x00000040
# define AFMT_U16_LE 0x00000080 /* Little endian U16 */
# define AFMT_U16_BE 0x00000100 /* Big endian U16 */
# define AFMT_MPEG 0x00000200 /* MPEG (2) audio */
# define AFMT_AC3 0x00000400 /* Dolby Digital AC3 */
#define AFMT_QUERY 0x00000000 /* Return current format */
#define AFMT_MU_LAW 0x00000001 /* Logarithmic mu-law */
#define AFMT_A_LAW 0x00000002 /* Logarithmic A-law */
#define AFMT_IMA_ADPCM 0x00000004 /* A 4:1 compressed format where 16-bit
* squence represented using the
* the average 4 bits per sample */
#define AFMT_U8 0x00000008 /* Unsigned 8-bit */
#define AFMT_S16_LE 0x00000010 /* Little endian signed 16-bit */
#define AFMT_S16_BE 0x00000020 /* Big endian signed 16-bit */
#define AFMT_S8 0x00000040 /* Signed 8-bit */
#define AFMT_U16_LE 0x00000080 /* Little endian unsigned 16-bit */
#define AFMT_U16_BE 0x00000100 /* Big endian unsigned 16-bit */
#define AFMT_MPEG 0x00000200 /* MPEG MP2/MP3 audio */
#define AFMT_AC3 0x00000400 /* Dolby Digital AC3 */
/*
* may not have all bits significant:
* 32-bit formats below used for 24-bit audio data where the data is stored
* in the 24 most significant bits and the least significant bits are not used
* (should be set to 0).
*/
# define AFMT_S32_LE 0x00001000 /* Little endian signed 32 */
# define AFMT_S32_BE 0x00002000 /* big endian signed 32 */
# define AFMT_U32_LE 0x00004000 /* Little endian unsigned 32 */
# define AFMT_U32_BE 0x00008000 /* big endian unsigned 32 */
#define AFMT_S32_LE 0x00001000 /* Little endian signed 32-bit */
#define AFMT_S32_BE 0x00002000 /* Big endian signed 32-bit */
#define AFMT_U32_LE 0x00004000 /* Little endian unsigned 32-bit */
#define AFMT_U32_BE 0x00008000 /* Big endian unsigned 32-bit */
# define AFMT_STEREO 0x10000000 /* can do/want stereo */
#define AFMT_STEREO 0x10000000 /* can do/want stereo */
/*
* the following are really capabilities
*/
# define AFMT_WEIRD 0x20000000 /* weird hardware... */
#define AFMT_WEIRD 0x20000000 /* weird hardware... */
/*
* AFMT_WEIRD reports that the hardware might need to operate
* with different formats in the playback and capture
@ -174,7 +185,7 @@ struct snd_size {
* direction and S16 in the other one, and applications should
* be aware of this limitation.
*/
# define AFMT_FULLDUPLEX 0x80000000 /* can do full duplex */
#define AFMT_FULLDUPLEX 0x80000000 /* can do full duplex */
/*
* The following structure is used to get/set format and sampling rate.
@ -878,18 +889,24 @@ typedef struct copr_msg {
*/
#define SOUND_MIXER_NRDEVICES 25
#define SOUND_MIXER_VOLUME 0
#define SOUND_MIXER_BASS 1
#define SOUND_MIXER_TREBLE 2
#define SOUND_MIXER_SYNTH 3
#define SOUND_MIXER_PCM 4
#define SOUND_MIXER_SPEAKER 5
#define SOUND_MIXER_LINE 6
#define SOUND_MIXER_MIC 7
#define SOUND_MIXER_CD 8
#define SOUND_MIXER_IMIX 9 /* Recording monitor */
#define SOUND_MIXER_ALTPCM 10
#define SOUND_MIXER_RECLEV 11 /* Recording level */
#define SOUND_MIXER_VOLUME 0 /* Master output level */
#define SOUND_MIXER_BASS 1 /* Treble level of all output channels */
#define SOUND_MIXER_TREBLE 2 /* Bass level of all output channels */
#define SOUND_MIXER_SYNTH 3 /* Volume of synthesier input */
#define SOUND_MIXER_PCM 4 /* Output level for the audio device */
#define SOUND_MIXER_SPEAKER 5 /* Output level for the PC speaker
* signals */
#define SOUND_MIXER_LINE 6 /* Volume level for the line in jack */
#define SOUND_MIXER_MIC 7 /* Volume for the signal coming from
* the microphone jack */
#define SOUND_MIXER_CD 8 /* Volume level for the input signal
* connected to the CD audio input */
#define SOUND_MIXER_IMIX 9 /* Recording monitor. It controls the
* output volume of the selected
* recording sources while recording */
#define SOUND_MIXER_ALTPCM 10 /* Volume of the alternative codec
* device */
#define SOUND_MIXER_RECLEV 11 /* Global recording level */
#define SOUND_MIXER_IGAIN 12 /* Input gain */
#define SOUND_MIXER_OGAIN 13 /* Output gain */
/*