Important: Inside Macintosh: Sound is deprecated as of Mac OS X v10.5. For new audio development in Mac OS X, use Core Audio. See the Audio page in the ADC Reference Library.
Exp1to6
You can use theExp1to6
procedure to expand a buffer of sound samples you previously have compressed with theComp6to1
procedure.
PROCEDURE Exp1to6 (inBuffer: Ptr; outBuffer: Ptr; cnt: LongInt; inState: Ptr; outState: Ptr; numChannels: LongInt; whichChannel: LongInt);
inBuffer
- A pointer to a buffer of packets to be expanded.
outBuffer
- A pointer to a buffer where the expanded samples will be written.
cnt
- The number of packets to expand.
inState
- A pointer to a 128-byte buffer from which the input state of the algorithm is read, or
NIL
. To initialize the algorithm, this buffer should be filled with zeros.outState
- A pointer to a 128-byte buffer to which the output state of the algorithm is written, or
NIL
. This buffer might be the same as that specified by theinState
parameter.numChannels
- The number of channels in the buffer pointed to by the
inBuffer
parameter.whichChannel
- The channel to expand, when
numChannels
is greater than 1. This parameter must be in the range of 1 tonumChannels
.DESCRIPTION
TheExp1to6
procedure expandscnt
packets of sound stored in the buffer specified byinBuffer
and places the result in the buffer specified byoutBuffer
, whose size must be at leastcnt
packets * 1 byte per packet * 6, orcnt * 6
bytes. IfnumChannels
is greater than 1, then the compressed sound must be stored in interleaved format on a packet basis. TheExp1to6
procedure works just like theExp1to3
procedure, but expands 1-byte packets rather than 2-byte packets.SPECIAL CONSIDERATIONS
Because theExp1to6
procedure might allocate memory, you should not call it at interrupt time.ASSEMBLY-LANGUAGE INFORMATION
The trap macro and routine selector for theExp1to6
procedure are
Trap macro Selector _SoundDispatch $00100010