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‹sample›

Allows to embed sample data directly in SFZ files (Rapture).

Example #

<region> sample=mysample.wav
<sample> name=mysample.wav data=[encoded-content-of-mysample.wav]

The content encoding is an alphabet mapping of 256 entries that map to each byte. (in the encoding, a WAV file is immediately recognizable by having its four byte “RIFF” header encoded to “|spp”)

This C source file can be compiled to convert a wav file to an embedded sample.

Decoding #

The decoding algorithm is as follows:

  • Loop while there is an input byte b1
    • if b1 is the end marker $24, stop reading
    • if b1 is ‘\r’ ($0D) or ‘\n’ ($0A), discard it
    • if b1 is the escape character ‘=’ ($3D),
      • extract the next byte b2, and compute the next output byte as (b2+$C0)%256
    • otherwise, compute the next output byte as (b2+$D6)%256

Encoding #

  • Loop while there is an input byte b1
    • if (b1+$2A)%256 is one of the “forbidden characters” ($3D, $00, $09, $0A, $0D, $24)
      • output the escape character $3D, and then output the byte (b1+$40)%256
    • otherwise, output (b1+$2A)%256
  • Output the end marker $24

Alphabet #

The alphabet used for the coding is as following:

  $00 $10 $20 $30 $40 $50 $60 $70 $80 $90 $A0 $B0 $C0 $D0 $E0 $F0
$00 $2A $3A $4A $5A $6A $7A $8A $9A $AA $BA $CA $DA $EA $FA $3D20 $1A
$01 $2B $3B $4B $5B $6B $7B $8B $9B $AB $BB $CB $DB $EB $FB $0B $1B
$02 $2C $3C $4C $5C $6C $7C $8C $9C $AC $BC $CC $DC $EC $FC $0C $1C
$03 $2D $3D53 $4D $5D $6D $7D $8D $9D $AD $BD $CD $DD $ED $FD $3D23 $1D
$04 $2E $3E $4E $5E $6E $7E $8E $9E $AE $BE $CE $DE $EE $FE $0E $1E
$05 $2F $3F $4F $5F $6F $7F $8F $9F $AF $BF $CF $DF $EF $FF $0F $1F
$06 $30 $40 $50 $60 $70 $80 $90 $A0 $B0 $C0 $D0 $E0 $F0 $3D16 $10 $20
$07 $31 $41 $51 $61 $71 $81 $91 $A1 $B1 $C1 $D1 $E1 $F1 $01 $11 $21
$08 $32 $42 $52 $62 $72 $82 $92 $A2 $B2 $C2 $D2 $E2 $F2 $02 $12 $22
$09 $33 $43 $53 $63 $73 $83 $93 $A3 $B3 $C3 $D3 $E3 $F3 $03 $13 $23
$0A $34 $44 $54 $64 $74 $84 $94 $A4 $B4 $C4 $D4 $E4 $F4 $04 $14 $3D3A
$0B $35 $45 $55 $65 $75 $85 $95 $A5 $B5 $C5 $D5 $E5 $F5 $05 $15 $25
$0C $36 $46 $56 $66 $76 $86 $96 $A6 $B6 $C6 $D6 $E6 $F6 $06 $16 $26
$0D $37 $47 $57 $67 $77 $87 $97 $A7 $B7 $C7 $D7 $E7 $F7 $07 $17 $27
$0E $38 $48 $58 $68 $78 $88 $98 $A8 $B8 $C8 $D8 $E8 $F8 $08 $18 $28
$0F $39 $49 $59 $69 $79 $89 $99 $A9 $B9 $C9 $D9 $E9 $F9 $3D1F $19 $29