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Sampled sound format

                    IFF FORM "SAMP" Sampled Sound

 Date:   Dec 3,1989
 From:   Jim Fiore and Jeff Glatt, dissidents

The form "SAMP" is a file format used to store sampled sound data in some
ways like the current standard, "8SVX". Unlike "8SVX", this new format is
not restricted to 8 bit sample data. There can be more than one waveform
per octave, and the lengths of different waveforms do not have to be
factors of 2. In fact, the lengths (waveform size) and playback mapping
(which musical notes each waveform will "play") are independently
determined for each wave- form. Furthermore, this format takes into
account the MIDI sample dump stan- dard (the defacto standard for musical
sample storage), while also incorpo- rating the ability to store Amiga
specific info (for example, the sample data that might be sent to an audio
channel which is modulating another channel).

Although this form can be used to store "sound effects" (typically oneShot
sounds played at a set pitch), it is primarily intended to correct the
many deficiencies of the "8SVX" form in regards to musical sampling.
Because the emphasis is on musical sampling, this format relies on the
MIDI (Musical Instrument Digital Interface) method of describing "sound
events" as does virtually all currently manufactured, musical samplers. In
addition, it at- tempts to incorporate features found on many professional
music samplers, in anticipation that future Amiga models will implement 16
bit sampling, and thus be able to achieve this level of performance.
Because this format is more complex than "8SVX", programming examples to
demonstrate the use of this format have been included in both C and
assembly. Also, a library of func- tions to read and write SAMP files is
available, with example applications.

SEMANTICS: When MIDI literature talks about a sample, usually it means a
collection of many sample points that make up what we call a "wave".

 Similarities and Differences from the 8SVX Form 
 The SAMP Header 
 The MHDR Chunk 
 The NAME Chunk 
 The BODY Chunk 
 Structure of an Individual Sample Point 
 The Waveheader Explained 
 MIDI Velocity vs. Amiga Channel Volume 
 An EGpoint (Envelope Generator) 
 Additional User Data Section 
 Converting Midi Sample Dump to SAMP 
 Interpreting the Playmode 
 Making A Transpose Table 
 Making the Velocity Table 
 The Instrument Type 
 The Order of the Chunks 
 Filename Conventions 
 Why Does Anyone Need Such a Complicated File? 

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