zduke/VOC.TXT
Rachael Alexanderson 129a83b4e4 - import
2020-07-17 04:59:23 -04:00

130 lines
5 KiB
Text

Creative Voice (VOC) file format
--------------------------------
~From: galt@dsd.es.com
(byte numbers are hex!)
HEADER (bytes 00-19)
Series of DATA BLOCKS (bytes 1A+) [Must end w/ Terminator Block]
- ---------------------------------------------------------------
HEADER:
=======
byte # Description
------ ------------------------------------------
00-12 "Creative Voice File"
13 1A (eof to abort printing of file)
14-15 Offset of first datablock in .voc file (std 1A 00
in Intel Notation)
16-17 Version number (minor,major) (VOC-HDR puts 0A 01)
18-19 1's Comp of Ver. # + 1234h (VOC-HDR puts 29 11)
- ---------------------------------------------------------------
DATA BLOCK:
===========
Data Block: TYPE(1-byte), SIZE(3-bytes), INFO(0+ bytes)
NOTE: Terminator Block is an exception -- it has only the TYPE byte.
TYPE Description Size (3-byte int) Info
---- ----------- ----------------- -----------------------
00 Terminator (NONE) (NONE)
01 Sound data 2+length of data *
02 Sound continue length of data Voice Data
03 Silence 3 **
04 Marker 2 Marker# (2 bytes)
05 ASCII length of string null terminated string
06 Repeat 2 Count# (2 bytes)
07 End repeat 0 (NONE)
08 Extended 4 ***
*Sound Info Format: **Silence Info Format:
--------------------- ----------------------------
00 Sample Rate 00-01 Length of silence - 1
01 Compression Type 02 Sample Rate
02+ Voice Data
***Extended Info Format:
---------------------
00-01 Time Constant: Mono: 65536 - (256000000/sample_rate)
Stereo: 65536 - (25600000/(2*sample_rate))
02 Pack
03 Mode: 0 = mono
1 = stereo
Marker# -- Driver keeps the most recent marker in a status byte
Count# -- Number of repetitions + 1
Count# may be 1 to FFFE for 0 - FFFD repetitions
or FFFF for endless repetitions
Sample Rate -- SR byte = 256-(1000000/sample_rate)
Length of silence -- in units of sampling cycle
Compression Type -- of voice data
8-bits = 0
4-bits = 1
2.6-bits = 2
2-bits = 3
Multi DAC = 3+(# of channels) [interesting--
this isn't in the developer's manual]
---------------------------------------------------------------------------------
Addendum submitted by Votis Kokavessis:
After some experimenting with .VOC files I found out that there is a Data Block Type 9, which is not covered in the VOC.TXT file. Here is what I was able to discover about this block type:
TYPE: 09
SIZE: 12 + length of data
INFO: 12 (twelve) bytes
INFO STRUCTURE:
Bytes 0-1: (Word) Sample Rate (e.g. 44100)
Bytes 2-3: zero (could be that bytes 0-3 are a DWord for Sample Rate)
Byte 4: Sample Size in bits (e.g. 16)
Byte 5: Number of channels (e.g. 1 for mono, 2 for stereo)
Byte 6: Unknown (equal to 4 in all files I examined)
Bytes 7-11: zero
----------------------------------------------------------------------------------
Detailed description of new data blocks (VOC files version 1.20 and above):
(Source is fax from Barry Boone at Creative Labs, 405/742-6622)
BLOCK 8 - digitized sound attribute extension, must preceed block 1.
Used to define stereo, 8 bit audio
BYTE bBlockID; // = 8
BYTE nBlockLen[3]; // 3 byte length
WORD wTimeConstant; // time constant = same as block 1
BYTE bPackMethod; // same as in block 1
BYTE bVoiceMode; // 0-mono, 1-stereo
Data is stored left, right
BLOCK 9 - data block that supersedes blocks 1 and 8.
Used for stereo, 16 bit.
BYTE bBlockID; // = 9
BYTE nBlockLen[3]; // length 12 plus length of sound
DWORD dwSamplesPerSec; // samples per second, not time const.
BYTE bBitsPerSample; // e.g., 8 or 16
BYTE bChannels; // 1 for mono, 2 for stereo
WORD wFormat; // see below
BYTE reserved[4]; // pad to make block w/o data
// have a size of 16 bytes
Valid values of wFormat are:
0x0000 8-bit unsigned PCM
0x0001 Creative 8-bit to 4-bit ADPCM
0x0002 Creative 8-bit to 3-bit ADPCM
0x0003 Creative 8-bit to 2-bit ADPCM
0x0004 16-bit signed PCM
0x0006 CCITT a-Law
0x0007 CCITT u-Law
0x02000 Creative 16-bit to 4-bit ADPCM
Data is stored left, right