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{
-> Does anyone know how to read a .MOD file in pascal? Not play a .MOD
-> just read all the pattern and track info. All the notes and stuff and
-> effects. I dont care about the instrument data and all that.
-> If so, could you please post a source or something?
I wrote a MOD sample ripper, thought about distributing it, it's rather
nice. I wrote it in TP. I have some doc files on MOD's you might be
interested in...
Subject: Amiga modules formaat
Have you ever wondered how a Protracker 1.1B module is built up?
Well, here's the...
Protracker 1.1B Song/Module Format:
-----------------------------------
Offset Bytes Description
------ ----- -----------
0 20 Songname. Remember to put trailing null bytes at the
end...
Information for sample 1-31:
Offset Bytes Description
------ ----- -----------
20 22 Samplename for sample 1. Pad with null bytes.
42 2 Samplelength for sample 1. Stored as number of words.
Multiply by two to get real sample length in bytes.
44 1 Lower four bits are the finetune value, stored as a
signed
four bit number. The upper four bits are not used, and
should be set to zero.
Value: Finetune:
0 0
1 +1
2 +2
3 +3
4 +4
5 +5
6 +6
7 +7
8 -8
9 -7
A -6
B -5
C -4
D -3
E -2
F -1
45 1 Volume for sample 1. Range is $00-$40, or 0-64 decimal.
46 2 Repeat point for sample 1. Stored as number of words
offset
from start of sample. Multiply by two to get offset in
bytes.
48 2 Repeat Length for sample 1. Stored as number of words in
loop. Multiply by two to get replen in bytes.
Information for the next 30 samples starts here. It's just like the
info for
sample 1.
Offset Bytes Description
------ ----- -----------
50 30 Sample 2...
80 30 Sample 3...
.
.
.
890 30 Sample 30...
920 30 Sample 31...
Offset Bytes Description
------ ----- -----------
950 1 Songlength. Range is 1-128.
951 1 Well... this little byte here is set to 127, so that old
trackers will search through all patterns when loading.
Noisetracker uses this byte for restart, but we don't.
952 128 Song positions 0-127. Each hold a number from 0-63 that
tells the tracker what pattern to play at that position.
1080 4 The four letters "M.K." - This is something Mahoney &
Kaktus
inserted when they increased the number of samples from
15 to 31. If it's not there, the module/song uses 15
samples
or the text has been removed to make the module harder
to
rip. Startrekker puts "FLT4" or "FLT8" there instead.
Offset Bytes Description
------ ----- -----------
1084 1024 Data for pattern 00.
.
.
.
xxxx Number of patterns stored is equal to the highest patternnumber
in the song position table (at offset 952-1079).
Each note is stored as 4 bytes, and all four notes at each position in
the pattern are stored after each other.
00 - chan1 chan2 chan3 chan4
01 - chan1 chan2 chan3 chan4
02 - chan1 chan2 chan3 chan4
etc.
Info for each note:
_____byte 1_____ byte2_ _____byte 3_____ byte4_
/ \ / \ / \ / \
0000 0000-00000000 0000 0000-00000000
Upper four 12 bits for Lower four Effect command.
bits of sam- note period. bits of sam-
ple number. ple number.
Periodtable for Tuning 0, Normal
C-1 to B-1 : 856,808,762,720,678,640,604,570,538,508,480,453
C-2 to B-2 : 428,404,381,360,339,320,302,285,269,254,240,226
C-3 to B-3 : 214,202,190,180,170,160,151,143,135,127,120,113
To determine what note to show, scan through the table until you find
the same period as the one stored in byte 1-2. Use the index to look
up in a notenames table.
This is the data stored in a normal song. A packed song starts with the
four letters "PACK", but i don't know how the song is packed: You can
get the source code for the cruncher/decruncher from us if you need it,
but I don't understand it; I've just ripped it from another tracker...
In a module, all the samples are stored right after the patterndata.
To determine where a sample starts and stops, you use the sampleinfo
structures in the beginning of the file (from offset 20). Take a look
at the mt_init routine in the playroutine, and you'll see just how it
is done.
Lars "ZAP" Hamre/Amiga Freelancers
*** THE END ***
I believe that file goes under the name of MODFORM.DOC, not sure. Not
even sure where I got it. Anyway, enjoy.
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