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IDProjectCategoryView StatusLast Update
0001036OpenMPT[All Projects] Playback Compatibilitypublic2018-02-17 18:27
ReporterwertstahlAssigned ToSaga Musix 
Status assignedResolutionopen 
Platformx64OSWindowsOS Version7
Product VersionOpenMPT / libopenmpt 0.3.1 (upgrade first) 
Target VersionOpenMPT (goals)Fixed in Version 
Summary0001036: OctaMED 5.04 (Amiga) Mod's MMD2 format opens with incorrect and unfixable playback speed

OctaMED module opens on Amiga OctaMeD 5.04 correctly with BPM 85 / Timebase 8, plays OK with 11 Channels (Samples+Midi)
Opens in openMPT but has
-- incorrect BPM 170 / Timebase 6 in format MMD2
--- opened as MMD2, regardless if changed to IT, XM, openMPT module mode: timining readjustment impossible (weird results)
--- weird sample looping effects upon format/timing change
--- sample loop and replay timing messed up (at first i thought it was some auto shuffle option)

opened as MMD1 and MMD0:
-- replay correctly, but ofcourse additional (>4) channels are missing -> thus no solution, but audio reference for debugging

Note: MMD2 has a flexible track count, 16bit sample support and midi support!

Tested with X32 and X64 binary.

[Note: as a coder i might add : the original 85 bmp *2 = 170 bmp, so ...]

Steps To Reproduce

open attached file
-- "09m23-Tag danach-mmd2" - this tune ALSO uses midi instruments ! -
in most recent openMPT, and play first pattern, amiga samples are offbeat, wrong speed stetting (BPM 170/Timebase 6)

open attached file
-- "09m23-Tag danach--mmd1" - this tune ALSO uses midi instruments ! -
in most recent openMPT and play first pattern:
everything is in OK, but , due to file format restrictions this is no solution, since only 4 channels are present.
speed still displayed wrong (BPM 170 / Timebase 6 : should be BPM 85 / Timebase 8) but the samples play correctly

TagsNo tags attached.
Has the bug occurred in previous versions?probably yes
Tested code revision (in case you know it)


related to 0000071 assignedSaga Musix Faulty octamed importer 


Saga Musix

Saga Musix

2017-10-01 01:00

administrator   ~0003272

Yeah, OctaMED support has been somewhat broken/incomplete for a long time (see related issue). It needs to be rewritten entirely at some point (probably using the libxmp code as a base). I have little understanding of the different tempo modes in OctaMED so I'm not sure I would be able to fix it before that rewrite...

Saga Musix

Saga Musix

2017-10-01 01:01

administrator   ~0003273

Also, the attachments are missing, please, attach the modules in a 7z/zip file. :)



2017-10-01 08:58

reporter   ~0003274

Here are the attachments again. Oh and it would be very very nice if a fix "happened" because i will soon be done with most of the non-hybrid (Amiga Samples only) 8-Track works, now looking at quite a bunch hybrid (Samples+Midi) albums. Musnt you just look at the Amiga replay routine? Were'nt there always source code files for that included to tease game developers?
(I just checked, and there is a standalone OctaMedPlayer - its an exe but only 21k! :) (26,497 bytes) (26,462 bytes)
Saga Musix

Saga Musix

2017-10-01 09:32

administrator   ~0003275

Musnt you just look at the Amiga replay routine?

"Just"... typically this code is not exactly well documented and I have no realy knowledge of 68k assembly or even Amiga programming.



2017-10-01 10:23

reporter   ~0003276

I just found out, that deliplayer 2 can correctly open+replay these files... is that helpful?

Saga Musix

Saga Musix

2017-10-01 10:27

administrator   ~0003277

DeliPlayer typically uses EaglePlayers, so no. You could check if xmp (not XMPlay) plays them correctly, since that would be the most likely implementation I would base my re-implementation on. But I know that xmp is also not 100% accurate as MED is rather complicated.



2017-10-01 10:37

reporter   ~0003278

like this .dll for instance? can't these plugins be used to import stuff? (18,973 bytes)
Saga Musix

Saga Musix

2017-10-02 00:31

administrator   ~0003279

No, apart from things such as incompatible / questionable licenses, those player modules simply don't give us pattern data or other stuff we need for import. as I said, I need documentation, not random player libraries, and it's unlikely that there will be an immediate fix.



2017-10-02 22:54

reporter   ~0003283

what about this?



2017-10-02 22:55

reporter   ~0003284

this archive, i meant (49,149 bytes)


2017-10-02 23:12

reporter   ~0003285

or what about this? (11,833 bytes)


2017-10-02 23:21

reporter   ~0003286

and this library is flawed, i understand?

Saga Musix

Saga Musix

2017-10-03 14:12

administrator   ~0003289

That updated MED specification is useful, thanks. I only had one covering the older format revisions.
xmp may or may not be working regarding your issue, I know it's not perfect either but it may just as well work fine regarding the tempo.
Anyway, as mentioned, MED support has always been flaky so I don't see any reason for immediate action. If this matter is very important to you, you will have to consider contributing the fixed code yourself, because I won't have time or motivation to immediately fix it - for me there are much more important things that need to be fixed at the moment.



2017-10-03 21:20

reporter   ~0003291

Ok. After i sense a strong consistency in the hesitance regarding a desire to even look at the OctaMED problem, i did so, myself,... and... well... The trouble might be a little bigger than i originally expected - it is not only a tempo problem. I'll be looking into that now. See attached a Med Soundstudio (blue) screenshot and an openMPT screenshot. Funny that i didn't notice that at first, but it might be due to the fact that i don't really recognize a)Tracker-Tracks b)my own 20 year old MODs anymore.



2017-10-03 21:22

reporter (244,923 bytes)
Saga Musix

Saga Musix

2018-02-17 18:27

administrator   ~0003426

As a first step, the garbled patterns are now loaded correctly in OpenMPT However, the major rewrite of the MED loader which will fix even more issues will still take a while, since the format is really complex.

Issue History

Date Modified Username Field Change
2017-09-30 23:55 wertstahl New Issue
2017-10-01 00:58 Saga Musix Relationship added related to 0000071
2017-10-01 01:00 Saga Musix Note Added: 0003272
2017-10-01 01:01 Saga Musix Note Added: 0003273
2017-10-01 01:01 Saga Musix Priority urgent => normal
2017-10-01 08:58 wertstahl File Added:
2017-10-01 08:58 wertstahl File Added:
2017-10-01 08:58 wertstahl Note Added: 0003274
2017-10-01 09:32 Saga Musix Note Added: 0003275
2017-10-01 10:23 wertstahl Note Added: 0003276
2017-10-01 10:27 Saga Musix Note Added: 0003277
2017-10-01 10:37 wertstahl File Added:
2017-10-01 10:37 wertstahl Note Added: 0003278
2017-10-02 00:31 Saga Musix Note Added: 0003279
2017-10-02 22:54 wertstahl Note Added: 0003283
2017-10-02 22:55 wertstahl File Added:
2017-10-02 22:55 wertstahl Note Added: 0003284
2017-10-02 23:12 wertstahl File Added:
2017-10-02 23:12 wertstahl Note Added: 0003285
2017-10-02 23:21 wertstahl Note Added: 0003286
2017-10-03 14:12 Saga Musix Note Added: 0003289
2017-10-03 21:20 wertstahl Note Added: 0003291
2017-10-03 21:22 wertstahl File Added:
2018-02-04 18:02 Saga Musix Assigned To => Saga Musix
2018-02-04 18:02 Saga Musix Status new => assigned
2018-02-04 18:03 Saga Musix Target Version => OpenMPT (goals)
2018-02-17 18:27 Saga Musix Note Added: 0003426