Skip to content

VGM logging help - Atari Off the Wall

Technical discussion about the VGM format, and all the software you need to handle VGM files.

Moderator: Staff

  • i86time Offline
  • Posts: 15
  • Joined: 2023-02-05, 8:30:55

Post by i86time »

ValleyBell wrote:You're doing the volume comparision the wrong way.
You should compare the VGM logged by M1 with the VGM logged by MAME. The volume should be the same.

VGMPlay's default volume is often a bit higher than those of other emulators.
If you want the VGM's volume to be lower, you can use the "vgm_ptch" tool to reduce it.

Code: Select all

vgm_ptch -SetVolMod:0.5 "file.vgm"
Sorry if what I wrote was unclear, but I was comparing the M1 VGM to the MAME VGM, I just output both to WAV so it could be visualized in a post. I thought it might be how the winamp plugin was handling the wav out, but the visual EQ bars and the volume was noticeably louder on the MAME one.

Thank you for that info on vgm_ptch, I didn't see anything about it doing any level adjustment in the readme file. It worked great and I should be able to match the levels. I had thought once the VGM was logged, the clipping would remain, but then I realized the VGM is essentially instructions for how to play back the music. I'm learning... slowly, but I'm learning.

Thanks again for everyone's help with this.
  • i86time Offline
  • Posts: 15
  • Joined: 2023-02-05, 8:30:55

Post by i86time »

Thanks again for the help with cheat script and recommendations. I've logged all the sounds and am now looping the level music. There are 12 songs that repeat throughout the game, with varying loop lengths. I've gone through them but am looking for some input.

Track 46 (2Eh) has the "instruments" spread out over 5 channels (drums/percussion on 1, 2 & 5), synth organ on 3 and synth horn on 4. The issue is that they are offset from each other and have different loop lengths that are not clean multiples of each other; taken from the individual channel disk writer outputs: 177259, 1134035, 1736527, 4751286 and 168319 samples. By my calculation, its just shy of 1 million years to play a true loop. In cases like this, what is generally done? Set the longest sample length as the loop length (though some instruments may clash at the loop point) or just create a fixed length file of two loops of the longest sample?

The second issue is what is the max preferred song length?. Track 32 (20h) has a very long loop, almost 3.5 hrs, where the tempo changes multiple times, starting off moderate, moving to very fast, then very slow, then moderate before starting over again; it does this twice before it completes a true loop and does change up the music, not just the speed. I venture that it's impossible for a player (without MAME cheats) to play anywhere long enough to hear the total track. But since the music is there, why not log it? What is the usual practice for this situation?

Post by Kaminari »

In case of dynamic music or asymmetrical loops, personally I would do as if I were in charge of an official OST -- I would make a choice and settle for a specific track duration, with a simple fadeout and without any loop. There is no way I would listen to a 3h tune.

VGM is not a preservation format, it's a format to play music.
  • i86time Offline
  • Posts: 15
  • Joined: 2023-02-05, 8:30:55

Post by i86time »

I have looped all but the 2 music tracks noted above. For the one that does not cleanly loop all channels/instruments, I'd like to end the track with a fade out after two of the longest channel loops. However, if I use vgm_trim without a loop point, it just ends the track without a fade.

For the other long track, I'd like to fade out/in as the music changes. Is that possible with any of the vgm tools?

EDIT: I see that looping is set in the playback app, so I am guessing there's no way to fade in/out within a track or to force a fade on a track without a set loop. If that is correct, I'm interested in suggestions on how to proceed. Perhaps append a few seconds of silence, set the loop start to the silence start?
  • i86time Offline
  • Posts: 15
  • Joined: 2023-02-05, 8:30:55

Post by i86time »

Well, about time for my weekly post/question. I've logged and looped everything, but have 2 remaining issues.
First, I noticed some tracks don't play at the correct speed. See attached file for the Wave 3 Complete jingle.
1 is a mic recording of my machine.
2 is a rip from this YT vid (https://www.youtube.com/watch?v=7G2neieUP_Q&t=1614s) which is fairly close to what my machine plays
3 is logged from MAME VGM and runs much faster than both
4 is logged from Bridge M1 (since M1 VGM would not log this track) and is much slower.

Of the tracks I've noticed that seemed different, they are all the wave complete jingles. Any ideas what might be causing it? Is there some setting in MAME/MAME VGM I might have missed? Other than these 4 or so tracks, everything else seems OK.

Second issue is that there are some sound FX I cannot ID. Is there a simple tutorial on the MAME debugger out there I can use to set up something where after a sound is called, it will pause gameplay and identify which sound?
Attachments
OtW_W3C.zip
(457.89 KiB) Downloaded 37 times
  • fever500 Offline
  • Posts: 56
  • Joined: 2022-06-12, 17:08:56
  • Location: FRANCE

Post by fever500 »

Can you send me a savestate when those SFX play?
  • i86time Offline
  • Posts: 15
  • Joined: 2023-02-05, 8:30:55

Post by i86time »

Thanks to a great deal of help from fever500, I have all the tracks logged, trimmed and tagged. One issue is, I was optimizing with vgm_sro and vgm_cmp -justtmr on a flow basis as I finished tracks. But as I started some weeks ago, I cannot remember if I completed it for all tracks. Is there a way to determine which tracks are optimized and which tracks are not? Also, what is needed when I submit the pack, just all tracks in .vgz, a m3u playlist, info file and splash screen shot? Can I use a screen shot from the internet or does it need to be "original"?
  • User avatar
  • ValleyBell Offline
  • Posts: 4768
  • Joined: 2011-12-01, 20:20:07
  • Location: Germany

Post by ValleyBell »

i86time wrote:Is there a way to determine which tracks are optimized and which tracks are not?
Just run the optimization tools again. If the VGMs are already optimized, they will write no new file.
i86time wrote:Also, what is needed when I submit the pack, just all tracks in .vgz, a m3u playlist, info file and splash screen shot? Can I use a screen shot from the internet or does it need to be "original"?
  • VGMs (as .vgm or .vgz)
  • playlist (.m3u)
  • screenshot (.png), usually taken from the title screen
    Put in multiple screenshots if there are different releases and the title screens are looking different. (different copyright text is considered "looking different")
    No screenshots from the internet, please. Those are may be blurry or have JPG artifacts.
  • description file (.txt)
  • For rules regarding naming and formatting, see the Submission Rules post. It has also a link to the description file template.
Post Reply