Random audio inconsistencies

[Former user]

Original issue 196 created by thiagoalvesdealmeida on 2011-12-21T14:19:26.000Z:

This is a very rare issue that I wasn't able to reproduce, but since I experimented this three or four times on different occasions (with different games), I thought that maybe it's worth to report.

Sometimes I notice that the game will drop below 60fps. And it's not a slowdown of the game itself, since the music also becomes a little jerk. So, I have the impression that, for a brief moment, the emulator can't keep the framerate stable at 60fps.

As I said, it happens randomly and I wasn't able to reproduce it. I was playing "The Revenge of Shinobi" in the past 3 days and only one time I noticed this problem (playing the China Town level, and just during a few seconds).

I'm not sure if anybody else notice the same problem. It happens rarely and only for a few seconds, so it could be unoticeable to most people.

Maybe if there was a framerate counter it would be easier to spot this issue.

I'm using NTSC (TV, Wii and rom) and 240p video mode.

[Former user]

Comment # 1 originally posted by ekeeke31 on 2011-12-21T17:08:26.000Z:

I really doubt the emulator cannot handle full framerate in all situations, especially with the performance I measured on some games which were above 2x or 3x the expected framerate when removing the frame limit (i.e emulator running without waiting for sync).

Also, the fact Virtua Racing, which requirements have no equivalents with any genesis games (since it requires emulation of an additional CPU), is running fullspeed, tells me that that it would be illogical that a normal genesis game is taking too much cpu to emulate.

Finally, the fact it is not reproductible (i personally never experimented such frame drop) tells that this is not related to emulation of a specific part in a specific game which would require too much CPU time, otherwise it would happen everytime at the same spot.

Honestly, if this is not a huge slowdown but more an impression that it dropped from 60 to 58 fps, i think this is just what it is, an impression.

Othetwise, it might be related to the way the emulator is syncing itself: it is designed in a way that not a single frame should be missed (not even a few ones periodically like it is the case with most emulators on PC) neither any audio samples skipped. This requires very precise synchronization with Wii video AND audio hardware, while involving special techniques to keep multiple sound chips emulation in sync. As with all such stuff, there are approximations, and it's possible that in some very specific and rare cases, the synchronization fails and either accidentally slowdowns the emulator or fuck up the audio (as seen in another open issue i cannot reproduce).

The sync method is a little bit different when the emulator and Wii are running at different framerate (e.g emulating a NTSC genesis on a PAL Wii with TVMode forced to 50hz or the contrary), in the sense that emulation is now synced with audio hardware only, since a few frames are going to be dropped anyway. Since you have a NTSC Wii, you could first try to force Console Region to EUROPE, TV Mode to 60hz and see if you can reproduce heavy slowdowns.

[Former user]

Comment # 2 originally posted by thiagoalvesdealmeida on 2011-12-21T22:45:00.000Z:

Yes. To tell the true, it seems more like a syncing issue, and not a perfomance problem. Could be also only an impression, I don't know... I only reported this because I had the same impression more than one time. And to be more precise, what catch my attention was the sound (a bit jerky for a brief moment). I can't say if there was any problem with the video.

So, IF this is a real issue, it certainly related to syncing method. But since this is very rare... it's definitely not worth investigating.

I tried to reproduce the problem, but with no luck. Maybe it only happens after a certain amount of time and/or with some rare scenarios. Can't say.

Thanks for clarifying that.

[Former user]

Comment # 3 originally posted by thiagoalvesdealmeida on 2011-12-22T13:04:08.000Z:

By the way, I just noticed this issue again. It was definitely only a cracking in the sound - but I'm certain I heard it.

[Former user]

Comment # 4 originally posted by ekeeke31 on 2011-12-22T18:52:11.000Z:

Well, that won't help me much fixing something I cannot reproduce on my side.

Actually, I spent quite a lot of time fixing video skipping / audio crackling and even if there aren't perfect solutions to this very sensitive subject that is synchronization with asynchronous hardware, I am quite satisfied with the current result.

So, considering the issue ihappens completely randomly and very rarely, is apparently barely noticeable or at least obviously tied a lot to user's appreciation, I don't think I'm gonna spend any more time on this unless it's really spoiling emulation experience.

I leave the issue open though, so that other people might eventually join in with more usable inputs.

[Former user]

Comment # 5 originally posted by thiagoalvesdealmeida on 2011-12-22T19:53:17.000Z:

OK. I agree with you. It's not worth the trouble. Maybe it would be better to change the title of the issue, to reflect what it really is: a ocassional audio crackling.

[Former user]

Comment # 6 originally posted by thiagoalvesdealmeida on 2011-12-23T14:30:27.000Z:

Just to add more information... I think this problem is not as rare as I thought. I don't play very often, but sometimes, when I take a few hours to play, I notice the audio crackling.

I was playing Shinobi III yesterday without problem. But today, I noticed a ugly audio crackling that lasted for 4 seconds.

So, I would say I come across this problem often, considering that I don't play that much. It only happens in the last stages of the game (and not always, of course), so I would say it takes some time to happen.

[Former user]

Comment # 7 originally posted by ekeeke31 on 2011-12-23T16:27:15.000Z:

Well, I'm saying it's rare because I cannot reproduce it, because the audio/video code did not change since version 1.4.O (more than one year old !) and I only got 2 issues report on that matter so far so it could as well be specific to your setup or an hardware inconsistency ;-)

Although, if you have Low-Pass filter enabled, you could try to disable it since I remember noticing that in some situations it will result in temporary garbled sound for an unknown reason, probably a bug or a limitation of the filter code I'm using. Anyway, it's generally a good idea to give the emulators settings (System,Video,Audio) you are using when reporting an issue, since it gives me a better seeing of the situation. Also helps if you try to reproduce the issue with different setups, by changing key settings like High-Quality FM, Audio/Video filters, Render Mode, TV Mode, Borders, Console Region, etc...

[Former user]

Comment # 8 originally posted by ekeeke31 on 2011-12-23T16:27:34.000Z:

[Former user]

Comment # 9 originally posted by Icedus on 2011-12-23T17:20:06.000Z:

I have a similar thing happen with consistency in Sonic 3. You know how in some areas, having water on the screen makes the game flash some garbled graphics? Whenever that happens, the music seems to stall for a split second. The graphics thing happens on real hardware, but the music stays consistent and doesn't seem to skip. I have the latest release of the emulator, with all default settings, and I'm playing on an old CRT TV for emulation purposes. I wasn't sure whether to start a new issue about this, since it may be related to this one.

[Former user]

Comment # 10 originally posted by thiagoalvesdealmeida on 2011-12-23T17:29:52.000Z:

I'm using the default audio settings (filtering is off). Like I said, I'm using the Original video mode, and I always play at 60hz (using NTSC roms).

Trying to reproduce this issue with different setups is unviable, since it's very randomly and it would take a massive amount of time to test. I also know it almost impossibile at this point for you to fix it, since it's not easy to reproduce the bug - but it's a good thing to leave this issue open. Maybe some else can provide a better feedback.

But next time I play something, I will try to use Mednafen-wii to see if something wrong happens there.

[Former user]

Comment # 11 originally posted by ekeeke31 on 2011-12-23T22:40:31.000Z:

Mednafen-Wii probably uses a totally different interface for audio/video backends & sync so this won't help much. Also it's based on an older version of genesis plus which my current code has quite nothing more in common with. Anyway, I bet this is not an issue with emulation core or it would happen every time at the same spots, since emulation is quite deterministic.

@ Icedus: this seems different as you said it happens everytime you reach that spot. Could you upload a savestate so I could try reproducing it when i have some time.

[Former user]

Comment # 12 originally posted by ekeeke31 on 2012-01-17T21:40:37.000Z:

[Former user]

Comment # 13 originally posted by thiagoalvesdealmeida on 2012-01-22T20:25:24.000Z:

Just to add more information... I also noticed this problem with a Master System game.

[Former user]

Comment # 14 originally posted by ekeeke31 on 2012-01-22T21:59:41.000Z:

Fantastic, thank you for this very detailled information :-/ Could you at least give the name of the game or describe what happened exactly and when ?

[Former user]

Comment # 15 originally posted by thiagoalvesdealmeida on 2012-01-23T00:44:19.000Z:

It's the same issue I told you before. It's an audio crackling that happens randomly, most likely after the game is running for a while. It sure sounds like a sync problem, like Snes9x or Fceux had before it was fixed.

The game is Zillion (but it certanly happens with every game). When you have the time maybe you should play it until the end. Nice game. It will take sometime to beat it in one sit since there is no password, but it will probably give you the opportunity to hear the problem, since you will be listening to the same music for a long time.

My opinion is that maybe you should rethink the syncing method. Pushing slightly more than 48000 samples with Fceux fixed it's problem.

[Former user]

Comment # 16 originally posted by ekeeke31 on 2012-01-23T09:09:15.000Z:

I am not going to change the sync method for something that i never noticed on my side the whole time i tested the emulator and that you barely can't give details on how to reproduce since it seems inconsistent, rare and game-independant...

And no, it's not the same issue as other emulators and i already do the adjusted samplerate thing. Also i think the issue with those emulators was much more noticeable and repetitive.

Anyway, next version will provide an option to disable VSYNC and let emulator synchronize with audio hardware only like it does when TV mode does not match emulated video mode, which should fix any audio inconsistancies you are hearing.

Something you didn't mentionned: does the glitch you hear disappear by itself after a while (without you entering the menu or reinitializing game) ? In this case, how long is it hearable ? Isn't there anything consistent between 2 occurrences (duration of sound glitch, time played before it happens, ...)

[Former user]

Comment # 17 originally posted by thiagoalvesdealmeida on 2012-01-23T10:26:46.000Z:

The glitch disappear by itself after about 2 seconds.

About the consistent of the occurrences... They happen after playing for a while and I had the impression that sometimes the duration of sound glitch is longer than others occurrences, but I'm not sure.

I know that I should had provided more info, sorry. Maybe I could try to record the audio or something.

[Daniel Weiss]

Comment # 18 originally posted by danweiss on 2012-03-12T05:24:09.000Z:

I'm getting buffer underruns with the sound in Shining Force II. Usually, it happens after the emulator has been running for several minutes.

[Former user]

Comment # 19 originally posted by ekeeke31 on 2012-03-12T08:31:09.000Z:

As already asked, please give the audio & video settings you are using and also what kind of wii you have (PAL or NTSC) if you want me to find where the problem might be. Since I cannot reproduce this issue in any of these games, even when letting them run for hours, any informations you can provide is a plus, including video recording of the issue when possible.

[Former user]

Comment # 20 originally posted by ekeeke31 on 2012-03-12T21:52:39.000Z:

Here is a test version which logs audio/video timings and might help figure what is going wrong on your setup.

1) first make sure VSYNC option is set to AUTO in VIDEO settings then run the game until the issue is reproduced. When this happens, return to main menu.

2) Set VSYNC to OFF and run the game again for a few minutes, then go back to main menu. Normally, audio issue should not happen with VSYNC being OFF since emulation is synced with audio hardware this time.

3) grab the log files from the root of your SD card or USB drive and upload them here.

[Former user]

Comment # 21 originally posted by ekeeke31 on 2012-03-12T22:33:07.000Z:

issue \#192 has been merged into this issue.

[Former user]

Comment # 22 originally posted by ekeeke31 on 2012-03-12T22:35:30.000Z:

[Former user]

Comment # 23 originally posted by superballena on 2012-06-29T00:45:39.000Z:

I've managed to reproduce the problem in version 1.6.0. by just leaving a game running for exactly 30 minutes... But then I left the test version for 50 minutes and the problem didn't happen!

I'll do some longer tests just in case, but it seems that eke couldn't reproduce this bug because it's already been fixed.

-ICEknight

[Former user]

Comment # 25 originally posted by ekeeke31 on 2012-06-29T06:31:55.000Z:

That doesn't necessarily mean i fixed it, because as already seen by previous people, the issue is very inconsistent and random, to say the least, and i personnally never reproduced it, even on 1.6.0. I just added an option to force vsync off in that test dol and that would be normal you don't get any issue when it's off since the sync is different then.

Anyway, even if you can't reproduce it with VSYNC set to AUTO as stated in comment 20 instructions, it's still interesting to know about the console timings in both sync methods, which sadly, nobody has been bothered to post yet...

[Former user]

Comment # 26 originally posted by superballena on 2012-06-30T02:11:00.000Z:

I think I've found what triggers the problem in the 1.6.0 version.

If you're using the default settings, the sound problem won't appear (at least in half an hour), but if you're using the NTSC filter (I was using "composite"), the sound will start to crackle after 30 minutes.

I'll try the test version later, but I think it doesn't show the problem even with the filter applied. Even if I can't hear any faults in the sound, shall I try both the "Vsync auto" and the "Vsync off" modes for half an hour each, then close the emulator for the log to be saved properly?

-ICEknight

[Former user]

Comment # 27 originally posted by superballena on 2012-06-30T03:15:41.000Z:

Here's the logs I got in the SD card, after all the tests. I guess I should do "50Hz, No Vsync" next?

-ICEknight

[Former user]

Comment # 28 originally posted by superballena on 2012-06-30T03:37:47.000Z:

Note: I didn't get the sound problem in the test version, using those video combinations.

[Former user]

Comment # 29 originally posted by superballena on 2012-06-30T04:05:23.000Z:

So here's the log for "50Hz, no vsync".

For the record, Rolling Thunder 2 is possibly one of the best games for testing the audio and video syncronization errors.

The caracter select screen shows some blinking stuff that makes it very easy to catch any missing frames, and then the sound test can play every song in the game one after another (great for some variety while doing 30+ minute tests), and it's pretty easy to notice any anomalies that might occur in the instruments used.

[Former user]

Comment # 30 originally posted by superballena on 2012-06-30T04:05:58.000Z:

Oh, and no sound problems in this last test, either.

-ICEknight

[Former user]

Comment # 31 originally posted by ekeeke31 on 2012-06-30T08:20:53.000Z:

Thanks. I do not see anything different than i already measured though. Well, i guess i will leave this open for now and wait for feedback once the next version is released...

[Former user]

Comment # 32 originally posted by dizineUk on 2012-07-03T15:28:01.000Z:

I'm not sure if there should be any sound glitches but I could reproduce one on latest 1.70 genesis plus and loading virtua racing. I am not too familiar with the game and how it should run but if I just let it play the demo on title screen there is a point I believe after about 30sec to 1-2 mins where you kinda feel the emulation skips or slips up. The sound kinda buckles but not for more than a few seconds and its sort of like it crashes into itself.. then recovers. Happens in the same point each time so this maybe helps, maybe normal or maybe just my problem (I hope not).

I'm using 1.7.0 version. I have a pal wii on component cables, settings in genesis plus on auto, vsync auto. I'm using the NTSC roms. I load using "Bios" and I have bios.md TMSS inside bios directory if this matters or is correct.

(Don't know if its related but only problem apart from the above, I have noticeable tearing or corruption underneath my sonic sprite in sonic 2. I see it on the first stages straight away. The graphic distorts in horizontal bars and its striking. I will test this more and create another issue but I wondered whether the pal wii running NTSC had a problem, never noticed it look bad before on 1.60.)

[Former user]

Comment # 33 originally posted by ekeeke31 on 2012-07-03T15:54:23.000Z:

You mean the bridge part ? It's more related to the fact that virtua racing needs lot of CPU power to be emulated and this would be the result of skipped frame. Although, this demo mode is my "benchmark" which i check before each release to ensure i did not made unoptimized changes and i remember it was working fine with no sound skip. Maybe you are using NTSC filter in which case it is expected, as those are the 2 slowest things in this emulator. I cannot repeat issue with sonic 2, are you sure you are not using a filter. If you post your issue, don't forget to indicate what system, video and audio settings you are using.

[Former user]

Comment # 34 originally posted by superballena on 2012-07-03T17:15:42.000Z:

Uh oh... Just got the latest stable release and I'm getting the sound bug after 5 exact minutes, with the NTSC filter enabled.

I'm testing without filters as of right now.

[Former user]

Comment # 35 originally posted by dizineUk on 2012-07-03T17:34:17.000Z:

Right sorry I didn't provide more info previously... Genesis Plus 1.7.0 Its set to video progressive 60Hz, VSYNC Auto, Most system settings are on Auto those like PAL/NTSC,etc. I have all filters turned off and all other settings on defaults. I load off the SD card and have all the bios files in the folder and set to use bios only when loading. Interesting to hear that the NTSC filter is processor heavy because I was interested in it and had been checking the different settings with sonic etc. I'll check this again making sure the NTSC filter is off. The sonic thing is weird but in system settings I'm stuck with the hot swapping option enabled, I cannot switch it off for some reason, maybe this is the problem.

But yeah yesterday after I updated the sound thing was evident and I thought best to mention this. Thank you for such a quality emulator though, really appreciate the attention shown to the details and I hope I can help somehow where I can.

[Former user]

Comment # 36 originally posted by dizineUk on 2012-07-03T17:35:29.000Z:

Forgot the audio settings were the defaults, on high quality and I changed nothing in the options.

[Former user]

Comment # 37 originally posted by ekeeke31 on 2012-07-03T20:07:57.000Z:

There is indeed a bug with cart hot-swapping option, where it get stuck to ON once touched. However it shouldn't have any effect, only that you can't see if it is disabled or enabled but it's still switching when you hit the button.

[Former user]

Comment # 38 originally posted by superballena on 2012-07-03T22:03:43.000Z:

Okay, so with the default settings and no filters applied, the sound bug has appeared after leaving a game (specifically Rolling Thunder 2's sound test) running, at 13:20 and 23:40, in three consecutive tests.

Hope it helps.

[Former user]

Comment # 39 originally posted by superballena on 2012-07-03T22:13:50.000Z:

Oh, and the next time the desynchronization happens is at 33:50.

[Former user]

Comment # 40 originally posted by ekeeke31 on 2012-07-04T06:29:47.000Z:

Seems to be quite regular, i will try to reproduce it thanks. In the mean time, could you test again with the test dol posted in that thread and post timing results ?

[Former user]

Comment # 41 originally posted by superballena on 2012-07-04T08:21:35.000Z:

Sure, which settings do you want me to check this time?

[Former user]

Comment # 42 originally posted by ekeeke31 on 2012-07-04T08:53:36.000Z:

Just the same default settings with which you reproduced the issue in that game, first with VSYNC in AUTO (default) until it first happen at 13:20 then with VSYNC OFF for approx. the same amount of time.

[Former user]

Comment # 43 originally posted by ekeeke31 on 2012-07-04T13:38:21.000Z:

@ dizineUK: try reducing the value of SVP cycles in system settings and see if that helps The issue with sound is definitively not the same as the ones described here and are caused by emulation slowdown (i've experimented this before while beta testing "optimizations": emulator takes too much time to update one frame, including sound frame and this causes the audio hardware to reuse the previous frame when it's over, hence garbled audio). I'm pretty sure i tested the US version with default SVP cycle value (800 i think) just before the release and the whole title screen demo played without any skipping.

[Former user]

Comment # 44 originally posted by superballena on 2012-07-04T13:45:48.000Z:

Now that I think of it... The long tests I run on the test version posted in this thread came up with no errors regardless of the filter settings, so it might be something that was changed between that version and the latest release.

Or did you mean trying a new test dol posted somewhere else?

[Former user]

Comment # 45 originally posted by ekeeke31 on 2012-07-04T14:15:21.000Z:

As far as i remember, nothing was changed regarding audio since the last test dol i uploaded here. If you really can't reproduce it in that game using this test dol while it is consistent with last version, i might post another test dol based on current version with logged timings enabled (it's just an option to activate in the Makefile).

[Former user]

Comment # 46 originally posted by superballena on 2012-07-04T14:25:32.000Z:

Ok, I'll try it again just in case when I get home and let you know.

[Former user]

Comment # 47 originally posted by dizineUk on 2012-07-04T15:50:50.000Z:

@ ekeeke31 I'll try reducing the SVP cycles value, this is the first time I've ever noticed anything wrong.

I can't be sure there is a problem I just feel like something isn't quite right (sonic2 horizontal tearing thing?) but maybe I should try the test dol based on this version too.

[Former user]

Comment # 48 originally posted by superballena on 2012-07-04T18:32:10.000Z:

So I've tried the test version with the default settings and, again, no sound bugs whatsoever (I left it for 15 minutes this time).

The latest release keeps showing the problem at around 2:40, 13:20, 23:35 and 33:50 (default settings, as well).

[Former user]

Comment # 49 originally posted by ekeeke31 on 2012-07-04T19:41:51.000Z:

Damn, that's weird, I don't have the exact code on which this was based anymore but I am pretty sure there wasn't any difference in regard to audio sync. Only difference I think it was compiled with an older version of libogc/devkitPPC. Please try this test dol then, it's based on current version and should logs timings to the root directory.

One question though: are you by any chance using a background ogg music with the emulator ?

@ dizineUk: i cannot reproduce your tearing issue with sonic 2 but i can't output progressive video anyway and it looks like a filtering issue for me though I can't really visualize what you are exactly experimenting so unless you could make a video capture, there is nothing I can do. What am i sure though is that both issues have nothing to do with the one described in this section.

[Former user]

Comment # 50 originally posted by ekeeke31 on 2012-07-04T20:32:17.000Z:

@ dizineUk: i reproduced the issue you were having with Virtua Racing, it indeed has garbled audio for a few sec if I use INTERLACED video mode instead of ORIGINAL. It's probably because the minimal framerate in this mode is higher than in original mode (59.94 fps instead of 59.82 because interval between VSYNC is shorter) so if the emulation speed is very near that limit (which is the case in that part of the game), it might indeed skip a few frame and the result is always garbled audio since audio hardware is still running and requesting new samples at the exact same frequency...

Only solutions are to optimize the emulator or to decrease the number of SVP cycles executed per frame (800->700 for example). You could also try with VSYNC disabled but i doubt it will change much since the framerate in that case is still high (59.92 fps).

[Former user]

Comment # 51 originally posted by ekeeke31 on 2012-07-04T20:46:37.000Z:

Another possibility: VSYNC disabled + Master Clock forced to PAL, required framerate becomes 59.38 fps (that's actually the exact framerate of a PAL Mega Drive switched to "60hz")

[Former user]

Comment # 52 originally posted by superballena on 2012-07-04T23:12:12.000Z:

Not only I wasn't using any OGG background music, but I didn't know such a thing was possible until now...

The tests I run were made right after the emu showed a message of the default settings being reset (please check the PM regarding this at Spritesmind), and the only thing I did change was the ROM device from SD to USB.

I'll make sure to run some tests tomorrow and post them here.

[Former user]

Comment # 53 originally posted by superballena on 2012-07-05T16:00:21.000Z:

Here's the logs from the new version. Surprisingly, I didn't notice any audio problems in 50Hz mode.

[Former user]

Comment # 54 originally posted by ekeeke31 on 2012-07-05T19:48:15.000Z:

There is something weird in the ntsc log with VSYNC disabled: it seems like the interval between audio hardware interrupts is sometime zero, which is not normal. This could explain the garbled audio when VSYNC is enabled since the emulation is not synced with audio interrupts in that case and if that's still happen, well everything got desynced... this does not happen in the PAL logs.

[Former user]

Comment # 55 originally posted by dizineUk on 2012-07-06T01:31:01.000Z:

I just wondered about what you mentioned re: the interlaced video mode... because I use component cable and progressive that means video mode is interlaced? (please excuse me as I don't have my wii near me now)

I have settings on progressive, and output original or original (16:9), never ever interlaced. My Wii is PAL and all the Roms are NTSC, so the ntsc log would only prove something is not working correctly on NTSC wii's? Or could PAL wii loading NTSC roms be effected?

Hopefully I'll figure this out but thanks for your help and advice and explanation. I appreciate it.

[Former user]

Comment # 56 originally posted by ekeeke31 on 2012-07-06T08:17:11.000Z:

No, it's just that timings used are the same in interlaced (480i/576i) and progressive (480p) modes. That'said, you could run the test dol with VSYNC set to AUTO in progressive mode and upload your logs so i confirm it.

NTSC/PAL log is related to the emulated console TV mode: if VDP mode is set to AUTO, NTSC roms will run with NTSC timings, even on a PAL wii. Wii TV mode must be set to AUTO so that Wii is configured to PAL60 and VSYNC is enabled (if emulated TV mode and Wii TV mode differs, VSYNC is always disabled when set to AUTO).

[Former user]

Comment # 57 originally posted by ekeeke31 on 2012-07-08T20:05:15.000Z:

issue \#233 has been merged into this issue.

[Former user]

Comment # 58 originally posted by swsparklewind611 on 2012-07-30T18:16:29.000Z:

Sonic the Hedgehog 2 (MD/Genesis) has random audio crackling here. It seems to happen the most in the special stages. The issue does not seem to exist in 1.6.0. I have tried both versions on two different SD cards. No settings seem to change anything regarding this issue.

[Former user]

Comment # 59 originally posted by ekeeke31 on 2012-07-30T18:23:08.000Z:

Try with vsync off, interlaced mode, hq fm disabled. These are the only settings that could eventually change behavior. Anyway, i cannot reproduce your issue, as usual.

[Former user]

Comment # 60 originally posted by swsparklewind611 on 2012-07-30T19:01:57.000Z:

Strange, I thought I had tried everything. Here's what I've seen just now:

Vsync off, interlaced mode, hq fm disabled: No issues Vsync off, interlaced mode, hq fm enabled: No issues Vsync off, progressive mode, hq fm enabled: No issues Vsync on, progressive mode, hq fm enabled: Crackling sound issue

I guess I could keep Vsync off since it's not as bad as it can be with other programs. The video is not as smooth as it is with Vsync turned on, but at least turning Vsync off here doesn't cause the kind of tearing you sometimes see with PC games. I'd still prefer it if this could get fixed somehow though.

Did anything outside of Genesis Plus GX change that could affect this? Does 1.7.0 use a newer version of libogc? Could IOS/CIOS versions affect anything? Are there any differences in the Wii's audio hardware between different models?

[Former user]

Comment # 61 originally posted by ekeeke31 on 2012-07-30T19:23:02.000Z:

I really doubt you can notice a smooth difference by turning Vsync OFF, it's more a placebo effect or something because you know what VSYNC is supposed to do on PC emulators. The only thing you could eventually notice is a single frameskip after some period of time (like many seconds) but again, it would only be noticeable in a few games that would for example scroll the screen by one pixel on each frame and if your eyes are trained enough to detect 16.7ms transitions ;-)

It has NOTHING to do with libogc, IOS or any other crap like that. It's definitively related to the sync method I am using, which is used to get perfect sync with video AND audio hardware, hence why it works fine when VSYNC is disabled (in this case, only audio sync is done). Most emulators don't take care of this because it's very difficult to achieve and requires using exact timing of the host hardware (video AND audio rates), any subtle variations causing the desync you are experimenting.

I am actually trying to change the way sound chips are synchronized together at the end of emulated frames (which changed from 1.6.0) since it could also cause some deviation in the number of samples rendered on each frame and lead to possible desync with the audio hardware when vsync is used. We will see if it works better for sensitive Wii like yours (again, the problem is also that I cannot reproduce any of these issues, even when leaving games playing for hours with vsync on).

[Former user]

Comment # 62 originally posted by ekeeke31 on 2012-08-06T19:17:42.000Z:

issue \#269 has been merged into this issue.

[Former user]

Comment # 63 originally posted by swsparklewind611 on 2012-08-06T21:20:49.000Z:

If everything goes as expected, I'll be recording the Wii's audio directly through the line-in port on my PC, which should result in audio files with quite good quality. It'll take at least a couple of days though as I have to obtain the cables first.

[Former user]

Comment # 64 originally posted by swsparklewind611 on 2012-08-10T10:29:04.000Z:

Here's Sonic 2. I recorded all the way through the first two stages, both acts. First special stage begins at 02:00. Second special stage begins at 07:20.

[Former user]

Comment # 65 originally posted by swsparklewind611 on 2012-08-10T10:37:21.000Z:

And here's Sonic 3. I recorded all the way through the first stage, both acts. The first chaos emerald special stage begins at 00:46. The second at 03:11.Third at 05:54.

The issue is more noticeable in Sonic 2 though. In both games there's some kind of "audio crackling".

[Former user]

Comment # 66 originally posted by iceknightmail on 2012-09-07T09:25:35.000Z:

Perhaps this could be caused by the PAL 60 mode running at a very slightly different speed than NTSC?

[Former user]

Comment # 67 originally posted by swsparklewind611 on 2012-09-07T12:11:55.000Z:

Perhaps. But then I wonder why it has to run in PAL 60 mode in the first place. I don't think there is any TV today that can't handle NTSC.

[Former user]

Comment # 68 originally posted by ekeeke31 on 2012-09-07T14:21:46.000Z:

It has nothing to do with what TV support or does not support: PAL Wii can only output PAL60, not NTSC and NTSC Wii only output NTSC, obviously. So there is no "choice", when using a 60 hz TV mode, you are bound to what mode the console support, not the TV.

Anyway, from the timings that were uploaded, there is no difference between PAL60 and NTSC, and report has been made by PAL wii owner when i also own one.

Now, i finally have noticed the issue in one game on my side and the issue is also consistent with sega Cd games that use PCM. It's also clear it is an audio syncing issue as it does not happen when vsync is forced off. I have completely rewritten the way sound chips are synced together which affect the number of samples output on each frame since i think the change i did between 1.6.0 and 1.7.0 was not so good. Also plan to increase the number of buffers (double-buffering might be a little too restrictive if the timing is not "exact" as it does not allow any miss). Still need to test if this fixes the one game where i noticed the issue. Does not fix PCM issue (in Lunar 2 for example) though. So next round will be rewriting the main emulation syncing method to allow synchronization with both video and audio in a non-blocking way. Let's hope it will solve all these issues for good.

[Former user]

Comment # 69 originally posted by ekeeke31 on 2012-09-07T14:29:53.000Z:

[Former user]

Comment # 70 originally posted by ekeeke31 on 2012-09-13T23:34:56.000Z:

Seems like I fixed it. The key was not only to improve synchronization between emulated sound chips using a common clock based resampling for FM and PSG chips (to get an unique number of samples per frame, accurately tied to input framerate and output samplerate) but also to adjust the output framerate value (a little lesser than 48000hz to take resampler approximations in account).

I now can sync frame emulation with BOTH video & audio hardware interrupts and it does not seem to miss or repeat any single frame anymore, neither video frame (tested with Sonic 2 interlaced mode to verify field rendering is perfectly synchronized to Video Interrupt) or audio frame (tested with Lunar 2 intro and Virtua Racing to verify audio buffer under-run or overrun issues does not happen anymore).

[Former user]

Comment # 71 originally posted by ekeeke31 on 2012-09-13T23:49:50.000Z:

issue \#260 has been merged into this issue.

[Former user]

Comment # 72 originally posted by blackstockc on 2012-09-14T02:21:53.000Z:

Great news! Thanks for all of your hard work!

Sorry for an unrelated question, but could someone explain how to install these sub-versions? I do not see them in the downloads section.

Thanks!

[Former user]

Comment # 73 originally posted by ekeeke31 on 2012-09-14T07:02:33.000Z:

You will need to compile them yourself from SVN or find someone to compile it for you. As for recent updates, they were not committed to SVN and therefore not available yet.

[Former user]

Comment # 74 originally posted by swsparklewind611 on 2012-09-15T20:35:04.000Z:

If you could post a binary with your current fixes I would be glad to test it on my Wii and see if I find any issues.

[Former user]

Comment # 75 originally posted by ekeeke31 on 2012-09-18T20:06:16.000Z:

Here is a testing version based on my current work version (more or less).

Note that this is still beta so other bugs might exist (please report them here). It also has preliminary cue+bin with audio track support that you could eventually test more thoroughly than me (it was implemented a few days ago on my spare time and only quickly tested with two or three games I had in this format). The only current restriction is that .bin and .cue files must be named the same.

[Former user]

Comment # 76 originally posted by blackstockc on 2012-09-18T20:50:45.000Z:

Thanks! I will give it a shot.

[Former user]

Comment # 77 originally posted by swsparklewind611 on 2012-09-18T22:10:52.000Z:

Great work. It's looking really good so far. I just did some quick testing with Sonic 2 and Sonic 3 in the test version, and I could not hear any audio crackling anywhere. Not even in special stages. I will test Sonic CD later. Are there any other specific "possibly problematic" games that I should test?

[Former user]

Comment # 78 originally posted by blackstockc on 2012-09-19T13:38:09.000Z:

Audio is perfect for Lunar 1 (J). Still getting just a little crunch in the intro music for Lunar 2 (J).

[Former user]

Comment # 79 originally posted by TheRealBurntLasagna on 2012-09-19T13:49:38.000Z:

Thank you Ekeeke! I can re-confirm that Lunar II's opening audio is still a little crackly. I'm running off a USB HDD with 1.0 BIOS. Audio track support seems to work good with games such as Final Fight CD but is almost guaranteed to mess up with long cutscenes that use audio tracks, such as the opening to Snatcher and Popfulmail.

I haven't tested that many games with this build yet so I may post again later with a more broader examination . Hope this report helps and thanks again!

[Former user]

Comment # 80 originally posted by swsparklewind611 on 2012-09-19T14:46:53.000Z:

I just located an image of Lunar 2 (NTSC-J) and I can hear lots of audio crackling too. First in the opening (before the "new game" screen shows up), and then when Heero and the flying thing are digging in the wall and then falling down and it continues through the whole scene. I should probably note though that my image might not be ideal. It's iso+cue+wav. I will try with a bin+cue image if I find one. I'm testing this on a microSD card.

[Former user]

Comment # 81 originally posted by ekeeke31 on 2012-09-19T14:48:59.000Z:

That's unfortunate because i don't have any cracklings in lunar 2 intro anymore myself. And snatcher is the one i tested for audio track support , worked perfect during the whole intro :-/ Does it happen for anyone here ?

Please post recordings with reference to when crackling occurs so that i can check out and compare with what i got because i'm afraid at this point i'm out of ideas. Testing more games won't really help as it won't provide any usable proof or hint. Would be more useful if you could confirm same issues does not happen with VSYNC forced OFF or try in various video modes (original/interlaced, 50/60hz)

Also, try from SD or another USB drive and see if it is the same, maybe it struggles because accessing the device is too slow. In that case there is nothing i can do on my side.

[Former user]

Comment # 82 originally posted by ekeeke31 on 2012-09-19T14:55:33.000Z:

Image type makes no difference, what is important is game region (PAL/NTSC), system region (AUTO or forced), video mode (ORIGINAL/INTERLACED, 50/60HZ) and syncing method (VSYNC AUTO or OFF).

[Former user]

Comment # 83 originally posted by blackstockc on 2012-09-19T15:09:46.000Z:

Here is a sample of the Lunar 2 intro music. There is a faint rhythmic cracking sound in the background.

This occurs regardless of the game region, system region, video mode, and syncing method. This iso is on an SDHC card.

[Former user]

Comment # 84 originally posted by swsparklewind611 on 2012-09-19T15:28:21.000Z:

I did the same testing with my PSP's memory stick connected to the Wii through USB and I got much better results. I suggest adding a note about reading speed on the front page and/or the FAQ since it seems that as long as the storage medium or device is fast enough there is no audio crackling (at least not in this game so far).

A little off-topic, but do you know any good HDDs that would be reliable and fast enough for this? I've been looking around on wikis and reading people's experiences but it seems to be kind of hit-and-miss so far. The memory stick works great, but it only has 32 GB of space.

Anyway, awesome work. I will test some more. I still haven't tested Snatcher.

[Former user]

Comment # 85 originally posted by TheRealBurntLasagna on 2012-09-19T16:11:22.000Z:

I tested Lunar II again on my 4gb sandisk class 4 SD card and the audio didn't appear to crackle. I'm a little confused on why this is because my external HDD has never once had speed issues with anything else Wii related. This includes running Wii and GC games from it along with Turbografx-CD games with Wii-mednafen.

I understand that the CD is being read heavily during this section of the game (which is indicated by the Wii's LED) which makes me think it's an issue with the access rate on my HDD being slower than a flash SD card (which is normal).

However I still don't quite get why my HDD isn't capable of streaming something that was originally intended for an old CD-ROM drive? As stated its been able to do much more demanding things without issues.

[Former user]

Comment # 86 originally posted by ekeeke31 on 2012-09-19T17:28:58.000Z:

You cannot just simply compare CD drive 1x speed and USB speed when emulation is involved. I am emulating CD access at 1/75 s like a real 1X CD drive but during this time, I need to read a 2048 (DATA) or 2352 (CDDA) bytes sector from the device but also emulate for the same relative duration the whole Genesis hardware, SCD hardware, etc... while the only thing your old CD drive was doing was to transfer data to other hardware running in parrallel.

I am using a western digital 250gb passport hdd and have no speed issues. Like you figured, these parts are constantly streaming data from the device, which might not be the case in other programs. Or it could be that sega cd emulation is more taxing than these programs and gives less remaining time for file reading. Image file access could maybe be buffered in the emulator but i think it's already done by libfat (read ahead cache) and that it won't neccessarily improve anything as it would still need to access the device at enough speed. Also, even if it seems trivial, you might want to verify HBC or whatever you use to load the emulator is using ios58. The emulator does not try to reload it on startup like others might do and HDD cannot use USB2 mode if ios58 is not loaded.

[Former user]

Comment # 87 originally posted by nintygaming on 2012-09-19T17:53:19.000Z:

@ ekeeke31

I've tested 2 games thus far, Sonic CD and Lunar The Silver Star, and when I load a Save State of these CD games, the sound goes crazy. Other than that, everything seems fine. (using Bin+Cue format)

[Former user]

Comment # 88 originally posted by ekeeke31 on 2012-09-19T19:02:10.000Z:

hmm, i indeed forgot to seek to the saved audio track position when loading state. thanks for the report

[Former user]

Comment # 89 originally posted by swsparklewind611 on 2012-09-20T14:14:52.000Z:

I haven't located a copy of Snatcher yet, but I've seen a GUI bug in Genesis Plus GX. If you open the audio settings menu and try to change what kind of filtering to use, the entire filter option will often disappear and can't be accessed until you reopen the audio settings menu.

[Former user]

Comment # 90 originally posted by swsparklewind611 on 2012-09-20T14:17:03.000Z:

Thanks for telling us about your HDD. It seems that a lot of newer passport HDDs from Western Digital have non-removable software though, so I'm unsure how safe it would be for me to go with that.

[Former user]

Comment # 91 originally posted by dajur1 on 2012-09-25T19:50:49.000Z:

I just tried this on Sonic CD, Snatcher and Lunar 1 and I just get a loud static throughout. I can still hear the sound effects.

[Former user]

Comment # 92 originally posted by ekeeke31 on 2012-09-25T20:05:22.000Z:

You need a valid cue file with your bin file, with the exact same name and in the same directory or it won't work. For example, "Sonic CD.bin" needs a valid "Sonic CD.cue" file. If the cue file is invalid or is not found, the emulator will not be able to find audio tracks location in the bin file and the uploaded version will indeed output random data instead of music. I think the same happen if you load a simple iso file, i know I fixed this but am not sure if it was before uploading this beta or after.

So, bin/cue only if you wanna test audio track support. If it still doest not work, upload the cue so i could have a look ...

[Former user]

Comment # 93 originally posted by dajur1 on 2012-09-25T20:29:01.000Z:

The bin/cue files are named the same.

[Former user]

Comment # 94 originally posted by dajur1 on 2012-09-25T20:30:11.000Z:

Here is the .cue

[Former user]

Comment # 95 originally posted by ekeeke31 on 2012-09-25T20:40:03.000Z:

FILE "Lunar The Silver Star.bin" BINARY TRACK 01 MODE1/2352 INDEX 01 00:00:00

Not sure who made this crap but it only shows the first track and is obviously missing audio tracks indexes, making it completely useless. Sorry but it´s not a valid cue file, check redump.org for valid ones

[Former user]

Comment # 96 originally posted by swsparklewind611 on 2012-09-26T19:56:25.000Z:

@ daj: If all of your images are like this you should probably find a better source to download from, or find a better dumping method (if you're making images from physical CDs).

[Former user]

Comment # 97 originally posted by swsparklewind611 on 2012-09-26T21:24:35.000Z:

Speaking of redump.org: They list multiple bin files in many of their cue sheets. Is this supported in Genesis Plus GX? Sorry for going off-topic again.

[Former user]

Comment # 98 originally posted by ekeeke31 on 2012-09-27T06:27:38.000Z:

I have looked into it and they are indeed listing audio tracks as separated BIN files. Not sure why they did that but it's just RAW audio data extracted from the initial RAW bin image file. I guess there is as many dump format as there are dumping groups and each one feels like reinventing the wheel everytime ;-) Anyway, this should end up supported since it's valid cue file format but these cue files must obvioudly be used only with compatible dumps,it won't work for example to replace bad cue files like previous user had. It shouldn't be hard to find valid cue file elsewhere though.

[Former user]

Comment # 99 originally posted by iceknightmail on 2012-09-29T23:40:02.000Z:

Awesome! I've tried leaving the Rolling Thunder 2 sound test for 40 minutes with the same settings I've been using for my previous tests, and there seem to be no sound issues anymore, thanks a lot for your hard work. :)

Now, regarding CD audio:

-Most of the times I'm getting odd sound issues in the Earthworm Jim SE (USA BIOS 1.10) title screen (and sometimes in some of the company logos). -Not sure about this, but at least in EWJ SE it seems that the CD audio volume might be a bit too loud, or the rest of the audio is too low?

-Sometimes the game and sound will stop for a very brief time (happened to me during the "Down the tubes" demo in EWJ SE). -While playing Final Fight (USA BIOS 1.10), there was this time in the first level where, for a sligthly longer time than the previous issue, the game and sound seemed to freeze (with sound still playing) while the hard drive was reading something (probably the hard drive's fault, though). I shall look more into these two issues and report more specific info .

-Probably because of the CD unit's seek time not being emulated, the audio tracks seem to start playing too early, so the title screen animation in Sonic CD (Japan BIOS 1.00) is out of sync (the inial "SSSSSH-KAH" sound should finish right before the white flash, according to actual hardware running an original game). This lack of delay could be considered as an improvement when looping tracks in some games (less time without background music), so I'd leave it as a "CD seek time: Original/Fast" option in any case.

-There's some occasional sound crackling in the Snatcher (USA BIOS 1.10) intro, where the voice actor names appear. -Also, probably due to one of the previous two issues, the final segment of Snatcher's intro (with Jamie and Gillian talking to each other) is slightly out of sync, with the voices playing a split second before they should.

I'll be posting more details as I run further tests.

By the way, perhaps this issue should be renamed to a more general "Audio problems", since it's now covering the Mega-CD stuff?

[Former user]

Comment # 100 originally posted by iceknightmail on 2012-09-30T04:32:15.000Z:

Just tried Wonderdog and noticed that the CD sound volume doesn't change when it should fade out at the end of a level.

[Former user]

Comment # 101 originally posted by iceknightmail on 2012-09-30T04:41:06.000Z:

More Wonderdog: There's some sound crackling when playing track comment 4\.. It seems to happen whenever a music track has a certain part with a higher volume, in any game.

Also, I've just noticed that resetting the Mega-CD removes the disc from the system.

[Former user]

Comment # 102 originally posted by ekeeke31 on 2012-09-30T05:01:18.000Z:

Specific issues about audio track support will make more sense after i release an official version or commit my changes to svn. This was an earlier beta and i only expected report about it working or not will cue files, there is no need to look for issues yet as i am still modifying the code a lot.

As for your remarks: - i do not hear anything wrong with earthworm jim logo (it's weird on purpose i guess) and sfx are indeed at lower volume when cd audio is played in that game but either it's normal or is tied to cd fader not being emulated, resulting in cd audio volume being higger than expected.

-other issues might be related to specific cue files handling and pregap/postgap stuff. How much delay are we talking about ? If that's a few sec, there is no chances seek time is going to make so much differences, it's a few ms when the disc is spinning so you w-nouldn't hear anything. Anyway, upload your cue file so i can have a look.

-could not hear any issues with snatcher intro. If you are using hdd, try with a sdcard to see if it's better. As for the delay, no idea, either it's a problem with the cue file or something else.

- wonderdog: cd fader is not emulated (i think only kega emulates this actually) so that's normal

[Former user]

Comment # 103 originally posted by ekeeke31 on 2012-09-30T05:04:42.000Z:

comment 10\.1: reset button will eject the disc and ask you to press start button, i think that's normal bios behavior

[Former user]

Comment # 104 originally posted by iceknightmail on 2012-09-30T14:53:26.000Z:

My Japanese Mega-CD 1.00 doesn't eject the disc tray after reset. You have to go into the menu and eject it from there.

[Former user]

Comment # 105 originally posted by ekeeke31 on 2012-09-30T15:38:06.000Z:

The emulator does not open the tray / eject disc on Soft Reset with Japanese Mega-CD 1.00 BIOS either, not for me at least. It only does that with European 1.00 & USA 1.10 BIOS.

Anyway, I don't do anything special for Soft Reset on Mega CD side, the whole CD unit hardware is reseted like with Hard Reset, only RAM are left untouched, which is without a doubt the case with real hardware as well...

[Former user]

Comment # 106 originally posted by iceknightmail on 2012-09-30T17:59:00.000Z:

Oops, sorry, I should have double checked. Indeed that doesn't happen with the Japanese BIOS.

[Former user]

Comment # 107 originally posted by iceknightmail on 2012-10-01T00:34:50.000Z:

I've noticed that the CD sound problem I'm having only happens in the loudest parts of many CD tracks (like the words "Earthworm Jim" in the game's title)...

Perhaps it could be caused by my TV not being able to handle way-too-loud sounds? In that case, this might be automatically fixed once the volume fader is implemented.

[Former user]

Comment # 108 originally posted by nintygaming on 2012-10-01T00:44:49.000Z:

@ iceknigh

If your talking about the loud cracking sound that happens at random, then I can confirm that its not your TV speakers. I've tested it on multiple TV's and there's no difference. For example, the intro music for Sonic CD has a loud crackle/pop once the vocals kick in.

So ekeeke31, that's something you may want to look into when you get the time. (bin+cue here, and using SDHC class 4 card)

[Former user]

Comment # 109 originally posted by ekeeke31 on 2012-10-01T06:28:14.000Z:

Do not confuse things, it's not the same issue and not the same game. Loud crackle can happen if you have a bad image, i've seen a few of them having WAVE header embedded when they shouldn't, as if the bin file had been reconstructed.

Really, audio track emulation is damn simple, you read samples from the file and you resample them to the output stream at the output rate. Volume can only be affected by the fader, which is not emulated, but otherwise we read 16-bit samples and we output 16-bit samples, no magic trick here and nothing special i may want to look into... The words "earthworm jim" play fine for me, have you trying to play the associated track from CD player interface and see if it goes wrong ?

Anyway, as said before, this was a beta i posted and lot of things have been modified since so it would be better to post issues once it's released. I am more interested in errors caused by .cue files mishandling since there are a lot of different cases that must be handled. In short words, post your cue files if you have any problems.

[Former user]

Comment # 110 originally posted by swsparklewind611 on 2012-10-01T22:39:40.000Z:

Oh, I thought the beta was about audio crackling (since that was the reason why I requested it). Is there anything we could look for when it comes to issues with .cue files? How do we know that a .cue file is handled incorrectly? I haven't seen such issues so far, but I'm willing to test and see if I find anything.

[Former user]

Comment # 111 originally posted by ekeeke31 on 2012-10-01T22:46:37.000Z:

The beta is off course about initial audio crackling issue, which is now fixed but it also had preliminary CUE file support for audio CD tracks emulation from BIN files, so if someone has problems with audio tracks output, I'm interested to look at the CUE file to see if I didn't forgot some edge cases.

[Former user]

Comment # 112 originally posted by TheRealBurntLasagna on 2012-10-03T16:09:56.000Z:

Hello ekeeke, I have another question.

As you already know I've been having issues with my external HDD not being up to snuff for Sega CD emulation. This has been evident with Lunar II's opening still stuttering when using my USB HDD.

However, I've recently tried running just the data track of Lunar II (extracted using TurboRip) and the opening no longer stuttered! I'm interested on why this is? Since the current beta does not support ISO/WAV/CUE archives yet I can not test to see if this fixes the audio track stuttering as well.

Could this be happening because the BIN/CUE I'm using is messed up or is ISO/WAV/CUE archives a less demanding format? If it makes a difference I've been converting my rips to BIN/CUE by mounting them to a virtual drive and ripping them to BIN with ImgBurn.

Hoping you can help shed some lite on this issue and thank you for your time.

[Former user]

Comment # 113 originally posted by ekeeke31 on 2012-10-03T20:42:54.000Z:

I am not sure what you exactly mean by mounting your rips to rip them to BIN, I guess that means that you had ISO+MP3 images that you tried to convert to BIN+CUE this way ? This is not going to produce an accurate image sadly, better make an image from a real CD or get proper BIN/CUE images online. However, I don't think inaccurate rips could cause stuttering or emulation slowdown, the effect is generally more problems with audio tracks being misplayed.

ISO handling (or even BIN handling without having a CUE file) is indeed less demanding, not because of the format but because audio track processing obviously requires additional CPU to process the samples and additional device accesses to read them from image files.

However, since Mega CD can NOT access AUDIO and DATA from disc image at the same time and this part of Lunar 2 seems to be continuously accessing raw PCM DATA from disc, it is curious that you see any differences since AUDIO tracks are not being used there, from what I can tell.

The only difference between BIN and ISO is actually the size of Data track "sectors": in both case we need to read 2048 bytes of data per sector but while .iso format represents a "ripped" image of the Data track and stores these 2048 bytes sectors sequentially, .bin format stores full format CD blocks, which is 16-bytes header + 2048 bytes data + 288 bytes of error correction data (2352 bytes in total). So in the latter case you cannot read those sectors sequentially, you have to skip (using fseek) a few bytes in the image file every time a block of data is being read (75 times per second exactly). Depending on how your device like that, I guess it can be more or less efficiently handled.

Did you try to load the bin file without having any cue file (so that audio tracks are not processed) and see if it behaves differently from the iso ?

[Former user]

Comment # 114 originally posted by TheRealBurntLasagna on 2012-10-04T21:05:21.000Z:

Let me clear things up. I I'm ripping from my actual disk. However, I always rip my Sega CD games to ISO/WAV/CUE using TurboRip. If I need to convert them to BIN then I mount them to a virtual CD-ROM drive and convert them to BIN using ImgBurn. Is this an issue?

I have tried loading just the BIN without a CUE but it still has popping. Could ISO/WAV/CUE just be more optimal for my external HDD?

[Former user]

Comment # 115 originally posted by ekeeke31 on 2012-10-05T20:51:09.000Z:

like i explained, reading from BIN files require additional file seeking each time a block is accessed so yes it´s less optimal in theory, although i cannot notice any differences with my own setup...

as for your method to generate cue/bin, it might be less accurate than a straight cue/ bin rip using ImgBurn directly ( i still use good old cdrwin personally), depending how your program mounts iso/wav/cue but as said before, the only issues this could bring are audio track sync issues, for example if gaps are wrongly added or misplaced, nothing more. the fact the issue you are having with bin does not happen when using sdcard clearly shows it´s caused by slow device access, which is itself causing emulation slowdown and desync.

[Former user]

Comment # 116 originally posted by iceknightmail on 2012-10-13T14:09:23.000Z:

It seems that CUE files generated by CloneCD aren't supported due to the indexes not having a trailing '0'.

So this:
TRACK 2 AUDIO
INDEX 0 03:05:48
INDEX 1 03:07:48
...doesn't work.

But this:
TRACK 2 AUDIO
INDEX 00 03:05:48
INDEX 01 03:07:48
...does work.

Also, for some reason, the PAL Mega-CD rips I've created with CloneCD crash the emulator right after switching the screen to 50Hz, but they work perfectly if I force the VDP mode to NTSC.

I'm attaching the CUE of a self-ripped PAL game that only works after adding the 0's and forcing NTSC.

[Former user]

Comment # 117 originally posted by iceknightmail on 2012-10-13T14:17:25.000Z:

I've experienced the same problems I described previously in this game now that I've ripped it myself:

-Occasional split-second freezing with frozen sound, probably due to the hard drive's fault.
-Crackling sound when the volume might be hitting a peak in CD tracks (Track 4 at 00:42, 00:47, right between 00:50 and 00:51, and so on).
This happens in both the PAL and Japanese version, at the exact points in the music, no matter if the tracks are playing in-game or with the system's CD player, and they don't happen when being played in my PC.

[Former user]

Comment # 118 originally posted by iceknightmail on 2012-10-13T14:33:16.000Z:

Looks like switching these PAL rips to "Auto" or "PAL" video mode, after they've started running in NTSC, also makes the emulator crash after the screen switches to 50Hz.

No core dumps given, just the game/BIOS screen stays in place, with no sound and no way of doing a thing without turning the Wii off and on again.

[Former user]

Comment # 119 originally posted by ekeeke31 on 2012-10-13T15:16:08.000Z:

Ok, I quickly fixed support for unusual CUE commands format, I was right in the process of doing official release so it was just about time I guess :-)

I tried your cue with my modified code and a BIN dump I had (I guess .img is just a custom name for .bin files, right ?) and it worked fine in PAL mode, no crackling sound anywhere and no intermittent freezing so I don't know what to tell you. Again, I cannot do anything about issues I can not reproduce , same goes for HDD access slowdownx, mine work fine and I sadly cannot take in consideration every existing hardware inconsistencies or every tiny cracklings people hear, the real harwdare might have been far worst and more unstable when it came to audio but you know, people would probably never notice it because they were more focused on playing the game than tracking down sound bugs ;-)

That's said, there was A LOT of modifications/ rewrite since the beta I uploaded (CD fader was implemented for example) so I will say it again but it would be better to wait for next version before spending time to chase down specific bugs

[Former user]

Comment # 120 originally posted by iceknightmail on 2012-10-13T15:51:44.000Z:

Something tells me that the sound crackling will be gone in the version with the fader, so I'm not too worried about that.

Regarding the occasional random split-second freezing that happens when the emu fails to access the BIN file, I was wondering if it wouldn't be feasable for it to act as if the Mega-CD was just failing to read from the CD?

The only real concern I have right now is with the PAL Mega-CD games freezing, since now I can't test the sound synchronization with the rip of Snatcher I've just made. =\

[Former user]

Comment # 121 originally posted by ekeeke31 on 2012-10-13T16:20:52.000Z:

I would not worry about that, I think I remember there was a bug with PAL mode (not Mega CD specific) in the beta I posted, it was related to sound buffers being too low-dimensioned for PAL (less frames per seconds = more samples per frames) when I first implemented the new sound chip synchronization. It was shorty fixed after the initial upload.

[Former user]

Comment # 122 originally posted by ekeeke31 on 2012-10-13T17:05:28.000Z:

Should be fixed in r715

[Former user]

Comment # 123 originally posted by nintygaming on 2012-10-13T18:42:41.000Z:

There appears to be a new issue with the new release. When you hit the menu button, and then exit out of the menu, there's a graphical glitch that stays permanently on the bottom of the screen.

Other than that, everything seems fine. Save states work with CD games, audio tracks don't crackle and pop anymore, etc.

I'm sure that the graphical glitch is a minor fix that should be easy. I'll make an issue for it though just in case.

[Former user]

Comment # 124 originally posted by iceknightmail on 2012-10-13T19:48:11.000Z:

Indeed, there doesn't seem to be any sound crackling on CD tracks anymore, and PAL games work like a charm now. Here's what I've come across while testing this new build:

-Snatcher PAL: I've ripped and verified my own image, and the intro CD track seems to be playing a bit too early during Gillian and Jamie's conversation, the exact same thing happening with the US version image I already had. Perhaps the game took into account the initial track seek time for synchronization?
-Smurfs PAL: The CD fader seems not to be able to fade the sound gradually. This is noticeable in the intro with the stork (right after skipping the movie and selecting language).
-The same random split-second freezing seems to occur from time to time. I'll try using an SD card and report back.

[Former user]

Comment # 125 originally posted by iceknightmail on 2012-10-13T20:07:07.000Z:

Oh, hey, did something happen with the borders?

[Former user]

Comment # 126 originally posted by ekeeke31 on 2012-10-13T23:30:49.000Z:

See the other issue report and consider deleting your config.ini, the one being created by the beta is incompatible with official release and might corrupt some settings when being loaded.

As for your other issues, please consider making new and separate issue reports as this is not meant to be a discussion board and it's impossible for me to address all of them this way. I consider this specific issue to be closed and would expect these words to be my last ones here.

Note that i wouldn't consider tiny desync with audio tracks as a real issue as it's likely never perfect either on real harware. And i already emulate drive access time, which is most noticeable when tracks at the end of the disc are being accessed (spec says something about 1.5 s max access time so i made it related to the maximal number of sectors on a disc and the number of sectors to seek when a track is being played). However, it's impossible to really emulate this accurately because the damn thing is mechanical. For the same reason, it would have been very hard to keep software execution in sync with cd-da playback because it is very likely hardware dependent and varying as time passes. So, unless we are speaking of several sec of delay (which is more caused by missing or added pauses in cue or bin image files), i would not focus too much on that. And as far as i tested it, snatcher intro was perfectly fine for me and i didn't notice any real desync between the voices and acting, nothling obvioud at least.

I will have a look at fader implementation, i only tested it with Earthworm Jim (music volume is adjustable through option menu) but really it should work as specified in all cases, it's a very simple hardware to emulate, with no real edge cases, and the sound is supposed to be gradually faded in or out, from the current volume enveloppe to the value programmed in a single register.

[Former user]

Comment # 127 originally posted by ekeeke31 on 2013-05-22T08:05:42.000Z:

issue #260 has been merged into this issue.