Quantize button cannot be enabled

[Daniel Schürmann]

.. when a track is freshly loaded and sync is enabled.
Once the track is played , quantize button works as usual. It works also if the track is paused again.

[Owen Williams (ywwg)]

Can't reproduce. I enable sync, load a track, click quantize, and it lights up as normal.

[Owen Williams (ywwg)]

Has anyone else seen this? If not I'd like to close the bug

[Daniel Schürmann (daschuer)]

I will retest it.

[Daniel Schürmann (daschuer)]

OK, I cannot exactly reproduce it, but if you load a not analyzed Track, the Quantization button flashes short, but remains off.
If you enable the quantization button before the track is loaded, Quantization is switched off.
If you disable SYNC, you can always switch Quantization.

I would prefer not to switch Quantization from inside Mixxx. This way you can have it enabled all the time regardless of the Sync state or if the track has a beatgrid or not.
If no beat grid is there Quantization just cannot work but the Request is still valid.

[RJ Skerry-Ryan (rryan)]

Hm, I agree -- switching it off will prevent "set and forget" operation.
Also loading a track that hasn't been analyzed yet will switch it off even
though the track will get a beatgrid after it is analyzed.

On Wed, Nov 19, 2014 at 5:04 PM, Daniel Schürmann <
<email address hidden>> wrote:

> OK, I cannot exactly reproduce it, but if you load a not analyzed Track,
> the Quantization button flashes short, but remains off.
> If you enable the quantization button before the track is loaded,
> Quantization is switched off.
> If you disable SYNC, you can always switch Quantization.
>
> I would prefer not to switch Quantization from inside Mixxx. This way you
> can have it enabled all the time regardless of the Sync state or if the
> track has a beatgrid or not.
> If no beat grid is there Quantization just cannot work but the Request is
> still valid.
>
> --
> You received this bug notification because you are a member of Mixxx
> Development Team, which is subscribed to Mixxx.
> https://bugs.launchpad.net/bugs/1321379
>
> Title:
> Quantize button cannot be enabled
>
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>

[jus (jus)]

Based on an earlier discussion for v1.10 (lp:898213), the reason for not turning Q on by default was sub-par beatgridding.

Things have improved since then, and "always on" Q would eliminate sources of error.
There have been numerous times i found the syncing "not working" because the tiny Q button was disabled.

[RJ Skerry-Ryan (rryan)]

Hm, always on might be nice now that we have better beatgrids. But I think that's different from this bug report? This report covers quantize turning off when the track does not have a beatgrid. I believe it's caused by this logic here:

https://github.com/mixxxdj/mixxx/blob/master/src/engine/bpmcontrol.cpp#L505

[Owen Williams (ywwg)]

I will have to do some testing if we move to a default-on quantize button. Quantize has a lot of implications now that the user may not want (all loops are quantized, seeking is quantized, etc). Also there was a bug fix recently so that just pushing sync will match BPM and phase without the need for quantize to be on. Please test with recent trunk and let me know what you think.

[RJ Skerry-Ryan (rryan)]

Ah, easy repro on current master:

1) Disable constant tempo assumption. Check re-analyze when settings change so the track gets a BeatMap.

2) Load a track (playhead will be before the first beat in my case unless playpos 0 has a beat)

3) Turn sync on for the deck.

4) Click quantize -- it disables itself instantly.

AutoDJ also constantly turns quantize off because of this with every transition.

[RJ Skerry-Ryan (rryan)]

I also think from a usability standpoint, if the user turns something on we shouldn't turn it off. We should treat it as a "do this when reasonably possible" and give feedback when the deck is unsyncable instead.

[Owen Williams (ywwg)]

realistically not getting to this right now. Also I don't have any beatmap tracks so it's hard for me to test

[Owen Williams (ywwg)]

This is pretty easy, and it even prints out an error:

"No beatgrid but sync and quantize enabled. Disabling quantize mode"

This is happening because with the beatmap is returning -1 for findPrevBeat at the start of the track. Beatmap should extrapolate from the first bpm back in time for arbitrary negative positions.

[Owen Williams (ywwg)]

this will cause big problems with master sync and beatmaps, so we should fix it

[Owen Williams (ywwg)]

I removed the bit that disables quantize. we still need to fix beatmaps in preroll

[Owen Williams (ywwg)]

This bug is fixed, I'll open a new one for preroll beatmaps

[Swiftb0y (swiftb0y)]

Mixxx now uses GitHub for bug tracking. This bug has been migrated to:
https://github.com/mixxxdj/mixxx/issues/7478