Bar detection; main BPM loop detection

[mixxxbot]

Reported by: guillem-gilabert
Date: 2009-08-26T10:39:42Z
Status: Confirmed
Importance: Wishlist
Launchpad Issue: lp419155
Tags: beatgrid, bpm
Attachments: [Main BPM loop](https://bugs.launchpad.net/bugs/419155/+attachment/681839/+files/Main BPM loop), Suggestion, [measure mark patch](https://bugs.launchpad.net/bugs/419155/+attachment/1121253/+files/measure mark patch), [measure mark patch 2](https://bugs.launchpad.net/bugs/419155/+attachment/1121625/+files/measure mark patch 2), [measure mark patch #4912](https://bugs.launchpad.net/bugs/419155/+attachment/1125360/+files/measure mark patch #4912)

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It would be helpful that Mixxx detects the strong BPM of each 4 BPM (normally in a song there is always a 4 BPM loop, and on of this BPM shows the beggining of this loop).

I have attached a screenshot of Virtual Dj showing this feature.

Also it would be nice to have three buttons like Hercules MK2 has, one that allows to go to the next BPM, another that allows to go to the next 2 BPM, and the ohter to the next 3 BPM.

I think with this improvement it would be a lot easy to mix and more people will start using Mixxx in replacement of other comercial mix software.

[mixxxbot]

Commented by: guillem-gilabert
Date: 2009-08-26T10:39:42Z
Attachments: [Main BPM loop](https://bugs.launchpad.net/mixxx/+bug/419155/+attachment/681839/+files/Main BPM loop)

[mixxxbot]

Commented by: mik-gmx-deactivatedaccount
Date: 2010-01-22T12:05:21Z

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Also here is bug report I would appreciate such a feature, too. You mean the concept of beats, bars and phrases and emphasising every forth beat marker. It is a good visual mark and makes it much easier to decide if the mixed in track is ahead or behind.

[mixxxbot]

Commented by: guillem-gilabert
Date: 2010-01-25T10:31:29Z

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Yes, you descrived it better than me :)

I really hope this feature is soon implemented, and thanks for the correction ironstorm!

Indeed, this feature is the only one that pushes back my grilfriend to use Mixxx.

[mixxxbot]

Commented by: mik-gmx-deactivatedaccount
Date: 2010-01-27T19:03:47Z
Attachments: Suggestion

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I've modified ./src/waveform/waveformrenderbeat.cpp in a way that marks measures. (The file was taken from current stable release on mixxx.org)

[mixxxbot]

Commented by: Pegasus-RPG
Date: 2010-01-28T13:57:07Z

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Mik: can you please apply your changes to the latest trunk and attach a diff here?
Instructions for checking out trunk are here: http://mixxx.org/wiki/doku.php/using_bazaar#making_it_work_like_svn_aka_centralized_mode

[mixxxbot]

Commented by: mik-gmx-deactivatedaccount
Date: 2010-01-28T15:44:07Z

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I'll try my best. But likely it has to wait until tomorrow.

[mixxxbot]

Commented by: mik-gmx-deactivatedaccount
Date: 2010-01-29T10:08:37Z
Attachments: [measure mark patch](https://bugs.launchpad.net/mixxx/+bug/419155/+attachment/1121253/+files/measure mark patch)

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Here is the requested patch made to current trunk (today).

BTW: You couldn't wait to fix the height issue. Do you want to know what in my eyes is the problem? (Of course you want, as long as you didn't already know)

Your calculation for half height has a logic flaw

double halfHeight = m_iHeight/2; // not good, you forgot zero

Assume m_iHeight = 100 then halfHeight = 50. Now lets count pixels starting from -50..-1 counts 50 and 1..50 counts again 50 but where is zero? If you want to have zero you have to substract it.

double halfHeight = (m_iHeight-1)/2; // from bottom to top all pixels are here

[mixxxbot]

Commented by: mik-gmx-deactivatedaccount
Date: 2010-01-29T14:36:13Z

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Stop my patch is broken. I've messed us something with bazar

[mixxxbot]

Commented by: mik-gmx-deactivatedaccount
Date: 2010-01-29T16:37:57Z
Attachments: [measure mark patch 2](https://bugs.launchpad.net/mixxx/+bug/419155/+attachment/1121625/+files/measure mark patch 2)

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Now I have cleaned up all my mixxx builds and this time the patch is definitly working.

But on Ubuntu I've had problems with compiling. It missed a file called neaccdec.h from libavcodec, which isn't presend in Ubuntu. Thus I've switched m4a support off in scons. (m4a=0)

BTW: Library looks much better.

[mixxxbot]

Commented by: esbrandt
Date: 2010-01-29T21:37:37Z

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The short horizontal line is very subtile, if looking from some distance it is barely visible.
Since the mark on the 4th bar from your patch is a really useful guide it should be displayed bold imho.

[mixxxbot]

Commented by: mik-gmx-deactivatedaccount
Date: 2010-02-01T20:38:19Z
Attachments: [measure mark patch #4912](https://bugs.launchpad.net/mixxx/+bug/419155/+attachment/1125360/+files/measure mark patch #4912)

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Ok, then I've made a variant into patch #⁠3 onto revision 2296

Screenshot: http://img718.imageshack.us/i/mixxxmeasuremarks.png/

[mixxxbot]

Commented by: guillem-gilabert
Date: 2010-03-01T09:36:20Z

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Hi everyone!

Nice patch mik, and thank you so much for this usuefull feature.

However iIdownloaded now the last bazar code and I could not feend this feature.

Have you already pushed this change to the main code trunck so that in future stable verions of Mixxx we can enjoy this feature?

Thanks!

[mixxxbot]

Commented by: mik-gmx-deactivatedaccount
Date: 2010-03-01T16:31:35Z

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Hi!

Thanks for your feedback. Currently I'm not very busy on mixxxx because I'm
not very healthy for the next weeks, mabye months.

I think this feature makes much more sense if beat marks are adjustable. I
don't know of any plans to merge this stuff to the trunk unlike if I'm
finished with adjustable beat marks.

There's also a experimental feature called beatjuggling which maybe superseeds
current beat marks (https://code.launchpad.net/mixxx)

Sorry that I can't help you more. (Got to kill some doctors)

Am Montag, 1. März 2010 10:36:20 schrieb borgg:

Hi everyone!

Nice patch mik, and thank you so much for this usuefull feature.

However iIdownloaded now the last bazar code and I could not feend this
feature.

Have you already pushed this change to the main code trunck so that in
future stable verions of Mixxx we can enjoy this feature?

Thanks!

[mixxxbot]

Duplicate of #5852