Random swapping covers

[mixxxbot]

Reported by: daschuer
Date: 2016-07-27T21:57:53Z
Status: Fix Committed
Importance: Medium
Launchpad Issue: lp1607097

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I have two tracks which are randomly swapping covers.
It can happen that the Library row shows one cover and the Big cover art shows the other.
After restarting Mixxx it can be the other way round.

Reloading the cover from the file, does not change anything.

Tested with Mixxx 2.1-pre-alpha r5830

[mixxxbot]

Commented by: daschuer
Date: 2016-07-27T22:03:59Z

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Both cover have the same hash "166"
It looks a bit short, my maximum hash is "65478"

[mixxxbot]

Commented by: daschuer
Date: 2016-07-27T22:13:24Z

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http://doc.qt.io/qt-5/qbytearray.html#qChecksum

[mixxxbot]

Commented by: daschuer
Date: 2016-07-29T19:31:10Z

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I think that can be solved, by comparing the new cover, and the existing cover with the same 16 bit CRC byte by byte.
If they are not equal, we can add 0x10000 to the CRC. This way we can distinguish them later.

What do you think?

[mixxxbot]

Commented by: daschuer
Date: 2016-07-30T09:01:37Z

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Using the CRC as unique ID is a failure by design.
I think we should move to a location as unique ID. The CRC can be used to detect changed covers.

All files with the same embedded cover art will have the location of the first occurred track with this cover. If the CRC of the cover at the ID location changes, all other files have to invalidate this ID and fall back to its own location or an other track with the same cover.

We have to make sure that the case works flawlessly when a user exchanges the cover.jpg in a folder.

Any idea?

[mixxxbot]

Commented by: Be-ing
Date: 2017-11-11T16:11:55Z

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#996

[mixxxbot]

Commented by: Be-ing
Date: 2017-11-11T16:12:41Z

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Should this be fixed for 2.1 or postponed?

[mixxxbot]

Commented by: uklotzde
Date: 2017-11-11T21:09:09Z

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I would recommend to postpone it, because it is more or less an inconvenience and requires substantial changes. Maybe we can come up with a clever strategy how to detect and update existing database entries on the fly.

Cover art from the audio file will be imported together with the rest of the metadata. Since writing metadata back into files is still disabled, re-importing both from the external audio file is dangerous. But we can reload just the cover image, either automatically as required or by providing a new user action.

[mixxxbot]

Commented by: Be-ing
Date: 2017-11-11T22:10:44Z

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Okay, removing the 2.1 milestone then. If you or Daniel want to commit to fixing it for 2.2, go ahead and assign the bug to that milestone.

[mixxxbot]

Commented by: rryan
Date: 2018-09-20T18:40:23Z

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Due to lack of progress, marking Triaged and clearing assignee. Feel
free to revert if it is in fact still in progress :).

[mixxxbot]

Issue closed with status Fix Committed.