Bug 358542

Summary:	15.13.0 git master - Monitor audio levels aren't showing silent levels properly
Product:	[Applications] kdenlive	Reporter:	Unknown <null>
Component:	User Interface & Miscellaneous	Assignee:	Jean-Baptiste Mardelle <jb>
Status:	RESOLVED FIXED
Severity:	normal	CC:	null, wegwerf-1-2-3
Priority:	NOR
Version First Reported In:	unspecified
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	Silence example

Description Unknown 2016-01-25 16:45:59 UTC

I created a test .mp3 file with perfect silence on it through Audacity. Importing and playing back into Kdenlive 15.13.0, the silence reads at around -30db, which seems to be the bare minimum level that the indicators will stay... which isn't indicating true silence.

Normal operations should be silence not showing on the audio level meter at all.

(I'm including the test file for use).

Reproducible: Always




Tested using Kdenlive 15.13.0.r6959.f4e0fb5-1 on Antergos (Arch) Linux x64, GNOME 3.18.2

Comment 1 Unknown 2016-01-25 16:46:28 UTC

Created attachment 96834 [details]
Silence example

Comment 2 Wegwerf 2016-01-25 17:47:59 UTC

Noticed that too, so that I also included it independently in bug https://bugs.kde.org/show_bug.cgi?id=358427. However, I also still have some issues with the exact marks, as I miss the common -10dB mark. For me, it seems that "silence" is stuck around -22dB or so.

Comment 3 Jean-Baptiste Mardelle 2016-01-25 18:53:18 UTC

Yes, there currently is a problem with low audio levels. I tracked the issue to MLT's audiolevel filter that we use and proposed a patch here: https://github.com/mltframework/mlt/pull/95

With the patch, it works perfectly for me.

Comment 4 Unknown 2016-01-25 22:27:39 UTC

Good stuff. Will wait for the patch to hopefully be implemented by MLT dev's.

Thanks JB!

Comment 5 Unknown 2016-01-25 22:43:18 UTC

Just curious, how can we check if/when the MLT crew has implemented this patch?

Comment 6 Jean-Baptiste Mardelle 2016-01-25 23:03:46 UTC

I will try to remember closing this bug if the patch is committed to MLT, but otherwise you can check the github link in my previous comment where the discussion about the patch is happening. The status of the issue will be changed from "open" to "closed" if it is accepted. Dan Dennedy, maintainer of MLT is usually quite reactive.

Comment 7 Unknown 2016-01-25 23:10:51 UTC

Awesome. Thanks for the intel'.

Comment 8 Jean-Baptiste Mardelle 2016-01-26 07:26:40 UTC

LasT part of this bug was fixed in MLT git master, should work fine now

Comment 9 Unknown 2016-01-26 17:42:05 UTC

Confirmed (in Arch). Building and installing mlt-git package, then building and installing kdenlive-git package shows this issue has been resolved. Thanks guys!

Marking this bug as fixed.