Bug 68 – Vertical scale only has zeros when displaying Waveform (dB) view at -48 dB

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Audacity 3.0.3 development began 19th April 2021

Audacity Bugzilla

Bug 68 - Vertical scale only has zeros when displaying Waveform (dB) view at -48 dB


Summary:	Vertical scale only has zeros when displaying Waveform (dB) view at -48 dB

Status:	RESOLVED FIXED

Product:	Audacity
Classification:	Unclassified
Component:	Application Core
Version:	2.2.0
Hardware:	Per OS All

Importance:	P4 Repeatable
Assigned To:	Default Assignee for New Bugs

URL:
Keywords:	test_single_OS

Duplicates:	1015 (view as bug list)
Depends on:
Blocks:
	Show dependency tree / graph

Reported:	2010-01-28 15:12 UTC by James Crook
Modified:	2018-08-20 11:45 UTC (History)
CC List:	2 users (show)

See Also:
Steps To Reproduce:	1. Launch Audacity, set Meter dB Range in Interface Preferences to -48 dB. 2. Record a few seconds of mono or stereo audio, Stop. 3. Change to Waveform (dB) view if Default View Mode in Preferences not already set to it. 4 Only figures on the vertical scale are "0" and "0" 5. Drag track down to see the real figures Also happens with imports or generated audio. Other waveform/meter dB ranges show the correct minimum dB on the vertical scale.
Release Note:
First Git SHA:
Group:	---
Workaround:
Closed:	2018-08-20 00:00:00

Flags:	james.k.crook: Test‑OK‑Win+

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Description James Crook 2010-01-28 15:12:01 UTC

Comment 1 James Crook 2017-05-14 18:08:50 UTC

Don't know when the fix was made, but now a -60 level is shown too.

Comment 2 Gale Andrews 2017-05-29 13:24:37 UTC

*** STEPS CHANGED ***  and reopened.

Fully reproducible, but now only with -48 dB range.

Comment 3 James Crook 2017-05-29 17:52:40 UTC

DEVEL - FIX MADE
https://github.com/audacity/audacity/commit/545dbaf1cd17cc835267c429e17aa8787557d554

The fix is in logic that is to avoid showing 0.0 as -0.0 in the case of small rounding errors.  If my fix is wrong, the most likely consequence is that we will see -0.0 or -0.somesmallvalue in some place where we want 0.0.  Since my fix only acts on log scales, a mistake in my fix is most unlikely to affect rulers used for linear scales such as mixers.

I tested at -36 dB and -48 dB and -60 dB.

Note that tracks that have very little height may show only one number.  That's OK.

Comment 4 James Crook 2017-05-29 18:01:17 UTC

Umm.  Actually Comment #3 has an incorrect statement.  The ruler IS a linear scale, in a certain sense, and is like the mixer and meter rulers, which also are in dB, so we could in theory see a -0.0 on those scales.  However I have looked and haven't seen that, even with some resizing to try to provoke that.

Comment 5 Gale Andrews 2017-06-02 01:43:22 UTC

(In reply to James Crook from comment #4)
Thanks James, I did not find a problem on Win 10, even in Meter Toolbar or Mixer Board, or Linux netbook (in case the small form factor there affected anything). I tried all the Meter dB ranges on Win 10.

Comment 6 James Crook 2017-08-16 06:34:24 UTC

*** Bug 1015 has been marked as a duplicate of this bug. ***