Bug 455563

Summary: clip monitor: playback with forward speed of 1.5x is at the same speed of 1x
Product: [Applications] kdenlive Reporter: Shawn W <bigfly77>
Component: Rendering & ExportAssignee: Jean-Baptiste Mardelle <jb>
Status: RESOLVED DUPLICATE    
Severity: normal CC: fritzibaby, octavio, root, tocamgar
Priority: NOR Keywords: accessibility, akonadi-ports-regression, efficiency-and-performance, multiscreen, regression, release_blocker, usability, wayland-only
Version First Reported In: 21.08.1Flags: octavio: performance?
octavio: low_hanging?
octavio: MOVIT?
octavio: timeline_corruption?
Target Milestone: ---   
Platform: Microsoft Windows   
OS: Microsoft Windows   
URL: https://bugs.kde.org/enter_bug.cgi?alias=Decimally%20distorted%20anti-aliasing%20affecting%20readability%20on%20monitor%20displays&assigned_to=plasma-bugs%40kde.org&blocked=Blocking&bug_file_loc=http%3A%2F%2F&bug_severity=critical&cc=aleixpol%40kde.org&cc=jgrulich%40redhat.com&cc=nate%40kde.org&comment=ssue%20Summary%3A%0D%0AThere%20appears%20to%20be%20a%20recurring%20issue%20with%20the%20customizable%20GUI%20settings%2C%20particularly%20when%20multiple%20types%20are%20running%20simultaneously.%20This%20often%20results%20in%20system%20freezes%20and%20unexpected%20shutdowns%2C%20leaving%20users%20with%20a%20black%20screen%20and%20no%20indication%20of%20whether%20the%20system%20is%20rebooting.%20Manual%20reset%20and%20startup%20procedures%20are%20frequently%20required.%0D%0A%0D%0ASteps%20to%20Reproduce%3A%0D%0A%0D%0A%20%20%20%20Make%20any%20changes%20to%20the%20background%20settings%2C%20including%20the%20image%2C%20desktop%20integration%2C%20or%20window%20color%20from%20dark%20to%20light.%0D%0A%20%20%20%20Changes%20may%20take%20up%20to%2024%20hours%20to%20reconfigure%2C%20necessitating%20a%20backup%20reboot%20or%20sometimes%20a%20clean%20OS%20start%2C%20as%20the%20GUI%20fails%20to%20rebuild.%0D%0A%20%20%20%20Restarting%20in%20safe%20mode%2C%20booting%20from%20BIOS%2C%20or%20loading%20a%20system%20from%20boot%20usually%20restores%20the%20GUI.%20However%2C%20work%20is%20often%20lost%20while%20waiting%20for%20the%20image%20to%20buffer%20to%20a%20safe%20state%2C%20unless%20predefined%20correctly.%0D%0A%0D%0AObserved%20Result%3A%0D%0AThe%20system%20crashes%20frequently%2C%20causing%20damage%20to%20the%20graphical%20interface%20during%20boot%20and%20requiring%20a%20backup%20and%20restore%20from%20a%20working%20point%20or%20a%20system%20restore.%20Identifying%20the%20correct%20drivers%20has%20become%20challenging%20since%20the%20catalog%20changed%20with%20Windows%2011%20and%20the%20introduction%20of%20new%20chip%20architectures%20for%20memory.%0D%0A%0D%0AExpected%20Result%3A%0D%0AThe%20system%20should%20handle%20GUI%20changes%20smoothly%20without%20causing%20crashes%20or%20freezes.%20Any%20adjustments%20made%20to%20the%20GUI%20settings%20should%20be%20applied%20without%20necessitating%20a%20system%20reboot%20or%20resulting%20in%20loss%20of%20work.%0D%0A%0D%0ASoftware%2FOS%20Versions%3A%0D%0A%0D%0A%20%20%20%20Windows%208.%2010%2C%2011%0D%0A%20%20%20%20%20%20%20%20%20%20%20%20%20%20elementaryOS%0D%0A%20%20%20%20%20%20%20%20%20%20%20%20%20%20Ubuntu%2021.04%20LTS%0D%0A%20%20%20%20%20%20%20%20%20%20%20%20%20%20Kubuntu%2023.10.1%20Mantic%20Minotaur%20proposed.%0D%0A%0D%0A&component=general&contenttypemethod=autodetect&contenttypeselection=text%2Fplain&dependson=Compatibily&flag_type-35=X&form_name=enter_bug&keywords=regression%2C%20accessibility%2C%20GUI%2C%20Loading%2C%20multiscreen%2C%20%2C%20usability%2C%2C%20efficiency%2C%20&maketemplate=Remember%20values%20as%20bookmarkable%20template&op_sys=FreeBSD&product=xdg-desktop-portal-kde&rep_platform=Compiled%20Sources&see_also=This%20bug%20must%20be%20resolved%20before%20the%20bugs%20listed%20in%20this%20field%20can%20be%20resolved.%20&short_desc=The%20anti-aliasing%20settings%20on%20monitor%20displays%20are%20causing%20readability%20issues%20due%20to%20decimal-based%20adjustments.%20Text%20and%20graphics%20appear%20distorted%2C%20making%20it%20difficult%20for%20users%20to%20read.%20The%20problem%20persists%20despite%20attempts%20to%20adjust%20settings.%20Assistance&version=unspecified
Latest Commit: 2022-06-18 12:18:08 MST Version Fixed/Implemented In: Flagged?
Sentry Crash Report:
Bug Depends on: 471756    
Bug Blocks: 471156    
Attachments: clip monitor at 1.5x playback
Clip monitor x 1.5 speed forward plays at x 1 speed
Clip monitor 1.5X speed forward plays at 1X speed

Description Shawn W 2022-06-18 19:18:08 UTC 
Created attachment 149903 [details]
clip monitor at 1.5x playback

SUMMARY
***
NOTE: If you are reporting a crash, please try to attach a backtrace with debug symbols.
See https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports
***

I downloaded and installed the binary installer.
MLT version 7.1.0

STEPS TO REPRODUCE
1. Create a new project, and add a video clip (here it is of MP4 format).
drag the newly-added video clip to the tracks area.
2. click the clip monitor. Click the cursor in the timeline bar above the buttons.
3. click the forward button twice, and 1.5x is shown at the upper left corner in the monitor.
However, the playback speed is actually 1x. I timed with a stopwatch app (on mobile phone), and compared with the timestamp shown to the right of the forward button.
4. click the cursor in the timeline bar above the tracks.
click the forward button twice, and 1.5x is shown at the upper left corner in the monitor.
Playback speed is actually 1x.

OBSERVED RESULT
1x playback speed.

EXPECTED RESULT
1.5x playback speed.
When I click the forward button one more time, and 2x is shown and the playback speed is actually 2x.
So the 1.5x playback speed cannot be achieved.

SOFTWARE/OS VERSIONS
Windows: 10 21H2 (19044.1766).
macOS: 
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 
KDE Frameworks Version: 5.85.0
Qt Version: 5.15.2

ADDITIONAL INFORMATION
Same issue happened in Kdenlive for MacOS, v22.04.01.
I downloaded the binary installer.
KDE frameworks v5.94.0
Qt v5.15.2.
MLT 7.7.0.
MacOS version: Monterey v12.4
Comment 1 tocamgar 2022-09-13 22:17:28 UTC 
Created attachment 152037 [details]
Clip monitor x 1.5 speed forward plays at x 1 speed

This video attachment shows how x 1.5 speed forward plays video clip at normal speed (x 1 speed)
Comment 2 tocamgar 2023-06-17 13:32:06 UTC 
Created attachment 159744 [details]
Clip monitor 1.5X speed forward plays at 1X speed
Comment 3 emohr 2023-06-22 18:32:08 UTC 

*** This bug has been marked as a duplicate of bug 471156 ***