Bug 455918 - If you downscale the video/image using Kdenlive's effect or composition, it will destroy image's quality
Summary: If you downscale the video/image using Kdenlive's effect or composition, it w...
Status: RESOLVED FIXED
Alias: None
Product: kdenlive
Classification: Applications
Component: Video Effects & Transitions (other bugs)
Version First Reported In: 21.12.2
Platform: Snap Linux
: NOR major
Target Milestone: ---
Assignee: Vincent PINON
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2022-06-25 13:48 UTC by KZopen
Modified: 2022-10-24 20:01 UTC (History)
0 users

See Also:
Latest Commit:
Version Fixed/Implemented In:
Sentry Crash Report:


Attachments
This archive contains .pdf report and 3 images (1.16 MB, application/zip)
2022-06-25 13:48 UTC, KZopen
Details

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Description KZopen 2022-06-25 13:48:35 UTC
Created attachment 150145 [details]
This archive contains .pdf report and 3 images

SUMMARY

The report title already says, what is the problem. 
But TLDR - Kdenlive's effect "Transform" (and composition), when scaling down the picture, does not take in consideration all the pixels. It takes in consideration only the "closest pixel/s". This leads to crippled image quality, because majority of pixels are ignored. This should not happen and has been in Kdenlive for a very very long time.

In attachment I have added a .pdf report and the image files, which were used in the test. I made a .pdf report, because in order to describe the problem in detail, you have to read and look at the comparison pictures.


STEPS TO REPRODUCE
1. Read the .pdf report pls
2. Read the .pdf report pls
3. Read the .pdf report pls

OBSERVED RESULT
Image with destroyed quality

EXPECTED RESULT
Image without destroyed quality

SOFTWARE/OS VERSIONS
Ubuntu 22.04
Comment 1 KZopen 2022-10-24 20:01:30 UTC
Good news. The issue has been fixed in kdenlive-22.08.2 . I tested and the issue still exists in kdenlive-22.08.1. So, it means the issue was solved in the last version.