inconsistent "Always Fit Window" behavior in VLC for two different videos, one processed with MLT, the other with FFMPEG

[xmatic]

Two different videos:

• both have same resolution (1920 x 1080)
• one processed with Tencoder (frontend for FFMPEG), and the other processed with kdenlive (video editor that uses MLT framework)

The issue: they show up very differently in VLC.

• One needs "Menu > Video > Always Fit Window" to be checked to fill the screen.
• The other needs "Menu > Video > Always Fit Window" to be unchecked to fill the screen.

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Video 1: processed using kdenlive (video editor that uses MLT framework) [link][1]:

How the file looks in the file system:

kdenlive project settings:

kdenlive render profile:

The MLT command looks like this in kdenlive (screenshot):

The MLT command in text form:

ab=160k acodec=aac channels=2 crf=23 f=matroska g=15 movflags=+faststart preset=veryfast real_time=-1 threads=0 vcodec=libx264

MediaInfo:

VLC with "Always Fit Window" checked: video underfills the screen:

VLC with "Always Fit Window" unchecked: video fills the screen:

---

Video 2: processed using Tencoder (frontend for FFMPEG):

How the file looks in the file system:

Tencoder encode settings:

MediaInfo:

VLC with "Always Fit Window" checked: video fills the screen:

VLC with "Always Fit Window" unchecked: video overfills the screen:

---

Summary:

• despite the two videos having the same resolution (1920 * 1080)
• to fill the screen, one video needs "Always Fit Window" unchecked and the other needs it checked.

Question for you dear reader: What can I do in kdenlive or MLT so that the video fills the screen with "Always Fit Window" checked?

[ddennedy]

In Kdenlive project settings, the pixel aspect ratio and display aspect ratio are incongruent with the resolution: they do not mathematically make sense. Usually, only one pair of aspect ratio fields are provided to avoid this problem. I do not know why Kdenlive chooses this UI.

The MediaInfo for your Tencoder output shows an aspect ratio of 0.562. This is equivalent to a 9:16 aspect ratio vertical video. Probably in Kdenlive you want to use:
Resolution: 1080 x 1920 (notice the order is swapped from what you have)
Pixel aspect ratio: 1 / 1
Display aspect ratio: 9 / 16

This is actually more suitable for the Kdenlive discussion forum. MLT is primarily for developers, and Kdenlive is the app you are using that is responsible for how it uses MLT.

[bmatherly]

It looks like you are trying to make a vertical video. But your export settings do not form a vertical video:

I would suggest:
Size: 1080x1920
Pixel Aspect Ratio: 1x1
Display Aspect Ratio: 9x16

I am not a Kdenlive user and there are not any users around here. I recommend that you try the official Kdenlive support forum:
https://discuss.kde.org/tag/kdenlive

[xmatic]

ddennedy, bmatherly

Thank you to both of you. Both of you gave the same answer, and it worked.

This is an awesome community. I got the answer so quickly.

Thank you again.