CRITICAL: Podcast Recording Bug (All Versions) - Black Padding/Resolution Mismatch Triggered by Runtime Quality Change

[mshahedi83]

Describe the bug

The Podcast recording feature in OpenBoard (both DEB 1.7.1 and Flatpak 1.7.3) suffers from a severe resolution mismatch and a corrupted metadata error.

1. Resolution Mismatch / Black Padding: The bug is triggered when the quality setting is changed during runtime (e.g., changing from Medium to Full). The resulting video file (e.g., 1364 × 696) has a correct resolution (on my device, when the video is recorded correctly in 'Full' mode, it has the same dimensions.) but the recorded resolution is smaller than the output resolution. (maybe the same as the 'Medium' mode resolution) This problem leads to significant black, empty padding areas on the right and bottom of the video frame. This makes the recorded video file unusable for clean display.

   • This padding issue is reproducible in both the older DEB 1.7.1 and the current Flatpak 1.7.3 versions.
   • The bug's appearance is sensitive to the graphics driver state (e.g., switching NVIDIA Prime modes can temporarily fix or trigger it).

2. Metadata Bug (1000 FPS): All output video files contain corrupted metadata, reporting the Frame Rate as 1000.00 frames per second.

You can take a look at my attached files.

To Reproduce

1. Open OpenBoard 1.7.3 (Flatpak) or 1.7.1 (DEB).
2. Ensure the Podcast quality setting is currently set to Medium.
3. Open the Podcast recording controls.
4. Crucial Step: Change the recording quality from Medium to Full while the application is running.
5. Record a short video.
6. Observation: The video file will display large black padding on the right and bottom, confirming the resolution mismatch.

Expected behavior

1. The dimensions/resolution of the output video file should perfectly fill by the recorded content, eliminating all black padding, regardless of when the setting is changed.

2. The file metadata should correctly report the video's actual frame rate (e.g., 4.75 fps or 5 fps).

Actual behavior

1. The padding issue is systematically triggered by changing the recording quality at runtime. (the content resolution (maybe same the 'Medium' output resolution) 1024 × 520 is mismatched with the output resolution 1364 × 696.)

2. The video file metadata incorrectly displays the Frame Rate as 1000.00 fps (in file properties).

Screenshots

Screenshot 1: Files app, FPS is wrong:

Screenshot 2: VLC, FPS is correct:

Additional resources

Video_1_OBS_PADDING_REPRO_1.7.3.mp4.mp4

Video_2_OUTPUT_1.7.3_WORKING.mp4

Video_3_OUTPUT_1.7.3_PADDING.mp4

Context

• reproducibility : systematic (when triggered by runtime change)
• OpenBoard version : 1.7.3
• bug happens with : 1.7.3 (Flatpak) AND 1.7.1 (DEB)
• bug doesn't happen with : N/A
• didn't check : other versions
• OS : Linux Ubuntu 20.04.6 LTS (Focal Fossa)
• bug happens with : Linux Ubuntu 20.04.6 LTS (Focal Fossa)
• bug doesn't happen with : N/A
• didn't check : Windows macOS
• Installation source : Flatpak (via GNOME Software Center) and DEB (via dpkg)

Additional context

My device specifications are as follows:

Lenovo Ideapad 320-15ISK

• OS: Linux Ubuntu 20.04.6 LTS
• Display: 1366 × 768
• CPU: Intel Core i3-6006U
• GPU: NVIDIA Geforce 920MX
• RAM: 12GB DDR4 (4GB (Originally) + 8GB)
• Storage: 1TB HDD

• Metadata Note: The 1000 FPS error only shows up in the Ubuntu Files application properties, not in specialized players like VLC.

The bug is temporarily fixed by closing and reopening the application after a graphics mode change, but the 1.7.1 DEB file before the Prime Select switch serves as the original working state.

However, if you open OpenBoard and set Podcast to 'Full', close the OpenBoard and reopen it (the OpenBoard and therefore the Podcasts feature will open in 'Full' mode) and record a video, the problem does not occur and the content dimensions are detected correctly.