When a video file is large, completing the upload takes a correspondingly long time. Processing after upload in particular tends to take time, and may take tens of minutes or several hours or more depending on the file.
Much current video-editing software is designed with high-quality video and audio delivery in mind. When creating video teaching materials, the default settings can therefore easily produce files that are unnecessarily large.
The output file is often larger than the original. For example, when a video is exported from the Windows 11 built-in Microsoft Clipchamp with the default "1080p High Quality" setting, cases have been observed in which the file size becomes approximately ten times larger while video and audio quality remain almost unchanged.
(Clipchamp has other cautions as well; see the URL mentioned later.)
Please keep video file sizes as small as possible so that they do not place unnecessary pressure on the capacity of the servers available at Science Tokyo.
A relatively simple and highly effective way to prevent video files from becoming unnecessarily large is to reduce the frame rate at export.
The default frame rate is often set to "30 fps" or similar. This is excessively high for video teaching materials such as lectures and is a typical cause of unnecessarily large files.
For ordinary video teaching materials, "15 fps" is sufficient, and lowering the frame rate can substantially reduce the file size.
A high frame rate is generally intended to make rapidly moving footage appear smooth. For videos that mainly show PowerPoint slides being advanced, there is little benefit in using a high frame rate.
The audio bitrate, which affects sound quality, is also set high by default in much software. Reducing it can help reduce file size, especially for long videos.
For ordinary video teaching materials, "128 kbps" is sufficient.
For examples of how to adjust frame rate and bitrate, see the following guidance as appropriate.
https://isct-edu.tayori.com/q/lms-en/detail/1343731/