Transcoding

When you add a video file to the schedule, the system will determine if the video file can be used directly, or if it needs to be automatically converted to a different video format first. This process is called transcoding.

Uploading video content that doesn't need to be transcoded saves time and resources, and ensures that the video looks exactly the same as on your own computer.

Video files that need to be transcoded will be marked with this icon in the article details:

Video files that can be used directly will have this icon instead:

Rules

To avoid transcoding, the video file needs to have one of the following formats:

H.264 (AVC), in an MP4 container, using Constant Rate Factor (CRF) encoding, with a minimum value of CRF=18.

H.265 (HEVC), in an MP4 container, using Constant Rate Factor (CRF) encoding, with a minimum value of CRF=20.

We recommend using H.264 when possible. Consider using H.265 when the video has a 4K resolution or higher, and H.264 for videos with lower resolutions.

For details on how to produce files in these formats, consult the documentation for your video production software. The industry standard software for advanced video encoding is FFmpeg.

Other considerations

For video files that don’t conform to the above rules, the following rules will apply:

  • If the total number of pixels (width × height) is greater than 4096x2048x1.1, the video will be transcoded to H.265 with CRF=27, and downscaled such that the the total number of pixels equals 4096x2048x1.1.
  • Otherwise, if either dimension is greater than 2000 pixels and the total number of pixels (width × height) is greater than 1920×1080, the video will be transcoded to H.265 with CRF=27.
  • Otherwise, the video will be transcoded to H.264 with CRF=23.

The default CRF value for H.264 is 23, and for H.265 the default is 28. These values are considered to be a good tradeoff between file size and quality, but if you want better quality you can set a lower CRF yourself.

Videos that will be downscaled will be marked with this icon in the article details:

For PowerPoint content, the content will always be converted to an H.264 video with a resolution of either 1080x1920 or 1920x1080.

Regardless of the format, there’s currently a hard file size limit of 2 GB for all content uploaded through the CMS. Files that exceed this limit will be marked with this icon in the article details:

If you have any questions about transcoding or video formats, please contact our support department.