Builder

Specify this setting only when your output will be consumed by a downstream repackaging workflow that is sensitive to very small duration differences between video and audio. For this situation, choose Match video duration. In all other cases, keep the default value, Default codec duration. When you choose Match video duration, MediaConvert pads the output audio streams with silence or trims them to ensure that the total duration of each audio stream is at least as long as the total duration of the video stream. After padding or trimming, the audio stream duration is no more than one frame longer than the video stream. MediaConvert applies audio padding or trimming only to the end of the last segment of the output. For unsegmented outputs, MediaConvert adds padding only to the end of the file. When you keep the default value, any minor discrepancies between audio and video duration will depend on your output audio codec.

When enabled, file composition times will start at zero, composition times in the 'ctts' (composition time to sample) box for B-frames will be negative, and a 'cslg' (composition shift least greatest) box will be included per 14496-1 amendment 1. This improves compatibility with Apple players and tools.

Ignore this setting unless compliance to the CTTS box version specification matters in your workflow. Specify a value of 1 to set your CTTS box version to 1 and make your output compliant with the specification. When you specify a value of 1, you must also set CSLG atom to the value INCLUDE. Keep the default value 0 to set your CTTS box version to 0. This can provide backward compatibility for some players and packagers.

Inserts a free-space box immediately after the moov box.

To place the MOOV atom at the beginning of your output, which is useful for progressive downloading: Leave blank or choose Progressive download. To place the MOOV at the end of your output: Choose Normal.

Overrides the "Major Brand" field in the output file. Usually not necessary to specify.