No duration data after convert

[alvisecastagna1]

Good afternoon, i'm try to detect the video duration but after finished converting there are no duration data in blob file.

Here the option code:

var options = { controls: true, fluid: false, plugins: { record: { audio: true, video: { mandatory: { minWidth: 1280, minHeight: 720, }, }, frameWidth: 1920, frameHeight: 1080, videoMimeType: 'video/webm;codecs=H264', maxLength: 100, debug: true, convertEngine: 'ts-ebml' } } };