Record sound and video in TSD

You will find the Media Capture web application at?data.tsd.usit.no/media-capture.

To make recordings, a camera ond/or a microphone must be available. The cameras and microphones used for video calls should work fine with the app. Recording sound?from the computer is only supported by certain browsers, see the table below.

When you start recording, data is continuously captured, encoded and securely transmitted for storage in your TSD project storage area, as a media file. If the recording stops prematurely, all data up to the point of failure is normally recoverable.

How to record video

Click Start Capturing to enable the data stream you want to record. The stream is now visible in the Capture Monitor.

Click Start Recording. You are now recording the stream shown by the monitor. You can pause, resume or end (stop) the recording at any time. When you finish recording the media file is published beside other imported files in you project area.

If a recording gets the same name as an earlier recording, the earlier recording will be deleted without warning.

How to record audio

Follow the procedure above, but ensure that the Capture Video?choice?besides Start Recording is left blank.

Changing resolution of video image

1. Click?Add Constraint?in the Video field under?Capture Setup.
2. Choose Height in the Name dropdown list.
3. Choose the appropriate type in the Type dropdown list, for example Must be at least.
4. Specify desired vertical resolution in?the Value column. 720 pixels is HD-Ready,?1080 is Full-HD, as per convention.
5. Click?Start Capturing to obtain a new stream of specified resolution.

The width of the stream will be automatically set to keep the aspect ratio from the camera.

Changing the source device

When recording from a camera or a microphone, you can choose which device to obtain the stream from as long as you have given your browser access to them.

1. Click the Add Constraint button in the Video field under?Capture Setup.
2. Choose Device in the drop-down list under?Name.
3. Depending on your preferences, choose Must be or Should be in the drop-down list under?Type.
4. Find and choose desired device in the list of devices under Value.
5. Click?Start Capturing?to obtain a stream from the specified device.

When recording a computer?screen and, optionally?audio from the?speakers, the web browser may ask you which part of the screen you want to capture, e.g. a particular window.?

Settings in Media Capture

The application page is partitioned into six field sets of recording functions.

The Capture Setup field set

Where you set up the stream from your capture device(s). You can tweak properties of the stream through specifying constraints.

The Add Constraint buttons

Choose?desired image resolution, frame rate, which device to use etc., with these buttons. You can also record without changing these settings. TSD will then choose appropriate defaults.

The Start Capturing button

Click this button to obtain a?capture stream for recording. Settings changed with the Add constraints buttons will affect this stream.?

The Capture Monitor

The capture monitor shows you your capture stream and allows you to assess the quality. The video element of the capture monitor allows you to view the stream image full-screen, and to hear/mute microphones (audio will be recorded regardless). You can reset the stream by adjusting constraints and using the Start Capturing button again.

The Recording Monitor

The recording monitor shows?your recording in real time.?If the quality of recording compared to the capture stream does not satisfy you,?stop recording and adjust encoding settings.?The stream can be watched full-screen, and the sound being recorded, can be muted (e.g. to prevent microphone echo from being recorded).

The Encoding field set

Allows you to specify media encoding preferences for recording. These affect the quality of the recording.

The Media type input field

Here you choose which format your recordings should be stored as. This affects file sizes. The default value ¡ª indicated by an empty field ¡ª should be good enough for most TSD projects. Supported formats or the value used by default, might be different from browser to browser.

The format of the field is a media type, specified by RFC 2046 and?RFC 6381.

The Bitrate input field

Here you can specify the bitrate for the recording, the volume of data to store per second in the recording file. It should not exceed the bandwidth of the network or storage (when playing back the file).

The Importing field?set

Preferences related to importing of the recording into the TSD project area.

The Filename input field

This field allows you to specify the name of the file storing the recording in the project area. Variables in the form of text like ${...} effectively define a pattern for the name of the recording. When recording starts, each ${...} part is automatically replaced with an appropriate value to make the name of the file storing the recording. It is advised to retain variables in the field so that each name can be different from the last, as recordings stored with the same name will overwrite the earlier recording without warning.

The Group input field

Specify the name of the group for the recording. If left?empty, TSD will use an appropriate default, which is normally <project-identifier>-members-group, the group of all project members.

The Recording?field set

Direct your recording with the Start, Stop, Pause and Resume buttons.?

Encoding of?media

Streams?from cameras with microphones?are not optimized for playback. Compression?is necessary?for playback. This entails a small?loss of quality while resulting in far more manageable?file sizes.?

All the settings the media capture application offers to control encoding, are contained in the Encoding field set.

The Mozilla Developer Network has published a number of articles which throw light on media encoding, container formats and video and audio codecs:

• Media container formats (file types)
• The "codecs" parameter in common media types
• Web video codec guide
• Web audio codec guide

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Browser requirements

Combinations not listed, with the general exception of later releases, should be assumed to only support the application partially or not at all.