Knowledge Base

The Playback Control Window

With the Playback Control window you can:

• Start, pause and stop an observation.
• Control playback of video files, audio files and other data sets (event log, external data).
• Review segments of video, audio and other data sets.

Some playback control buttons are hidden by default. Others can be hidden.

Playback Control Buttons

• Start Observation – Starts the observation.
• Stop Observation – Stops the observation.
• Pause/Still – Pauses the video/audio. Pressing the space bar toggles between Pause and Play forward at speed 1.
• Play Forward at Speed 1 – Plays the video at the normal play speed. Pressing the space bar toggles between Pause and Play forward at speed 1.
• Increase Speed – Increases the forward or backward playback speed by one step.
• Decrease Speed – Decreases the forward or backward playback speed by one step.
• Quick Review – Reviews the latest segment of video/audio, for example to check that an event was scored at the correct time or to add/edit events. Press the button multiple times to let the video jump back more. The video segment plays back at lower speed. Set the review length and speed in the Project Settings. Quick Review is also useful when carrying out Instantaneous Sampling during an offline observation. After clicking the Next and Previous Sample button, use the Quick Review button to get more information about which behavior the subjects are performing. To pause the video before quick review, set the quick review playback speed to 0. To pause the video after quick review, select the checkbox in front of Pause Playback After Quick Review. These settings are found in the Playback Control Options tab of the Project Settings.
• Loop – Activates a loop to replay a fragment a number of times. The procedure depends on whether you chose User Defined or Fixed Interval for Loop Options in the Playback Control Options tab of the Project Settings window.
  • User Defined – Replays the entire observation or a segment. Two flags appear when you click the Loop button, one at the start and one at the end of the slider. Move these flags to select a segment. Click the Loop button again to stop the loop.
  • Fixed Interval – A fixed interval can be useful to score whether an event occurs in fixed time fragments (1-0 sampling). The flags show an interval with the length specified in the Playback Control Options tab of the Project Settings window. Move the flags to the episode you want to replay. You can move the flags in increments equal to the interval length defined in the Playback Control Options tab. For example, if the interval length is 10 seconds, you can position the start of the loop at 0 s, 10 s, 20 s, etc. If the interval length is 30 seconds, you can position the start at 0 s, 30 s, 60 s, etc. Use the shortcut key Ctrl+K (next interval) and Ctrl+J (previous interval) to jump to another interval.
• Step Forward – Moves the video one frame forward. Moves audio files 1 second forward. When clicked during video playback, the video is paused and moves one frame forward.
• Step Backward – Moves the video one frame backward with each click. Moves audio files 1 second backward. When clicked during video playback, the video is paused and moves one frame backward.
• Time – Shows the time elapsed from the start time of the observation. If you select to display Remaining Time, it is possible that the remaining time plus elapsed time in the event log is not exactly the total duration due to rounding of decimals.
• Playback Speed Indicator – Indicates the current playback speed.

Playback Speed Notes

• The available playback speeds depend on the video frame rate and video format. In general, speed ranges from 1/25 or 1/30 to +16 playing forward, and from -1/25 or -1/30 to -16 playing backward.
• If the audio is spoken language, you will not be able to hear what subjects say when playing audio slower or faster. In most cases no sound is heard when playing forward at 2x or faster, or backward at any speed.
• Occasionally during scoring, playback of the audio file may appear to jolt slightly. This is purely a cosmetic effect; the data being scored still have accurate time stamps.
• If you have multiple video files and one has fewer available speeds than others, only those speeds are available for all videos.
• If you select to display Remaining Time, it is possible that the remaining time plus elapsed time in the event log is not exactly the total duration due to rounding of decimals.

Optional Playback Control Buttons

The following buttons are hidden by default. To show them, choose Setup > Project Settings > Playback Control Options and select the desired buttons.

• Play Backward at Speed 1 – Plays the video/audio/event log backward at normal play speed.
• Jump to Begin – Moves the video/audio/event log to the start.
• Jump to End – Advances the video/audio/event log to the end.
• Volume Control – Move the slider to increase or decrease the volume of the audio file. The volume control works independently from the Windows volume control. Click the speaker icon to mute or unmute the sound.

If an offset exists between video/audio/data streams, clicking Jump to Begin or Jump to End positions playback at the start of the earliest or latest stream. For example, if the event log starts one minute after the first video frame, clicking Jump to Begin positions at the start of the earliest stream, which is the video.

Playback Control Buttons for Live Scoring

The following buttons are only available when Live Observation is selected under Observation Source in the Project Setup.

• Suspend Observation – Suspends the current observation.
• Resume Observation – Resumes the current observation.

Playback Control Buttons for Instantaneous Sampling

The following buttons are only available when Instantaneous Sampling or Combine Continuous and Instantaneous Sampling is selected under Observation Method in the Project Setup.

• Previous Sample – Moves the video/audio to the previous instantaneous sample.
• Next Sample (Ctrl+Shift+Up Arrow) – Moves the video/audio to the next instantaneous sample.

Customizing the Playback Control Window

• To show and hide buttons, see Optional Playback Control Buttons.
• To resize and move the Playback Control window, see Position and Resize the Windows on the Screen.
• To customize the time interval represented by the slider, see Slider Range.