Media Player Comparison
This web site currently provides two choices for media players:
HTML5 Video Player
Help with Other Preferences
Built-in Player Control Buttons
We have developed a set of standard HTML buttons for controlling both video players. However, each player also has its own built-in control bar that is turned off by default. Check this box if you would like to have the built-in control bar displayed in addition to our custom control bar. The built-in control bar will appear as an overlay on the video screen, and is invisible until you mouse over it. Due to its position on the video screen, it tends to conflict with the display of closed captions. Accessibility of the built-in player to keyboard users and screen reader users varies by browser and version.
If you check this box, closed captions will be displayed for all videos in either player. In the HTML5 player, captions are on by default but can be toggled off and on with the CC button on our custom control bar. In the JW Player, the CC button on our custom control bar is currently disabled because captions in the JW Player can not currently be toggled externally (this is expected to change in a future version of the JW Player). Instead, captions can be toggled using a CC button that appears as an overlay on the video display.
Closed Caption Font Size
This option only applies if the Closed Captions box is checked, and only applies in the JW Player. Caption size in the JW Player can only be changed here on this Preferences page. The HTML5 player uses the same font size as the rest of the text on the web site, and can be changed on-the-fly with the browser's zoom feature (in most Windows browsers, Ctrl + zooms in, Ctrl - zooms out; in most Mac browsers, Apple + zooms in, Apple - zooms out).
Closed Caption Language
This option only applies if the Closed Captions box is checked. We are currently in the process of producing non-English subtitles for many of our videos. The languages that are currently available are listed in the above form, although captions are not necessarily available in that language for all videos. Captions will be displayed in your preferred language when available. Otherwise they will be displayed in English.
Audio description is a separate narrative track that describes content that is otherwise presented visually. For a few of our more recent videos, closed audio description is available. With closed audio description, the narration is contained within a separate audio file, which allows it to be toggles off and on using an audio description button. Currently this is only supported by the JW Player, and can only be controlled by selecting the Audio Description button that appears on the video display (not the AD button that appears on our custom control bar). Both buttons are clearly labeled for screen reader users, and the latter is temporarily disabled until external control is available (expected in a future version of the JW Player). If you check this box, you will automatically be shown videos that have audio description mixed in to the program audio unless you're using the JW Player and closed audio description is available, in which case closed audio description will be used. If you prefer never using closed audio description, you can opt out by unchecking the Use closed audio description when available button.
Use Closed Audio Description When Available
As described in the preceding section, closed audio description allows the audio description track to be toggled off and on. This currently is experimental, and only available on newer videos in the JW Player. The ability to toggle audio description in the same way that one can toggle captions is an attractive feature. However, there currently are problems with its delivery. Most notably, the mute and volume buttons in the control bar effect only the program audio, not the audio description audio. Also, by default we set the audio description volume to be much higher than the program audio in order to assure that there's enough audio contrast for the description to be heard. However, if you increase the main volume, that increases only the program audio, not the audio description, which reduces or eliminates the contrast between the audio tracks.
Use Ducking with Closed Audio Description
This option only applies if the Audio Description and Use Closed Audio Description When Available are both checked, and only applies in the JW Player. As described in the preceding section, one problem with closed audio description is that the two separate audio tracks can have insufficient contrast, making it difficult to hear the description over the program audio. JW Player 5.0 introduced a new ducking feature, in which the player analyzes the audio description track and when narration is present, it ducks (temporarily lowers) the main program audio so that the description can easily be heard. This is an experimental feature and still has a few bugs. For example, after ducking it always returns the program audio volume to 9 (out of 10) regardless of what it had been set to previously. Also, the video typically begins playing before the player has finished analyzing the audio description wave form. Therefore, this feature doesn't typically work on narration that occurs early in the video. Also, this feature consumes a lot of computing resources and is not recommended for general use.
Display Audio Description Waveform
This option only applies if all boxes related to audio description are checked, and only applies in the JW Player. This is a debugging feature, designed to accompany the ducking feature described in the preceding section. It displays a waveform of the audio description track as an overlay across the video display. This obstructs the view of the video, and is not recommended for general use.
Highlight Transcript as Video Plays
This site includes interactive transcripts. On any transcript page, text is visibly highlighted as it is spoken in the video. This feature is only available with the HTML5 video player. Some users may find this distracting, so an option has been provided to disable it. To do so, simply uncheck the box.