Success Criterion 1.2.3 - Level A
Audio Description or Media Alternative (Prerecorded)
Ensure a transcript or audio description is provided for videos where you can't hear what is displayed. The content can then be read in case of a transcript, or heard in case of audio description. If you choose to add a audio description, you also meet success criterion 1.2.5.
Impact
A transcript is useful for anyone who has trouble understanding video frames.
People who are blind can hear what can be seen in videos through an additional audio track.
Check
“Is a transcript or audio description available for all videos?”
This can be tested visually, no assistive technologies are needed.
Solution
Add transcript
On Android, you can use a TextView to display written text. Don't forget to put it in a ScrollView, to make the text scrollable.
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Appt transcript" />
</ScrollView>Add audio description
As of Android 4.1, the MediaPlayer has support for multiple audio tracks. Use the selectTrack method to select the correct audio track.
The code example belows shows a basic implementation of selecting an audio description track embedded inside a video.
val player = MediaPlayer.create(this, R.raw.video)
try {
player.trackInfo.forEachIndexed { index, trackInfo ->
if (trackInfo.trackType == TrackInfo.MEDIA_TRACK_TYPE_AUDIO) {
player.selectTrack(index)
return@forEachIndexed
}
}
player.start()
} catch (e: Exception) {
e.printStackTrace()
}