#SUBTITLES VS CLOSED CAPTIONS UPDATE#

You can update the manifest file to tell the player about the text tracks with the portal or with the Tracks API available as REST or with the SDKs. Media Services allows you to provide text tracks in WebVTT or TTML format. If you are concerned about the contents of the captions or subtitles being leaked in a secure delivery scenario, reach out to the Media Services support team for more information on the above guidelines for securing your content delivery. If you do not follow one of the guidelines above, your subtitles, captions, or timed-metadata text will be accessible as un-encrypted content that could be intercepted or shared outside of your intended client delivery path. Enable the CDN security features using Verizon Premium CDN or other 3rd-party CDN configured to connect to your Media Services streaming endpoints.

Use CDN token authentication to protect the text (subtitle, captions, metadata) tracks being delivered with short form tokenized URLs that are restricted to geo, IP, or other configurable settings in the CDN portal.

This method is supported by the Azure Media Player, but may not be supported on all devices and can require some client-side development work to make sure it succeeds on all platforms. These segments can then be decrypted by a client application after requesting the decryption key from the Media Services Key Delivery service using an authenticated JWT token.

#SUBTITLES VS CLOSED CAPTIONS FULL#

When enabling AES-128 clear key encryption, the text tracks can be configured to be encrypted using a full 'envelope' encryption technique that follows the same encryption pattern as the audio and video segments. To secure your captions, subtitles, or timed-metadata tracks, follow these guidelines:

#SUBTITLES VS CLOSED CAPTIONS MANUAL#

The lack of DRM encryption for text tracks limits your ability to secure the contents of live transcriptions, manual inserted captions, uploaded subtitles, or timed-metadata signals that may be inserted as separate tracks. The DRM subsystems, including PlayReady, FairPlay, and Widevine do not support the encryption and licensing of text tracks. The dynamic encryption and DRM features of Azure Media Services has limits to consider when attempting to secure content delivery that includes live transcriptions, captions, subtitles, or timed-metadata. Security considerations for closed captions, subtitles, and timed-metadata delivery Media Services delivers the content with inserted captions to your viewers. You need to use a live media encoder that can insert 608 or 708 captions in the encoded stream that's sent to Media Services. Currently, captioning is supported only if carried in the encoded input stream. ismt (Smooth Streaming text tracks), you can deliver the stream to only Smooth Streaming clients.ĬEA-708 and EIA-608 are closed-captioning standards for the United States and Canada.

#SUBTITLES VS CLOSED CAPTIONS MP4#

However, if you ingest fragmented MP4 (Smooth Streaming) with captions inside. Media Services dynamic packaging enables your clients to stream content in any of the following formats: DASH, HLS, or Smooth Streaming. You can also use this standard to easily add captions and subtitles to be consumed by a player client such as Azure Media Player.

This is the standard that Media Services uses for live transcription during live events which is provided by Azure Cognitive Services. WebVTT is the W3C standard for displaying timed text for the HTML5 text track element. The following table lists the types of captions supported by Media Services. The following caption/subtitle formats are supported by Media Services Captioning and subtitles You can use one text track for both a caption and subtitles, but implementation varies between video player clients. If an additional language text track is provided, it's considered a subtitle. Subtitles, are text tracks that show the speech and sounds in a different language than the source language.įor example, if the source language of a video is English, then the text track would be considered a caption. In general, captions are text tracks that are used for closed captioning that enables viewers who need accessibility features in a video player to understand what is being said and the sounds that exist in a video. This article discusses captions and subtitle formats. You can provide captions, subtitles and other text tracks to the client player.

#SUBTITLES VS CLOSED CAPTIONS CODE#

AMS website | Code Samples | Troubleshooting guide

Subtitles vs closed captions