Closed captions are transcriptions of the words spoken in a video/audio. Closed captions can be used to add clarity to video and audio files. Moreover, it increases the searchability and also assists those with hearing disabilities, an accessibility requirement for 508 ComplianceVIDIZMO supports Closed Captions (CC) for audio and video files. These can be added from the Media Settings either accessed from Media Management or while uploading media. 

VIDIZMO also renders automatic, machine generated transcriptions from transcoding providers such as Azure Media Services. In AMS, the encoding engine is called the Processor which uses the Dynamic Packager and the Indexer to transcode the media. The Dynamic Packager performs Transcoding, while the Indexer enables you to make the content of your media searchable and to generate a full-text transcript for closed captioning and keywords. 

VIDIZMO also offers the automatic generation of closed captions as an optional feature. This feature leverages AMS (Azure Media Services) in the background and involves enabling Closed Captioning Transcoding (Indexing) profiles for video and audio. Once enabled, all video and audio files uploaded in your channel will be indexed and closed caption files generated automatically.

To learn more, refer to the section in this article on how to Enable AMS' Machine Generated Transcriptions in VIDIZMO.

Depending upon the features enabled in VIDIZMO, Closed Captions can be shown as a searchable transcription alongside the video in a Transcription pane or can be shown below the video as subtitles or both. The feature that allows transcriptions to appear in the transcription pane is available for all VIDIZMO packages, with the exception of MediaTube Standard and available only when there is a closed caption associated with the media (either manually uploaded or automatically generated).

To learn more, refer to the section in this article on Learn To Work With Closed Captions In VIDIZMO.

VIDIZMO supports the following file formats for Closed Captioning:

  • WebVTT: The WebVTT format provides closed captions for video content, chapters for content navigation, text video descriptions, and any other metadata aligned with audio or video content.

  • AIB: Audio indexing blob file (AIB) is a binary file enabling search capability in a media file using a full-text feature of the SQL Server. The difference between VTT and AIB is that AIB also supports dialects. For example, if a word has a number of formations, it can be searched on all those formations, rather than do a hard-match of the query that was used to search the word.

  • SRT: SRT is one of the most basic of all subtitle formats with information on subtitle sequence, on-screen display time, and the actual subtitle text.

  • TTML: This is the Timed Text Markup Language file used for exchanging timed text information and delivering captions and subtitles.

Follow the steps below to setup Closed Captioning in VIDIZMO.


1. From the top menu bar, click on the Add New Media (+) icon.

2. While on the Add New Media page, click on Upload Media box.

3. Clicking on the Upload Media link brings up the Capture/Browse & Upload. Click on it to browse to the file's location.


4. Once the upload is complete, the page redirects to Media Settings. From the Basic tab, click on the Closed Caption Browse button.

5. A popup window to Upload appears:

i. Select the closed caption file from your device.

ii. Click on the Open button.

6. After browsing to the location of the Closed Caption file and selecting it, click on the Save button.

7.  If you also want the closed caption transcript to be displayed in full besides the video player, with the ability for users to search within the transcript, click on Publish tab, check Allow Transcription checkbox and click Save again.

8.  Navigate to the Channel Library, by clicking on Channel link at the navigation menu.

9. On the Channel Library page, select the media which has the Closed Captions added to it to open the media playback page.

10. On the Playback page, click on Closed Caption (CC) icon on the player controls to enable Closed Captions.

11. Closed Captions will be displayed on the video.

If Allow Transcription option is checked as specified in Step 7 above, the transcript of the Closed Captions will also appear in a pane on the right-hand side of the player. Please note that this pane only appears when the Allow Transcription checkbox is checked and when there is a closed caption associated with the media (either manually uploaded or automatically generated).

Re-uploading a Closed Captions file

There are instances, such as file corruption, modification to the transcript or corrections, which require the closed captions file to be re-uploaded. In such a case, you can select the video from the Media Manager and perform steps 4 to 6 as described in the previous section but this time you would need to remove the existing closed captions file first.

Here's how you can do it:

1. From the top navigation menu:

i. Select Admin

ii. Then select Media Management to list you published videos.

iii. Select the video against which the Closed Captions file needs to be replaced. Your selection should show up on the left panel as the selected video with the available options to perform.

iv. Click on the Settings button to open the Media Settings. 

v. The same screen, the Basic tab, will open as described in Step #4 of the previous section. Here you can see the "Remove Caption" link under the media thumbnail. 
Click on it to remove the previously uploaded CC file. 

vi. Once the previous file is removed, the link will change to "Browse" and you can continue to browse to the location and upload the new CC file.

vii. Upon successful upload, the new Closed Captions file will be available during video playback.

Enable AMS' Machine Generated Transcriptions In VIDIZMO

VIDIZMO renders automatic transcriptions for audio and video files if the encoding profile of a channel permits. During playback, a searchable transcript plays alongside the video enabling users to search within the transcript of the video to reach the desired moment within the video with ease. Moreover, by clicking on the transcript text, viewers can also jump to the desired section in a video. Through transcriptions, viewers can develop a better understanding of the content and context of the video. 

To generate automatic transcriptions of an audio/video file in a channel, the encoding provider must be set to AMS Dynamic Packaging. Since AMS uses artificial intelligence or machine learning to generate the transcriptions, there is a possibility of errors in the transcript. To help correct these errors, VIDIZMO allows Administrators to edit the transcription text during playback to minimize mistakes if there are any. 

Here is how you can enable transcriptions in VIDIZMO if you are using AMS as your transcoding provider: 


1. At the Account/Channel Homepage:

i. Go to Admin >>  ii. Control Panel.

iii. Make sure you have AMS Dynamic Packaging selected as your Encoding Provider.

iv & v. Select Video & Audio for Closed Captions_Azure Dynamic profiles and make sure they are "Enabled". These profiles are required to index the audio and video files that are uploaded to the channel.


2. Then upload media from the My Media link on the top-right corner:

Click here for more details on How To Upload Media

The next section explains how Transcript pane works in VIDIZMO.

Learn To Work With Transcript Pane In VIDIZMO

Viewers can perform the following actions on the closed caption transcript which appears in a pane on right-hand side of the player.

i. Search for a Term: Enter a term in the Search field and if the searched term is found, all of its instances get highlighted.

ii. Increase/ decrease the Font Size: Use the "A" icon to increase to decrease the font size in the transcript. Each subsequent click increases or decreases the font size.

iii. Edit the Transcript: The edit button puts the transcript into an editable mode in which text portions can be edited individually. If a line needs to be removed completely, use the "x" button when the transcript is in edit mode.

To apply the changes, use the ✔ check mark.

iv. Download the Transcript: To download the transcript, click on the Download icon. The transcriptions can be downloaded as an Excel file which will allow the viewers to view transcript in a readable format.

v. Navigate to any instance using comments: You can also navigate to any instance within a video through the comments:

i. Click on the Add comment (+) icon to add a comment.

ii. Enter your comment with the time you wish to link.

iii. Click on Check.

Click on the highlighted link in the comment.

You will be navigated to the required frame in the video.


For Allowing Transcription

Subject: Transcription

Action: Add

For Editing Transcript

Subject: Transcription

Action: Edit


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