Simplified Processing of Closed Captions and Subtitles

Automated Closed Caption Insertion, Extraction and Modification

We offer a comprehensive — and growing — set of tools for addressing caption insertion, extraction and modification. All of our cloud-processing capabilities are automated, greatly simplifying your ability to distribute subtitled and captioned video to millions of users.

 

Highlights

  • Support for the most-used caption formats, including CEA-608/708, DFXP, SCC, SRT, TTML and WebVTT

  • Seamlessly add captioning features through the Vantage Gateway API or GUI

  • Extract caption data from source video to create separate sidecar files (text)

  • Carry over caption data from source video, use caption sidecar file to create caption data in output videos, use existing sidecar files to convert to other caption sidecar files

  • Caption data modifications include time off-set, VTT segment duration and font size or source

  • CEA closed captions with SCTE-128 and SCTE-20 support

Reach More Viewers in More Places on More Devices

We were the first cloud processing service to offer universal closed captioning support specifically for broadcast intermediate and mezzanine assets for delivery to all devices. Our powerful, reliable, scalable feature set for closed caption workflows helps you to achieve critical business objectives, such as:

  • Assure compliance with impending Video Accessibility Act deadlines

  • Expand the size and demographic of your audience

  • Reduce time to market

  • Support popular learning tools

Unmatched Support

Through our API you can automate the manipulation and conversion of the most-used caption formats, including extracting and modifying multiple caption services and languages. In addition to rich support for sidecar and fragmented/packaged caption data for common formats such as fMP4 and HLS, we provide the ability to extract and insert a variety of ancillary and frame-based caption formats. Whether inside CableLabs-compliant transport streams, MPEG-2 program and transport streams, MXF containers, or H.264 and H.265 video streams, your video processing workflow can now support caption requirements for content distribution to all broadcast and OTT devices.

Closed Caption Features and Formats

Broadcast

  • Embedded DVB subtitles in MPEG-TS

  • SCTE 128 (A/53)

MXF

  • SMPTE 334-2 CDP

H.264 TS

  • CableLabs compliance

  • EIA-608 SCTE 128

MPEG-2 TS

  • CableLabs compliance

  • EIA-608 SCTE 128 w/ 708

  • EIA-608 SCTE 20 w/ 708

Multiple Service

  • EIA-608 CC 1-4, 708 Service 1-6

  • Multiple languages

  • International characters

Packaging

  • Timed-text

  • CEA-608 video track mux (with optional 708 up-conversion)

  • WebVTT sidecar

  • Burn-in

  • ISMT track

VANC Caption Extraction

  • A/53 708 DTVCC CDP extraction

  • H.264/H.265 embedded

Frame Caption Extraction

  • MPEG-2 transport streams containing MPEG-2 video

  • MPEG-2 program streams containing MPEG-2 video

  • A/53 and SCTE 20

Adjustments

  • EIA-708 up-conversion

  • Service reassignment

  • Re-timing

 

Simple Integration

Adding captions and subtitles is easy and affordable with the Vantage Gateway API. We offer XML templates for all popular devices, optimally configured for each, to further simplify your operation.

XML
<?xml version="1.0"?>
<query>
    <userid>[UserID]</userid> <!-- required-->
    <userkey>[UserKey]</userkey> <!-- required-->
    <action>[Action]</action> <!-- required-->
    <source>[SourceFile]</source> <!-- required-->
    <format>
        <output>[OutputFormat]</output> <!-- required-->
        <!-- Format params -->
        <closed_captions>
            <source>[CCSource]</source>
            <copy>[yes|no]</copy>
            <direct_copy>[yes|no]</direct_copy>
            <extract>[srt|scc|dfxp]</extract>
            <mux_type>[cea-608|cea-708|timed-text|webvtt|burn-in|ismt]</mux_type>
            <language>[LanguageCode]</language>
            <name>[NameCode]</name>
            <time_offset>[TimeOffset]</time_offset>
            <vtt_segment_duration>[SegmentDuration]</vtt_segment_duration>
            <font_source>[FontSourceURL]</font_source>
            <font_size>[FontSize]</font_size>
            <add_source_offset>[yes|no]</add_source_offset>
            <!-- add_source_offset feature works only with mxf source -->
            <ignore_cc_absence>[yes|no]</ignore_cc_absence>
            <cea_data_field>[0|1]</cea_data_field>
            <scte20>[yes|no]</scte20>
            <characteristics>[Characteristics]</characteristics>
            <accessibility_scheme>[Scheme]</accessibility_scheme>
            <accessibility_value>[Value]</accessibility_value>
            <timescale>[Timescale]</timescale>
            <cea_track_id>[TrackID]</cea_track_id>
        </closed_captions>
        <!-- Multiple closed captions params may be included in output format -->
        <closed_captions>
            <!-- closed captions params -->
        </closed_captions>
    </format></query>
JSON
{
    "query": {
        "userid": "[UserID]", // required
        "userkey": "[UserKey]", // required
        "action": "[Action]", // required
        "source": "[SourceFile]", // required
        "format": {
            "output": "[OutputFormat]", // required
            // Format params
            "closed_captions": [
                {
                    "source": "[CCSource]",
                    "copy": "[yes|no]",
                    "direct_copy": "[yes|no]",
                    "extract": "[srt|scc|dfxp]",
                    "mux_type": "[cea-608|cea-708|timed-text|webvtt|burn-in|ismt]",
                    "language": "[LanguageCode]",
                    "name": "[NameCode]",
                    "time_offset": "[TimeOffset]",
                    "vtt_segment_duration": "[SegmentDuration]",
                    "font_source": "[FontSourceURL]",
                    "font_size": "[FontSize]",
                    "add_source_offset": "[yes|no]",
                    // add_source_offset feature works only with mxf source
                    "ignore_cc_absence": "[yes|no]",
                    "cea_data_field": "[0|1]",
                    "scte20": "[yes|no]",
                    "characteristics": "[Characteristics]",
                    "accessibility_scheme": "[Scheme]",
                    "accessibility_value": "[Value]",
                    "timescale": "[Timescale]",
                    "cea_track_id": "[TrackID]"
                },
                {
                    // closed captions params
                }
            ]
        }
    }
}
 

Resources

  • Closed Captioning in the Cloud

    Closed Captioning in the Cloud

    Automated Closed Caption Processing for Broadcast and VOD Output

    Download →