![5e7383edff0f8e6e3c4967b0_sw-logo-black-1.png]](https://help.syncwords.com/hs-fs/hubfs/5e7383edff0f8e6e3c4967b0_sw-logo-black-1.png?height=40&name=5e7383edff0f8e6e3c4967b0_sw-logo-black-1.png){kind=logo}
In this step, you will configure where and how your processed captions, subtitles, and dubbed audio are delivered. For a list of all steps see our Service Wizard Steps below.
Stream Type: Select SRT as your stream type.
Delivery Method: Choose how your output stream will be delivered. You can select between PUSH and PULL.
SRT PUSH (Caller)
Use this option when your encoder or external platform will receive the output stream from the Service. This setup is ideal for workflows where the platform pushes the generated captions, subtitles, and dubbed audio to a specified endpoint.
Stream URL: Enter the destination SRT address where the Service should send the output stream.
Passphrase (optional): If your receiving endpoint requires encryption, enter the Passphrase used for decryption in this field.
Buffer: Set the buffer duration in seconds to manage latency and ensure stable output transmission. The default 30 second buffer is recommended when using translated subtitles and dubs. For low latency delivery of same language captions we recommend using a value between 0-5.
Captions & Subtitles: Additional configuration options are available in the Captions & Subtitles section. Details about these optional settings are listed below.
Advanced Settings: Additional configuration options are available in the Advanced Settings section. Details about these optional settings are listed below.
SRT PULL (Listener)
Use this option when the receiving system will connect to SyncWords to fetch the output stream. This is commonly used in workflows where the destination system acts as the SRT receiver.
IMPORTANT: The streaming URL and credentials will be available after the service setup is complete.
Passphrase (optional): Enter an optional passphrase to encrypt your SRT stream. Use this if your receiving system requires encrypted transport for security or compliance.
Buffer: Specify the buffer duration for the output stream.
Latency allows perfected timing of captions, subtitles, and dubbing with the audio in the stream.
-
The default 30-second buffer is recommended when using translated subtitles and dubs, as it provides sufficient time for processing multilingual outputs.
-
For low latency delivery of same language captions, we recommend using a value greater than your HLS segment size or a minimum 5 second buffer to maintain stability.
Captions & Subtitles
This section allows you to configure how captions and subtitles are inserted into your output stream.
Click to expand and select the delivery method that best matches your requirements and player compatibility - you can choose Embedded 608, DVB-TTML, DVB-SUB, DVB-TXT or opt for No Subtitles from the dropdown.
CRITICAL: Verify Player Compatibility
Before selecting an embedding format, confirm that your destination platform or video player supports your chosen format. Not all players support all delivery methods.
If your captions are not displaying at your destination, verify format compatibility first. Contact your platform provider or consult their documentation for supported caption formats.
Embedded 608
Use this format for traditional closed captions, commonly used in North American broadcast television. Embedded 608 are embedded directly into the video signal and are widely supported by legacy devices and players
CC1 Channel: Select the language that will be delivered through the CC1 channel using the dropdown menu. By default, the primary source language (such as English) is assigned to CC1.
CC2–CC4 Channels: Use these channels to deliver additional languages alongside CC1. If you have enabled translations in Step 4: Translation, they will be automatically populated to channels CC2–CC4. Select the language you want to send to each channel using the corresponding dropdown menu.
Manage CC Channels: Use the buttons below the channel list to manage your closed captions channels:
-
Add Channel - Click to add a new channel (up to CC4) and select a language from the dropdown
-
Remove Channel - Click to remove the last added channel
IMPORTANT: Not all players support reading Embedded 608 from CC2-CC4. Please make sure to verify that your player has this capability before moving forward.
NOTES: If your source stream already contains captions in CC1, select the "Passthrough" option from the dropdown list to have those captions passed through to the destination. This is typically used when you want to preserve existing CC1 captions from your source without modification, while SyncWords processes other caption channels or languages
Line Count: Defines how many caption lines are displayed per segment on screen. Use the numeric field or slider to set your preferred line count.
Position (from top): Controls the vertical position of the caption text on the output video. Use the slider or numeric input to set the distance from the top of the screen where captions begin. 3 is the top of the screen, 15 is the bottom.
TIP: Keep the number of lines in mind when you set the positioning. New captions will appear on the row selected, older captions will roll up to the row above it. So, if you set 3 lines and start on row 15 you will see captions on rows 15, 14 and 13.
DVB-TTML (Text)
Creates TTML (Timed Text Markup Language) based subtitle tracks. This text-based format is more flexible for styling but has specific language support. Your output will include embedded DVB-TTML subtitle tracks for all enabled languages.
You can customize the appearance of TTML captions by clicking on the Subtitle Style & Formatting option.
A modal will appear with the following configuration options:
Max Line Length: Set the maximum line length for TTML captions. This controls how many characters can appear on a single line before wrapping to the next line.
Speaker Label: Set the speaker label separator used for speaker diarization. This character or symbol appears between speaker labels and their dialogue in the captions.
Bottom Margin: Set the bottom margin as a percentage of the viewport height. This controls the vertical spacing between the subtitles and the bottom edge of the screen.
IMPORTANT: Speaker diarization must be enabled in your Transcription settings for speaker labels to appear in the captions.
Action Buttons
After configuring your settings, you will see the following actions:
-
Cancel - Discard your changes and close the modal without saving
-
Reset to defaults - Restore all settings to their default values
-
Apply Changes - Save your customized appearance settings and close the modal
DVB-SUB (Bitmap)
Creates bitmap/image-based subtitle tracks embedded in the stream. This format provides pixel-perfect rendering and supports all languages. Your output will include embedded DVB-SUB bitmap subtitle tracks for all languages.
You can customize the appearance of DVB- SUB captions by clicking on the Subtitle Style & Formatting option.
A modal will appear with the following configuration options:
Horizontal Alignment: Set the horizontal position of the subtitle text on the screen. Available options include start and center.
Speaker Label: Set the speaker label separator used for speaker diarization. This character or symbol appears between speaker labels and their dialogue in the captions.
IMPORTANT: Speaker diarization must be enabled in your Transcription settings for speaker labels to appear in the captions.
Font Size: Set the font height as a percentage of the video height. Use the slider to adjust the size from smaller to larger values.
Bottom Margin: Set the bottom margin as a percentage of the video height. This controls the vertical position of subtitles from the bottom of the screen.
Foreground Color: Set the font color for subtitle text using RGBA format (Red, Green, Blue, Alpha).
Background Color: Set the background box color behind subtitle text using RGBA format.
Action Buttons
After configuring your settings, you will see the following actions:
-
Cancel - Discard your changes and close the modal without saving
-
Reset to defaults - Restore all settings to their default values
-
Apply Changes - Save your customized appearance settings and close the modal
DVB-TXT (Teletext)
Creates teletext-based subtitle tracks, a legacy format still used in some broadcast workflows. Your output will include embedded DVB-TXT teletext subtitle tracks for all supported languages.
After selecting DVB-TXT, two configuration options become available:
Language–Page Mapping
Click the Language–Page Mapping button to specify the teletext page numbers for each language in your output stream.
A modal will appear displaying all languages configured in your Service. For each language, you can specify a teletext page number.
Page (100-899): Enter the teletext page number where each language's subtitles will be available. Valid page numbers range from 100 to 899.
NOTE: Teletext page numbers must be unique for each language. Common broadcast conventions use pages 888, 777, or other specific numbers depending on regional standards.
Subtitle Style & Formatting
Click the Subtitle Style & Formatting button to customize the appearance of DVB-TXT teletext subtitles.
A modal will appear with the following configuration options:
Row: Set the starting row for subtitle display on the teletext page. With double-height, each line uses 2 rows. It ranges from 1-23.
Line Count: Set the number of subtitle lines to display on screen at one time.
Max Line Length: Set the maximum number of characters per line before text wraps to the next line. Use the slider to adjust the value.
Horizontal Alignment: Set the horizontal position of the subtitle text on the screen. Available options include start and center.
Speaker Label: Set the speaker label separator used for speaker diarization. This character or symbol appears between speaker labels and their dialogue in the captions.
IMPORTANT: Speaker diarization must be enabled in your Transcription settings for speaker labels to appear in the captions.
Double Height: Enable this toggle to use double-height letters for improved readability. When enabled, subtitle text appears twice as tall as standard teletext characters.
Foreground Color: Select the color for the subtitle text from the dropdown menu. Available options include red, green, yellow, blue, magenta, cyan and white.
Action Buttons
After configuring your settings, you will see the following actions:
-
Cancel - Discard your changes and close the modal without saving
-
Reset to defaults - Restore all settings to their default values
-
Apply Changes - Save your customized appearance settings and close the modal
No Subtitles
Select this option if you do not want captions or subtitles embedded in the output stream. You may still deliver captions through sidecar files or other methods configured elsewhere.
NEXT STEP: Once you’ve entered the required information, click "Continue" to move to Step 6: Preview where you will preview & create your Service.
Navigation Options
At the bottom of the screen, you will see the following actions:
- Cancel - Cancels the creation of your Service and exits the wizard.
- Reset - Clears all fields and settings in the Wizard so you can start over.
- Step Back - Returns to the previous step if you need to modify earlier settings.
- Continue - Moves to the next step of the wizard once the required fields are completed.
NOTE: If you click off the Wizard without Resetting or Canceling your inputs will be saved and you can return to complete the setup later.
Your Service is not created until you have been through all 6 steps and clicked the "Create Service" button.
Advanced Settings
To access the Advanced Settings, click the Advanced Settings dropdown on the page. This section provides optional configuration parameters that help optimize caption embedding, audio encoding, and stream behavior depending on your output type.
Options (SRT Protocol Options): Use this setting to specify SRT protocol key-value pairs in URL syntax. These parameters allow advanced control over how the stream is pulled from your source destination.
NOTES:
- This field appears only when SRT PULL (Listener) is selected as your Output method.
- Incorrect values may affect stream stability or performance.
Latency: Set the SRT protocol minimum latency in seconds. This controls the buffer time used by the SRT protocol to compensate for network jitter and packet loss.
Default Dub Codec: Select the audio codec used for synthesized dubbing tracks in the output stream. Available codecs include AAC (ADTS) and PCM(302M).
Dub Track Order: Select where synthesized dubbing tracks appear in the output PMT (Program Map Table) relative to the original audio tracks. Available options includes afterAllOriginal, afterOriginalAudio and beforeOriginalAudio.
Enable Frame Reordering: Enable this option to support framerate-independent caption embedding.
Late Caption Timeout: Set a threshold (in seconds) after which captions arriving too late should be skipped. This prevents outdated captions from appearing on screen if they are delayed beyond a reasonable limit.