# Step 2: Create captions selectors
After you have created a list of captions selectors, you can create the captions selectors in the event.
**To create the captions selectors**
1. In the event, in the **Input** section, choose **Advanced**.
1. Choose **Add Caption Selector**.
1. For **Source**, choose the format of the source captions.
To identify SMPTE-TT as the source captions, choose **TTML**. When Elemental Live ingests the captions, it automatically detects that they are SMPTE-TT.
1. For most formats, more fields appear. For details about a field, choose the Info link next to the field. In addition, see extra information about [DVB-Sub or SCTE-27](dvb-sub-or-scte27.md), on [Embedded](embedded.md), on [SCC](captions-input-scc.md), on [SMI, SRT, STL, TTML](captions-input-other-sidecars.md), on [teletext](teletext.md), or on [Null](captions-input-null.md).
1. Create more captions selector, as required.
# Information for DVB-Sub or SCTE-27
This section provides information specific to DVB-Sub or SCTE-27 input captions. It describes the fields that appear when you choose **DVB-Sub** or **SCTE-27** in the **Source** field in the **Caption Selector** section of the event. For more context, see the steps earlier in this section.
DVB-Sub and SCTE-27 formats are supported only in TS inputs. You must specify the location of the captions.
Complete the **PID** and **Language code** fields in one of the ways described in the following table. Each row in the table describes a valid way to complete these two fields.
****
| PID | Language code | Result |
| --- | --- | --- |
| Specified | Blank | Extracts the captions from the specified PID. |
| Blank | Specified | Extracts the captions from the first PID that Elemental Live encounters that matches the specified language. This might or might not be the PID with the lowest number. |
| Specified | Specified | Extracts the captions from the specified PID. Elemental Live ignores the language code, therefore we recommend you leave it blank. |
| Blank | Blank | Valid only if the source is DVB-Sub and the output is DVB-Sub. With this combination of PID and Language, all input DVB-Sub PIDs will be included in the output.Not valid for SCTE-27. |
# Information for embedded
This section provides information specific to embedded input captions. It describes the fields that appear when you choose **Embedded** in the **Source** field in the **Caption Selector** section of the event. For more context, see the steps earlier in this section.
Read this section if the input captions you have are any of the following: embedded (EIA-608 or CEA-708), embedded\$1SCTE-20, SCTE-20\$1embedded, or SCTE-20.
**Note**
For captions in VBI data: If you are extracting embedded captions from the input and using embedded captions in the output, and if the input includes VBI data and you want to include all that data in the output, then do not follow this procedure. Instead, see [Passing through VBI data](captions-in-vbi-data.md).
# Determining the number of captions selectors needed
To determine the number of captions selectors you need to created in the event, follow these rules:
+ **Embedded Passthrough** – Create only one captions selector. With this scenario, all languages are automatically extracted and are automatically included in the output.
+ **Embedded In, Other Out** – If you are setting up embedded-to-other, create one captions selector for each language that you want to include in the output, to a maximum of four selectors.
+ **A combination of Embedded passthrough and Embedded conversion** – If you are setting up embedded passthrough in some outputs and embedded-to-other in other outputs, create one captions selector for each language that you want to include in the output, to a maximum of four selectors. Do not worry about a selector for the embedded passthrough output. Elemental Live will extract all the languages for that output, even though no selector exists to explicitly specify this action.
# Completing the fields in the captions selector group
+ **Source**:
+ Choose embedded if the source captions are embedded (EIA-608 or CEA-708), embedded\$1SCTE-20, or SCTE-20\$1embedded.
+ Choose SCTE-20 if the source captions are SCTE-20 alone.
# Completing the fields in the CC channel number
+ **CC Channel number**: This field specifies the language to extract. Complete as follows:
+ If you are setting up embedded passthrough only (you are creating only one captions selector for the input embedded captions), this field is ignored, so keep the default.
+ If you are setting up embedded-to-another-format, (you are creating several captions selectors, one for each language), enter the number of the CC instance (from the input) that holds the desired language. For example, if this captions selector is intended to hold the French captions and the French captions are in event 2, enter 2 in this field.
+ **Force 608 to 708 Upconvert**: The embedded source captions can be EIA-608 captions, CEA-708 captions, or both EIA-608 and CEA-708. You can specify how you want these captions to be handled when Elemental Live is ingesting content. The following table describes the behavior for various scenarios.
[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/elemental-live/latest/ug/cc-fields.html)
+ **Use SCTE-20 if Embedded Unavailable**: This field appears only if you set the **Source** to **Embedded**. If the source captions combine embedded (EIA-608 or CEA-708) and SCTE-20, you might want to set this field to **Auto**. Elemental Live will give preference to the 608/708 embedded captions but will switch to use the SCTE-20 captions when necessary. If you set this field to Off, Elemental Live will never use the SCTE-20 captions.
# Information for SCC
This section provides information specific to SCC input captions. It describes the fields that appear when you choose **SCC** in the **Source** field in the **Caption Selector** section of the event. For more context, see this procedure.
SCC source captions are supplied in a captions file that is external to the video input. You must specify this file.
+ **External Caption File**: Specify the location of the file.
+ **Time Delta**: Complete this field to adjust the timestamp in the caption file. With the SCC files, the situation sometimes arises where the timestamp in the file for the first captions does not work with the video. The start time for the video/audio always 00:00:00. The start time of the captions may not be 00:00:00 – it may be some completely different, arbitrary time, such as 20:00:15. Assume that, in the video, the first words are spoken at 00:06:15. But given that the start time for the captions file is 20:00:15, then the time for the first caption will be marked as 20:06:30. This time will usually never work with the video. The solution is to adjust the times in the captions file. In this example, subtract 20 hours and 15 seconds (72015 seconds) from the captions file.
Enter a value in this field to push the captions earlier or later:
+ Enter a positive number to add to the times in the caption file. For example, enter **15** to add 15 seconds to all the times in the caption file.
+ Enter a negative number to subtract from the times in the caption file. For example, enter **-5** to remove 5 seconds from all the times in the caption file.
The format of the times in the captions does not have to match the value in the **Timecode Config** field (in the Input) of the video. The number you enter in this field will simply delay the captions or make the captions play earlier, regardless of the formats.
When using SCC, the video must absolutely have a value in the **Timecode Config **field. Otherwise the captions will not be inserted.
+ **Force 608 to 708 Upconvert**: SCC source captions are EIA-608 format and are contained in an external file. The options for converting the caption are the following:
+ Check: To convert the captions to CEA-708 format.
+ Unchecked: To leave the captions unconverted.
# Information for SMI, SMPTE-TT, SRT, STL, TTML
This section provides information specific to SMI, SMPTE-TT, SRT, STL, and TTML input captions. describes the fields that appear when you choose **SCC** in the **Source** field in the **Caption Selector** section of the **Create New Live Event** screen. For more context, see [Step 1: Identify the source captions that you want](identify-captions-in-the-input.md).
With these formats, the source captions are supplied in a captions file that is external to the video input. You must specify this file.
+ **External Caption File**: Specify the location of this file.
+ **Time Delta**: Complete this field to adjust the timestamp in the caption file. With the SCC files, the situation sometimes arises where the timestamp in the file for the first captions does not work with the video. With these types of captions, the start time for both the video/audio always 00:00:00. Assume that, in the video, the first words are spoken at 00:06:15. But in the captions file, this time is marked as 00:06:18, and every other caption is also off by 3 seconds. The solution is to adjust the times in the captions file. In this example, subtract 3 seconds from the captions file.
Enter a value in this field to push the captions earlier or later.
+ Enter a positive number to add to the times in the caption file. For example, enter **2** to add 2 seconds to all the times in the caption file.
+ Enter a negative number to subtract from the times in the caption file. For example, enter **-3** to remove 3 seconds from all the times in the caption file.
# Information for Teletext
This section provides information specific to Teletext input captions. It describes the fields that appear when you choose **SCC** in the **Source** field in the **Caption Selector** section of the event. For more context, see [Step 1: Identify the source captions that you want](identify-captions-in-the-input.md).
Teletext is a form of data that can contain several types of information, not just captions. Teletext can be present in SDI input, in MXF input, and in TS input, in which case it might be referred to as “DVB teletext.”.
You can set up to handle teletext in one of the following ways:
+ If you want to extract the entire teletext input, you must set up teletext passthrough. The entire teletext can never be converted to another format. Teletext passthrough is supported only in a TS output.
+ You can extract individual captions pages (the captions in a specific language) and convert them to another captions format.
+ You cannot extract individual captions pages (the captions in a specific language) and keep them in teletext.
# Determining the number of captions selectors needed
+ If you are setting up teletext passthrough captions, create only one captions selector, even if you want to include multiple languages in the output. With this scenario, all languages are automatically extracted and are automatically included in the output.
+ If you are setting up teletext-to-other, create one captions selector for each language that you want to include in the output. For example, one selector to extract English teletext, and one selector to extract Swedish teletext.
+ If you are setting up teletext passthrough in some outputs and teletext-to-other in other outputs, create individual selectors for the teletext-to-other, one for each language being converted. Do not worry about a selector for the teletext passthrough output. Elemental Live will extract all the data in the teletext, even though there is not a selector to explicitly specify this action.
# Completing the fields in the Captions Selector Group
+ **Source**: Choose **Teletext**.
+ **Page**: This field specifies the page of the desired language. Complete as follows:
+ If you are setting up teletext passthrough captions (you are creating only one captions selector for the input captions), leave blank: the value is ignored.
+ If you are converting teletext to another format (you are creating several captions selectors, one for each language), specify the page for the desired language. If you leave this field blank, you get a validation error when you save the event.
# Information for null
The list of sources in the **Sources** field for the caption selector includes the option **Null**. This source is not intended for stripping out captions. Instead, it is used for [608 XDS data](608-xds-handling.md).