# Reference: Supported captions
<a name="supported-captions"></a>

This section provides reference information about the captions formats that Elemental Live supports.

**Topics**
+ [Supported caption formats](captions-supported-formats.md)
+ [Rules for extracting captions from sources](supported-containers-inputs.md)
+ [Rules for converting source captions to output captions](captions-support-tables.md)

# Supported caption formats
<a name="captions-supported-formats"></a>

<a name="table-captions-supported-formats"></a>[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/elemental-live/latest/ug/captions-supported-formats.html)

# Rules for extracting captions from sources
<a name="supported-containers-inputs"></a>

To use captions in a source, Elemental Live must be able to extract the captions. The rules are as follows:
+ Elemental Live can always extract sidecar captions from the source, so long as Elemental Live supports the captions format.
+ Elemental Live can always support captions from a streaming source, so long as Elemental Live supports the captions format and the input type.
+ Elemental Live can't necessarily extract captions from a file source. Even if Elemental Live supports the captions format, it can extract the captions only from specific container types. See the table that follows.


| Container in file input | Elemental Live can extract captions from the container? | 
| --- | --- | 
| Adobe Flash |   | 
| Audio Video Interleave (AVI) |   | 
| HLS | Yes | 
| Matroska |   | 
| MP4 | Yes | 
| MPEG Transport Stream (TS) | Yes | 
| MPEG-1 System Stream |   | 
| MXF | Yes | 
| No container | Yes | 
| QuickTime | Yes | 
| WAV | Yes  | 



# Rules for converting source captions to output captions
<a name="captions-support-tables"></a>

This section helps you to ensure that when creating an event or profile, you select a format that is valid for your output captions.

Various constraints exist for the caption formats that you can include in your content:
+  For a given input container, Elemental Live can parse certain caption formats. 
+ For a given input caption format, Elemental Live can create one or more output captions. However, a given output caption can appear only in specific output containers.

 In summary – starting with the output container you want to produce: 
+ A given output container supports a given set of output caption formats. This container constrains your choice of output captions. 
+ Furthermore, to produce each output caption format, you must use one of the compatible input caption formats .And you must select an input which can appear in the input container you have selected. So both which original input container and format you choose constrains your choice of output caption formats.

You must determine if it's possible for you to include the captions format that you want in your output. For example, assume that you want to include WebVTT captions in an HLS output. Assume that your captions source is in an MP4 container.You can implement this use case only if the MP4 container holds 608 embedded captions. You can't implement if, for example, the MP4 container holds ancillary captions. 

**Topics**
+ [Supported source captions and output captions in a GPP output container](captions-gpp-output-container.md)
+ [Supported source captions and output captions in a DASH output container](captions-dash-output-container.md)
+ [Supported source captions and output captions in an HLS output container](captions-hls-output-container.md)
+ [Supported source captions and output captions in an fMP4 output container](captions-hls-fmp4-output-container.md)
+ [Supported source captions and output captions in an MP4 output container](captions-hds-mp4-output-container.md)
+ [Supported source captions and output captions in MPEG2-TS or MPEG2-UDP](captions-mpeg2-ts-file-mpeg2-udp-streaming-output-container.md)
+ [Supported source captions and output captions in an MSS output container](captions-mss-output-container.md)
+ [Supported source captions and output captions in an MXF output container](captions-mxf-output-container.md)
+ [Supported source captions and output captions in a QuickTime output container](captions-quicktime-output-container.md)
+ [Supported source captions and output captions in a raw output container](captions-raw-output-container.md)
+ [Supported source captions and output captions in an RTMP output container](captions-rtmp-output-container.md)
+ [Supported source captions and output captions in a captions-only output container](captions-captions-only-output-container.md)

# Supported source captions and output captions in a GPP output container
<a name="captions-gpp-output-container"></a>

To read this table, find the type of container and captions from your input. The supported captions formats for this *output *container are then shown in the last column. 

<a name="table-captions-gpp-output-container"></a>[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/elemental-live/latest/ug/captions-gpp-output-container.html)

# Supported source captions and output captions in a DASH output container
<a name="captions-dash-output-container"></a>

To read this table, find the type of container and captions from your input. The supported captions formats for this *output *container are then shown in the last column. 

<a name="table-captions-dash-output-container"></a>[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/elemental-live/latest/ug/captions-dash-output-container.html)

# Supported source captions and output captions in an HLS output container
<a name="captions-hls-output-container"></a>

To read this table, find the type of container and captions from your input. The supported captions formats for this *output *container are then shown in the last column. 

<a name="table-captions-hls-output-container"></a>[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/elemental-live/latest/ug/captions-hls-output-container.html)

# Supported source captions and output captions in an fMP4 output container
<a name="captions-hls-fmp4-output-container"></a>

To read this table, find the type of container and captions from your input. The supported captions formats for this *output *container are then shown in the last column. 

<a name="table-captions-hls-fmp4-output-container"></a>[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/elemental-live/latest/ug/captions-hls-fmp4-output-container.html)

# Supported source captions and output captions in an MP4 output container
<a name="captions-hds-mp4-output-container"></a>

To read this table, find the type of container and captions from your input. The supported captions formats for this *output *container are then shown in the last column. 

<a name="table-captions-hds-mp4-output-container"></a>[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/elemental-live/latest/ug/captions-hds-mp4-output-container.html)

# Supported source captions and output captions in MPEG2-TS or MPEG2-UDP
<a name="captions-mpeg2-ts-file-mpeg2-udp-streaming-output-container"></a>

The table provides information about captions in an MPEG2-TS file output container or MPEG2-UDP streaming output container.

To read this table, find the type of container and captions from your input. The supported caption formats for this *output *container are then shown in the last column.

<a name="table-captions-mpeg2-ts-file-mpeg2-udp-streaming-output-container"></a>[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/elemental-live/latest/ug/captions-mpeg2-ts-file-mpeg2-udp-streaming-output-container.html)

# Supported source captions and output captions in an MSS output container
<a name="captions-mss-output-container"></a>

To read this table, find the type of container and captions from your input. The supported caption formats for this *output *container are then shown in the last column. 

<a name="table-captions-mss-output-container"></a>[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/elemental-live/latest/ug/captions-mss-output-container.html)

# Supported source captions and output captions in an MXF output container
<a name="captions-mxf-output-container"></a>

To read this table, find the type of container and captions from your input. The supported caption formats for this *output *container are then shown in the last column. 

<a name="table-captions-mxf-output-container"></a>[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/elemental-live/latest/ug/captions-mxf-output-container.html)

# Supported source captions and output captions in a QuickTime output container
<a name="captions-quicktime-output-container"></a>

To read this table, find the type of container and captions from your input. The supported caption formats for this *output *container are then shown in the last column. 

<a name="table-captions-quicktime-output-container"></a>[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/elemental-live/latest/ug/captions-quicktime-output-container.html)

# Supported source captions and output captions in a raw output container
<a name="captions-raw-output-container"></a>

This table describes the caption formats that can be included in a *raw output container that contains video*. For information about support when the captions are in a raw container on their own (independent of video), see [Supported source captions and output captions in a captions-only output container](captions-captions-only-output-container.md).

To read this table, find the type of container and captions from your input. The supported caption formats for this *output *container are then shown in the last column. 

<a name="table-captions-raw-output-container"></a>[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/elemental-live/latest/ug/captions-raw-output-container.html)

# Supported source captions and output captions in an RTMP output container
<a name="captions-rtmp-output-container"></a>

To read this table, find the type of container and captions from your input. The supported caption formats for this *output *container are then shown in the last column. 

<a name="table-captions-rtmp-output-container"></a>[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/elemental-live/latest/ug/captions-rtmp-output-container.html)

# Supported source captions and output captions in a captions-only output container
<a name="captions-captions-only-output-container"></a>

This table describes the caption formats that can be included on their own in an output. With this option, *the container is always a raw container that contains only the captions* (video would be in another container that may be a raw container or may be some other type).

If you have one of the source caption formats listed in the first column – regardless of the source container – you can convert it to an external captions file and include it in a raw container that contains only that captions file.

<a name="table-captions-captions-only-output-container"></a>[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/elemental-live/latest/ug/captions-captions-only-output-container.html)