Step 4: Design the encodes - AWS Elemental MediaLive

Step 4: Design the encodes

In the first step of planning the channel, you identified the video, audio, and captions encodes to include in each output group. In the third step, you organized these encodes into outputs in each output group.

You must now plan the configuration parameters for each encode. As part of this plan, you identify opportunities for sharing encodes among outputs in the same output group in the channel, and among outputs in different output groups in the channel.

Result of this procedure

After you have performed this procedure, you will have a list of video, audio, and captions encodes to create.

Plan the encodes

In Step 2: Map the output encodes to the sources, you sketched out a plan for the encodes you want to create in each output group. Below is the example of the plan from that step, showing the outputs and encodes, and the sources for those encodes.

At some point, you must fill in the details for the encodes identified in the second and third columns of this table. You have a choice:

  • You can decide these details now.

  • You can decide the details later, when you are actually creating the channel. If you decide to do this, we recommend you still read the procedures after the table, to get an idea of what is involved in defining an encode.

Example
Output group Type of encode Encode nickname

Characteristics of the encode

Source Identifier in source
HLS Video VideoA

AVC 1920x1080, 5 Mbps

HEVC PID 600
VideoB

AVC 1280x720, 3 Mbps

HEVC PID 600
VideoC AVC 320x240, 750 Kbps HEVC PID 600
Audio AudioA AAC 2.0 in English at 192000 bps AAC 2.0 PID 759
AudioB AAC 2.0 in French at 192000 bps AAC 2.0 PID 747
Captions CaptionsA

WebVTT (object-style) converted from embedded, in English

Embedded Channel 4
CaptionsB WebVTT (object-style) converted from embedded, in French Embedded Channel 2
RTMP Video VideoD AVC 1920x1080, 5Mbps HEVC PID 600
Audio AudioC Dolby Digital 5.1 in Spanish Dolby Digital 5.1 PID 720
Captions CaptionsC RTMP CaptionInfo (converted from embedded) in Spanish Embedded Channel 2
Archive Video VideoE AVC, 1920x1080, 5 Mbps HEVC PID 600
Audio AudioD Dolby Digital 2.0 in Spanish AAC 2.0 PID 746
AudioE Dolby Digital 2.0 in French AAC 2.0 PID 747
AudioF Dolby Digital 2.0 in English AAC 2.0 PID 759
Captions CaptionsD DVB-Sub (object-style) converted from Teletext, in 6 languages. Teletext PID 815

Design the details for each video encode

For each video encode in your table, you have already identified the source asset, codec, resolution and bitrate. You must now identify all the other encoding parameters you need to set.

Follow this procedure for each individual video encode.

  1. Look at the fields in the video encode section of each output. To view these fields, follow these steps. Don't worry about not completing all the sections. You only want to display the video encode fields, and you will then cancel the channel.

    • On the MediaLive home page, choose Create channel, and in the navigation pane, choose Channels.

      If you've created a channel before, you won't see the home page. In that case, in the MediaLive navigation pane, choose Channels, and then choose Create channel.

    • On the Create channel page, under Output groups, choose Add.

      Don't worry that you haven't completed any of the earliers sections in the channel. You are only trying to display all the fields for the video encode.

    • In the Add output group section, choose HLS and choose Confirm.

    • Under that output group, choose Output 1.

    • In the Output section, go to the Stream settings section, and choose the Video link.

    • In the Codec settings field, choose the codec that you want for this video encode. More fields appear. Choose the field labels for all the sections to display all the fields.

  2. In each section, determine whether you need to change the defaults.

    • Many of the fields have defaults, which means you can leave the field value as is. For details about a field and its default value, choose the Info link next to the field.

    • There are some fields that you might need to set according to instructions from your downstream system, to match the expectations of the downstream system.

    • There are some fields where the value you enter affects the output charges for this channel. These are:

      • The Width and Height fields (which define the video resolution).

      • The Framerate fields.

      • The Rate control fields.

      For information about charges, see the MediaLive price list.

    • You can read about some of the fields in the following sections:

  3. Make detailed notes about the values for all the fields you plan to change. Do this for every video encode that you identified.

Design the details for each audio encode

For each audio encode in your table, you have already identified the source asset, codec and bitrate. You must now identify all the other encoding parameters you need to set.

Follow this procedure for each individual audio encode.

  1. Look at the fields in the audio encode section of each output. To view these fields, follow the same steps as for the video encodes, but choose the Audio 1 link.

    With audio encodes, there aren't many fields for each code. But the fields for the codecs are very different from each other.

  2. Study the fields and make notes.

Design the details for each captions encode

For each captions encode in your table, you have already identified the source captions, format, and language. You must now identify all the other encoding parameters you need to set.

Follow this procedure for each individual captions encode.

  1. Look at the fields in the captions encode section of each output. To view these fields, follow the same steps as for the video encodes, but choose Add caption to add a captions section, because there is no captions section by default.

    With captions encodes, there aren't many fields for each captions format. But the fields for the formats are very different from each other.

  2. Study the fields and make notes.

Identify encode sharing opportunities

If you have already identified the details for all the output encodes, you can now identify opportunities for encode sharing.

If you plan to identify details later, we recommend that you come back to this section to identify opportunties.

Read about encode sharing and encode cloning in Sharing encodes among outputs.

You will use encode sharing and encode cloning when you create the encodes in the channel, starting with Step 6: Set up the video encode.

  • When you have a complete list, compare the values for the encodes:

    • If you have two (or more) encodes with identical values, you can share the encode. When you create the channel, you can create this encode once, in one output. You can then reuse that encode in other outputs. The procedure for creating the encode provides detailed instructions for reusing.

      Keep in mind that two encodes are identical only if they are identical in all their fields, including sharing the same video source. For example, in the sample table earlier in this section, the first video encode for HLS and the video encode for RTMP share the same video source.

    • If you have two (or more) encodes with nearly identical values, you can clone an encode to create a second encode, and then change specific fields in the second encode. The procedure for creating the encode provides detailed instructions for cloning.

    Then identify opportunities for sharing, in the same way as you did for the video encodes. Keep in mind that two encodes are identical only if they are identical in all their fields, including sharing the same audio source.

    Carefully identify the video encodes to share by noting the outputs and output groups each belongs to.

Then identify opportunities for sharing, in the same way as you did for the video encodes. Keep in mind that two encodes are identical only if they are identical in all their fields, including sharing the same captions source.

Example

Following from the example in the earlier steps in this section about channel planning, you might decide you have these opportunities shown in the last two columns of this table.

Encode nickname

Characteristics of the encode

Source Opportunity Action
VideoA

AVC 1920x1080, 5 Mbps

HEVC Create this encode from scratch.
VideoB

AVC 1280x720, 3 Mbps

HEVC Clone Clone VideoA and change the bitrate. Perhaps also other fields.
VideoC AVC 320x240, 750 Kbps HEVC Clone Clone VideoA and change the bitrate and perhaps other fields.
AudioA AAC 2.0 in English at 192000 bps AAC 2.0 Create this encode from scratch.
AudioB AAC 2.0 in French at 192000 bps AAC 2.0 Clone Clone AudioA and change the audio selector (the reference to the source) to the selector for French. Perhaps also change other fields.
CaptionsA

WebVTT (object-style) converted from embedded, in English

Embedded Create this encode from scratch.
CaptionsB WebVTT (object-style) converted from embedded, in French Embedded Clone Clone CaptionsC and change the captions selector (the reference to the source) to the selector for French. Perhaps also change other fields.
VideoD AVC 1920x1080, 5Mbps HEVC Share Share VideoA
AudioC Dolby Digital 5.1 in Spanish Dolby Digital 5.1 Create this encode from scratch.
CaptionsC RTMP CaptionInfo (converted from embedded) in Spanish Embedded Clone Clone CaptionsA and change the captions selector (the reference to the source) to the selector for Spanish. Perhaps also change other fields.
VideoE AVC, 1920x1080, 5 Mbps HEVC Share Share VideoA
AudioD Dolby Digital 2.0 in Spanish AAC 2.0 Create this encode from scratach. Although its source is the same as Aa, its output codec is different, which means all its configuration fields are different. Therefore, there is no advantage to cloning.
AudioE Dolby Digital 2.0 in French AAC 2.0 Clone Clone AudioD and change the audio selector (the reference to the source) to the selector for French. Perhaps also change other fields.

Don't clone AuduioB because AudioB and AudioA have different output codecs. Therefore, there is no advantage to cloning.

AudioF Dolby Digital 2.0 in English AAC 2.0 Clone Clone AuduioD and change the audio selector (the reference to the source) to the selector for English. Perhaps also change other fields.

Don't clone AudioB because AudioB and AudioF have different output codecs. Therefore, there is no advantage to cloning.

CaptionsD DVB-Sub (object-style) converted from Teletext, in 6 languages. Teletext Create this encode from scratch.