Encode with an auto-generated bitrate ladder

Overview

This article explains how to use the Standard Encoder in Media Services to encode an input video into an auto-generated bitrate ladder (bitrate-resolution pairs) based on the input resolution and bitrate. This built-in encoder setting, or preset, will never exceed the input resolution and bitrate. For example, if the input is 720p at 3 Mbps, output remains 720p at best, and will start at rates lower than 3 Mbps.

Encoding for streaming

When you use the AdaptiveStreaming preset in Transform, you get an output that is suitable for delivery via streaming protocols like HLS and DASH. When using this preset, the service intelligently determines how many video layers to generate and at what bitrate and resolution. The output content contains MP4 files where AAC-encoded audio and H.264-encoded video is not interleaved.

To see an example of how this preset is used, see Stream a file.

Output

This section shows three examples of the output video layers produced by the Media Services encoder as a result of encoding with the AdaptiveStreaming preset. In all cases, the output contains an audio-only MP4 file with stereo audio encoded at 128 kbps.

Example 1

Source with height "1080" and framerate "29.970" produces 6 video layers:

Layer Height Width Bitrate (kbps)
1 1080 1920 6780
2 720 1280 3520
3 540 960 2210
4 360 640 1150
5 270 480 720
6 180 320 380

Example 2

Source with height "720" and framerate "23.970" produces 5 video layers:

Layer Height Width Bitrate (kbps)
1 720 1280 2940
2 540 960 1850
3 360 640 960
4 270 480 600
5 180 320 320

Example 3

Source with height "360" and framerate "29.970" produces 3 video layers:

Layer Height Width Bitrate (kbps)
1 360 640 700
2 270 480 440
3 180 320 230

Next steps