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Copy file name to clipboardExpand all lines: articles/media-services/latest/live-event-types-comparison.md
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---
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title: Azure Media Services LiveEvent types | Microsoft Docs
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description: This article shows a detailed table that compare LiveEvent types.
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description: This article shows a detailed table that compares LiveEvent types.
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services: media-services
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documentationcenter: ''
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author: Juliako
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ms.tgt_pltfrm: na
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ms.devlang: ne
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ms.topic: article
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ms.date: 03/01/2019
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ms.date: 06/13/2019
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ms.author: juliako
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---
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## Types comparison
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The following table compares features of the Live Event types.
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The following table compares features of the Live Event types.
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| Feature | Pass-through Live Event | Standard or Premium1080p Live Event |
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| --- | --- | --- |
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## System presets
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The resolutions and bitrates contained in the output from the live encoder is determined by the [presetName](https://docs.microsoft.com/rest/api/media/liveevents/create#liveeventencoding). If using a **Standard** live encoder (LiveEventEncodingType.Standard), then the *Default720p* preset specifies a set of 6 resolution/bit rate pairs described below. Otherwise, if using a **Premium1080p** live encoder (LiveEventEncodingType.Premium1080p), then the *Default1080p* preset specifiesthe output set of resolution/bit rate pairs.
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The resolutions and bitrates contained in the output from the live encoder is determined by the [presetName](https://docs.microsoft.com/rest/api/media/liveevents/create#liveeventencoding). If using a **Standard** live encoder (LiveEventEncodingType.Standard), then the *Default720p* preset specifies a set of 6 resolution/bit rate pairs described below. Otherwise, if using a **Premium1080p** live encoder (LiveEventEncodingType.Premium1080p), then the *Default1080p* preset specifies the output set of resolution/bit rate pairs.
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> [!NOTE]
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> You cannot apply the Default1080p preset to a Live Event if it has been setup for Standard live encoding - you will get an error. You will also get an error if you try to apply the Default720p preset to a Premium1080p live encoder.
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### Output Video Streams for Default720p
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**Default720p** will encode the input video into the following 6 layers.
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If the contribution feed is of 720p or higher resolution, the **Default720p**preset will encode the feed into the following 6 layers. In the table below, Bitrate is in kbps, MaxFPS represents that maximum allowed frame rate (in frames/second), Profile represents the H.264 Profile used.
> If you need to customize the live encoding preset, please open a support ticket via Azure Portal. You should specify the desired table of resolution and bitrates. Do verify that there is only one layer at 720p, and at most 6 layers. Also do specify that you are requesting a preset for a Standard live encoder.
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> The specific values of the bit rates and resolutions may be adjusted over time
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### Output Video Streams for Default1080p
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**Default1080p** will encode the input video into the following 6 layers.
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If the contribution feed is of 1080p resolution, the **Default1080p**preset will encode the feed into the following 6 layers.
> If you need to customize the live encoding preset, please open a support ticket via Azure Portal. You should specify the desired table of resolution and bitrates. Do verify that there is only one layer at 1080p, and at most 6 layers. Also do specify that you are requesting a preset for a Premium1080p live encoder.
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> The specific values of the bit rates and resolutions may be adjusted over time.
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### Output Audio Stream for Default720p and Default1080p
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For both *Default720p* and *Default1080p* presets, audio is encoded to stereo AAC-LC at 128 kbps, sampling rate of 48 kHz.
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## Implicit properties of the live encoder
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The previous section describes the properties of the live encoder that can be controlled explicitly, via the preset - such as the number of layers, resolutions, and bitrates. This section clarifies the implicit properties.
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### Group of pictures (GOP) duration
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The live encoder follows the [GOP](https://en.wikipedia.org/wiki/Group_of_pictures) structure of the contribution feed - which means the output layers will have the same GOP duration. Hence, it is recommended that you configure the on-premises encoder to produce a contribution feed that has fixed GOP duration (typically 2 seconds). This will ensure that the outgoing HLS and MPEG DASH streams from the service also has fixed GOP durations. Small variations in GOP durations are likely to be tolerated by most devices.
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### Frame rate
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The live encoder also follows the durations of the individual video frames in the contribution feed - which means the output layers will have frames with the same durations. Hence, it is recommended that you configure the on-premises encoder to produce a contribution feed that has fixed frame rate (at most 30 frames/second). This will ensure that the outgoing HLS and MPEG DASH streams from the service also has fixed frame rates durations. Small variations in frame rates are likely to be tolerated by most devices, but your on-premises live encoder should not be dropping frames (eg. under low battery conditions).
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### Resolution of contribution feed and output layers
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The live encoder is configured to avoid upconverting the contribution feed. As a result the maximum resolution of the output layers will not exceed that of the contribution feed.
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For example, if you send a contribution feed at 720p to a Live Event configured for Default1080p live encoding, the output will only have 5 layers, starting with 720p at 3Mbps, going down to 1080p at 200 kbps. Or if you send a contribution feed at 360p into a Live Event configured for Standard live encoding, the output will contain 3 layers (at resolutions of 288p, 216p, and 192p). In the degenerate case, if you send a contribution feed of, say, 160x90 pixels to a Standard live encoder, the output will contain one layer at 160x90 resolution at 200 kbps.
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### Bitrate of contribution feed and output layers
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The live encoder is configured to honor the bitrate settings in the preset, irrespective of the bitrate of the contribution feed. As a result the bitrate of the output layers may exceed that of the contribution feed. For example, if you send in a contribution feed at a resolution of 720p at 1 Mbps, the output layers will remain the same as in the [table](live-event-types-comparison.md#output-video-streams-for-default720p) above.
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