Azure 点播媒体编码器概述和比较Overview and comparison of Azure on demand media encoders

编码概述Encoding overview

Azure 媒体服务提供了多个用于在云中对媒体进行编码的选项。Azure Media Services provides multiple options for the encoding of media in the cloud.

开始使用媒体服务时,了解编解码器与文件格式之间的区别很重要。When starting out with Media Services, it is important to understand the difference between codecs and file formats. 编解码器是实现压缩/解压缩算法的软件,而文件格式是用于保存压缩视频的容器。Codecs are the software that implements the compression/decompression algorithms whereas file formats are containers that hold the compressed video.

媒体服务所提供的动态打包,允许以媒体服务支持的流格式(MPEG DASH、HLS、平滑流式处理)传送自适应比特率 MP4 或平滑流式处理编码内容,而无须重新打包成这些流格式。Media Services provides dynamic packaging which allows you to deliver your adaptive bitrate MP4 or Smooth Streaming encoded content in streaming formats supported by Media Services (MPEG DASH, HLS, Smooth Streaming) without you having to re-package into these streaming formats.

创建 AMS 帐户后,会将一个处于“已停止”状态的默认流式处理终结点添加到帐户。When your AMS account is created a default streaming endpoint is added to your account in the Stopped state. 若要开始对内容进行流式处理并利用动态打包和动态加密功能,必须确保要从其流式获取内容的流式处理终结点处于“正在运行”状态。To start streaming your content and take advantage of dynamic packaging and dynamic encryption, the streaming endpoint from which you want to stream content has to be in the Running state.

媒体服务支持在本文中介绍的以下按需编码器:Media Services supports the following on demand encoders that are described in this article:

本文简要概述了按需媒体编码器,并提供了指向介绍更多详细信息的文章的链接。This article gives a brief overview of on demand media encoders and provides links to articles that give more detailed information. 本主题还提供对编码器的比较。The topic also provides comparison of the encoders.

默认情况下每个媒体服务帐户同时只能有一个活动的编码任务。By default each Media Services account can have one active encoding task at a time. 可以预留编码单元,使用它们可以同时运行多个编码任务,购买的每个编码预留单位对应一个任务。You can reserve encoding units that allow you to have multiple encoding tasks running concurrently, one for each encoding reserved unit you purchase. 有关信息,请参阅缩放编码单位For information, see Scaling encoding units.

Media Encoder StandardMedia Encoder Standard

如何使用How to use

如何使用 Media Encoder Standard 进行编码How to encode with Media Encoder Standard

格式Formats

格式和编解码器Formats and codecs

预设Presets

Media Encoder Standard 使用 此处所述的编码器预设之一进行配置。Media Encoder Standard is configured using one of the encoder presets described here.

输入和输出元数据Input and output metadata

此处说明了编码器输入元数据。The encoders input metadata is described here.

此处说明了编码器输出元数据。The encoders output metadata is described here.

生成缩略图Generate thumbnails

有关信息,请参阅如何使用 Media Encoder Standard 生成缩略图For information, see How to generate thumbnails using Media Encoder Standard.

修剪视频(裁剪)Trim videos (clipping)

有关信息,请参阅如何使用 Media Encoder Standard 剪裁视频For information, see How to trim videos using Media Encoder Standard.

创建覆盖层Create overlays

有关信息,请参阅如何使用 Media Encoder Standard 创建覆盖层For information, see How to create overlays using Media Encoder Standard.

另请参阅See also

媒体服务博客The Media Services blog

已知问题Known issues

如果输入视频不包含隐藏式字幕,输出资产仍包含一个空的 TTML 文件。If your input video does not contain closed captioning, the output Asset will still contain an empty TTML file.