The encoding phase is also a part of the whole encoding process. In this phase, both the video and audio are encoded with a specific codec

Encoding Phase

This article discusses the encoding phase of an encoding job. You can find an overview of the entire encoding process in the Encoding Overview article.

In the Encoding phase, the video and audio are encoded using a specific Codec. Audio is always encoded using AAC (Advanced Audio Coding, successor of MP3). It is also possible to skip encoding using a packaging-only mode, if the video is provided in the desired format already. For video encoding, the following parameters under ContentProcessing apply:

{
    "ContentProcessing" : {
        ...
        "VideoFormat": "H264",
        "OptimizeFor": "Balance",
        ...
    }
}

VideoFormat specifies the codec. Supported values are:

  • H264 - H.264 (AVC = Advanced Video Coding) (default, used if omitted)

  • H265 - H.265 (HEVC = High Efficiency Video Coding). It is supported by Safari, but please note that whole streams or some representations (1080p or better) might not be available with H.265 on some older Macs (for example, MacBook Pros made in 2014).

  • DoNotEncode - don’t encode the video at all, see packaging-only mode.

OptimizeFor can have the values "Speed", "Quality", or "Balance". If you require faster encoding and highest quality is not necessary for you, go with Speed. On the other hand, use Quality for the best output, but slowest processing. Balance is the optimal and default mode: it provides a decent processing time with good quality. This property has no impact if the VideoFormat is DoNotEncode.

Supported Input

The Encoding Service supports a variety of video, audio, and subtitles formats. The table below lists the formats known to be supported. There are likely many more formats which are also processed well. Let Axinom know if you have any issues with a specific format.

Video codecs

AVCHD, DNxHD, DVCPRO, DVCPROHD, H.264/AVC, H.265/HEVC, MPEG-1 Video, MPEG-2 Video, MPEG-4 Video, ProRes, Theora, VP6, VP8, VP9

Audio codecs

AAC, AC3, AIFF, FLAC, MP2, MP3, Ogg Vorbis, WAV, WMA

Subtitles

WebVTT, TTML, SubRip (=SRT), PAC

Containers

3GP, AVI, DIVX, FLV, GXF, M4V, MKV, MOV, MP4, MPEG-2 PS, MPEG-2 TS, MPG, MTS, MXF, QuickTime, RM, SWF, VOB, Webm, WMV

Supported Aspect Ratios

The Encoding Service supports a variety of Display Aspect Ratio (DAR) values for input video. The list includes:

16:9

4:3

1.896:1

3:2

2.11:1

2.35:1

2.66:1

Revision History

The table below lists the document versions and any changes to them.

Version Date Description

1.0

April 19, 2021

  • Initial version.

2.0

October 6, 2021