Encoding Phase
This article discusses the encoding phase of an encoding job. You can find an overview of the entire encoding process in the Job Processing 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 |
|
Audio codecs |
|
Subtitles |
|
Containers |
|
Supported Aspect Ratios
The Encoding Service by default 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 |
When using aspect ratios 4:3 or 16:9 you may omit "VideoRepresentations" in the job request. Axinom Encoding will then use the default bitrate ladder, depending on the codec. For all other aspect ratios you must provide "VideoRepresentations" in the job request.
In case you need to use an aspect ratio that is not in above list you need to explicitly set "ForceAspectRatioToStandard": "False" in the job request.
Revision History
The table below lists the document versions and any changes to them.
| Version | Date | Description |
|---|---|---|
1.0 |
April 19, 2021 |
|
2.0 |
October 6, 2021 |
Added packaging-only mode |