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Dynamic Media already comes with a predefined Adaptive Video Encoding profile. The settings in this out-of-the-box profile are optimized to give your customers the best viewing experience possible. When you encode your master videos using the Adaptive Video Encoding profile, during playback the video player automatically adjusts the quality of the video stream based on the Internet connection speed of your customers. This is known as adaptive streaming.
The following are other factors that determine the quality of your videos:
- Resolution of the uploaded master video
If the MP4 video was recorded at a lower resolution, such as 240p or 360p, it cannot be streamed in high definition. - Video player size
By default, the "Width" in the Adaptive Video Encoding profile is set to “Auto.” Again, during playback, the best quaility is used based on the size of the player.
See also Best Practices for Video Encoding.
Hinweis:
To generate a video's metadata and associated video image thumbnails, the video itself needs to go through the encoding process in Dynamic Media. Metadata is useful when you are searching for assets. The thumbnails are static video images that are generated during encoding. They are required by the AEM system and used in the user interface to help you visually identify videos in the Cards view, Search Results view, and the Asset List view. You can see the generate thumbnails when you tap the Renditions icon (a painter's palette) of an encoded video.
When you are done creating the video profile, you apply it to a folder or mutliple folders. See Applying a Video Profile to Folders.
The following table identifies best practice encoding profiles for adaptive video streaming to mobile and tablet devices, and desktop computers. You can use these presets for any aspect ratio video.
| Video Format Codec | Video Bitrate (Kbps) | Keep Aspect Ratio? | Video Size Width/Height (Pixels) | Video Frame Rate (Fps) | Audio Codec | Audio Bitrate |
MP4 H.264 (mp4) |
800 | Yes | auto x 360 | 30 | Dolby HE-AAC | 128 |
MP4 H.264 (mp4) |
1400 | Yes | auto x 480 | 30 | Dolby HE-AAC | 128 |
MP4 H.264 (mp4) |
2600 | Yes | auto x 720 | 30 | Dolby HE-AAC | 128 |
Dynamic Media already comes with a predefined Adaptive Video Encoding profile--a group of video upload settings for MP4 H.264-- that is optimized for the best viewing experience. You can use this profile when you upload your videos.
However, if this predefined profile does not meet your needs, you can choose to create your own adaptive video encoding profile. When you use the setting Encode for adaptive streaming--a best practice--all encoding presets that you add to the profile are validated to ensure that all videos have the same aspect ratio. In addition, the encoded videos are treated as a multi-bitrate set for streaming.
When you create the video encoding profile, you will notice that most encoding options are pre-populated with recommended default settings to help you. However, if you select a value other than the recommended default, be aware that it may result in poor video quality during playback and other performance issues.
So, for all MP4 H.264 video encoding presets in the profile, the following values are validated to ensure that they are the same across individual encoding presets in the profile, thereby making adaptive streaming is possible:
- Video Format Codec - MP4 H.264 (.mp4)
- Audio Codec
- Audio Bitrate
- Keep Aspect Ratio
- Two Pass Encoding
- Constant Bitrate
- H264 Profile
- Audio Sampling Rate
If the values are not the same, you can continue creating the profile as is. However, be aware that adaptive streaming will not be possible. Instead, users will experience single-bitrate streaming. It is recommended that you edit the encoding settings to use the same values across individual encoding presets in the profile.
See also Creating a video encoding profile for progressive streaming.
See also Best Practices for Video Encoding.
When you are done creating the video profile, you apply it to a folder or multiple folders.
You can view the error.log file to monitor the progress of an encoding job, to see if encoding is finished, or to see any job errors. The error.log is found in the logs folder where your instance of AEM is installed.
If you choose not to use the option Encode for adaptive streaming, be aware that all encoding presets that you add to the profile are treated as individual video renditions for single-bitrate streaming or progressive video delivery. Also, there is no validation to ensure that all the video renditions have the same aspect ratio.
The supported video format codec is H.264 (.mp4).
See also Creating a video encoding profile for adaptive streaming.
See also Best Practices for Video Encoding.
When you are done creating the video profile, you apply it to a folder or multiple folders.
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(Optional) Do one of the following:
- Tap the Advanced tab, and make sure the Use Default Values check box is selected (recommended).
- Clear the Use Default Values check box and specify the video settings and audio settings you want.
Tap ? next to each option for additional descriptions or recommended settings based on the selected video format codec.
You can edit an existing video encoding profile to take advantage of advanced video encoding parameters that are not found in the user interface when you create or edit a Video Profile in AEM. You custom add one or more advanced parameters--such as minBitrate and maxBitrate--to your existing profile.
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In the panel on the lower-right side of the page, from the Properties tab, specify the Name, Type, and Value of the parameter you want to use.
The following advanced parameters are available to use:
Name Description
Type
Value h264Level H.264 level to use for encoding. Normally this is automatically determined based on the encoding settings you are using. String 10 * h264 level
For example, 3.0 = 30, 1.3 = 13)
No default value.
keyframe The target number of frames between keyframes. Calculate this value to generate a keyframe every 2-10 seconds. For example, at 30 frames per second, the keyframe interval should be 60-300.
Lower keyframe intervals improve stream seeking and stream switching behavior for adaptive video encodings and may also improve the quality for videos that have lot of motion. However, because keyframes increase a file's size, a lower keyframe interval usually results in lower overall video quality at a given bitrate.String Positive number.
Default is 300.
Recommended value for HLS (HTTP Live Streaming) is 60-90.
minBitrate Minimum bitrate to allow for variable bitrate encodings, in Kbps (kilobits per second).
This parameter only applies when Use Constant Bitrate is deselected in the Advanced tab when you create or edit a video encoding profile.
See also Bitrate.
String Positive number, in Kbps.
No default value.
maxBitrate Maximum bitrate to allow for variable bitrate encodings, in Kbps.
This parameter only applies when Use Constant Bitrate is deselected in the Advanced tab when you create or edit a video encoding profile.
See also Bitrate.
String Positive number, in Kbps.
No default value. However, the recommended value is up to two times of the encoding bitrate.
audioBitrateCustom Set value to true to force a constant bitrate for the audio stream, if supported by audio codec. String true/false
Default is false.
Recommended value for HLS (HTTP Live Streaming) is false.
You can edit any video encoding profile you have created to add, edit, or delete video presets within that profile.
However, it is recommended that you do not edit the predefined Adaptive Video Encoding profile that came with Dynamic Media. Instead, you should copy the profile and save it. You can then edit the desired presets.
See also Best Practices for Video Encoding.
To edit a video encoding profile:
When you assign a video profile to a folder, any subfolders automatically inherit the profile from its parent folder. This means that you can assign only one video profile to a folder. As such, consider carefully the folder structure of where you upload, store, use, and archive assets.
If you assigned a different video profile to a folder, the new profile overrides the previous profile. The previously existing folder assets remain unchanged. The new profile is applied on the assets that are added to the folder later.
Folders that have a profile assigned to it are indicated in the user interface by the name of the profile appearing in the card name or in the Processing Profile column when you view folders in the List Layout.
You can apply a video profile to a folder from within the Tools menu or if you are in the folder, from the Folder Settings. This section describes how to apply video profiles to folders both ways.
Folders that have a processing profile already assigned to it are indicated by the display of the profile's name directly below the folder name.
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Tap/click Apply Processing Profile to Folder(s) and select the folder or multiple folders you want use to receive the newly uploaded assets and tap/click Done. Folders that have a processing profile already assigned to it are indicated by the display of the profile's name directly below the folder name.
In addition to applying a profile to a folder, you can also apply one globally so that any content uploaded into AEM assets in any folder has the selected profile applied.
To apply a profile globally, do one of the following:
When you remove a video profile from a folder, any subfolders automatically inherit the removal of the profile from its parent folder. However, any processing of files that has occurred within the folders remains intact.
You can remove a video profile from a folder from within the Tools menu or if you are in the folder, from the Folder Settings. This section describes how to remove video profiles from folders both ways.
When you assign a video profile to a folder, any subfolders automatically inherit the profile from its parent folder. This means that you can assign only one video profile to a folder. As such, consider carefully the folder structure of where you upload, store, use, and archive assets.
If you assigned a different video profile to a folder, the new profile overrides the previous profile. The previously existing folder assets remain unchanged. The new profile is applied on the assets that are added to the folder later.
Folders that have a profile assigned to it are indicated in the user interface by the name of the profile appearing in the card name or in the Processing Profile column when you view folders in the List Layout.
You can apply a video profile to a folder from within the Tools menu or if you are in the folder, from the Folder Settings. This section describes how to apply video profiles to folders both ways.
Folders that have a processing profile already assigned to it are indicated by the display of the profile's name directly below the folder name.
-
Tap/click Apply Processing Profile to Folder(s) and select the folder or multiple folders you want use to receive the newly uploaded assets and tap/click Done. Folders that have a processing profile already assigned to it are indicated by the display of the profile's name directly below the folder name.
When you remove a video profile from a folder, any subfolders automatically inherit the removal of the profile from its parent folder. However, any processing of files that has occurred within the folders remains intact.
You can remove a video profile from a folder from within the Tools menu or if you are in the folder, from the Folder Settings. This section describes how to remove video profiles from folders both ways.
