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nablet HEVC AMA Plug-in

nablet Support Team
  • Updated

Description

The nablet HEVC AMA Plug-in allows you to link, play and edit HEVC/H.265 video in MP4 or MOV container via AMA in Avid editing products. It supports processing footage in the video sub-sampling formats 4:2:0 and 4:2:2 at 8 and 10 bits. AAC and PCM audio are supported.

The nablet HEVC AMA Plug-in reads the time code and interprets most of the important meta data when this is encapsulated in the media. Furthermore it detects BT.2020, HLG and other HDR capture gamma as well as Sony Slog in HEVC shots so that Media Composer can automatically assign a color transformation that matches the project color space.

Furthermore the nablet HEVC AMA Plug-in allows to work with Sony XAVC HS proxies.

Evaluation

The downloaded copy of the nablet HEVC AMA Plug-in will run in demo mode. A nablet logo will be printed into the decoded images but otherwise the plug-in is fully functional.

Follow the instructions here to purchase a license and how to unlock the plug-in to make the logo disappear.

After the plug-in was unlocked by a license, you can continue to use the clips that were previously linked in demo mode. You do not need to re-link them. The logo will disappear after the key has been validated by the plug-in. However, transcodings and video mix-downs have to be re-done since they have been encoded with the logo in the source image.

Requirements

Supported Avid Products

  • Avid Media Composer from v8.6 to latest releases.

Supported Operating Systems

Windows

  • Windows 11
  • Windows 10 64-bit

Mac

minimum Version

  • Intel CPU: macOS 10.15  (Catalina)
  • Apple Silicon CPU: macOS 11.00  (Big Sur)

Hardware Requirements

Decoding HEVC is a challenge for a computer system and will be most satisfying on modern hardware.

For best performance, on Windows systems the computer should be equipped with an NVIDIA or AMD GPU or an Intel CPU with Quick Sync Video feature, which support decoding of HEVC footage. An Intel processor with Quick Sync Video starting from Skylake family is suitable (Skylake fully accelerates 8 bit and partially accelerates 10 bit, later generations fully accelerate 8 and 10 bit). For the capabilities of your external GPU please check the manufacturers specification.

Minimum required GPU driver versions:

NVIDIA:            470.0

AMD:               20.7.1

Intel Iris:          26.20.100.8141

On Windows systems hardware accelerated decoding of 4:2:2 footage is currently only supported by 12th generation or later Intel GPUs. On any other system it will be processed by a software decoder.

On Mac systems HEVC decoding is supported through the Apple Video Toolbox API and performance depends on the systems hardware configuration.

Version History

What's new in version 2026.5?

  • Add support for highres 32bit float audio embedded in Sony XAVC HS MP4 file or from external WAVE file in Sony volume.
  • AMA Plugin Manager: Add control to set highres audio preferences.
  • Fix problem to detect validity of legacy license keys files.
  • Add support for educational licenses.

What's new in version 2026.2?

  • Fix linking iPhone clips with APAC audio track (only the AAC audio track will be linked).
  • Fix playback errors on macOS which occurred after Apple Pro Video Formats update or update to macOS 2026.2.
  • AMA Plugin Manager: Add control to disable hardware accelerated decoding on macOS.
  • AMA Plugin Manager: Fix invisible panels and controls when macOS is set to dark mode.

What's new in version 2025.11?

  • Global settings for decoding, image processing and license management can now be made via the nablet AMA Plugin Manager application.
  • New licensing model for convenient activation, de-activation and re-activation on different machine via the AMA Plugin Manager application.
  • Hardware accelerated 4:2:2 video decoding on GPUs with Nvidia Blackwell architecture.
  • Support selection of M4ROOT or PXROOT folders in Sony volume in order to allow convenient handling of combined volumes of XAVC – XAVC HS or similar.
  • New versioning scheme with first digits as YYYY.MM of the release date for better overview.

What's new in version 1.7.0?

  • Supports Apple Silicon (ARM) CPU on Mac.
  • Updated components on Windows and Mac version in order to support Apple Silicon.

What's new in version 1.6.0?

  • Processes application of Sony embedded LUT and CineEI on a supported GPU (OpenCL, Metal) to reduce CPU load.

What's new in version 1.5.1?

  • Fix video sample loss or image distortion upon fast scrubbing on macOS.
  • Fix possible decoder hangup on Intel GPU with latest drivers (v101.5522).

What's new in version 1.5.0?

  • Extended ISO range for EI processing.
  • Improvements on hardware accelerated decoding.
  • Approved for macOS 14, Sonoma.

What's new in version 1.4.1?

  • Fix linking failures of certain media.
  • Fix incorrect timecode on MOV files.

What's new in version 1.4.0?

  • Changed support for embedded LUT in Sony XAVC HS clips to a more user friendly and convenient workflow.
  • Added control to modify exposure of XAVC HS clips in Source Settings to support the Sony Cine EI workflow

What's new in version 1.3.0?

  • Support for embedded LUTs in Sony XAVC HS clips.

Try before you buy

Before you purchase a license for this product, please evaluate the plug-in in demo mode to verify that it fits your needs. Try whether your system is suitable for a sufficient workflow and make sure that the footage which you need to edit is supported.

Installation Procedure

Prerequisites

You cannot install the AMA Plug-ins while the editing application background services are running. Make sure you stop the services before installing AMA Plug-Ins. The stop/start background services icon is on the Media Composer menu bar (Macintosh) or taskbar (Windows). Once you installed the new AMA plug-in, restart the services. See “Starting and Stopping Avid Background Services” in the Media Composer Help.

Install Instructions Windows:

  1. Download the installer package “nablet_HEVC_Plugin_Setup_Win_2025.11.0.zip” and unpack it.
  2. Double click “nablet_HEVC_Plugin_Setup_Win_2025.11.0.exe” to run the installation.
  3. Follow the instructions provided by the installer. You must read and accept to the End User License. If you already own a license key file pass it's path when asked. If you used a temporary key file which you received for test purposes you can update it now with the key file you purchased.
  4. During the installation any previous version of the nablet HEVC plug-in will be updated.
  5. Additionally the nablet AMA Plugin Manager application will be installed or updated where you can manage licenses, configure plugin settings and open the user manual.

Uninstall Instructions Windows:

  1. Open Windows Control Panel and launch “Programs and Features”.
  2. Select “nablet HEVC Plug-In” and then select Uninstall.
  3. Next, select Yes to confirm the removal.
  4. The nablet HEVC Plug-in and a legacy license key file if present are now removed.
  5. Do not uninstall the nablet AMA Plugin Manager as long as you have other nablet plugins installed.

Install Instructions Mac:

  1. Download the installer package “nablet_HEVC_AMA_Plugin_Setup_Mac_2025.11.0.zip” and unpack it.
  2. Double-click “nablet_HEVC_AMA_Plugin_Setup_Mac_2025.11.0.dmg” to mount the image.
  3. A folder with “nablet_HEVC_AMA_Plugin_Setup_Mac_2025.11.0.pkg” opens.
  4. Launch “nablet_HEVC_AMA_Plugin_Setup_Mac_2025.11.0.pkg” to run the installation.
  5. Follow the instructions provided by the Installer application. You must read and accept to the End User License.  If you already own a license key file pass it's path when asked. If you used a temporary key file which you received for test purposes you can update it now with the key file you purchased.
  6. During the installation any previous version of the nablet HEVC plug-in will be updated.
  7. Additionally the nablet AMA Plugin Manager application will be installed or updated where you can manage licenses, configure plugin settings and open the user manual. It is located under “/Applications/nablet AMA Plugins”.

Uninstall Instructions Mac:

  1. Locate the directory “Library/Application Support/Avid/AVX2_Plug-ins/AMA/nablet”.
  2. Delete the nablet_MVP_MSP_HEVC.avx file.

       4.   If present, delete the legacy license key file 'nablet_HEVC_Plugin_my_name.key'.

  1. Empty the Trash to completely erase the files from the system.
  2. Uninstall the nablet AMA Plugin Manager only if you have no other nablet AMA plugins installed. Locate “Applications/nablet AMA Plugin Manager” and delete the whole folder with all it's contents.

Verifying the Plug-in Version

After installation the “nablet HEVC Plug-in”will be available to Avid Editing products. To confirm whether the plug-in was properly installed and verify the version follow the steps below:

  1. In Media Composer's project window hit the [Info] button
  2. A  list starting with version and license information for Media Composer will appear.
  3. Scroll down to find the AMA Plugin Info.
  4. Confirm that the “nablet HEVC Plug-in” is listed and the version is 2025.11.0

Evaluation

Without a license the plugin runs in demo mode. It will be fully functional, but a logo is imprinted into any decoded picture. This allows you to evaluate all features of the plugin without limitation and to find out whether it fits the needs of your workflow before you purchase a license.

Licenses

Starting with version 2025.11 this plugin supports a new, more flexible model for single and multi-seat licenses. Seats can be activated and de-activated and be re-activated on a different machine by means of an activation code. License management can be conveniently done via the nablet AMA Plugin Manager application that now installs with this and any future version of the plugin. A license will be valid for one year starting from first activation, but can be extended.

The new licenses cannot be used on versions of the plugin prior to version 2025.11.

Whether legacy license files (.key) purchased for earlier version can be used on the new version 2025.11 and later depends on their creation date. License key files purchased in 2025 will expire End of 2027, those purchased in 2024 will expire End of 2026, all others expire End of 2025.

License Activation

After the installation of the plugin run the nablet AMA Plugin Manager app. It will show each installed nablet plugin on an own tab. You can activate and reactivate the license by means of an activation code there and also pass or remove a legacy license key file if it is not expired*. Please follow the instructions on the user manual of the nablet AMA Plugin Manager app.

*Please note that legacy license files, depending on their creation date will expire sooner or later for this plugin version and future updates. For versions of the plugin prior to v 2025.11 you can continue to use the license key file.

The license must be used on a single computer only. You may also purchase multi seat licenses.

Once the license has been validated by the plug-in, the nablet logo will disappear from the linked clips. Now redo any transcodings, consolidations and video mix downs which have been done during the evaluation period and which show the logo.

Operation Procedure

Linking single or multiple clips Linking to HEVC files on Media Composer 8.6 and later

  1. Select the desired destination bin in the project.
  2. From the menu bar Select File->Input->Source Browser.
  3. When in the Source Browser dialog, make sure that 'Link' is selected, not 'Import'
  4. Navigate to the HECV file(s) to be linked.
  5. Media Composer will not assign the plug-in automatically. Select and Right click the desired file(s) and select “Link with -> nablet HEVC”.
  6. Hit the Link button on the bottom right.

Linking to HEVC files on Media Composer 8.5 and earlier

  1. Select the desired destination bin in the project. 
  2. From the menu bar Select File> AMA Link… (“Link to Media…” if using Avid MC 8.4/8.5).
  3. Media Composer will not assign the plug-in automatically. From the Files of Type pull down menu select “nablet HEVC (*.mov, *.mp4)”.
  4. Select the  file(s) to be linked.
  5. Hit the Open button on the bottom right.

Linking whole recording media content at once

Some cameras write clips into a specified folder structure on the recording media, where also companion meta data files may be stored. In a typical workflow you will copy the complete contents of each recording media, including all sub-folders and meta data files, into a new parent directory on your local storage. This parent directory's name may contain the shot location, card number etc. to later easily identify the footage. If the camera manufacturers folder structure is supported by the plugin, you can now link the whole media contents at once by linking the parent folder. An example are XAVC HS recordings by some Sony cameras where the volumes root folder is named M4ROOT.

Linking to an HEVC Volume on Media Composer 8.6 and later

  1. Select the desired destination bin in the project.
  2. From the menu bar Select File>Input>Source Browser.
  3. When in the Source Browser dialog, make sure that 'Link' is selected, not 'Import'.
  4. Navigate to the desired volume.
  5. Select the parent folder above the volumes root folder.
  6. Hit Link button on the bottom right. Media Composer will choose the nablet HEVC plug-in automatically.

Linking  to an HEVC Volume on Media Composer 8.5 and earlier

  1. Select the desired destination bin in the project.
  2. From the menu bar Select File> AMA Link… (“Link to Media…” if using Avid MC 8.4).
  3. Media Composer will not assign the plug-in automatically. From the Files of Type pull down

menu select “nablet HEVC (Folder)”.

  1. Select the parent folder above the volumes root folder..
  2. Select Open.

If a Sony volume is a combined volume from a shot with simultaneous recording which consists of XAVC and XAVC HS volumes, only one of them will be linked, the other one will be skipped. To overcome this, select the XDROOT or M4ROOT folder to link them separately. 

Transcoding

Do not attempt to transcode a linked clip from within Media Composer's Source Browser as offered when you tried to Import instead to Link. Always link the footage as described above. When done navigate to the bin with linked clips, select the desired clips, right click and select

“Consolidate/Transcode”. In the Consolidate/Transcode dialog select Transcode on the top left. For details about the further settings please refer to the Media Composer manual. Once the transcoding is completed the transcoded file(s) will appear next to the linked source clip(s) in the bin.

Auto Mount

When you insert the recording media into a card reader which is connected to your PC or when you connect your camera to your PC via USB while Media Composer is running, it may detect the volume and automatically link the clips into a new bin. While this procedure seems to be convenient, please keep in mind that the footage still remains on the recording media. Once the media is removed or disconnected the footage will appear as offline.

Use this way of linking only when you want to immediately transcode the footage for editing after linking.

Performance problems during linking with Source Browser of Media Composer 8.6 and later

In some cases the Media Composer Source Browser may be very slow and sometimes behave erratic when you attempt to link single clips rather than a whole volume. If you frequently face issues with the Source Browser, an option is to use the legacy link dialog instead. This dialog is still available under

Media Composer 8.6 and later, but it is hidden. To make it available persistently select Tools → Console and in the consoles command line type ToggleHideLinkMenus and hit Enter. (To hide the dialog again repeat the command). Now proceed linking clips and volumes as described for Media Composer 8.5.

Source Settings, Color Transformations and Embedded LUTs

In order to view the Source Settings window, you must right click a clip in a bin and select Source settings… There are three tabs in this window, Linked Plug-in, Color Encoding and FrameFlex that affect the image appearance.

The Color Encoding tab allows you to add and remove LUT tables, which will change the visual look of the image an which can transform the clips color space to the project color space.

The Frameflex tab allows you to change the dimension and framing of the image.

The Linked-Plugin tab allows to change the exposure of the clip. Application of an embedded LUT, which is explained later, can be enabled here as well.

Note that exposure control is only available for Sony XAVC-HS clips shot with Slog3 capture gamma. Initially the value for Exposure that was found in the clips meta data is used. The Exposure can be adjusted in range from ISO 80 to ISO 10000 in steps of 1/3 of a stop.

To reset the custom exposure setting to the value at recording time choose Clip Meta Data settings above. To reset them to generic defaults choose the Default settings above.

Note:

On some versions of Media Composer the first attempt to change a value does not take effect. To overcome this, toggle a setting one time, e.g. switch between Clip Meta Data and Default and back. After that any further changes will take effect.

The image preview on the Linked Plug-in tab shows the image in the format before any Color

Transformation LUTs and Look LUTs have been applied on the Color Encoding tab. Switch to the Color Encoding tab to view the final effect of your custom settings after the LUTs have been applied and thus how the image will appear in further processing, or, if the clip is opened in the Source Monitor, use full screen display on a secondary monitor to view the final image while you change settings.

Managing Color Adapters

When you link footage whose Capture-Gamma or Transfer-Characteristic does not match the project color space, for example a clip with Sony S-Log3.Cine into an BT.709 project, a color transformation is needed to correctly display the pictures.

Media Composer ships with a variety of LUTs for color transformations, including those for Sony S-Log color spaces. Automatic insertion of a matching color transformation upon linking can be enabled in the Color Management Settings. They can be reached either via File->Settings->User tab or at the Color Encoding tab in the Source Settings dialog.

Open the Source Settings dialog of the linked clip to see the current color transformation.

If automatic insertion of a color transformation is disabled in the Color Management Settings, or if the clip color space matches the project color space, the Color transformations list will be empty. If color spaces don't match, you can now insert a color transformation manually in two ways:

Under Color Adapters hit the Auto button which will cause Media Composer to insert the required transformation automatically now.

Or select the desired Color Adapter from either the Generic or User installed LUTs type.

Look LUTs and custom Color Transformation LUTs

If you have a Look LUT, a LUT that gives the recorded video a creative look, or a custom color space

transformation LUT that you want to insert, first you need to install that LUT via the Color Management Settings dialog.

For details please see the Media Composer user manual. A user installed LUT can be inserted in the same way than manually inserting a color adapter. Select it from the User Installed LUTs Color Adapter type. 

Make sure to position a Look LUT before any color transformation. If you added a Look LUT after a color transformation was added automatically or manually, you can easily drag the Look LUT upwards to the top position.

Sony XAVC HS Embedded LUTs

Some Sony XAVC HS clips may carry an embedded LUT. This can be a creative LUT to apply a specific look to the recorded footage or a color transformation LUT for example for conversion from Slog3.Cine to BT.709 or they can even be a combination of both. When an embedded LUT is available you will find the additional checkbox on the Linked Plug-in tab.

Hover with the mouse over the checkbox to get information about the name of the LUT.  To use this LUT enable it's application with this checkbox. Also for this, on some Media Composer versions you may need to toggle the setting once to see the application of the LUT taking effect on the display window.

You can also check the availability of an embedded LUT in the bin's Monitoring Descriptions column.

The name prefix “EMB1” indicates that it is an embedded LUT.

If the LUT is a pure creative LUT, after you enabled the application of it the color transformations on the Color Encoding tab can be kept as they are. However, if the LUT contains a color space transformation, the color transformation on the Color Encoding tab must be deleted. Otherwise you will get a duplicate color transformation which results in a bad image with wrong colors. Switch to the Color Encoding tab, select the items in the Color transformations list and delete them.

If you know in advance that the footage has an embedded color transformation LUT and that you want to use it, disable the automatic insertion of color transformation in the Color Management Settings before you start linking. Use File->Settings->User->Color Management or hit the Color Management Settings button on the Source Settings Color Encoding tab to change the behavior.

Of course the color transformation of the embedded LUT must match the color space of your editing project. For example you must not use a LUT with a target transformation to BT.709 in a project with Slog3 or HLG color space to avoid wrong colors.

Unlike the settings on the other Source Settings tabs, unfortunately Media Composer does not support to apply the settings on the Linked Plug-in tab to multiple selected clips. So you must enable and disable the application of an embedded LUT for each clip individually.

Configuring Plugin Features at the nablet AMA Plugin Manager

The nablet AMA Plugin Manager app which has been installed along with this plugin allows to configure some global plugin settings which cannot be done on the limited Source Settings->LinkedPlugin user interface under the Avid host. Run the nablet AMA Plugin Manager and choose the HEVC tab.

On Windows OS you find a button Configure Decoder which raises a dialog where you can specify which kind of decoder is being used. By default the plug-in will decide automatically which decoder it uses. It prefers the accelerated HEVC decoder of a discrete GPU if that is available

The behavior of the plug-in to automatically choose the best decoder should be sufficient in most cases and you won't need to intervene. But there may be a few cases where it is good to have means to override the plug-in's default behavior. This can be when a specific type of footage is not properly decoded on the GPU. Or, this is probably a rare case, the decoder of the discrete GPU is less powerful than the Intel Quick Sync Video decoder of your CPU, or even your CPU is so powerful that it outperforms the hardware accelerated decoders when using the software decoder.

On macOS the decoder is managed automatically. For best performance by default hardware accelerated decoding will be used. However there are known issues with hardware accelerated decoding on some versions of macOS. If you are facing playback problems you can disable hardware accelerated decoding by un-checking the option Use hardware accelerated video decoding.

When an embedded LUT or Cine EI has to be applied on Sony XAVC HS clips, by default a GPU will be used for processing the image. If there is any issue with the GPU or its drivers you can force the plugin to do the processing on the CPU. Uncheck the option Use GPU for LUT and Cine EI processing.

Some Sony cameras which record XAVC HS are able to record high resolution 32 bit Float PCM audio. The highres audio will be stored in WAVE files, but can also be embedded in the MP4 file. Alternatively, while the WAVE file is always of 32 bit float format, the MP4 file can hold 16 or 24 bit Integer PCM instead. WAVE files of course are only available in complete unmodified XAVC S volumes. If highres audio is detected in a clip and a WAVE file is present, the plugin will prefer to link the 32 bit float audio tracks from the WAVE file. You can force it to only link the MP4 embedded audio by unchecking the option Use HighRes 32 Bit Float PCM audio from Wave Files if existing.

Change the Audio Preference before linking the clips. If you change it after linking any XAVC S clips you must link them again.

Avid Playback Settings

The playback quality in the Avid applications can be configured using the Video Quality Menu in the Timeline window. When the Avid Video Quality menu is set to Full Quality the full 8K, 6K, 4K or 2K image is being decoded. At a Draft Quality setting an image of 1/2 resolution is being decoded and at the Best Performance option an image of 1/4 resolution is decoded.

For a fluent playback it is recommended to choose Draft or Best Performance mode. To view images in best Quality choose Full Quality mode.

Working with Sony Proxies

Some Sony cameras can simultaneously record low resolution HEVC or AVC encoded proxy files besides the high resolution AVC or HEVC encoded main AV stream. Such proxy files are wrapped in MP4 container in same style as XAVC HS and XAVC S clips.

AVC or HEVC proxies may reside either on the same recording media in the “Sub” folder or at a separate media. When the proxies are stored on a separate media this media has a similar folder structure as XAVC HS and XAVC S, but the root folder is named PXROOT rather than M4ROOT, already indicating that the recorded footage is of low resolution.

Note: For linking Sony AVC proxy files in MP4 container the nablet XAVC S AMA Plug-in v2.1.1 or later needs to be installed. Linking of Sony HEVC proxy clips is supported by this plugin directly.

To link high resolution XAVC (MXF) files the nablet XAVC XDCAM plugin is required to be installed. Linking of XAVC AVC (MP4) high resolution footage is supported by the nablet XAVC S plugin.

To work with proxy files for editing you must link the high resolution footage as well as the low resolution proxy files. Proceed as described below to link the clips and to become able to switch between high resolution and proxy editing.

  1. Link the XAVC HS (MP4) high resolution footage by means of the methods described earlier in this manual or the XAVC (MXF) footage by means of the methods described in the manual of the nablet XAVC XDCAM plugin or the XAVC S footage by means of the methods described in the manual of the nablet XAVC S plugin. Either link the whole volume or link selected clips from the “Clip” folder.
  2. In case the proxy files are HEVC encoded:

If the proxy clips reside on a separate media, link the whole media by selecting the parent folder above PXROOT, or link selected clips by Right Click->Link with->nablet HEVC.

If the proxy clips were recorded to the same media as the high resolution clips, navigate to the “Sub” folder and link all or selected clips by Right Click->Link with->nablet HEVC.

  1. In case the proxy files are AVC encoded:

If the proxy clips reside on a separate media, link the whole media by selecting the parent folder above PXROOT, or link selected clips by Right Click->Link with->nablet XAVC S.

If the proxy clips were recorded to the same media as the high resolution clips, navigate to the

“Sub” folder and link all or selected clips by Right Click->Link with->nablet XAVC S

You may link high resolution clips and proxy clips into the same bin but it is recommended to link them into separate bins for a better overview.

Number of High Resolution audio tracks vs. number of Proxy audio tracks

Important! Sometimes the AVC proxy clips have less audio tracks than the high resolution clips. So, special care has to be taken to be able to edit with all audio tracks. If you would fill and edit your timeline directly with the linked proxy clips, you may work for example with 2 audio tracks only while the high resolution clips have 4 or 8 audio tracks. Relinking the sequence to high resolution later will not add the missing audio tracks!

Beginning with this version version 1.2.2 of the nablet HEVC plugin and version 2.1.1 of the nablet XAVC S plugin, these plugins will detect the number of high resolution audio tracks and will add silent dummy tracks for the linked proxy clips to match the number of high resolution audio tracks, so that your workflow becomes easier.

This detection will happen always when high resolution and proxy clips reside on the same media volume.

When high resolution and proxy clips were recorded on separate media it depends on the proxy volumes metadata version whether the number of high resolution is signaled in the clips companion XML file. If it is signaled, this will let the XAVC S plugin know the number of high resolution audio tracks and thus how many dummy tracks it will have to add. If it is not there the XAVC S plugin cannot add dummy tracks upon linking and you have to choose a bit more complex workflow.

You can see the number of audio tracks after linking when the 'Tracks' column on the bin to where you linked the clips is enabled.

So, different workflows are required depending on whether you have to work with a different number of audio tracks or an equal one. Please see the instructions on the following pages.

Note:

When you have proxy or high resolution clips with varying number of audio tracks, e.g. some clips have 4 channels, some clips have 8 channels, and the first clip you add to new sequence has less channels than others, then Media Composer will only automatically create this number of audio tracks. When you place a clip with higher number of channel later on the sequence, no additional audio tracks will be created and not all audio tracks of that new clip will be present.

Make sure your sequence has enough audio tracks and manually add additional audio tracks to the sequence before you place clips with higher number of tracks.

If the number of high resolution audio tracks is equal to the number of audio tracks shown for the linked proxy clips in the bin columns:

Fill and edit the timeline with the proxy clips. When you are done with editing select the sequence in it's bin and raise the Relink dialog by Right Click->Relink...to relink the sequence back to high resolution:

All high resolution and proxy clips shall have been linked already so that they can be located in the media database by the Relink process.

High resolution and proxy files typically carry the same Source File ID. This is used by the host to identify the matching source clips for relinking.

As the format and image dimensions of high resolution and proxy clips are different by nature make sure to allow Relink to: Any Video Format. Then Select Highest Quality as Relink method.

In some cases the high resolution clips and the proxies have different frame rates. Make sure to enable Allow relink across rates, otherwise only clips with the same frame rate get relinked.

Check Create new sequence if you want the selected sequence to be relinked into a copy.

To switch a sequence back to proxy resolution proceed as above but select Relink Method: Most Compressed.

In some cases, when the high resolution clips are of AVC format and the proxy clips are of HEVC format, the above relink methods may not work as expected. When relink method “Most Compressed” is chosen the high resolution clips get linked and vice versa.

A recommended workflow here is to use Relink to “Video format of current project only...” to relink to high resolution:

Where the project  dimensions and framerate must match the source material parameters.

To link back to proxy use Relink to “Any HD video format” or “Any SD video format”, depending on the resolution of the proxy clips:

If the number of high resolution audio tracks is higher than the number of audio tracks shown for the linked proxy clips in the bin columns:

You need to relink the high resolution clips to low resolution once before you start editing. But only the video track!

1.   Select all high resolution clips in their bin and do Right Click->Relink... to raise the Relink dialog and configure the relink process:

As said earlier all high resolution and proxy clips shall have been linked already so that they can be located in the media database.

High resolution and proxy files typically carry the same Source File ID. This is used by the host to identify the matching source clips for relinking.

As the format and image dimensions of high resolution and proxy clips are different by nature make sure to allow Relink to: Any Video Format. Select Most compressed as Relink method.

It is important to select only the Video track to be relinked and keep the audio tracks as high resolution! This way the relinked clips will still refer to all high resolution audio tracks.

In some cases the high resolution clips and the proxies have different frame rates. Make sure to enable Allow relink across rates, otherwise only clips with the same frame rate get relinked.

  1. Now you may create the sequence and start editing by filling the timeline with the relinked clips from the high resolution bins. You will see that the video track appears as low resolution but all high resolution audio tracks are available on the timeline.
  2. To relink a sequence with low resolution video source back to high resolution for export, high quality rendering and preview, select the sequence in it's bin and raise the Relink dialog by Right Click->Relink...to relink the sequence:

To switch a sequence back to proxy resolution proceed as above but select Relink Method: Most Compressed.

On some macOS versions relinking the sequence might not work as shown above. The video track on the timeline may stay at the low resolution.

Instead select the high resolution clips in their bin again and proceed as above but select Relink method: Highest Quality. Again only relink the Video track!

The video track on the sequence will change its resolution too.

To relink a high resolution sequence back to proxy format, proceed as above but select Relink method: Most Compressed.

Note:

If you had linked the HEVC proxy clips before with the nablet HEVC plugin earlier than v 1.2.1  or the AVC proxy clips with  the nablet XAVC S plugin earlier than v2.1.0 or had linked them with Media Composers builtin plugins, the clips will not be detected by the Relink process.

You must remove the clips from the project, clean the media data base first and then link the proxy clips as well as the high resolution clips.

Known Issues and Limitations

  • HEVC video files with variable frame rate, as for example recorded by some smartphones, are not fully supported. Such clips can be linked and played, but longer clips may lose audio synchronization. Transcode longer clips to constant frame rate by third party tools before linking. Note that in professional video production frames of constant duration are expected. It is not recommended to use devices which record with variable frame rate for shooting interviews or other scenes where audio/video synchronization is important.
  • On systems with no GPU or with a GPU that does not support decoding a specific type of HEVC video the plug-in will fall back to software decoding on CPU. A powerful CPU is required for a smooth playback.
  • For realtime playback of HEVC video set the Avid’s NLE Video Playback Quality setting to Draft or Best Performance.
  • Depending on the performance of the GPU or CPU and the parameters of the HEVC video stream a realtime playback may not be possible, but transcoding to a proxy format or DNxHR intermediate codec after linking is an option to enable smooth editing.
  • On AMD GPUs with driver sets prior to 2020.7.1 some footage will not be properly decoded and show color shifts. Please update drivers to 2020.7.1 or later
  • Decoding of footage with 4:2:2 chroma sub-sampling is not supported under macOS 10.13. Please upgrade to macOS 10.14 or a later version.
  • After transcoding a clip or after performing a video mix down, which always requests the plugin to provide frames in highest quality, some versions of Media Composer will not reset to the desired lower Video Playback Quality when playing back the source file or timeline. Toggle the Video Quality setting once when you encounter a performance loss during playback.

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