Bidirectional animation converter between Skyrim and Fallout 4

[dagobaking]

Bidirectional animation converter between Skyrim and Fallout 4

View File

---

## IMPORTANT: Respect Animation Authors
 

**DO NOT use this tool to republish someone else's animations without their explicit permission.**

This means nowhere — not on LoversLab, Nexus, sites in any language, Google Drive, MEGA, Discord servers, or anywhere else. If the original animator did not give you permission to convert and redistribute their work, then don't. It doesn't matter if you converted the format — the creative work is theirs, not yours.

If someone is found republishing others' work without permission, I will take this tool down and only share future improvements privately. Don't be that person.

**If you want to convert someone's animations for personal use, go ahead. If you want to publish a converted pack, get the author's permission first.**

### Skyrim to FO4 Converter
- Full spline decompression and re-compression pipeline
- 62-bone skeleton remapping (XPMSE to ZeX Extended)
- Rest-pose correction with custom idle pose support (`rotation_base = custom`)
- Handles Skyrim LE tagfile XML and SE binary HKX (auto-detected)
- Per-chain rotation amplitude adjustment
- Worldspace position offset for actor alignment
- Blender Control-Rig import via JSON export
- Batch pipeline with ESP and AAF XML generation

### FO4 to Skyrim Converter (Beta)
- Reverse retargeting from FO4 skeleton back to Skyrim XPMSE
- Outputs Skyrim LE tagfile XML (usable as .hkx directly)
- Batch mode with FNIS list file generation
- Not yet tested in-game — roundtrip verification passes (most bones 0.00° error)

### General
- `convertToFO4.bat` and `convertToSkyrim.bat` — drag-and-drop batch wrappers
- Annotation tracks preserved from source animations

---

• Submitter
  dagobaking
• Submitted
  03/11/26
• Category
  Other
• Requirements
  ### Python 3
  Any recent Python 3 installation (3.8+). No third-party packages needed — uses only standard library modules (`xml.etree.ElementTree`, `struct`, `math`, etc.).
  
  ### Java Runtime
  Required for `hkxpack-cli.jar` which packs the final XML into binary HKX.
  
  - Java 8 or newer
  - Download: https://www.java.com/en/download/
  
  ### hkxpack (required download)
  HKX packer for Fallout 4 format. Converts the generated XML into binary HKX.
  
  - Download the latest release from: https://github.com/Dexesttp/hkxpack/releases
  - Place `hkxpack-cli.jar` and `hkxpack-core.jar` in the project folder
  
  ### hkxc.exe (required for SE animations)
  This is `serde-hkx-cli` which converts Skyrim SE binary HKX to XML. Only needed if converting **Skyrim SE** binary animations. Skyrim LE tagfile animations do not need this.
  
  - Download from: https://www.nexusmods.com/skyrimspecialedition/mods/126214
  - Place `hkxc.exe` in the project folder
  
  ### Blender 3.x+ (optional, for Blender import)
  Required only if you want to import converted animations onto an FO4 Control-Rig in Blender for preview or further editing. See blender-import-to-fo4-control-rig on AAF Discord server.

 

[dagobaking]

Some side notes:

I made a custom rest pose that puts the FO4 skeleton in as close to the Skyrim rest pose as I could get it. That helped alignment quite a lot. But, its still not perfect. The two skeletons just have differences, especially in the arms/hands.

 

That said, there are two main paths I see for improving alignment:

A) Maxie's SAM Former mod: https://www.nexusmods.com/fallout4/mods/66269

 

B) There is a Blender script included with this tool that adds an animation to the Blender rig I made (on AAF Discord). From there, you can adjust the animation as needed and re-compile the hkx.

 

Someone please let me know what the FO4-to-Skyrim animations look like. I can adjust with some feedback. For now, I just aligned them 1:1

 

[Sirgod]

This is going to be an amazing tool! Now I need to go and get in contact with about 6 animation makers.

[Allnarta]

I made testing animations pack port (forgive me Anub I am not going to release it anyway), and I can say that results in general are very solid. Arms are indeed misaligned for all animations though, which should be fixable by proper SAM/Blender edits without too much trouble. Also, AAF files do not generate _positionData xml, so it has to be created by hand.

[Holylokki]

7 hours ago, Allnarta said:

Also, AAF files do not generate _positionData xml, so it has to be created by hand.

Most likely because for AAF v1.1.2+ the positionData file is not required.

[Allnarta]

9 minutes ago, Holylokki said:

Most likely because for AAF v1.1.2+ the positionData file is not required.

 

Most likely I have some earlier version installed (1.1.1 I assume), so likely it's a thing.

[NCK30]

Thanks to the author. Proper guidelines. Will be following.

[dagobaking]

18 hours ago, Allnarta said:

I made testing animations pack port (forgive me Anub I am not going to release it anyway), and I can say that results in general are very solid. Arms are indeed misaligned for all animations though, which should be fixable by proper SAM/Blender edits without too much trouble. Also, AAF files do not generate _positionData xml, so it has to be created by hand.

 

Thank you for using!

 

As others mention, it doesn't generate positionData because in version 1.1.2+ its only needed for animationGroupData and positionTreeData. And in 1.5.0+ they are not needed at all.

[Cookiemonsta234]

Thanks for this! Is it possible that Starfield can have animations converted in the future? 

 

Also, can we show the animations like in screenshots, gifs, or videos to others for proof of concept reasons? Its technically not republishing the animations per se its just showcasing that they in fact work. A lot of animators who made the animations have left the scene and getting in contact with them is difficult if not impossible.

Edited March 17 by Cookiemonsta234

[dagobaking]

10 hours ago, Cookiemonsta234 said:

Thanks for this! Is it possible that Starfield can have animations converted in the future? 

 

I'll have to do a little digging to figure out how possible that is. Is there a community tool available that packs/unpacks the new hkx format that game uses?

 

10 hours ago, Cookiemonsta234 said:

Also, can we show the animations like in screenshots, gifs, or videos to others for proof of concept reasons? Its technically not republishing the animations per se its just showcasing that they in fact work. A lot of animators who made the animations have left the scene and getting in contact with them is difficult if not impossible.

 

This a good question. I'm not sure what the answer is. It even seemed to confuse ChatGPT.

It might be something that hasn't been tested legally before. So, it remains in a limbo depending on what the community tolerates.

 

Being in the middle, I can only advise steering toward caution and getting permission first. But, maybe someone else has a different view, knowledge on that one.

[Cookiemonsta234]

9 hours ago, dagobaking said:

I'll have to do a little digging to figure out how possible that is. Is there a community tool available that packs/unpacks the new hkx format that game uses?

 

 

I'm not sure I'll have to look around. 

 

9 hours ago, dagobaking said:

Being in the middle, I can only advise steering toward caution and getting permission first. But, maybe someone else has a different view, knowledge on that one.

 

I completely understand and respect your stance on not republishing others' animations without permission. That's absolutely the right approach.

However, I've noticed that this converter tool seems to be known only to a small group, and I think it could benefit the wider modding community if used responsibly. I'm not suggesting anyone republish converted animation packs quite the opposite.

 

What I'm wondering is this:

Would it be acceptable to create a detailed guide (like a PDF) or on a mod page that teaches people how to use your tool responsibly with specific animation packs? The guide would:

Link to your tool (giving you credit)

 

Explain where to find specific original animation packs that were already proven that that they can be converted (pointing to official Nexus/LoversLab pages, not providing direct downloads)

Show the animations in action as a proof of concept with gifs, screenshots, and videos to encourage users to convert animations. 

Provide step-by-step conversion instructions with example settings for that specific animation pack

Show how to integrate the results with AAF (XML examples, etc.)

Emphasize the ethical guidelines you've set that converted files are for personal use only and not for redistribution

Because apparently you do not need the consent of an animator to convert animations with the tool. Its only if you want to republish it.

Animation authors could be credited with a simple line like, All credits go to CEO, NCK30, Rohzima, Funnybizness, ZAZ, Zynisch, Anub, Sir Nibbles, Billyys, Leito, etc.... from here some animators already gave consent that their animation packs could be converted to a different game.

 

Here are others that uploaded converted animations from Skyrim LE to SE because animators said it was ok in their files tab https://www.loverslab.com/profile/143667-pfiffy/?tab=node_filestabprofile_filesTab    https://www.loverslab.com/profile/2695162-nomkaz/?tab=node_filestabprofile_filesTab

 

Can find more animations and mods here

https://www.loverslab.com/profile/143667-pfiffy/?tab=node_filestabprofile_filesTab

 

 

 

The goal would be to empower more people to create their own personal conversions, not to enable piracy or redistribution. Users would still need to download the original animations from the creators' official pages. But by having a few specific example packs it shouldn't be a problem.

Would this be acceptable to you? I want to make sure I respect your work and the original animators while helping more people access this knowledge. If others would like to do it this way too then that would make it easier for people who are not too technically savvy. 

Thanks for creating such a useful tool, and for caring about ethics in the modding community.

Edited March 17 by Cookiemonsta234

[NCK30]

I can only speak for myself. But showing pics and gifs would be alright with me.

 

Actually it would be fun to see what they look like in another game.

 

Edited March 17 by NCK30

[Cookiemonsta234]

On 3/11/2026 at 7:28 AM, Allnarta said:

I made testing animations pack port (forgive me Anub I am not going to release it anyway), and I can say that results in general are very solid. Arms are indeed misaligned for all animations though, which should be fixable by proper SAM/Blender edits without too much trouble. Also, AAF files do not generate _positionData xml, so it has to be created by hand.

 

See here Anub already gave consent that their animations could be converted to a different game. If you wanted to you could republish the converted animations that you made here for FO4 on LL because they gave consent already.

 

Edited March 17 by Cookiemonsta234

[Allnarta]

2 minutes ago, Cookiemonsta234 said:

 

See here Anub already gave consent that their animations could be converted to a different game. If you wanted to you could republish the converted animations that you did here for FO4 on LL.

 

 

That's great news actually, his animations are really solid and there's plenty of them.

 

Republishing as is would not make a lot of sense as most need arms adjusement, but having open permission is a very good thing.

Edited March 17 by Allnarta

[Cookiemonsta234]

36 minutes ago, Allnarta said:

Republishing as is would not make a lot of sense as most need arms adjusement, but having open permission is a very good thing.

 

Great! So other animators animations like zaz could be converted and republished if arm adjustment gets fixed because they gave permission for their animations to be republished already 

 

Edited March 17 by Cookiemonsta234

[dagobaking]

9 hours ago, Cookiemonsta234 said:

Would it be acceptable to create a detailed guide (like a PDF) or on a mod page that teaches people how to use your tool responsibly with specific animation packs?

 

Yeah. I think that would be helpful for sure. And, you don't really need a lot of permissions. Because, you only need to show one example, right?

 

Out of all the animators/packs around, it should be easy to get perms from at least one?

 

9 hours ago, Cookiemonsta234 said:

Show the animations in action as a proof of concept with gifs, screenshots, and videos to encourage users to convert animations. 

Provide step-by-step conversion instructions with example settings for that specific animation pack

Show how to integrate the results with AAF (XML examples, etc.)

 

To a degree. I don't think you need to make a whole catalogue of every pack/animation. You just need to show how to do the conversions with an example(s).

 

The original authors can make video catalogues, etc. for the originals. This is part of why permissions are important. Because the original authors may have something specific in mind about where and how their work is displayed.

 

9 hours ago, Cookiemonsta234 said:

The goal would be to empower more people to create their own personal conversions, not to enable piracy or redistribution. Users would still need to download the original animations from the creators' official pages. But by having a few specific example packs it shouldn't be a problem.

Would this be acceptable to you? I want to make sure I respect your work and the original animators while helping more people access this knowledge. If others would like to do it this way too then that would make it easier for people who are not too technically savvy. 

Thanks for creating such a useful tool, and for caring about ethics in the modding community.

 

Thank you for asking. Yes. I think its ok to make guides about how to use this tool provided that you have permissions for any work that is used in the examples. That should be pretty easy to get.

 

And I should give more credit out myself. For example, to @DexesTTP and SARDONYX7 for their hkx tools!

[Cookiemonsta234]

2 hours ago, dagobaking said:

Yeah. I think that would be helpful for sure. And, you don't really need a lot of permissions. Because, you only need to show one example, right?

 

Out of all the animators/packs around, it should be easy to get perms from at least one?

 

Why would you need permission for this? Its only an issue if someone tries to republish the animations without permission not explain how to convert them for personal use? I get the part about authors wanting to make video catalogues and if someone wanted to they could get that but is doesn't have to be required right? Especially if the authors are not around.

 

 

Edited March 17 by Cookiemonsta234

[dagobaking]

2 hours ago, Cookiemonsta234 said:

Why would you need permission for this? Its only an issue if someone tries to republish the animations without permission not explain how to convert them for personal use? I get the part about authors wanting to make video catalogues and if someone wanted to they could get that but is doesn't have to be required right? Especially if the authors are not around.

 

I feel that I've been pretty clear about my position on that.

 

Given that permissions seem available at least for examples, I'm not sure why this is still a question? It gives me the impression that the entire plan isn't being shared or that I'm being asked to give my blessing on questions I'm not authorized to answer.

[Cookiemonsta234]

2 hours ago, dagobaking said:

 

I feel that I've been pretty clear about my position on that.

 

Given that permissions seem available at least for examples, I'm not sure why this is still a question? It gives me the impression that the entire plan isn't being shared or that I'm being asked to give my blessing on questions I'm not authorized to answer.

 

Thanks for clarifying! I think I understand your position better now.

You're saying:

 

A guide teaching people how to use the converter is a good idea

But to make that guide concrete and useful, it needs to work through a real example

For that example, we should get permission from at least one animator to use their work as the demonstration

That way, the guide is ethical from the start and sets a good example for others

 

And my question about 'why need permission if it's just teaching' was missing the point. The permission isn't for the guide itself, but for using someone's actual animations as the example material. Even though we're not distributing the converted files, we'd still be showing their work in screenshots, describing their animation pack by name, and using it as the basis for instructions.

Is that right? If so, I completely agree. Finding one animator willing to give permission for an educational guide should be doable, and it would make the guide both ethical and practical. I totally misinterpreted that I apologize. 

Thanks for being patient with my questions I genuinely want to do this the right way.

Edited March 18 by Cookiemonsta234

[dagobaking]

Yep. That sounds right. It sounds like we just misinterpreted each other.

 

I look forward to seeing the guide!

[Cookiemonsta234]

On 3/17/2026 at 4:25 AM, dagobaking said:

I'll have to do a little digging to figure out how possible that is. Is there a community tool available that packs/unpacks the new hkx format that game uses?

 

 

Also regarding Starfield this just came out its a Blender addon for animation-related Starfield file formats

 

I am not sure if it is what you were referring to though https://www.nexusmods.com/starfield/mods/16184?tab=posts 

 

and here is something called CALUMI.Motion its an animation behavior graph editor to view and create .agx files. https://www.nexusmods.com/starfield/mods/16181 

 

This reddit post describes them all https://www.reddit.com/r/starfieldmods/comments/1rxlwyc/animation_tools_released/?share_id=rbw3o08NHM-1Xocjrn2wX&utm_content=1&utm_medium=android_app&utm_name=androidcss&utm_source=share&utm_term=1

 

 

I also saw that Starfield was getting a DLSS 5 update which uses AI to change the appearance of characters and the environment to make them look more "life-like" https://www.nvidia.com/en-us/geforce/news/dlss5-breakthrough-in-visual-fidelity-for-games/

Edited March 19 by Cookiemonsta234

[NCK30]

5 hours ago, Cookiemonsta234 said:

 

Also regarding Starfield this just came out its a Blender addon for animation-related Starfield file formats

 

I am not sure if it is what you were referring to though https://www.nexusmods.com/starfield/mods/16184?tab=posts 

 

and here is something called CALUMI.Motion its an animation behavior graph editor to view and create .agx files. https://www.nexusmods.com/starfield/mods/16181 

 

This reddit post describes them all https://www.reddit.com/r/starfieldmods/comments/1rxlwyc/animation_tools_released/?share_id=rbw3o08NHM-1Xocjrn2wX&utm_content=1&utm_medium=android_app&utm_name=androidcss&utm_source=share&utm_term=1

 

 

I also saw that Starfield was getting a DLSS 5 update which uses AI to change the appearance of characters and the environment to make them look more "life-like" https://www.nvidia.com/en-us/geforce/news/dlss5-breakthrough-in-visual-fidelity-for-games/

 

Don't You mean more fake AI looking. DLSS 5 is getting it's ass kicked on Youtube.

[Cookiemonsta234]

7 minutes ago, NCK30 said:

Don't You mean more fake AI looking. DLSS 5 is getting it's ass kicked on Youtube.

 

Yes, that is correct but I imagine they will improve and refine it over time. Honestly if DLSS 5 has a slider where you can adjust it to a lesser percentage it could potentially look better. The examples used looks overused like full maxed at 100%

Edited March 19 by Cookiemonsta234

[NCK30]

25 minutes ago, Cookiemonsta234 said:

 

Yes, that is correct but I imagine they will improve and refine it over time. Honestly if DLSS 5 has a slider where you can adjust it to a lesser percentage it could potentially look better. The examples used looks overused like full maxed at 100%

 

Some were downright different characters. Bland AI crap with fake skin.

and Todd Howard has already sold out and endorsed it.

Asmongold, MrMattyPlays and LegacyKilla were not happy about the quality.

After seeing it in slow-mo I would have to agree.
 

 

Okay. So apparantly Youtube links are also not working on LoversLab. This is getting annoying...
 

Edited March 19 by NCK30

[dagobaking]

17 hours ago, Cookiemonsta234 said:

This reddit post describes them all https://www.reddit.com/r/starfieldmods/comments/1rxlwyc/animation_tools_released/?share_id=rbw3o08NHM-1Xocjrn2wX&utm_content=1&utm_medium=android_app&utm_name=androidcss&utm_source=share&utm_term=1

 

Thank you. These do look like they could help. I'll have to dig further into them to see.

 

Not saying it isn't possible. But, from what I've learned so far, the starfield skeleton is apparently a big departure from skyrim/fallout skeletons. So, that will be a challenge to work through.

 

17 hours ago, Cookiemonsta234 said:

I also saw that Starfield was getting a DLSS 5 update which uses AI to change the appearance of characters and the environment to make them look more "life-like" https://www.nvidia.com/en-us/geforce/news/dlss5-breakthrough-in-visual-fidelity-for-games/

 

Yeah. I saw that. It's interesting. Raises a lot of questions:

A) How much of this feature will be open to modification? If it's changeable by the public like an ENB... It will end up being quite popular. Players could control the characteristics of an entire game in one place. Which is a large part of what modding as an entire activity tries to do.

 

B) They were pretty vague on requirements which is not good on many levels. Their examples required dual 5090 GPU. I'm sure a lot of optimization could happen. But, how bad would the quality get to make it consumer friendly with today's cards? It smells to me like they are assuming a cloud streaming delivery model for this. Not something you render on a home PC. And I'm pretty sure that the earth will stop rotating if/when they announce this.

 

11 hours ago, Cookiemonsta234 said:

Yes, that is correct but I imagine they will improve and refine it over time. Honestly if DLSS 5 has a slider where you can adjust it to a lesser percentage it could potentially look better. The examples used looks overused like full maxed at 100%

 

Yeah. They used a bad midjourney style model. The tech, with good choices, already works much better than that.

 

It would be pretty cool if they just made a tool that players could adjust directly if/when they turn it on. But, given that nVidia is one of the least cool and greediest companies on earth... I don't see them doing anything like that, sadly.