Firmware hack for Wolverine 8mm film digitiser

There are a number of budget 8mm film digitisers available, the two most well known are probably the Kodak Reels and the Wolverine, and I purchased a Wolverine back in 2021. The Wolverine is actually available in two versions: the base model for $300 USD and the Wolverine Pro for $400. The main differences between them are the Pro can load large film spools up to 9" diameter and captures the video at 1080p. The standard Wolverine can only support up to 5" reels and captures video at 720p.

But here's the kicker, both devices use exactly the same camera and capture technology, the difference in resolution is set by the device firmware. The image sensor actually has a whopping capture resolution of 2304 pixels wide by 1536 pixels high.

Thankfully, a bunch of really smart people (not me, I promise you) have created a bunch of tools that allow end users to edit the original firmware and allow the Wolverine to capture video with much higher resolution and better quality compression rates.

Here's a summary of how this is achieved, with more details provided later in this article:

• Decompress the Wolverine firmware binary with bfc4ntk.exe application (this has already been done in the attached archive).
• Modify resolution/bitrate using NtkMPE.jar tool.
• Compress updated firmware with bfc4ntk.exe application.
• Write new checksum to the compressed firmware with ntkcalc-v051.exe.
• Flash the new firmware to the Wolverine.

The two applications: bfc4ntk.exe and ntkcalc-v051.exe are self-contained command-line executable files for PC, but the NtkMPE.jar is a Java file, which requires Java be installed on your computer.

Before getting into the nitty gritty, I need to mention my good friend Steve from Mac84 who did the majority of research into this process while hacking is own Kodak Reels. He sourced all the tools and firmware files and sent them to me to try on my Wolverine. Read about his journey here.

WARNING! Editing firmware can have detrimental results if things go wrong, and I accept no responsibility if you attempt this and "brick" your Wolverine, turning it into an expensive doorstop. And it goes without saying, making changes like this will almost definitely void your product warranty.​

Included in the attached archive is the original firmware. I can't say for certain if this is the same firmware on all Wolverine devices, I can only tell you it does work on my model: the Wolverine F2D MovieMaker.

I have placed all of the necessary files into the same directory. This makes things easier when typing out the command line instructions. This guide assumes a basic knowledge of the Windows command prompt, such as using cd to change directories and dir for viewing a directory list.

Resolution​

The aspect ratio of the captured video from the Wolverine is 4:3, so you can calculate the height based on the width with (W÷4) x 3 = H. This can also be expressed as W x 0.75 = H.

You can calculate the width based on the height with (H÷3) x 4 = W. This can also be expressed as H x 1.333… = W. So let's give it a try. 720p video has a height of 720 pixels, so the width will be 720 x 1.333… which rounds to a width of 960 pixels. And what if we start with a width of 1280 pixels? The height will be 1280 x 0.75 which makes the height 960 pixels.

Here is a list of common 4 x 3 resolutions, all of which I have tried and work with the Wolverine:

Bitrate​

This firmware hack also allows you to change the bitrate, effectively controlling how much compression is applied to the video when writing to the SD card. The default high level of compression is one of the biggest complaints I hear about the Wolverine, so this is a fantastic fix.

FPS​

The other setting you can change is the FPS or Frames Per Second. By default the Wolverine captures at 30 FPS, as this is a fairly common video frame rate. However, 8mm film is natively 18fps (though this can vary based on the camera) and recording at 30 FPS will NOT smooth out your video. For this reason, I do most of my captures at 20fps. Be aware that the Wolverine will not accept FPS settings lower than 20.

Don't expect too much​

One last thing I should mention is that the little CPU inside the Wolverine definitely has limits, and you need to find the right balance of resolution and bitrate. If you set these values too high, the resulting file will be too large for the frame buffer to handle, and the Wolverine will record nothing. I have provided a matrix of resolution/bitrate combinations I have tried, indicating which ones work and which ones don't.


If your results contradict any of these, please let me know!

What setting should I use?​

Well I'm glad you asked. While this firmware hack does allow you to capture at up to 1920 x 1440, is there any benefit in doing so? Let's not forget we're talking about 8mm film here. Maybe your films were shot by Steven Spielberg, but most of my home movies are pretty rough around the edges. Some aren't even in focus!

So do you actually capture more detail with a higher resolution? Based on my tests, the answer is no. In fact a higher resolution will force you into a lower bitrate, and as a result you could end up losing fine detail due to over compression.

Have a look at the following image. On the left is part of a frame captured at 1920 x 1440 and a bitrate of 6,400, and on the right is the same part of the same frame captured at 1440 x 1080 and a bitrate of 17,600. I have scaled the 1080p frame up to match the size of the 1440p frame. The frame on the left has been decimated by the high compression and has resulted in a significant loss in detail. If you look at the right image, you can see the actual film grain, but the image on the left has been all smoothed out. Take a look at the detail in the waves of the white planter, and the variegated leaves of the plant, there's just no way the higher resolution is better.

I did these same tests with a whole range of resolutions, and I have concluded that capturing at 1080p with the highest available bitrate gives me the best result. Things may be different with your films, but for me, 1080p is the go.

Firmware hack instructions​

1. Decompress the attached Wolverine Tools.zip archive to your Windows computer.
2. If you haven't already, install Java on your computer.
3. Launch the NtkMPE.jar file from the Windows Tools directory.
4. Select File > Open Ntk firmware and navigate to the new_firmware.rbn file in the Wolverine Tools directory and open it.
5. You will see 6 columns and 5 rows of data. You can ignore the first four rows, the last row is the only one that has an effect. The columns are Address, Width, Height, FPS, Bitrate/2 and Aspect. Ignore the Address column, and as far as I can tell, Aspect has no effect, so leave this set to zero. Click the field you want to edit and replace the existing figure with your new one.
   
   
   
6. Once you have made your changes to the fields, select Apply modifications from the menu bar to apply the updates to the new_firmware.rbn file. At the bottom of the window a message will appear, indicating how many parameters were changed.
7. Launch the Windows Command Prompt (cmd.exe)
8. Navigate to the Windows Tools directory (e.g. cd "C:/Users/username/Documents/Windows Tools")
9. Type the following to compress the edited firmware file: bfc4ntk.exe -p new_firmware.rbn FWDV180N.bin
10. Type the following to write a new checksum to the compressed firmware file: ntkcalc-v051.exe -cw FWDV180N.bin
11. Copy the new FWDV180N.bin file to the root directory of your Wolverine SD card. It must be in the root directory for the Wolverine to detect it.
12. Make sure the Wolverine is powered off. Insert the SD card and power on the Wolverine. The power light will start flashing slowly, then it will flash fast, then the Wolverine will power on with the standard welcome screen. The whole process should take around 20 seconds.
13. Power off the Wolverine, remove the SD card then delete the FWDV180N.bin file, otherwise it will keep loading the same firmware every time you power the Wolverine on.
14. Insert the SD card back into your Wolverine, power it on and start capturing.

If you encounter an issue, such as no video file being created after capture, this is probably because you have selected a resolution or bitrate that the Wolverine doesn't like. If this happens, go back to step 3 and try some different settings. Try using one of the safe settings from my supplied matrix (above).