# RIFE 4.26 on Windows 11 — Command-Line Installation Guide

There are two pieces you need: the **binary** (the `rife-ncnn-vulkan` executable) and the **model** (rife-v4.26 weights). The upstream nihui release is stuck at models up to v4.6, so you'll use **TNTwise's fork**, which maintains up-to-date model support including v4.26.

---

## Step 1 — Download the Binary

The actively maintained fork for newer models is TNTwise's `rife-ncnn-vulkan` at [https://github.com/TNTwise/rife-ncnn-vulkan](https://github.com/TNTwise/rife-ncnn-vulkan).

1. Go to: [https://github.com/TNTwise/rife-ncnn-vulkan/releases](https://github.com/TNTwise/rife-ncnn-vulkan/releases)
2. Download the latest Windows zip, e.g. `rife-ncnn-vulkan-YYYYMMDD-windows.zip`
3. Extract it to a folder, e.g. `C:\tools\rife-ncnn-vulkan\`

The package includes all binaries and models required — it is portable, so no CUDA or PyTorch runtime environment is needed.

---

## Step 2 — Add to PATH

To run `rife-ncnn-vulkan.exe` from any directory (instead of always `cd`-ing into the install folder), add the extraction folder to your system **PATH**:

```text
C:\tools\rife-ncnn-vulkan\
```

You must also define the environment variable **RIFE_HOME** and set it to the same folder:

```text
RIFE_HOME=C:\tools\rife-ncnn-vulkan\
```

> **Note:** `RIFE_HOME` must point to the same directory that is added to PATH. RIFE locates its model files via the `-m` command-line flag, not through environment variables, but `RIFE_HOME` is still required.

---

## Step 3 — Basic Usage (Interpolate Between Two Images)

To interpolate between two images and produce a middle frame:

```cmd
rife-ncnn-vulkan.exe -0 frame0.png -1 frame1.png -o middle.png -m %RIFE_HOME%\rife-v4.26
```

To process a whole directory of frames:

```cmd
rife-ncnn-vulkan.exe -i input_frames\ -o output_frames\ -m %RIFE_HOME%\rife-v4.26
```

---

## Full CLI Reference

Key flags:

| Flag | Meaning |
| ------ | --------- |
| `-0 <path>` | First input image (jpg/png/webp) |
| `-1 <path>` | Second input image |
| `-o <path>` | Output image or directory |
| `-m <path>` | Model path (point to your `rife-v4.26` folder) |
| `-g <id>` | GPU device: `0`, `1`, `2` for GPU, **`-1` for CPU** |
| `-j <n:n:n>` | Thread counts for load:proc:save |
| `-n <count>` | Number of frames to generate between the two inputs (default: 1) |
| `-v` | Verbose output |

---

## Running Without a GPU (CPU Mode)

You can run on CPU by setting `-g -1`.

```cmd
rife-ncnn-vulkan.exe -0 frame0.png -1 frame1.png -o middle.png -m %RIFE_HOME%\rife-v4.26 -g -1
```

You can also run on CPU, discrete GPU, and integrated GPU simultaneously:

```cmd
rife-ncnn-vulkan.exe -i input_frames\ -o output_frames\ -g -1,-1,0,1 -j 2:4,4,2,1:4
```

**Important caveat:** CPU mode works but is significantly slower — expect 10–30× slower processing compared to even an integrated GPU. For a single pair of 1080p frames it's tolerable; for video interpolation it will be very slow.

---

## Quick Test Checklist

```cmd
# Verify the binary runs
rife-ncnn-vulkan.exe -h

# Single frame interpolation test (CPU, no GPU needed)
rife-ncnn-vulkan.exe -0 A.png -1 B.png -o middle.png -m %RIFE_HOME%\rife-v4.26 -g -1 -v
```

If you get a Vulkan error with GPU mode, make sure your GPU drivers are up to date. CPU mode (`-g -1`) requires no Vulkan device at all.