With 128GB of unified memory and powerful GPU acceleration, DGX Spark provides an ideal environment for training VRAM-intensive multimodal models that can understand and reason about visual content.
Both approaches leverage advanced training techniques, including LoRA fine-tuning, preference optimization, and structured reasoning to achieve superior performance on specialized tasks.
You will have fine-tuned VLM models capable of understanding and analyzing both images and videos for specialized use cases, accessible through interactive Web UIs.
The setup includes:
- **Image VLM**: Qwen2.5-VL fine-tuned for wildfire detection with reasoning capability
- **Video VLM**: InternVL3 fine-tuned for dangerous driving analysis and structured metadata generation
- Interactive Streamlit interfaces for both training and inference
- Side-by-side model comparison (base vs fine-tuned) in the Web UIs
- Docker containerization for reproducible environments
## Prerequisites
- DGX Spark device is set up and accessible
- No other processes running on the DGX Spark GPU
- Enough disk space for model downloads and datasets
- NVIDIA Docker installed and configured
- Weights & Biases account for training monitoring (optional but recommended)
## Time & risk
**Duration**:
- 15-20 minutes for initial setup and model downloads
- 30-60 minutes for image VLM training (depending on dataset size)
- 1-2 hours for video VLM training (depending on video dataset size)
To easily manage containers without sudo, you must be in the `docker` group. If you choose to skip this step, you will need to run Docker commands with sudo.
Open a new terminal and test Docker access. In the terminal, run:
```bash
docker ps
```
If you see a permission denied error (something like `permission denied while trying to connect to the Docker daemon socket`), add your user to the docker group:
```bash
sudo usermod -aG docker $USER
```
> **Warning**: After running usermod, you must log out and log back in to start a new
> session with updated group permissions.
## Step 2. Clone the repository
In a terminal, clone the repository and navigate to the VLM fine-tuning directory.
**Note**: The same Docker container and launch commands work for both image and video VLM recipes. The container includes all necessary dependencies, including FFmpeg, Decord, and optimized libraries for both workflows.
If you already have a fine-tuned checkpoint, place it in the `saved_model/` folder. Note that your checkpoint number can be different. For a comparative analysis against the base model, skip directly to the `Finetuned Model Inference` section.
Access the streamlit demo at http://localhost:8501/.
When you access the streamlit demo for the first time, the backend triggers vLLM servers to spin up for the base model. You will see a spinner on the demo site as vLLM is being brought up for optimized inference. This step can take upto 15 mins.
#### 5.4. GRPO Finetuning
We will perform GRPO finetuning to add reasoning capabilities to our base model and improve the model's understanding of the underlying domain. Considering that you have already spun up the streamlit demo, scroll to the `GRPO Training section`.
After configuring all the parameters, hit `Start Finetuning` to begin the training process. You will need to wait about 15 minutes for the model to load and start recording metadata on the UI. As the training progresses, information such as the loss, step, and GRPO rewards will be recorded on a live table.
The default loaded configuration should give you reasonable accuracy, taking 100 steps of training over a period of upto 2 hours. We achieved our best accuracy with around 1000 steps of training, taking close to 16 hours.
After training is complete, the script automatically merges LoRA weights into the base model. After the training process has reached the desired number of training steps, it can take 5 mins to merge the LoRA weights.
Now we are ready to perform a comparative analysis between the base model and the finetuned model.
Regardless of whether you just spun up the demo or just stopped training, please wait about 15 minutes for the vLLM servers to be brought up.
Scroll down to the `Image Inference` section, and enter your prompt in the provided chat box. Upon clicking `Generate`, your prompt would be first sent to the base model and then to the finetuned model. You can use the following prompt to quickly test inference
`Identify if this region has been affected by a wildfire`
If you trained your model sufficiently, you should see that the finetuned model is able to perform reasoning and provide a concise, accurate answer to the prompt. The reasoning steps are provided in the markdown format, while the final answer is bolded and provided at the end of the model's response.
> **Note**: These instructions assume you are already inside the Docker container. For container setup, refer to the main project README at `vlm-finetuning/assets/README.md`.
When you access the streamlit demo for the first time, the backend triggers Huggingface to spin up the base model. You will see a spinner on the demo site as the model is being loaded, which can take upto 10 minutes.
First, let's select a video from our dashcam gallery. Upon clicking the green file open icon near a video, you should see the video render and play automatically for our reference.
If you are proceeding to train a finetuned model, ensure that the streamlit demo UI is brought down before proceeding to train. You can bring it up by interrupting the terminal with `Ctrl+C` keystroke.
> **Note**: To clear out any extra occupied memory from your system, execute the following command outside the container after interrupting the ComfyUI server.
Access Jupyter at `http://localhost:8888`. Ensure that you set the path to your dataset correctly in the appropriate cell.
```python
dataset_path = "/path/to/your/dataset"
```
After training, ensure that you shutdown the jupyter kernel in the notebook and kill the jupyter server in the terminal with a `Ctrl+C` keystroke.
> **Note**: To clear out any extra occupied memory from your system, execute the following command outside the container after interrupting the ComfyUI server.
```bash
sudo sh -c 'sync; echo 3 > /proc/sys/vm/drop_caches'
Now we are ready to perform a comparative analysis between the base model and the finetuned model.
If you haven't spun up the streamlit demo already, execute the following command. If you have just stopped training and are still within the live UI, skip to the next step.
```bash
streamlit run Video_VLM.py
```
Access the streamlit demo at http://localhost:8501/.
If you trained your model sufficiently, you should see that the finetuned model is able to identify the salient events from the video and generate a structured output.