In Part 2 of our , we show how foundation models (e.g., GPT-4o, Claude Sonnet 3.5 and YOLO-World) can be used to generate visual inputs (e.g., bounding boxes) for SAM 2. Learn how this approach is likely to disrupt the field of Computer Vision as we know it.
�
In case you missed Part 1:
- — SAM 2 + GPT-4o Cascading Foundation Models via Visual Prompting.
�
🔥 Learn more about the cutting edge of and foundation models in our CVPR 2024 series:
- (RAG, Multimodal, Embeddings, and more).
- — Embodied AI, GenAI, Foundation Models, and Video Understanding.
�
Table of contents
- Cascading Foundation Models
- Foundation Models as Visual Prompting tools
- GPT-4o (or Claude Sonnet 3.5) + SAM 2
- YOLO-World + SAM 2
- Conclusions
�
1. Cascading Foundation Models
1.1 Recap from Part 1
In , we introduced Segment Anything Model 2 (SAM 2) [1], an object segmentation model for images and video:
- SAM 2 treats images as single-frame videos, using memory to process both images and videos uniformly.
- It allows for promptable segmentation in videos, making predictions and refining them across frames based on user input.
- SAM 2 is trained on the large SA-V dataset, leading to state-of-the-art performance in video segmentation.
�
        Figure 1. SAM 2 applied to a custom video in
�
Figure 1 demonstrates a practical application of SAM 2. Our provides step-by-step instructions for setting up and running SAM 2 on your own machine.
�
1.2 What do we mean by cascading foundation models?
Cascading foundation models simply means assembling a pipeline where you use the outputs of one model as inputs for a subsequent model.
�
You may ask, “But what’s novel about this approach?� 🤔 The answer lies in the Zero-Shot [2] nature of foundation models. Models such as GPT-4o or SAM 2 are called zero-shot, which means they can perform inference without a previous training step. As a result, these models can be connected in a systems perspective, as illustrated in Figure 2.

�
In fact, some research approaches such as CaFO [3] combine multiple pre-trained foundation models (CLIP, DINO, DALL-E, GPT-3) to enhance few-shot visual recognition by leveraging diverse pre-training knowledge and generating synthetic data.
�
2. Foundation Models as Visual Prompting tools
2.1 Computer Vision Pipeline 2.0: a new paradigm
We have explored before . It refers to using visual information (like images, bounding boxes, or points) as inputs or “prompts� for foundation models that can process both visual and textual information.
�
One of the key strengths at ÍøÆØÃÅ is visual search. We process tens of thousands of daily queries using visual prompting. For instance, Figure 3 shows how you can select a bounding box of an object to search for fine-grained details in your data.
�
Figure 3. Using visual prompting to search for objects (e.g., school buses) even if no class for this object exist
�
As we have previously argued, at ÍøÆØÃÅ, we believe that the traditional pipeline in the field of vision is at the beginning of a transition where many stages in the pipeline (e.g., labeling, training) will be replaced by modules containing that will form a so-called .
�
2.2 Challenges of Visual Prompting as a glue for Foundation Models
Now, when you start to connect foundation models together, you immediately notice that building a robust system based on this paradigm is not the same as building a prototype over the weekend.
�
Here are some of the main challenges you can expect to encounter as soon as you get started:
�
1. Performance and Scalability 🚀📈
- Ensuring the system can handle high volumes of data and requests in real-time.
- Maintaining accuracy and speed as the scale of operations increases.
�
2. Integration and Compatibility 🔗🛠�
- Seamlessly incorporating the multi-model system into existing infrastructure.
- Ensuring interoperability with various data formats, APIs, and legacy systems.
�
3. Reliability and Error Handling 🔄🛡�
- Developing robust error detection and correction mechanisms.
- Implementing redundancies to maintain operational continuity.
�
3. GPT-4o (or Claude Sonnet 3.5) + SAM 2
3.1 A visual prompting pipeline

�
Figure 4 shows a simple pipeline consisting of two steps. The assumption is that GPT-4o or Claude Sonnet 3.5 are powerful enough for a prompt such as:
“For the given image, please provide three (x,y) coordinates of the gymnast�
“For the given image, please provide the bounding box coordinates of the gymnast�
�
Figure 5 and 6 show the results for GPT-4o and Claude Sonnet 3.5 respectively.


While GPT-4o, most of the time, provides incorrect coordinates, Claude Sonnet 3.5 simply refuses to provide either (x,y) coordinates or bounding boxes.
�
Figure 7 shows how this behaviour was consistent across 200 API requests for GPT-4o.

So, can’t we really use any decent foundation model (in 2024) as input for a second foundation model? 😱
�
4. YOLO World + SAM 2
4.1 Zero-shot for Computer Vision: YOLO-World
Despite our hopes being crushed by realizing that neither GPT-4o nor Claude Sonnet 3.5 is good enough to provide visual answers from an image, we found a specialized model that made the cut: YOLO-World [4].
�
Figure 7 shows how, given a text input (i.e., classes), this model accurately predicts the bounding boxes for each of the given inputs! �
�
YOLO-World’s vocabulary even includes the word: gymnast! (see 0.93 mAP on the right hand side of Figure 8).

- 🔥 Spoiler alert: We’ll be discussing more about YOLO-World (Zero-Shot) vs YOLO v8 (Fine-tuning) in an upcoming post!
�
For starters, YOLO-World is a zero-shot model for object detection that can detect and localize objects in images without requiring prior training on specific object classes.
�
We used YOLO-World to provide bounding boxes to SAM 2 as shown in Figure 9.

�
The only input we were required to provide to the whole system was the class definition for the YOLO-World vocabulary, in this case, “gymnast.� This word is enough for YOLO-World to provide the bounding box coordinates to SAM 2.
�
Check this for details on the implementation. The final result is shown in Figure 8.
�
5. Conclusions
In this series about SAM 2, we described and set up the Segment Anything Model 2 (SAM 2). Then, we cascaded two foundation models (i.e., we used the outputs of model A as the inputs for model B) using visual prompting.
�
We discovered that the two leading in the market, GPT-4o and Claude Sonnet 3.5, are quite inaccurate at providing coordinates or bounding boxes of objects for a given image. Instead, we found that specialized models (e.g., YOLO-World) are better suited for this job.
�
is one thing, but in reality, there are challenges that even the best ML teams struggle with (e.g., integration, reliability, and adaptability when chaining together foundation models).
�
How can you address all these challenges for your system while keeping maintenance costs low? 💸 ↘� . Well, has taken the time to build visual prompting for interconnected foundation models so that you don’t have to.
�
As we have argued before, a new paradigm in computer vision is here: some traditional stages in a vision pipeline are likely to be replaced by (zero-shot) foundation models that will continually improve over time.
�
How long do we have to wait to get precise bounding box coordinates from the upcoming GPT member of the family? Probably not long.
🔥 Learn about Multimodal Large Language Models (MLLM):
- 🆕 (MLLMs) transforming Computer Vision
�
References
[ Segment Anything Model 2
�
[] An embarrassingly simple approach to zero-shot learning
�
[] Prompt, Generate, then Cache: Cascade of Foundation Models makes Strong Few-shot Learners
�
[] YOLO-World: Real-Time Open-Vocabulary Object Detection
�
Authors: Jose Gabriel Islas Montero, Dmitry Kazhdan
�
If you’d like to know more about ÍøÆØÃÅ, try .

�
�












