---
title: "VertexAIImageQA"
id: vertexaiimageqa
slug: "/vertexaiimageqa"
description: "This component enables text generation (image captioning) using Google Vertex AI generative models."
---

# VertexAIImageQA

This component enables text generation (image captioning) using Google Vertex AI generative models.

<div className="key-value-table">

|  |  |
| --- | --- |
| **Mandatory run variables** | `image`: A [`ByteStream`](../../concepts/data-classes.mdx#bytestream)  containing an image data  <br /> <br />`question`: A string of a question about the image |
| **Output variables** | `replies`: A list of strings containing answers generated by the model |
| **API reference** | [Google Vertex](/reference/integrations-google-vertex) |
| **GitHub link** | https://github.com/deepset-ai/haystack-core-integrations/tree/main/integrations/google_vertex |

</div>

`VertexAIImageQA` supports the `imagetext` model.

### Parameters Overview

`VertexAIImageQA` uses Google Cloud Application Default Credentials (ADCs) for authentication. For more information on how to set up ADCs, see the [official documentation](https://cloud.google.com/docs/authentication/provide-credentials-adc).

Keep in mind that it’s essential to use an account that has access to a project authorized to use Google Vertex AI endpoints.

You can find your project ID in the [GCP resource manager](https://console.cloud.google.com/cloud-resource-manager) or locally by running `gcloud projects list` in your terminal. For more info on the gcloud CLI, see its [official documentation](https://cloud.google.com/cli).

## Usage

You need to install `google-vertex-haystack` package to use the  `VertexAIImageQA`:

```python
pip install google-vertex-haystack
```

### On its own

Basic usage:

```python
from haystack.dataclasses.byte_stream import ByteStream
from haystack_integrations.components.generators.google_vertex import VertexAIImageQA

qa = VertexAIImageQA()

image = ByteStream.from_file_path("dog.jpg")

res = qa.run(image=image, question="What color is this dog")

print(res["replies"][0])

>>> white
```

You can also set the number of answers generated:

```python
from haystack.dataclasses.byte_stream import ByteStream
from haystack_integrations.components.generators.google_vertex import VertexAIImageQA

qa = VertexAIImageQA(
    number_of_results=3,
)
image = ByteStream.from_file_path("dog.jpg")

res = qa.run(image=image, question="Tell me something about this dog")

for answer in res["replies"]:
    print(answer)

>>> pomeranian
>>> white
>>> pomeranian puppy
```