ImageAlt TextConverter
Generate WCAG-compliant alt text for images using a vision-language model fine-tuned for accessibility. Produces concise, descriptive text that conveys the meaning and function of images for screen reader users, with support for context-aware and decorative image detection.
How It Works
Upload an image or provide a URL to the Mixpeek API.
The image is classified as informative, decorative, functional, or complex.
A vision-language model generates alt text appropriate to the image type and context.
The alt text is checked against WCAG 2.1 guidelines for length, specificity, and relevance.
Alt text is returned with the image classification and a compliance confidence score.
Code Examples
import os, requests
API = "https://api.mixpeek.com"
H = {"Authorization": f"Bearer {os.environ['MIXPEEK_API_KEY']}",
"X-Namespace": os.environ["NAMESPACE_ID"]}
# 1. a bucket, with a schema that declares the field you will send
bucket = requests.post(f"{API}/v1/buckets", headers=H, json={
"bucket_name": "image-inputs",
"bucket_schema": {"properties": {"image": {"type": "image"}}},
}).json()
# 2. land the file as an object. the URL goes in data, on the blob
requests.post(f"{API}/v1/buckets/{bucket['bucket_id']}/objects", headers=H, json={
"key_prefix": "run-1",
"blobs": [{"property": "image", "type": "image",
"data": "https://example.com/photo.jpg"}],
})
# 3. a collection over that bucket, running the extractor
collection = requests.post(f"{API}/v1/collections", headers=H, json={
"collection_name": "image-to-alt-text",
"source": {"type": "bucket", "bucket_ids": [bucket["bucket_id"]]},
"feature_extractor": {"feature_extractor_name": "image_extractor", "version": "v1"},
}).json()
# 4. run extraction over the bucket
requests.post(f"{API}/v1/buckets/{bucket['bucket_id']}/batches", headers=H, json={
"collection_ids": [collection["collection_id"]],
"auto_submit": True,
})
# 5. read the output
docs = requests.get(
f"{API}/v1/collections/{collection['collection_id']}/documents", headers=H
).json()
print(docs)Use Cases
Supported Input Formats
Quick Info
Run it over a library
Mixpeek runs this conversion as a pipeline over a whole library in your object storage, with the output landing as queryable documents. It is not a single-file converter.
Frequently Asked Questions
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Ready to convert image to alt text?
Start using the Mixpeek Image to Alt Text in minutes. Sign up for a free API key and follow the documentation to get started.