> ## Documentation Index
> Fetch the complete documentation index at: https://unstructured-53-docs-245-multimodal.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.
# Image descriptions
After partitioning, you can have Unstructured generate text-based summaries of detected images.
This summarization is done by using models offered through various model providers.
Here is an example of the output of a detected image using GPT-4o. Note specifically the `text` field that is added.
Line breaks have been inserted here for readability. The output will not contain these line breaks.
```json theme={null}
{
"type": "Image",
"element_id": "3303aa13098f5a26b9845bd18ee8c881",
"text": "{\n \"type\": \"graph\",\n \"description\": \"The graph shows
the relationship between Potential (V) and Current Density (A/cm2).
The x-axis is labeled 'Current Density (A/cm2)' and ranges from
0.0000001 to 0.1. The y-axis is labeled 'Potential (V)' and ranges
from -2.5 to 1.5. There are six different data series represented
by different colors: blue (10g), red (4g), green (6g), purple (2g),
orange (Control), and light blue (8g). The data points for each series
show how the potential changes with varying current density.\"\n}",
"metadata": {
"filetype": "application/pdf",
"languages": [
"eng"
],
"page_number": 1,
"image_base64": "/9j......Q==",
"image_mime_type": "image/jpeg",
"filename": "7f239e1d4ef3556cc867a4bd321bbc41.pdf",
"data_source": {}
}
}
```
The `image_base64` field is generated only for documents or PDF pages that are [partitioned](/ui/partitioning) by using the High Res strategy. This field is not generated for
documents or PDF pages that are partitioned by using the Fast or VLM strategy.
For workflows that use [chunking](/ui/chunking), note the following changes:
* Each `Image` element is replaced by a `CompositeElement` element.
* This `CompositeElement` element will contain the image's summary description as part of the element's `text` field.
* This `CompositeElement` element will not contain an `image_base64` field.
Here are three examples of the descriptions for detected images. These descriptions are generated with GPT-4o by OpenAI:
Any embeddings that are produced after these summaries are generated will be based on the `text` field's contents.
## Generate image descriptions
To generate image descriptions, in an **Enrichment** node in a workflow, select **Image**, and then choose one of the available provider (and model) combinations that are shown.
You can change a workflow's image description settings only through [Custom](/ui/workflows#create-a-custom-workflow) workflow settings.
For workflows that use [chunking](/ui/chunking), the **Chunker** node should be placed after all **Enrichment** nodes. Placing the
**Chunker** node before an image descriptions **Enrichment** node could cause incomplete or no image descriptions to be generated.
The following models are no longer available as of the following dates:
* Amazon Bedrock Claude Sonnet 3.5: October 22, 2025
* Anthropic Claude Sonnet 3.5: October 22, 2025
Unstructured recommends the following actions:
* For new workflows, do not use any of these models.
* For any workflow that uses any of these models, update that workflow as soon as possible to use a different model.
Workflows that attempt to use any of these models on or after its associated date will return errors.
Unstructured can potentially generate image summary descriptions only for workflows that are configured as follows:
* With a **Partitioner** node set to use the **Auto** or **High Res** partitioning strategy, and an image summary description node is added.
* With a **Partitioner** node set to use the **VLM** partitioning strategy. No image summary description node is needed (or allowed).
Even with these configurations, Unstructured actually generates image summary descriptions only for files that contain images and are also eligible
for processing with the following partitioning strategies:
* **High Res**, when the workflow's **Partitioner** node is set to use **Auto** or **High Res**.
* **VLM** or **High Res**, when the workflow's **Partitioner** node is set to use **VLM**.
Unstructured never generates image summary descriptions for workflows that are configured as follows:
* With a **Partitioner** node set to use the **Fast** partitioning strategy.
* With a **Partitioner** node set to use the **Auto**, **High Res**, or **VLM** partitioning strategy, for all files that Unstructured encounters that do not contain images.
Any embeddings that are produced after these summaries are generated will be based on the `text` field's contents.
## Generate image descriptions
To generate image descriptions, in an **Enrichment** node in a workflow, select **Image**, and then choose one of the available provider (and model) combinations that are shown.