# Image recognition: update the photos' fingerprint

> For the administrator: update the catalog's image recognition so Dri finds the product from the photo the customer sends.

Source: https://vendria.com/en/ajuda/reconhecimento-de-imagens

## Where to find it

In your account menu, under **Catalog and exports**, **Import** tab, in the
**Image recognition** card. The button is **Update image
recognition**.

Like everything in the **Import** tab, the action applies to the store chosen in the
**Store** selector at the top of the tab.

## What image recognition does

When a customer sends a **photo of a product** (no code, just the item), Dri
tries to find in the catalog the product shown in the photo. For that, each catalog
photo needs a **fingerprint**: a summary of the image that lets it be
compared quickly with the photo that arrived.

The fingerprint is generated automatically whenever a photo enters Vendria: through
the spreadsheet import, the image import or the product edit. The
**Update image recognition** button exists for the cases where this
fell behind: products that got a photo through a path that did not generate the
fingerprint, or a generation that failed.

Without a fingerprint, the product stays in the catalog normally, photo and
all; it just isn't found by the photo search.

## When to use it

- after a large photo import, if customers send photos of products
  that Dri doesn't recognize;
- when the window shows products under **Without recognition (precomputed hash)**;
- when Vendria support asks you to recompute everything.

You don't need to run it after every import: normally the number of pending items
is already zero.

## Step by step to update the recognition

1. Check the store in the **Store** selector.
2. Click **Update image recognition**. The window of the same name
   opens.
3. Read the three numbers: **Total** (the store's active products), **With image**
   (how many have a photo) and **Without recognition (precomputed hash)** (how many have
   a photo but lack a complete fingerprint).
4. Click **Recalculate missing**. The bar shows the progress, product by
   product.
5. At the end, **Updated**, **Images** and **Failures** appear. Click
   **Close**.

The window doesn't close while the recalculation is running. Running it again is safe:
the recalculation only touches items that are still pending.

## Recompute everything

The **Recompute all (after changing the canonicalization)** switch makes the recalculation
go through **all** products with a photo, not just the pending ones. The button
is then called **Recompute all**. Use it only when Vendria support
tells you to: on a large catalog it takes much longer, and for normal use
**Recalculate missing** is enough.

## What the button doesn't solve

- **A product without a photo** doesn't enter the photo search. Import the photo first. See [Import the product photos](/en/ajuda/importar-imagens-dos-produtos).
- **Failures** in the result are photos that could not be read (corrupted or
  unavailable file). Replace the product's photo and run it again.
- If the store turned off visual recognition, or prefers the written code, the photo
  may be read as a document even with all fingerprints up to date. See [Foto de produto sem código: como a Dri reconhece, e quando ela prefere ler](/ajuda/foto-de-produto-sem-codigo).

## When it goes wrong

**"Error checking hash coverage."** The window couldn't count the
pending items. Close and open it again; the **Recalculate missing** button is only enabled
after the count.

**"I ran it and the customer still sends photos Dri can't find."** Check that the product
has a photo and is active, and that the catalog photo shows the product in a way
similar to how the customer photographs it: a photo of a closed package and one
of a loose item may not look alike enough.