Logo Annotation Guidelines

The annotation Web interface is available at: https://hunger.openfoodfacts.org/logos.

The goal of the annotation is to provide ground-truth labels that will be used to predict the label of unseen logos.

It is extremely important to provide quality annotations, otherwise the predictions won't be qualitative.

How to?

1. Open web interface: https://hunger.openfoodfacts.org/logos

2. Select logos to be annotated (click each desired logo whit your mouse)

3. Fill value and type corresponding to the selected logos. Be sure to check that the value and type are correct before submitting the annotation :

• The value field should only be completed for "brand" and "label" types.
• The value should match one item in the associated taxonomy, otherwise it won't be used for prediction. The field value is lowercased before saving the annotation.

Example: https://hunger.openfoodfacts.org/logos?logo_id=161643 Here, we should add "label rouge" as value and "label" as type. Server-side, the value is transformed into a tag ("label-rouge") and matched against the taxonomy to associate the real taxonomy ID to the value ("en:label-rouge").

Lang prefixes ("en:", "fr:") should not be added, otherwise the taxonomy match will fail.

Example of valid values:

• gluten-free
• volaille française
• auchan
• reflets de france

Example of invalid values:

• en:gluten-free
• fr:volaille française

If more than one logo is visible on the crop, do not annotate it. A flag system should be available in the future to report them.

If the logo is truncated, annotate it anyway if it can still be recognized.

You can click on the blue link on the top-right corner of each logo card. It will open a new tab with this specific logo as reference. It's really useful to find similar logos to annotate.

Query parameters:

• logo_id: the ID of the logo. If not provided, will be random.
• count: the number of results to display (default: 25). Useful to annotate many logos at once.