# Conference and corporate event photo delivery by face

> Attendees opt in when they register, and their photos arrive after each day of the event without anyone having to search.

Source: https://sightradar.com/use-cases/conference-event-photos

Conferences already know who is coming. That changes the design: instead of a public selfie box, attendees opt in during registration, and you send their photos to them after each day. Marketing teams get a second use from the same index, pulling every photo of a speaker or a sponsor booth for the recap post.

**Who builds this:** Event-tech platforms, registration and badge vendors, and in-house event and marketing teams.

## How it goes together

1. **One collection per event** (`POST /v1/collections`): Keep a multi-day event in one collection so that a search on day three also covers day one.
2. **Enrol opted-in attendees at registration** (`POST /v1/collections/{id}/selfies`): Add an optional "send me my photos" step with a headshot upload, keyed by the attendee's registration ID as `userId`. Store the returned `point_id` on the attendee record. Attendees who skip the step are never enrolled.
3. **Batch-index each day's photos** (`POST /v1/webhooks  +  POST /v1/batches`): Register a webhook endpoint once, before the first batch, and pass its `webhook_endpoint_id` on every batch. Photographers upload at the end of each day; send one batch per upload. Verify the HMAC signature on every delivery, and dedupe on the idempotency key.
4. **Match every enrolled attendee after each day** (`POST /v1/collections/{id}/search-by-id`): When the day's batch completes, run one search by id per enrolled attendee and email or push the new photo ids. No selfie is uploaded again.
5. **Find the speakers and the sponsor booth** (`POST /v1/collections/{id}/search`): With the speaker's agreement, search by their headshot to pull every photo of them for the recap post or the sponsor report.

Operations: Register selfie · Batch index · Webhooks · Search by id.

## What is different about conferences

- Opt-in happens before anyone is photographed. Registration is the natural consent moment, and it already gives you a name and an email address to deliver to.
- Photos are pushed, not searched for. One search by id per attendee per day costs less than a search by image every time someone opens the app, and attendees do not have to remember to look.
- Employees are a special case. At internal company events the employer holds the power, and European regulators' guidance treats employee consent as rarely freely given. Keep enrolment optional and offer a way to get photos that does not involve a face.
- Photographers keep shooting as normal. Only enrolled attendees are ever matched, but every face in an indexed photo is stored as a faceprint until you delete the collection.

## Cost example: A three-day conference with 2,000 attendees

Assumptions (illustrative volumes, not customer data):

- 25,000 photos over three days, batch-indexed
- 900 attendees opt in and register a headshot (real-time rate)
- Each enrolled attendee is matched once per day: 2,700 searches by id
- 20 speaker and sponsor searches by image (real-time rate)
- About 3 faces per photo (75,000 stored faces) plus 900 stored headshots, kept for 1 month

| Line | Quantity | Rate | Cost |
| --- | --- | --- | --- |
| Index event photos | 25,000 | $0.00062 / photo (batch) | $15.50 |
| Register attendee headshots | 900 | $0.00093 / photo (real-time) | $0.84 |
| Daily attendee matching | 2,700 | $0.00062 / search by id | $1.67 |
| Speaker and sponsor searches | 20 | $0.00093 / photo (real-time) | $0.02 |
| Faceprint storage | 75,000 faces + 900 selfies × 1 mo | $6.00 / million stored faces / month | $0.46 |
| **Total** | | | **$18.48** |

That is about $0.021 per enrolled attendee. Billing is per photo processed, never per face: a photo with twelve faces is one charge, and a photo with none is still a processed photo. Rates and calculator: https://sightradar.com/pricing

## Consent and GDPR

Make enrolment a separate, unticked choice in registration, not a line in the event terms, and say how long you keep the headshot and the event collection. Explicit consent is the usual lawful basis for matching faces under GDPR Article 9. Name the event platform and SightRadar as processors in your privacy notice, and delete the collection once photo delivery ends. SightRadar acts as your processor under the Data Processing Agreement (https://sightradar.com/dpa). Our responsible-use posture, deletion modes and the controller/processor split are on https://sightradar.com/trust.

## Further reading

- Build a face recognition photo-sharing platform: https://sightradar.com/blog/build-face-recognition-photo-sharing-platform
- Guide: selfie registration and search-by-id: https://sightradar.com/docs/guides/selfie-registration
- Guide: batch indexing and webhooks: https://sightradar.com/docs/guides/batch-and-webhooks

## Try it

Create a free account at https://sightradar.com/login (no card) or try the live demo at https://sightradar.com/#demo. API reference: https://sightradar.com/docs. All use cases: https://sightradar.com/use-cases