This TYPO3 extension allows setting alternative texts, title labels and a description for images in a filestorage. This can be done via file list backend module or via command on the CLI.
Example metadata labels from AI:
Example backend integration:
Example CLI command:
- To use the extension, you need a Google Gemini API key. You can register for one at https://aistudio.google.com/app/api-keys.
- Alternatively, you can implement your own LLM provider (see Custom LLM Integration below).
composer req in2code/alternative
After that, you have to set some initial configuration in Extension Manager configuration:
| Title | Default value | Description |
|---|---|---|
| setAlternative | 1 | Toggle function: Set a value for alternative text |
| setTitle | 1 | Toggle function: Set a value for image title |
| setDescription | 1 | Toggle function: Set a value for a description |
| showButtonInFileList | 1 | Show or hide button in backend module file list |
| apiKey | - | Google Gemini API key. You can let this value empty and simply use ENV_VAR "GOOGLE_API_KEY" instead if you want to use CI pipelines for this setting |
| limitToLanguages | - | If set, limit to this language identifiers only. Use a commaseparated list of numbers |
| maxLengthTitle | 50 | Maximum number of characters for the title field |
| maxLengthAlternative | 125 | Maximum number of characters for the alternative text field |
| maxLengthDescription | 255 | Maximum number of characters for the description field |
| promptPrefixFile | - | Path to a text file with custom prompt prefix (e.g. EXT:extension/Resources/Private/prompt.txt or fileadmin/promptprefix.txt or /var/www/prompt.txt) |
Note: It's recommended to use ENV vars for in2code/alternative instead of saving the API-Key in Extension Manager configuration
GOOGLE_API_KEY=your_api_key_from_google
# Set metadata for all image files in storage 1
./vendor/bin/typo3 alternative:set "1:/"
# Set metadata for all image files in a subfoler in storage 1 (maybe "fileadmin/in2code/folder/")
./vendor/bin/typo3 alternative:set "1:/in2code/folder/"
# Enforce to set metadata for all image files in storage 1
./vendor/bin/typo3 alternative:set "1:/" 1
Alternative uses a factory pattern to allow custom LLM providers. By default, it uses Google Gemini, but you can easily integrate other AI services (OpenAI, Claude, local models, etc.).
- Create a custom repository class implementing
RepositoryInterface- see example for OpenAI ChatGPT:
<?php
declare(strict_types=1);
namespace Vendor\MyExtension\Domain\Repository\Llm;
use In2code\Alternative\Domain\Repository\Llm\AbstractRepository;
use In2code\Alternative\Domain\Repository\Llm\RepositoryInterface;
use In2code\Alternative\Exception\ApiException;
use In2code\Alternative\Exception\ConfigurationException;
use TYPO3\CMS\Core\Http\RequestFactory;
use TYPO3\CMS\Core\Resource\File;
class ChatGptRepository extends AbstractRepository implements RepositoryInterface
{
private string $apiKey = '';
private string $apiUrl = 'https://api.openai.com/v1/chat/completions';
public function __construct(
protected RequestFactory $requestFactory,
) {
parent::__construct($requestFactory);
$this->apiKey = getenv('OPENAI_API_KEY') ?: '';
}
public function checkApiKey(): void
{
if ($this->apiKey === '') {
throw new ConfigurationException('OpenAI API key not configured', 1735646000);
}
}
public function getApiUrl(): string
{
return $this->apiUrl;
}
/**
* Analyze image and return metadata for all requested languages in one API call
*
* @param File $file
* @param array $languageCodes e.g. ['en', 'de', 'fr']
* @return array e.g. ['en' => ['title' => '...', ...], 'de' => [...], ...]
*/
public function analyzeImageForLanguages(File $file, array $languageCodes): array
{
$this->checkApiKey();
$imageData = base64_encode($file->getContents());
return $this->generateMetadataWithChatGpt($imageData, $file->getMimeType(), $languageCodes);
}
protected function generateMetadataWithChatGpt(string $imageData, string $mimeType, array $languageCodes): array
{
$payload = [
'model' => 'gpt-4o',
'messages' => [
[
'role' => 'user',
'content' => [
['type' => 'text', 'text' => $this->getPrompt($languageCodes)],
[
'type' => 'image_url',
'image_url' => [
'url' => 'data:' . $mimeType . ';base64,' . $imageData,
],
],
],
],
],
'temperature' => 0.1,
'max_tokens' => 2000,
];
$options = [
'headers' => [
'Authorization' => 'Bearer ' . $this->apiKey,
'Content-Type' => 'application/json',
],
'body' => json_encode($payload),
];
$response = $this->requestFactory->request($this->getApiUrl(), $this->requestMethod, $options);
if ($response->getStatusCode() !== 200) {
throw new ApiException(
'Failed to analyze image with ChatGPT: ' . $response->getBody()->getContents(),
1735646001
);
}
$responseData = json_decode($response->getBody()->getContents(), true);
return $this->parseResponse($responseData, $languageCodes);
}
protected function parseResponse(array $responseData, array $languageCodes): array
{
if (isset($responseData['choices'][0]['message']['content']) === false) {
throw new ApiException('Invalid ChatGPT API response structure', 1735646002);
}
$text = $responseData['choices'][0]['message']['content'];
// Extract JSON from markdown code blocks if present
if (preg_match('~```json\s*(\{.*?\})\s*```~s', $text, $matches)) {
$text = $matches[1];
} elseif (preg_match('~```\s*(\{.*?\})\s*```~s', $text, $matches)) {
$text = $matches[1];
}
$data = json_decode($text, true);
if ($data === null) {
throw new ApiException('Could not parse ChatGPT response as JSON', 1735646003);
}
$result = [];
foreach ($languageCodes as $languageCode) {
$languageData = $data[$languageCode] ?? [];
$result[$languageCode] = [
'title' => $languageData['title'] ?? '',
'description' => $languageData['description'] ?? '',
'alternativeText' => $languageData['alternativeText'] ?? '',
];
}
return $result;
}
}
- Register your custom repository in
ext_localconf.php:
<?php
defined('TYPO3') || die();
// Register custom LLM repository
$GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS']['alternative']['llmRepositoryClass']
= \Vendor\MyExtension\Domain\Repository\Llm\ChatGptRepository::class;
Hint: Don't forget to register your Repository in your Services.yaml and flush caches
| Version | Date | State | Description |
|---|---|---|---|
| 4.0.0 !!! | 2026-02-04 | Feature | Performance update for systems with a lot of languages |
| 3.0.1 | 2026-02-02 | Task | Add funding section to composer.json |
| 3.0.0 | 2026-01-28 | Feature | Configure max length, configure a pre-prompt text, some improvements for local development |
| 2.0.0 | 2025-12-31 | Feature | Prepare overruling of the GeminiRepository |
| 1.2.0 | 2025-12-07 | Feature | Support TYPO3 14, use better titles and icons, decrease length for metadata, skip missing images |
| 1.1.0 | 2025-12-04 | Feature | Add ddev as local environment, prevent syntax error in PHP 8.2 |
| 1.0.0 | 2025-12-03 | Task | Initial release of in2code/alternative |
Update to version 4.0.0: If you have implemented your own LLM by extending RepositoryInterface with your own PHP class, you have to adjust your integration with multilanguage support now. See implementation example above.
This repository provides a DDEV-backed development environment. If DDEV is installed, simply run the following commands to quickly set up a local environment with example usages:
ddev startddev initialize
Backend Login:
Username: admin
Password: admin
Installation hint:
- Install ddev before, see: https://ddev.readthedocs.io/en/stable/#installation
- Install git-lfs before, see: https://git-lfs.github.com/
- Add the API key in
.ddev/.envlike
GOOGLE_API_KEY=your_api_key_from_google
| Command | Description |
|---|---|
ddev initialize |
Import test data into ddev (database and configurations) |
ddev typo3 [command] |
Run TYPO3 CLI commands (e.g. ddev typo3 cache:flush) |
ddev createdumpfile |
Create database dump and save to .ddev/data/db.sql.gz |
ddev createfilesarchive |
Create fileadmin archive and save to .ddev/data/fileadmin.tar.gz |