Image Thumbnails Generation Implementation for Website

Image Thumbnails Generation

Thumbnail generation transforms uploaded images into multiple sizes for different contexts (list, card, full-size view) without losing original.

Laravel: Intervention Image + queue

// Model with automatic thumbnail generation
class Image extends Model
{
    const SIZES = [
        'thumb'  => [200, 200],
        'medium' => [600, 400],
        'large'  => [1200, 800],
    ];
}

// Job for async generation
class GenerateImageThumbnails implements ShouldQueue
{
    use Dispatchable, InteractsWithQueue, Queueable;

    public function __construct(private Image $image) {}

    public function handle(): void
    {
        $originalPath = Storage::disk('s3')->path($this->image->path);
        $img = \Intervention\Image\Facades\Image::make($originalPath);

        foreach (Image::SIZES as $size => [$width, $height]) {
            $resized = clone $img;
            $resized->fit($width, $height);  // crop to center

            $thumbPath = str_replace('original/', "{$size}/", $this->image->path);
            Storage::disk('s3')->put($thumbPath, $resized->encode('webp', 85)->__toString());
        }

        $this->image->update(['processed' => true]);
    }
}

// Upload controller
public function store(Request $request): JsonResponse
{
    $path = Storage::disk('s3')->putFile('original', $request->file('image'));

    $image = Image::create([
        'path'       => $path,
        'user_id'    => auth()->id(),
        'processed'  => false,
    ]);

    GenerateImageThumbnails::dispatch($image);

    return response()->json(['id' => $image->id]);
}

Node.js: Sharp

Sharp is the fastest Node.js image processing library (based on libvips).

import sharp from 'sharp';
import { S3Client, GetObjectCommand, PutObjectCommand } from '@aws-sdk/client-s3';

const SIZES = {
  thumb:  { width: 200, height: 200 },
  medium: { width: 600, height: 400 },
  large:  { width: 1200, height: 800 },
} as const;

async function generateThumbnails(s3Key: string): Promise<Record<string, string>> {
  const s3 = new S3Client({ region: 'eu-west-1' });

  // Download original
  const { Body } = await s3.send(new GetObjectCommand({
    Bucket: process.env.S3_BUCKET!,
    Key: s3Key,
  }));

  const buffer = Buffer.from(await (Body as any).transformToByteArray());

  const results: Record<string, string> = {};

  await Promise.all(
    Object.entries(SIZES).map(async ([name, { width, height }]) => {
      const thumbnail = await sharp(buffer)
        .resize(width, height, { fit: 'cover', position: 'centre' })
        .webp({ quality: 85 })
        .toBuffer();

      const thumbKey = s3Key.replace('original/', `${name}/`).replace(/\.[^.]+$/, '.webp');

      await s3.send(new PutObjectCommand({
        Bucket: process.env.S3_BUCKET!,
        Key: thumbKey,
        Body: thumbnail,
        ContentType: 'image/webp',
        CacheControl: 'public, max-age=31536000',
      }));

      results[name] = thumbKey;
    })
  );

  return results;
}

Lazy generation via Glide (PHP)

Glide generates thumbnails on demand with signed URLs:

// Image route
Route::get('/img/{path}', function (Request $request, string $path) {
    $server = League\Glide\ServerFactory::create([
        'source'    => Storage::disk('s3')->getDriver(),
        'cache'     => Storage::disk('local')->getDriver(),
        'cache_path_prefix' => '.cache',
        'base_url'  => '/img',
        'max_image_size' => 2000 * 2000,
    ]);

    // Validate signed URL
    League\Glide\Signatures\SignatureFactory::create(config('app.key'))
        ->validateRequest('/img/' . $path, $request->all());

    return $server->getImageResponse($path, $request->all());
})->where('path', '.*');

// Generate signed URL
$url = (new League\Glide\Urls\UrlBuilderFactory)
    ->create('/img', config('app.key'))
    ->getUrl('uploads/photo.jpg', ['w' => 400, 'h' => 300, 'fit' => 'crop']);

Formats and optimization

// Choose format by browser support
const output = sharp(buffer)
  .resize(800)
  .toFormat(supportsAvif ? 'avif' : supportsWebp ? 'webp' : 'jpeg', {
    quality: supportsAvif ? 60 : supportsWebp ? 80 : 85,
  });

AVIF gives 50% savings compared to JPEG at same quality. WebP is supported by all modern browsers. For maximum compatibility use <picture> with multiple formats.

Implementation timeline

Thumbnail generation in queue (Laravel Job or BullMQ Worker) with S3 storage: 2–3 days. With lazy generation via Glide and CDN caching: 3–4 days.