/image-resizer-lambda

Primary LanguageGo

image-resizer-lambda

Dynamic image resizing using AWS Cloudfront, API Gateway, Lambda, and S3.

This is more of a proof of concept at this point than production ready software.

Usage

Lambda Event

The event object must always contain a key property, which must map exactly to a key for an image in the target s3 bucket.

In addition to the key property, the Lambda function expects the event object to contain any number the following properties:

  • maxWidth: Resizes the image to the desired width, maintaining the aspect ratio.
  • maxHeight: Resizes the image to the desired height, maintaining the aspect ratio.
  • format: specifies the desired output format, can be jpeg or png.

If both maxWidth and maxHeight are specified, the image is resized such that the aspect ratio is preserved and the resulting width and height are not greater than the values specified.

Lambda Configuration

The Lambda function can also be configured through the following environment variables.

  • RESIZE_STRATEGY: Can be one of nearest-neighbor, bilinear, bicubic, mitchell-netravali, lanczos2, lanczos3.
  • JPEG_COMPRESSION: The compression level for jpeg formats, from 0-100.
  • PNG_COMPRESSION: The compression level for png formats, can be one of default, none, best-speed, best-compression.
  • S3_BUCKET: The name of the s3 bucket to read from.