An example of how to use Jimp to read a base64 image string, resize, removeExif data, then return as an image buffer.

jimp-example.js

let imageBuffer = Buffer.from(body.profilePicture.split(',')[1], 'base64');
console.log(imageBuffer);

Jimp.read(imageBuffer, function(err, image) {
  if (err) {
    context.done(err,
      prepareErrorResponse(response, 'Unable to remove EXIF data from profile picture'));
    }
    console.log('before transform: ', image);
    image = image.resize(400, 400).exifRotate((err, exifRotatedData) => {
      if (err) {
        console.log(err);
        context.done(err,
          prepareErrorResponse(response, 'Unable to rotate profile picture'));
        }
        console.log('data after exif: ', exifRotatedData);
        console.log('image after exif: ', image);
        image.getBuffer(image.getMIME(), function(err, buffer) {
          if (err) {
            console.log(err);
            context.done(err,
              prepareErrorResponse(response, 'Unable to get buffer for profile picture'));
            }
            console.log('after transform: ', buffer);
            // Setup s3 bucket params to save the profile picture
            var params = {
              Bucket: process.env.ProviderPhotoBucket,
              Key: 'public/' + body.fileName,
              Body: buffer
            };
            console.log(params);
            // Set/update the Agent's profile picture in s3 bucket
            s3.putObject(params, function(err, object) {
              if (err) {
                console.log(err);
                context.done(err,
                  prepareErrorResponse(response, 'Unable to upload profile picture'));
                }
                else {
                  // Profile picture was set/updated successfully
                  let fileName = body.fileName;
                  let userId = event.requestContext.identity.cognitoIdentityId;
                  
                  // Update Agent's database item to reflect the url of
                  // the newly updated profile picture in s3
                  updateDynamoUser({ profilePictureTag: JSON.parse(object.ETag), profilePicture: fileName, userId: userId }, Table, context, response, userValidator);
                }
              });
            });
          });
        });