text: "use strict";
  Object.defineProperty(exports, "__esModule", { value: true });
  const pngSignature = 'PNG\r\n\x1a\n';
  const pngImageHeaderChunkName = 'IHDR';
  // Used to detect "fried" png's: http://www.jongware.com/pngdefry.html
  const pngFriedChunkName = 'CgBI';
  exports.PNG = {
      validate(buffer) {
          if (pngSignature === buffer.toString('ascii', 1, 8)) {
              let chunkName = buffer.toString('ascii', 12, 16);
              if (chunkName === pngFriedChunkName) {
                  chunkName = buffer.toString('ascii', 28, 32);
              }
              if (chunkName !== pngImageHeaderChunkName) {
                  throw new TypeError('Invalid PNG');
              }
              return true;
          }
          return false;
      },
      calculate(buffer) {
          if (buffer.toString('ascii', 12, 16) === pngFriedChunkName) {
              return {
                  height: buffer.readUInt32BE(36),
                  width: buffer.readUInt32BE(32)
              };
          }
          return {
              height: buffer.readUInt32BE(20),
              width: buffer.readUInt32BE(16)
          };
      }
  };
  