function _createInputDescriptor (input, inputOptions, containerOptions) {
  const inputDescriptor = {
    autoOrient: false,
    failOn: 'warning',
    limitInputPixels: Math.pow(0x3FFF, 2),
    ignoreIcc: false,
    unlimited: false,
    sequentialRead: true
  };
  if (is.string(input)) {
    // filesystem
    inputDescriptor.file = input;
  } else if (is.buffer(input)) {
    // Buffer
    if (input.length === 0) {
      throw Error('Input Buffer is empty');
    }
    inputDescriptor.buffer = input;
  } else if (is.arrayBuffer(input)) {
    if (input.byteLength === 0) {
      throw Error('Input bit Array is empty');
    }
    inputDescriptor.buffer = Buffer.from(input, 0, input.byteLength);
  } else if (is.typedArray(input)) {
    if (input.length === 0) {
      throw Error('Input Bit Array is empty');
    }
    inputDescriptor.buffer = Buffer.from(input.buffer, input.byteOffset, input.byteLength);
  } else if (is.plainObject(input) && !is.defined(inputOptions)) {
    // Plain Object descriptor, e.g. create
    inputOptions = input;
    if (_inputOptionsFromObject(inputOptions)) {
      // Stream with options
      inputDescriptor.buffer = [];
    }
  } else if (!is.defined(input) && !is.defined(inputOptions) && is.object(containerOptions) && containerOptions.allowStream) {
    // Stream without options
    inputDescriptor.buffer = [];
  } else if (Array.isArray(input)) {
    if (input.length > 1) {
      // Join images together
      if (!this.options.joining) {
        this.options.joining = true;
        this.options.join = input.map(i => this._createInputDescriptor(i));
      } else {
        throw new Error('Recursive join is unsupported');
      }
    } else {
      throw new Error('Expected at least two images to join');
    }
  } else {
    throw new Error(`Unsupported input '${input}' of type ${typeof input}${
      is.defined(inputOptions) ? ` when also providing options of type ${typeof inputOptions}` : ''
    }`);
  }
  if (is.object(inputOptions)) {
    // Deprecated: failOnError
    if (is.defined(inputOptions.failOnError)) {
      if (is.bool(inputOptions.failOnError)) {
        inputDescriptor.failOn = inputOptions.failOnError ? 'warning' : 'none';
      } else {
        throw is.invalidParameterError('failOnError', 'boolean', inputOptions.failOnError);
      }
    }
    // failOn
    if (is.defined(inputOptions.failOn)) {
      if (is.string(inputOptions.failOn) && is.inArray(inputOptions.failOn, ['none', 'truncated', 'error', 'warning'])) {
        inputDescriptor.failOn = inputOptions.failOn;
      } else {
        throw is.invalidParameterError('failOn', 'one of: none, truncated, error, warning', inputOptions.failOn);
      }
    }
    // autoOrient
    if (is.defined(inputOptions.autoOrient)) {
      if (is.bool(inputOptions.autoOrient)) {
        inputDescriptor.autoOrient = inputOptions.autoOrient;
      } else {
        throw is.invalidParameterError('autoOrient', 'boolean', inputOptions.autoOrient);
      }
    }
    // Density
    if (is.defined(inputOptions.density)) {
      if (is.inRange(inputOptions.density, 1, 100000)) {
        inputDescriptor.density = inputOptions.density;
      } else {
        throw is.invalidParameterError('density', 'number between 1 and 100000', inputOptions.density);
      }
    }
    // Ignore embeddded ICC profile
    if (is.defined(inputOptions.ignoreIcc)) {
      if (is.bool(inputOptions.ignoreIcc)) {
        inputDescriptor.ignoreIcc = inputOptions.ignoreIcc;
      } else {
        throw is.invalidParameterError('ignoreIcc', 'boolean', inputOptions.ignoreIcc);
      }
    }
    // limitInputPixels
    if (is.defined(inputOptions.limitInputPixels)) {
      if (is.bool(inputOptions.limitInputPixels)) {
        inputDescriptor.limitInputPixels = inputOptions.limitInputPixels
          ? Math.pow(0x3FFF, 2)
          : 0;
      } else if (is.integer(inputOptions.limitInputPixels) && is.inRange(inputOptions.limitInputPixels, 0, Number.MAX_SAFE_INTEGER)) {
        inputDescriptor.limitInputPixels = inputOptions.limitInputPixels;
      } else {
        throw is.invalidParameterError('limitInputPixels', 'positive integer', inputOptions.limitInputPixels);
      }
    }
    // unlimited
    if (is.defined(inputOptions.unlimited)) {
      if (is.bool(inputOptions.unlimited)) {
        inputDescriptor.unlimited = inputOptions.unlimited;
      } else {
        throw is.invalidParameterError('unlimited', 'boolean', inputOptions.unlimited);
      }
    }
    // sequentialRead
    if (is.defined(inputOptions.sequentialRead)) {
      if (is.bool(inputOptions.sequentialRead)) {
        inputDescriptor.sequentialRead = inputOptions.sequentialRead;
      } else {
        throw is.invalidParameterError('sequentialRead', 'boolean', inputOptions.sequentialRead);
      }
    }
    // Raw pixel input
    if (is.defined(inputOptions.raw)) {
      if (
        is.object(inputOptions.raw) &&
        is.integer(inputOptions.raw.width) && inputOptions.raw.width > 0 &&
        is.integer(inputOptions.raw.height) && inputOptions.raw.height > 0 &&
        is.integer(inputOptions.raw.channels) && is.inRange(inputOptions.raw.channels, 1, 4)
      ) {
        inputDescriptor.rawWidth = inputOptions.raw.width;
        inputDescriptor.rawHeight = inputOptions.raw.height;
        inputDescriptor.rawChannels = inputOptions.raw.channels;
        inputDescriptor.rawPremultiplied = !!inputOptions.raw.premultiplied;

        switch (input.constructor) {
          case Uint8Array:
          case Uint8ClampedArray:
            inputDescriptor.rawDepth = 'uchar';
            break;
          case Int8Array:
            inputDescriptor.rawDepth = 'char';
            break;
          case Uint16Array:
            inputDescriptor.rawDepth = 'ushort';
            break;
          case Int16Array:
            inputDescriptor.rawDepth = 'short';
            break;
          case Uint32Array:
            inputDescriptor.rawDepth = 'uint';
            break;
          case Int32Array:
            inputDescriptor.rawDepth = 'int';
            break;
          case Float32Array:
            inputDescriptor.rawDepth = 'float';
            break;
          case Float64Array:
            inputDescriptor.rawDepth = 'double';
            break;
          default:
            inputDescriptor.rawDepth = 'uchar';
            break;
        }
      } else {
        throw new Error('Expected width, height and channels for raw pixel input');
      }
    }
    // Multi-page input (GIF, TIFF, PDF)
    if (is.defined(inputOptions.animated)) {
      if (is.bool(inputOptions.animated)) {
        inputDescriptor.pages = inputOptions.animated ? -1 : 1;
      } else {
        throw is.invalidParameterError('animated', 'boolean', inputOptions.animated);
      }
    }
    if (is.defined(inputOptions.pages)) {
      if (is.integer(inputOptions.pages) && is.inRange(inputOptions.pages, -1, 100000)) {
        inputDescriptor.pages = inputOptions.pages;
      } else {
        throw is.invalidParameterError('pages', 'integer between -1 and 100000', inputOptions.pages);
      }
    }
    if (is.defined(inputOptions.page)) {
      if (is.integer(inputOptions.page) && is.inRange(inputOptions.page, 0, 100000)) {
        inputDescriptor.page = inputOptions.page;
      } else {
        throw is.invalidParameterError('page', 'integer between 0 and 100000', inputOptions.page);
      }
    }
    // Multi-level input (OpenSlide)
    if (is.defined(inputOptions.level)) {
      if (is.integer(inputOptions.level) && is.inRange(inputOptions.level, 0, 256)) {
        inputDescriptor.level = inputOptions.level;
      } else {
        throw is.invalidParameterError('level', 'integer between 0 and 256', inputOptions.level);
      }
    }
    // Sub Image File Directory (TIFF)
    if (is.defined(inputOptions.subifd)) {
      if (is.integer(inputOptions.subifd) && is.inRange(inputOptions.subifd, -1, 100000)) {
        inputDescriptor.subifd = inputOptions.subifd;
      } else {
        throw is.invalidParameterError('subifd', 'integer between -1 and 100000', inputOptions.subifd);
      }
    }
    // PDF background colour
    if (is.defined(inputOptions.pdfBackground)) {
      inputDescriptor.pdfBackground = this._getBackgroundColourOption(inputOptions.pdfBackground);
    }
    // JP2 oneshot
    if (is.defined(inputOptions.jp2Oneshot)) {
      if (is.bool(inputOptions.jp2Oneshot)) {
        inputDescriptor.jp2Oneshot = inputOptions.jp2Oneshot;
      } else {
        throw is.invalidParameterError('jp2Oneshot', 'boolean', inputOptions.jp2Oneshot);
      }
    }
    // Create new image
    if (is.defined(inputOptions.create)) {
      if (
        is.object(inputOptions.create) &&
        is.integer(inputOptions.create.width) && inputOptions.create.width > 0 &&
        is.integer(inputOptions.create.height) && inputOptions.create.height > 0 &&
        is.integer(inputOptions.create.channels)
      ) {
        inputDescriptor.createWidth = inputOptions.create.width;
        inputDescriptor.createHeight = inputOptions.create.height;
        inputDescriptor.createChannels = inputOptions.create.channels;
        // Noise
        if (is.defined(inputOptions.create.noise)) {
          if (!is.object(inputOptions.create.noise)) {
            throw new Error('Expected noise to be an object');
          }
          if (!is.inArray(inputOptions.create.noise.type, ['gaussian'])) {
            throw new Error('Only gaussian noise is supported at the moment');
          }
          if (!is.inRange(inputOptions.create.channels, 1, 4)) {
            throw is.invalidParameterError('create.channels', 'number between 1 and 4', inputOptions.create.channels);
          }
          inputDescriptor.createNoiseType = inputOptions.create.noise.type;
          if (is.number(inputOptions.create.noise.mean) && is.inRange(inputOptions.create.noise.mean, 0, 10000)) {
            inputDescriptor.createNoiseMean = inputOptions.create.noise.mean;
          } else {
            throw is.invalidParameterError('create.noise.mean', 'number between 0 and 10000', inputOptions.create.noise.mean);
          }
          if (is.number(inputOptions.create.noise.sigma) && is.inRange(inputOptions.create.noise.sigma, 0, 10000)) {
            inputDescriptor.createNoiseSigma = inputOptions.create.noise.sigma;
          } else {
            throw is.invalidParameterError('create.noise.sigma', 'number between 0 and 10000', inputOptions.create.noise.sigma);
          }
        } else if (is.defined(inputOptions.create.background)) {
          if (!is.inRange(inputOptions.create.channels, 3, 4)) {
            throw is.invalidParameterError('create.channels', 'number between 3 and 4', inputOptions.create.channels);
          }
          inputDescriptor.createBackground = this._getBackgroundColourOption(inputOptions.create.background);
        } else {
          throw new Error('Expected valid noise or background to create a new input image');
        }
        delete inputDescriptor.buffer;
      } else {
        throw new Error('Expected valid width, height and channels to create a new input image');
      }
    }
    // Create a new image with text
    if (is.defined(inputOptions.text)) {
      if (is.object(inputOptions.text) && is.string(inputOptions.text.text)) {
        inputDescriptor.textValue = inputOptions.text.text;
        if (is.defined(inputOptions.text.height) && is.defined(inputOptions.text.dpi)) {
          throw new Error('Expected only one of dpi or height');
        }
        if (is.defined(inputOptions.text.font)) {
          if (is.string(inputOptions.text.font)) {
            inputDescriptor.textFont = inputOptions.text.font;
          } else {
            throw is.invalidParameterError('text.font', 'string', inputOptions.text.font);
          }
        }
        if (is.defined(inputOptions.text.fontfile)) {
          if (is.string(inputOptions.text.fontfile)) {
            inputDescriptor.textFontfile = inputOptions.text.fontfile;
          } else {
            throw is.invalidParameterError('text.fontfile', 'string', inputOptions.text.fontfile);
          }
        }
        if (is.defined(inputOptions.text.width)) {
          if (is.integer(inputOptions.text.width) && inputOptions.text.width > 0) {
            inputDescriptor.textWidth = inputOptions.text.width;
          } else {
            throw is.invalidParameterError('text.width', 'positive integer', inputOptions.text.width);
          }
        }
        if (is.defined(inputOptions.text.height)) {
          if (is.integer(inputOptions.text.height) && inputOptions.text.height > 0) {
            inputDescriptor.textHeight = inputOptions.text.height;
          } else {
            throw is.invalidParameterError('text.height', 'positive integer', inputOptions.text.height);
          }
        }
        if (is.defined(inputOptions.text.align)) {
          if (is.string(inputOptions.text.align) && is.string(this.constructor.align[inputOptions.text.align])) {
            inputDescriptor.textAlign = this.constructor.align[inputOptions.text.align];
          } else {
            throw is.invalidParameterError('text.align', 'valid alignment', inputOptions.text.align);
          }
        }
        if (is.defined(inputOptions.text.justify)) {
          if (is.bool(inputOptions.text.justify)) {
            inputDescriptor.textJustify = inputOptions.text.justify;
          } else {
            throw is.invalidParameterError('text.justify', 'boolean', inputOptions.text.justify);
          }
        }
        if (is.defined(inputOptions.text.dpi)) {
          if (is.integer(inputOptions.text.dpi) && is.inRange(inputOptions.text.dpi, 1, 1000000)) {
            inputDescriptor.textDpi = inputOptions.text.dpi;
          } else {
            throw is.invalidParameterError('text.dpi', 'integer between 1 and 1000000', inputOptions.text.dpi);
          }
        }
        if (is.defined(inputOptions.text.rgba)) {
          if (is.bool(inputOptions.text.rgba)) {
            inputDescriptor.textRgba = inputOptions.text.rgba;
          } else {
            throw is.invalidParameterError('text.rgba', 'bool', inputOptions.text.rgba);
          }
        }
        if (is.defined(inputOptions.text.spacing)) {
          if (is.integer(inputOptions.text.spacing) && is.inRange(inputOptions.text.spacing, -1000000, 1000000)) {
            inputDescriptor.textSpacing = inputOptions.text.spacing;
          } else {
            throw is.invalidParameterError('text.spacing', 'integer between -1000000 and 1000000', inputOptions.text.spacing);
          }
        }
        if (is.defined(inputOptions.text.wrap)) {
          if (is.string(inputOptions.text.wrap) && is.inArray(inputOptions.text.wrap, ['word', 'char', 'word-char', 'none'])) {
            inputDescriptor.textWrap = inputOptions.text.wrap;
          } else {
            throw is.invalidParameterError('text.wrap', 'one of: word, char, word-char, none', inputOptions.text.wrap);
          }
        }
        delete inputDescriptor.buffer;
      } else {
        throw new Error('Expected a valid string to create an image with text.');
      }
    }
    // Join images together
    if (is.defined(inputOptions.join)) {
      if (is.defined(this.options.join)) {
        if (is.defined(inputOptions.join.animated)) {
          if (is.bool(inputOptions.join.animated)) {
            inputDescriptor.joinAnimated = inputOptions.join.animated;
          } else {
            throw is.invalidParameterError('join.animated', 'boolean', inputOptions.join.animated);
          }
        }
        if (is.defined(inputOptions.join.across)) {
          if (is.integer(inputOptions.join.across) && is.inRange(inputOptions.join.across, 1, 1000000)) {
            inputDescriptor.joinAcross = inputOptions.join.across;
          } else {
            throw is.invalidParameterError('join.across', 'integer between 1 and 100000', inputOptions.join.across);
          }
        }
        if (is.defined(inputOptions.join.shim)) {
          if (is.integer(inputOptions.join.shim) && is.inRange(inputOptions.join.shim, 0, 1000000)) {
            inputDescriptor.joinShim = inputOptions.join.shim;
          } else {
            throw is.invalidParameterError('join.shim', 'integer between 0 and 100000', inputOptions.join.shim);
          }
        }
        if (is.defined(inputOptions.join.background)) {
          inputDescriptor.joinBackground = this._getBackgroundColourOption(inputOptions.join.background);
        }
        if (is.defined(inputOptions.join.halign)) {
          if (is.string(inputOptions.join.halign) && is.string(this.constructor.align[inputOptions.join.halign])) {
            inputDescriptor.joinHalign = this.constructor.align[inputOptions.join.halign];
          } else {
            throw is.invalidParameterError('join.halign', 'valid alignment', inputOptions.join.halign);
          }
        }
        if (is.defined(inputOptions.join.valign)) {
          if (is.string(inputOptions.join.valign) && is.string(this.constructor.align[inputOptions.join.valign])) {
            inputDescriptor.joinValign = this.constructor.align[inputOptions.join.valign];
          } else {
            throw is.invalidParameterError('join.valign', 'valid alignment', inputOptions.join.valign);
          }
        }
      } else {
        throw new Error('Expected input to be an array of images to join');
      }
    }
  } else if (is.defined(inputOptions)) {
    throw new Error('Invalid input options ' + inputOptions);
  }
  return inputDescriptor;
}
Create Object containing input and input-related options.
@private