TJPEGDefaults = record
  CompressionQuality: TJPEGQualityRange;
  Grayscale: Boolean;
  Performance: TJPEGPerformance;
  PixelFormat: TJPEGPixelFormat;
  ProgressiveDisplay: Boolean;
  ProgressiveEncoding: Boolean;
  Scale: TJPEGScale;
  Smoothing: Boolean;
end;

struct TJPEGDefaults {
  TJPEGQualityRange CompressionQuality;
  Boolean Grayscale;
  TJPEGPerformance Performance;
  TJPEGPixelFormat PixelFormat;
  Boolean ProgressiveDisplay;
  Boolean ProgressiveEncoding;
  TJPEGScale Scale;
  Boolean Smoothing;
};