When converting a document to PDF/A, the following changes are made to a document by default:

  1. Graphics will be converted to a device-independent format. If any device dependent color spaces are used, the corresponding color profile will be embedded.
  2. Non-embedded fonts will be embedded.
  3. Transparency will be removed.
  4. Unsupported annotations (e.g., video, audio, 3D) will be removed.
  5. JavaScript – mostly used in Forms – will be removed.
  6. Form fields will be flattened, except for signature fields.
  7. Embedded files and external hyperlinks will be removed.

jPDFPreflight library offers the PDFConversionOptions class to control some of the conversion options:

// Set conversion options
PDFAConversionOptions options = (PDFAConversionOptions) profile.getConversionOptions();
options.setTransparency(PDFAConversionOptions.OPTION_WARN);
options.setUnsupportedAnnotations(PDFAConversionOptions.OPTION_DELETE);
options.setSignatureFields(PDFAConversionOptions.OPTION_FLATTEN);
options.setEmbeddedFiles(PDFAConversionOptions.OPTION_DELETE);