Module: Pdfrb::ImageLoader::JPEG

Defined in:
lib/pdfrb/image_loader/jpeg.rb

Overview

JPEG loader. Parses the SOI/SOFn marker stream to extract width, height, bits-per-component, and number of components. The raw JPEG bytes are stored verbatim with /Filter /DCTDecode — no re-encoding.

Class Method Summary collapse

Class Method Details

.call(document, bytes, **_opts) ⇒ Object 



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# File 'lib/pdfrb/image_loader/jpeg.rb', line 21

def call(document, bytes, **_opts)
  return nil unless bytes.is_a?(::String) && bytes.start_with?(SOI)

  info = parse_header(bytes)
  image = document.add(
    {
      Type: :XObject,
      Subtype: :Image,
      Width: info[:width],
      Height: info[:height],
      BitsPerComponent: info[:precision],
      ColorSpace: info[:color_space],
      Filter: :DCTDecode
    },
    type: Pdfrb::Model::Type::XObjectImage
  )
  image.stream = bytes.b
  image
end