Desempaquetar campos numéricos comprimidos de archivo

[Casimiro Noteví]

Veamos, creo que esto:

Código Delphi [-]
var
  before, after : Word;
 begin
  // Set up out starting number
  before := $3C;      // Hex 3C = 003C in the Word

  // Shift left by 12 will lose the top 12 bits of the Word
  after := before Shl 12;

  ShowMessageFmt('Before : %x',[before]);
  ShowMessageFmt('After shift left  : %x',[after]);

  // Shifting right by 12 will not recover the lost data
  after := after Shr 12;

  ShowMessageFmt('After shift right : %x',[after]);
 end;

Mira los ejemplos de shr y shl en http://www.delphibasics.co.uk