{ Conversion d'un texte vers sa représentation binaire
}
function StrToStrBin(const S: string): string;
var pOutput : pChar;
    pInput : ^byte;
    N, LenInput : integer;
const
  AtBin : array[boolean] of char = '01';
begin
  LenInput := Length(S);
  SetLength(Result, LenInput shl 3);
  pInput := @S[1];
  pOutput := pChar(result);
  for N := 1 to LenInput do
  begin
    pOutput[0] := AtBin[(pInput^ and $80) = $80];
    pOutput[1] := AtBin[(pInput^ and $40) = $40];
    pOutput[2] := AtBin[(pInput^ and $20) = $20];
    pOutput[3] := AtBin[(pInput^ and $10) = $10];
    pOutput[4] := AtBin[(pInput^ and $08) = $08];
    pOutput[5] := AtBin[(pInput^ and $04) = $04];
    pOutput[6] := AtBin[(pInput^ and $02) = $02];
    pOutput[7] := AtBin[(pInput^ and $01) = $01];
    inc(pOutput,8);
    inc(pInput);
  end;
end;

{ Conversion d'une représentation binaire en texte.
}
function StrBinToStr(const S: string): string;
var pInput : PChar;
    pOutput: ^Byte;
    N, LenInput: integer;
const
  AtBin : array['0'..'1'] of byte = (0,1);
begin
  LenInput := Length(S);
  SetLength(result, LenInput shr 3);
  LenInput := Length(result);
  pInput := PChar(S);
  pOutput := @result[1];
  for N := 1 to LenInput do
  begin
    pOutput^ := 0;
    pOutput^ := byte( (AtBin[pInput[0]] shl 7) or
                      (AtBin[pInput[1]] shl 6) or
                      (AtBin[pInput[2]] shl 5) or
                      (AtBin[pInput[3]] shl 4) or
                      (AtBin[pInput[4]] shl 3) or
                      (AtBin[pInput[5]] shl 2) or
                      (AtBin[pInput[6]] shl 1) or
                       AtBin[pInput[7]]
                  );
    inc(pInput, 8);
    inc(pOutput);
  end;
end;