Converting JSV back to byte[] using ServiceStack.Text

gistfile1.cs

public override ClientePessoaJuridica Save(string jsv)
        {
            ClientePessoaJuridica model = jsv.FromJsv<ClientePessoaJuridica>();
            var lastindex = 0;
            var startmark = "Imagem:";
            foreach (var dig in model.Digitalizacoes)
            {
                var start = jsv.IndexOf(startmark, lastindex) + startmark.Length;
                var end = lastindex = jsv.IndexOf(",", start);
                dig.Imagem = Convert.FromBase64String(jsv.Substring(start, end - start).Replace(" ", "+"));
            }
            return Save(model);
        }