White nodata values instead of black

Question

I have a problem. I cut a map on tiles using gdal_csharp.dll library (working on gdal_retile.py script rewritten into C#). Everything works fine except one case. When I cut areas with nodata values (tiles on the borders) and save them as JPEG files, the nodata areas are black (and I need them white) - example tile included below. I tried to use tBand.SetNoDataValue(0); but sometimes black not-nodata values (e.g. city names, road names, etc.) contain white dots...

Example tiles: Tile no1 and Tile no2

I don't know how to set SetNoDataValue(/* what to write in here? */)... Maybe there's the other way to solve this problem?

Here's my method:

private void CreatePyramidTile(MosaicInfo levelMosaicInfo, int offsetX, int offsetY, int width, int height, string tileName, DataSource ogrds)
{
    double sx = levelMosaicInfo.ScaleX * _scaleFactor;
    double sy = levelMosaicInfo.ScaleY * _scaleFactor;

    AffineTransformDecorator dec =
        new AffineTransformDecorator(new[]
                                         {
                                             levelMosaicInfo.Ulx + offsetX*sx, sx, 0,
                                             levelMosaicInfo.Uly + offsetY*sy, 0, sy
                                         });

    Dataset sFh = levelMosaicInfo.GetDataSet((int) Math.Round(dec.Ulx),
                                             (int) Math.Round((dec.Uly + height*dec.ScaleY)),
                                             (int) Math.Round((dec.Ulx + width*dec.ScaleX)),
                                             (int) Math.Round(dec.Uly));

    if (sFh == null)
    {
        return;
    }

    if (ogrds != null)
    {
        var points = dec.PointsFor(width, height);
        AddFeature(ogrds, tileName, points);
    }

    DataType bt;
    if (_bandType == DataType.GDT_Unknown)
    {
        bt = levelMosaicInfo.BandType;
    }
    else
    {
        bt = _bandType;
    }

    double[] geotransform = { dec.Ulx, dec.ScaleX, 0, dec.Uly, 0, dec.ScaleY };
    int bands = levelMosaicInfo.Bands;

    Dataset tFh;
    if (_memDriver == null)
    {
        tFh = _driver.Create(tileName, width, height, bands, bt, _createOptions.ToArray());
    }
    else
    {
        tFh = _memDriver.Create(tileName, width, height, bands, bt, _createOptions.ToArray());
    }

    if (tFh == null)
    {
        throw new Exception("Creation failed, terminating gdal_tile.");
    }

    tFh.SetGeoTransform(geotransform);
    tFh.SetProjection(levelMosaicInfo.Projection);
// I think, the problem occurs in this loop; I tried to set nodata values
    for (int band = 1; band < bands + 1; band++)
    {
        Band tBand = tFh.GetRasterBand(band);

        if (levelMosaicInfo.Ct != null)
        {
            tBand.SetRasterColorTable(levelMosaicInfo.Ct);
        }
        tBand.SetRasterColorInterpretation(levelMosaicInfo.Ci[band - 1]);
//                tBand.SetNoDataValue(0);
    }

    var res = Gdal.ReprojectImage(sFh, tFh, null, null, _resamplingMethod, 0, 0, null, null);

    if (res != 0)
    {
        throw new Exception("Reprojection failed for " + tileName + ", error " + res + ".");
    }

    levelMosaicInfo.CloseDataSet(ref sFh);

    if (_memDriver != null)
    {
        Dataset ttFh = _driver.CreateCopy(tileName, tFh, 0, _createOptions.ToArray(), null, null);
        ttFh.Dispose();
    }

    tFh.Dispose();
}