def _plotCoeffs(data, outdir):
    rows = len(data)
    cols = len(data[0])

    ##### Power spectrum ###########
    plt.plot(np.ravel(data))
    plt.title('DWPT coeff')
    plt.xlim(0,rows*cols)
    plt.xlabel('Position')
    plt.ylabel('Frequency')
    plt.savefig(outdir+'_coeff.jpg')
    plt.close()
    plt.close('all')
    plt.gcf().clear()
    ##### Contour ##############
    ax1 = plt.subplot(111)
    ax1.imshow(data, cmap='gray')
    plt.title('dim = '+ str(cols) + 'x' + str(rows))
    plt.savefig(outdir+'_contour.jpg')
    plt.close()
    plt.close('all')
    plt.gcf().clear()