crop_ionograms.py

import numpy as n
import glob
import matplotlib.pyplot as plt
import h5py
import imageio
import chirp_config as cc
import sys
import scipy.constants as c
import os


def create_cropped_ionograms(conf,
                             range_offset=300.0):
    """
    the purpose of this hacked together script is to convert ionograms into format
    suitable for scaling
    """
    print(conf.output_dir)
    fl = glob.glob("%s/*/lfm*.h5" % (conf.output_dir))
    fl.sort()

    max_dB = 30.0
    min_dB = 0.0
    for f in fl:
        print(f)
        h = h5py.File(f, "r")
        ranges = n.copy(h["ranges"])
        freqs = n.copy(h["freqs"])

        t0 = h["t0"].value
        img_fname = "dl_dataset/iono-%d.png" % (t0)
        if os.path.exists(img_fname):
            print("already exists %s. skipping" % (img_fname))
            h.close()
            continue

        dt = (t0 - n.floor(t0))
        dr = dt * c.c / 1e3
        range_gates = dr + 2 * ranges / 1e3
        print(dr)
        ri0 = n.argmin(n.abs(range_gates - range_offset))
        S = n.transpose(n.copy(h["S"].value))
        for fi in range(S.shape[1]):
            noise_floor = n.nanmedian(S[:, fi])
            S[:, fi] = (S[:, fi] - noise_floor) / noise_floor

        #        plt.pcolormesh(freqs,range_gates[ri0:(ri0+200)],10.0*n.log10(S[ri0:(ri0+200)]),vmin=0,vmax=30,cmap="plasma")
        #       plt.show()
        #      if False:
        #         print(h["S"].value.shape)
        #        print(h.keys())
        dB = 10.0 * n.log10(S)
        dB[dB > max_dB] = max_dB
        dB[dB < min_dB] = min_dB
        dB[n.isnan(dB)] = min_dB

        img = dB[(ri0):(ri0 + 200), :]

        img_rgs = ranges[(ri0):(ri0 + 200)][::-1] / 1e3 + range_offset
        ho = h5py.File("dl_dataset/lut.h5", "w")
        ho["img_rgs"] = img_rgs
        ho["img_freqs"] = freqs / 1e6
        ho.close()
        img = img[::-1, :]
        img = n.array(255.0 * img / max_dB, dtype=n.uint8)
        imageio.imwrite(img_fname, img)
        h.close()


if __name__ == "__main__":
    print(sys.argv[1])
    if len(sys.argv) == 2:
        conf = cc.chirp_config(sys.argv[1])
    else:
        conf = cc.chirp_config()
    create_cropped_ionograms(conf)