PIL loading single channel for tif image data type - matplotlib

I've a satelite image with tiff file format. When i try to open the file using pil and then print size, I get only one channel:
im = Image.open('1989.tif',mode='r')
print(im.size) -- > (687,1091)
If i try to open with matplotlib, it loads all the channel but I get a blank image when I use imshow( r,g,b values of the images are all zero when I print the values) :
im=plt.imread("1989.tif")
print(im.shape) -- > (687,1091,4)
plt.imshow(im) -- > shows blank image
I don't know how to fix either of them.
Adding the link to the image :
https://drive.google.com/open?id=1uNQxyCplD7rYd_ZWfFntP1bN_Qg49ybU


Your image is an uncompressed 32-bit floating point single channel image. PIL/Pillow seems able to read it fine - it will have problems displaying it, but we can work on that next...
from PIL import Image
import numpy as np
# Load image and make into Numpy array
im = Image.open('a.tif')
n = np.array(im)
# Check max value
print(n.max()) # prints 0.54
# Make an 8-bit version for display
Image.fromarray((n*200).astype(np.uint8)).show()
You can inspect the image with tiffinfo that comes with libtiff:
tiffinfo a.tif
Output
TIFFReadDirectory: Warning, Unknown field with tag 33550 (0x830e) encountered.
TIFFReadDirectory: Warning, Unknown field with tag 33922 (0x8482) encountered.
TIFFReadDirectory: Warning, Unknown field with tag 34735 (0x87af) encountered.
TIFFReadDirectory: Warning, Unknown field with tag 34736 (0x87b0) encountered.
TIFFReadDirectory: Warning, Unknown field with tag 34737 (0x87b1) encountered.
TIFFReadDirectory: Warning, Unknown field with tag 42112 (0xa480) encountered.
TIFFReadDirectory: Warning, Unknown field with tag 42113 (0xa481) encountered.
TIFF Directory at offset 0x8 (8)
Image Width: 1091 Image Length: 687
Tile Width: 128 Tile Length: 128
Bits/Sample: 32
Sample Format: IEEE floating point
Compression Scheme: None
Photometric Interpretation: min-is-black
Samples/Pixel: 1
Planar Configuration: single image plane
Tag 33550: 30.000000,30.000000,0.000000
Tag 33922: 0.000000,0.000000,0.000000,357075.000000,2904735.000000,0.000000
Tag 34735: 1,1,0,16,1024,0,1,1,1025,0,1,1,1026,34737,24,0,2048,0,1,4326,2049,34737,84,24,2050,0,1,6326,2051,0,1,8901,2054,0,1,9102,2055,34736,1,0,2056,0,1,7030,2057,34736,1,1,2059,34736,1,2,2061,34736,1,3,3072,0,1,32646,3073,34737,410,108,3076,0,1,9001
Tag 34736: 0.017453,6378137.000000,298.257224,0.000000
Tag 34737: PCS Name = UTM_Zone_46N|GCS Name = GCS_WGS_1984|Datum = D_WGS_1984|Ellipsoid = WGS_1984|Primem = Greenwich||ESRI PE String = PROJCS["UTM_Zone_46N",GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137.0,298.257223563]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],PARAMETER["False_Easting",500000.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",93.0],PARAMETER["Scale_Factor",0.9996],PARAMETER["Latitude_Of_Origin",0.0],UNIT["Meter",1.0]]|
Tag 42112: <GDALMetadata>
<Item name="STATISTICS_EXCLUDEDVALUES" sample="0"></Item>
<Item name="STATISTICS_MAXIMUM" sample="0">0.53153151273727</Item>
<Item name="STATISTICS_MEAN" sample="0">0.14108245105659</Item>
<Item name="STATISTICS_MINIMUM" sample="0">-0.48148149251938</Item>
<Item name="STATISTICS_SKIPFACTORX" sample="0">1</Item>
<Item name="STATISTICS_SKIPFACTORY" sample="0">1</Item>
<Item name="STATISTICS_STDDEV" sample="0">0.15760411626121</Item>
</GDALMetadata>
Tag 42113: -3.4028234663852886e+38

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