read-msh-file.py

# coding: utf-8
# In[1]:
# In[7]:

import struct
import numpy as np
from scipy.misc.pilutil import toimage
from PIL import Image


filename = 'mesh.msh'
f = open(filename, 'rb')


hdr = struct.unpack('BBBB', f.read(4))
assert hdr == (0,0,0,2), "no header found"

header2 = struct.unpack('cccccccc', f.read(8))
print "".join(reversed(header2))

header2000 = struct.unpack('BBBB', f.read(4))
print header2000

w = struct.unpack('i', f.read(4))[0]
h = struct.unpack('i', f.read(4))[0]

print ''
print "Width: {} Height: {}".format(w,h)

hzero = struct.unpack('d', f.read(8))

## read image data

length = w*h
dx_arr = np.zeros(length, np.float32)
dy_arr = np.zeros(length, np.float32)

for idx in range(0, length):
    dx_arr[idx] = struct.unpack('f', f.read(4))[0]
    dy_arr[idx] = struct.unpack('f', f.read(4))[0]
    


dx_arr = dx_arr.reshape(h,w)
dy_arr = dy_arr.reshape(h,w)


# In[6]:

### Visualize as RGB image / save to jpg #####

arr_rgb = np.zeros((h,w,3), np.uint8)

scale = 10

arr_rgb[:,:,0] = np.round(np.clip(128.0 + scale * dx_arr, 0, 255))
arr_rgb[:,:,1] = np.round(np.clip(128.0 + scale * dy_arr, 0, 255))

print arr_rgb.max(), arr_rgb.min()

imshow(arr_rgb)


# In[4]:

image = toimage(arr_rgb)
filename = 'out.jpg'
image = image.resize((128, 128), Image.BICUBIC)
image.save(filename, 'JPEG', quality=100)