Code for changing multiple .img files into .png, then into numpy array - numpy

I'm doing a convolutional neural network classification and currently all my tiles are in .img format (thanks ArcMap). I know I need to get them in .png format, but haven't found code that could convert a whole folder of them. Is that doable?
Eventually I also need to get all those .pngs into a numpy array. I found basic code that will do it for just .png, but is there a way to convert the whole folder at once?
Thanks everyone!

Yes it is doable, just use Python Pil! and loop over all files in the folder with glob.
Some example code:
import os
from PIL import Image
import glob
counter = 0
for image in glob.glob("/Users/Testfolder/*.jpg"):
counter = counter + 1
img = Image.open(image)
img.save('/Users/Testfolder/' + (str(counter)+'img.png'))

Related

Image as array in pandas dataframe

Images in PNG format in a variable (as array) are not being displayed in pandas dataframe.
The command lines:
display(HTML('df.html', df.to_html(escape=False ,formatters=format_dict)))
or
display(HTML(df.to_html(escape=False ,formatters=format_dict)))
should run using the following IPython packages
from IPython.display import display,HTML
from IPython.display import IFrame
However, these commands can only concatenate str (not "PngImageFile") to str. Also, I found in the stack overflow (How to write PNG image to string with the PIL?) that it is possible to solve this issue using a png file, but I need to add this png file into a pandas dataframe that does not work as well because a PngImageFile object is not callable.
How can I solve this issue?
Here is an example:
https://colab.research.google.com/drive/163jW-GoXKW4TckuIVK3_wjXB9wP11u0g?usp=sharing

How to convert the .wav file to tfrecord file?

I am new in the tensorflow part and hope someone can help me.
I've seen this document https://www.tensorflow.org/api_docs/python/tf/audio/decode_wav and executed tf.audio.decode_wav( contents, desired_channels=-1, desired_samples=-1, name=None )
The only thing I've changed is the contents, changing to my path name.
But still get an error!
Any methods to convert it? And I want to output something like this. .tfrecord-00000-of-00008
Read the .wav file into a string of bytes and then decode it:
import tensorflow as tf
wav_contents = tf.io.read_file("file.wav")
audio, sample_rate = tf.audio.decode_wav(contents=wav_contents)
audio.shape
This example was borrowed from the TensorFlow tutorial on reading audio files.

How to use image jpg with numpy.load()

I try to implement this code, using colab:
x = np.load('data_sample.npy',allow_pickle=True)
stacked_x = np.concatenate([x,x,x],1)
stacked_x.shape
but my sample was an image in jpg format, so I wasn't able to convert these images to .npy to use it.
actually, I tried this code:
import numpy as np
array = np.asarray('image.JPG')
print(array.tobytes())
print(array)
x = np.load(array,allow_pickle=True)
stacked_x = np.concatenate([x,x,x],1)
stacked_x.shape
print(x)
but I got:
and when I use this code :
x = np.load(array.tobytes(),allow_pickle=True)
I got:
so, any suggestion to solve this, precisely to convert .jpg to .npy?
Look at what your code does:
In [57]: np.asarray('image.JPG')
Out[57]: array('image.JPG', dtype='<U9')
In [58]: np.asarray('image.JPG').tobytes()
Out[58]: b'i\x00\x00\x00m\x00\x00\x00a\x00\x00\x00g\x00\x00\x00e\x00\x00\x00.\x00\x00\x00J\x00\x00\x00P\x00\x00\x00G\x00\x00\x00'
That's just playing with the string. It's not doing anything with a file named "image.JPG". You need to use some sort of image processing package to first load the file, converting it from the compressed format to a 3d array.
np.load is used to load a file that was created by np.save('file.npy'). It doesn't make sense to give that array variable as the file name. It won't load a jpg file.
np.load('file.npy',allow_pickle=True)

error: (-215:Assertion failed) !_src.empty() in function 'cvtColor' while using OpenCV 4.2 with swift [duplicate]

I am trying to do a basic colour conversion in python however I can't seem to get past the below error. I have re-installed python, opencv and tried on both python 3.4.3 (latest) and python 2.7 (which is on my Mac).
I installed opencv using python's package manager opencv-python.
Here is the code that fails:
frame = cv2.imread('frames/frame%d.tiff' % count)
frame_HSV= cv2.cvtColor(frame,cv2.COLOR_RGB2HSV)
This is the error message:
cv2.error: OpenCV(3.4.3) /Users/travis/build/skvark/opencv-python/opencv/modules/imgproc/src/color.cpp:181: error: (-215:Assertion failed) !_src.empty() in function 'cvtColor'
This error happened because the image didn't load properly. So you have a problem with the previous line cv2.imread. My suggestion is :
check if the image exists in the path you give
check if the count variable has a valid number
If anyone is experiencing this same problem when reading a frame from a webcam:
Verify if your webcam is being used on another task and close it. This wil solve the problem.
I spent some time with this error when I realized my camera was online in a google hangouts group. Also, Make sure your webcam drivers are up to date
I kept getting this error too:
Traceback (most recent call last):
File "face_detector.py", line 6, in <module>
gray_img=cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
cv2.error: OpenCV(4.1.0) C:\projects\opencv-python\opencv\modules\imgproc\src\color.cpp:182: error: (-215:Assertion failed) !_src.empty() in function 'cv::cvtColor
My cv2.cvtColor(...) was working fine with \photo.jpg but not with \news.jpg. For me, I finally realized that when working on Windows with python, those escape characters will get you every time!! So my "bad" photo was being escaped because of the file name beginning with "n". Python took the \n as an escape character and OpenCV couldn't find the file!
Solution:
Preface file names in Windows python with r"...\...\" as in
cv2.imread(r".\images\news.jpg")
If the path is correct and the name of the image is OK, but you are still getting the error
use:
from skimage import io
img = io.imread(file_path)
instead of:
cv2.imread(file_path)
The function imread loads an image from the specified file and returns
it. If the image cannot be read (because of missing file, improper permissions, unsupported or invalid format), the function returns an empty matrix ( Mat::data==NULL ).
check if the image exists in the path and verify the image extension (.jpg or .png)
Check whether its the jpg, png, bmp file that you are providing and write the extension accordingly.
Another thing which might be causing this is a 'weird' symbol in your file and directory names. All umlaut (äöå) and other (éóâ etc) characters should be removed from the file and folder names. I've had this same issue sometimes because of these characters.
Most probably there is an error in loading the image, try checking directory again.
Print the image to confirm if it actually loaded or not
In my case, the image was incorrectly named. Check if the image exists and try
import numpy as np
import cv2
img = cv2.imread('image.png', 0)
cv2.imshow('image', img)
I've been in same situation as well, and My case was because of the Korean letter in the path...
After I remove Korean letters from the folder name, it works.
OR put
[#-*- coding:utf-8 -*-]
(except [ ] at the edge)
or something like that in the first line to make python understand Korean or your language or etc.
then it will work even if there is some Koreans in the path in my case.
So the things is, it seems like there is something about path or the letter.
People who answered are saying similar things. Hope you guys solve it!
I had the same problem and it turned out that my image names included special characters (e.g. château.jpg), which could not bet handled by cv2.imread. My solution was to make a temporary copy of the file, renaming it e.g. temp.jpg, which could be loaded by cv2.imread without any problems.
Note: I did not check the performance of shutil.copy2 vice versa other options. So probably there is a better/faster solution to make a temporary copy.
import shutil, sys, os, dlib, glob, cv2
for f in glob.glob(os.path.join(myfolder_path, "*.jpg")):
shutil.copy2(f, myfolder_path + 'temp.jpg')
img = cv2.imread(myfolder_path + 'temp.jpg')
img = cv2.cvtColor(img, cv2.COLOR_BGR2RGB)
os.remove(myfolder_path + 'temp.jpg')
If there are only few files with special characters, renaming can also be done as an exeption, e.g.
for f in glob.glob(os.path.join(myfolder_path, "*.jpg")):
try:
img = cv2.imread(f)
img = cv2.cvtColor(img, cv2.COLOR_BGR2RGB)
except:
shutil.copy2(f, myfolder_path + 'temp.jpg')
img = cv2.imread(myfolder_path + 'temp.jpg')
img = cv2.cvtColor(img, cv2.COLOR_BGR2RGB)
os.remove(myfolder_path + 'temp.jpg')
In my case it was a permission issue. I had to:
chmod a+wrx the image,
then it worked.
must please see guys that the error is in the cv2.imread() .Give the right path of the image. and firstly, see if your system loads the image or not. this can be checked first by simple load of image using cv2.imread().
after that ,see this code for the face detection
import numpy as np
import cv2
cascPath = "/Users/mayurgupta/opt/anaconda3/lib/python3.7/site- packages/cv2/data/haarcascade_frontalface_default.xml"
eyePath = "/Users/mayurgupta/opt/anaconda3/lib/python3.7/site-packages/cv2/data/haarcascade_eye.xml"
smilePath = "/Users/mayurgupta/opt/anaconda3/lib/python3.7/site-packages/cv2/data/haarcascade_smile.xml"
face_cascade = cv2.CascadeClassifier(cascPath)
eye_cascade = cv2.CascadeClassifier(eyePath)
smile_cascade = cv2.CascadeClassifier(smilePath)
img = cv2.imread('WhatsApp Image 2020-04-04 at 8.43.18 PM.jpeg')
gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
faces = face_cascade.detectMultiScale(gray, 1.3, 5)
for (x,y,w,h) in faces:
img = cv2.rectangle(img,(x,y),(x+w,y+h),(255,0,0),2)
roi_gray = gray[y:y+h, x:x+w]
roi_color = img[y:y+h, x:x+w]
eyes = eye_cascade.detectMultiScale(roi_gray)
for (ex,ey,ew,eh) in eyes:
cv2.rectangle(roi_color,(ex,ey),(ex+ew,ey+eh),(0,255,0),2)
cv2.imshow('img',img)
cv2.waitKey(0)
cv2.destroyAllWindows()
Here, cascPath ,eyePath ,smilePath should have the right actual path that's picked up from lib/python3.7/site-packages/cv2/data here this path should be to picked up the haarcascade files
Your code can't find the figure or the name of your figure named the by error message.
Solution:
import cv2
import numpy as np
import matplotlib.pyplot as plt
img=cv2.imread('哈哈.jpg')#solution:img=cv2.imread('haha.jpg')
print(img)
If anyone is experiencing this same problem when reading a frame from a webcam [with code similar to "frame = cv2.VideoCapture(0)"] and work in Jupyter Notebook, you may try:
ensure previously tried code is not running already and restart Jupyter Notebook kernel
SEPARATE code "frame = cv2.VideoCapture(0)" in separate cell on place where it is [previous code put in cell above, code under put to cell down]
then run all the code above cell where is "frame = cv2.VideoCapture(0)"
then try run next cell with its only code "frame = cv2.VideoCapture(0)" - AND - till you will continue in executing other cells - ENSURE - that ASTERIX on the left side of this particular cell DISAPEAR and command order number appear instead - only then continue
now you can try execute the rest of your code as your camera input should not be empty anymore :-)
After end, ensure you close all your program and restart kernel to prepare it for another run
As #shaked litbak , this error arised with my initial use with the ASCII-generator , as i naively thought i just had to add to the ./data directory , with its load automatically .
I had to append the --input option with the desired file path .
I checked my image file path and it was correct. I made sure there was no corrupt images.The problem was with my mac. It sometimes have a hidden file called .DS_Store which was saved together with the image file path. Therefore cv2 was having a problem with that file.So I solved the problem by deleting .DS_Store
I also encountered this type of error:
error: OpenCV(4.1.2) /io/opencv/modules/imgproc/src/color.cpp:182: error: (-215:Assertion failed) !_src.empty() in function 'cvtColor'
The solution was to load the image properly. Since the file mentioned was wrong, images were not loaded and hence it threw this error. You can check the path of the image or if uploading an image through colab or drive, make sure that the image is present in the drive.
I encounter the problem when I try to load the image from non-ASCII path.
If I simply use imread to load the image, I am only able to get None.
Here is my solution:
import cv2
import numpy as np
path = r'D:\map\上海地图\abc.png'
image = cv2.imdecode(np.fromfile(path, dtype=np.uint8), cv2.IMREAD_UNCHANGED)
Similar thing will happen when I save the image in a non-ASCII path. It will not be successfully saved without any warnings. And here is what I did.
import cv2
import numpy as np
path = r'D:\map\上海地图\abc.png'
cv2.imencode('.png', image)[1].tofile(path)
path = os.path.join(raw_folder, folder, file)
print('[DEBUG] path:', path)
img = cv2.imread(path) #read path Image
if img is None: # check if the image exists in the path you give
print('Wrong path:', path)
else: # It completes the steps
img = cv2.resize(img, dsize=(128,128))
pixels.append(img)
The solution os to ad './' before the name of image before reading it...
Just Try Degrading the OpenCV
in python Shell (in cmd)
>>> import cv2
>>> cv2.__version__
after Checking in cmd
pip uninstall opencv-python
after uninstalling the version of opencv install
pip install opencv-python==3.4.8.29

Accessing carray of pointcloud using pytables

I am having a hard time understanding how to access the data in a carray.
http://carray.pytables.org/docs/manual/index.html
I have a carray that I can view in a group structure using vitables - but how to open it and retrieve the data it beyond me.
The data are a point cloud that is 3 levels down that I want to make a scatter plot of and extract as a .obj file..
I then have to loop through (many) clouds and do the same thing..
Is there anyone that can give me a simple example of how to do this?
This was my attempt:
import carray as ca
fileName = 'hdf5_example_db.h5'
a = ca.open(rootdir=fileName)
print a
I managed to solve my issue.. I wasn't treating the carray differently to the rest of the hierarchy. I needed to first load the entire db, then refer to the data I needed. I ended up not having to use carray, and just stuck to h5py:
from __future__ import print_function
import h5py
import numpy as np
# read the hdf5 format file
fileName = 'hdf5_example_db.h5'
f = h5py.File(fileName, 'r')
# full path of carry type data (which is in ply format)
dataspace = '/objects/object_000/object_model'
# view the data
print(f[dataspace])
# print to ply file
with open('object_000.ply', 'w') as fo:
for line in f[dataspace]:
fo.write(line+'\n')