Develop Reference

Convert mp3 song image from png to jpg

I have a set of many songs, some of which have png images in metadata, and I need to convert these to jpg.
I know how to convert png images to jpg in general, but I am currently accessing metadata using eyed3, which returns ImageFrame objects, and I don't know how to manipulate these. I can, for instance, access the image type with
print(img.mime_type)
which returns
image/png
but I don't know how to progress from here. Very naively I tried loading the image with OpenCV, but it is either not a compatible format or I didn't do it properly. And anyway I wouldn't know how to update the old image with the new one either!
Note: While I am currently working with eyed3, it is perfectly fine if I can solve this any other way.

I was finally able to solve this, although in a not very elegant way.
The first step is to load the image. For some reason I could not make this work with eyed3, but TinyTag does the job:
from PIL import Image
from tinytag import TinyTag
tag = TinyTag.get(mp3_path, image=True)
image_data = tag.get_image()
img_bites = io.BytesIO(image_data)
photo = Image.open(im)
Then I manipulate it. For example we may resize it and save it as jpg. Because we are using Pillow (PIL) for these operations, we actually need to save the image and finally load it back to get the binary data (this detail is probably what should be improved in the process).
photo = photo.resize((500, 500)) # suppose we want 500 x 500 pixels
rgb_photo = photo.convert("RGB")
rgb_photo.save(temp_file_path, format="JPEG")
The last step is thus to load the image and set it as metadata. You have more details about this step in this answer.:
audio_file = eyed3.load(mp3_path) # this has been loaded before
audio_file.tag.images.set(
3, open(temp_file_path, "rb").read(), "image/jpeg"
)
audio_file.tag.save()

python3.5 PIL Image not displaying image

The following code does not display the image lists.jpg (in current dir):
print(dir(Image)) displays components; im.size, im.filename, im.format all return correct values.
What have I not done to display this jpg file?
from PIL import Image
im = Image.open("lists.jpg")
im.show() # did not work - perhaps due to the environment Jupyter Notebooks
Solution: replaced module with another with immediate results.
from IPython.display import Image
Image(filename='lists.jpg')

I know it is quite late to post but I will do it for new readers.
This problem arises in case of Jupyter Notebooks. Using show() does not display the image. So discard calling show() like in the code below. This will display the image in the output of the cell.
from PIL import Image
im = Image.open("lists.jpg")
im

To display the image on screen:
from PIL import Image
im = Image.open("lists.jpg")
im.show()
See also http://pillow.readthedocs.io/en/4.0.x/reference/Image.html

OpenCV Python not opening images with imread()

I'm not entirely sure why this is happening but I am in the process of making a program and I am having tons of issues trying to get opencv to open images using imread. I keep getting errors saying that the image is 0px wide by 0px high. This isn't making much sense to me so I searched around on here and I'm not getting any answers from SO either.
I have taken about 20 pictures and they are all using the same device. Probably 8 of them actually open and work correctly, the rest don't. They aren't corrupted either because they open in other programs. I have triple checked the paths and they are using full paths.
Is anyone else having issues like this? All of my files are .jpgs and I am not seeing any problems on my end. Is this a bug or am I doing something wrong?
Here is a snippet of the code that I am using that is reproducing the error on my end.
imgloc = "F:\Kyle\Desktop\Coinjar\Test images\ten.png"
img = cv2.imread(imgloc)
cv2.imshow('img',img)
When I change the file I just adjust the name of the file itself the entire path doesn't change it just refuses to accept some of my images which are essentially the same ones.
I am getting this error from a later part of the code where I try to use img.shape
Traceback (most recent call last):
File "F:\Kyle\Desktop\Coinjar\CoinJar Test2.py", line 14, in <module>
height, width, depth = img.shape
AttributeError: 'NoneType' object has no attribute 'shape'
and I am getting this error when I try to show a window from the code snippet above.
Traceback (most recent call last):
File "F:\Kyle\Desktop\Coinjar\CoinJar Test2.py", line 11, in <module>
cv2.imshow('img',img)
error: ..\..\..\..\opencv\modules\highgui\src\window.cpp:261: error: (-215) size.width>0 && size.height>0 in function cv::imshow

Probably you have problem with special meaning of \ in text - like \t or \n
Use \\ in place of \
imgloc = "F:\\Kyle\\Desktop\\Coinjar\\Test images\\ten.png"
or use prefix r'' (and it will treat it as raw text without special codes)
imgloc = r"F:\Kyle\Desktop\Coinjar\Test images\ten.png"
EDIT:
Some modules accept even / like in Linux path
imgloc = "F:/Kyle/Desktop/Coinjar/Test images/ten.png"

From my experience, file paths that are too long (OS dependent) can also cause cv2.imread() to fail.
Also, when it does fail, it often fails silently, so it is hard to even realize that it failed, and usually something further the the code will be what sparks the error.
Hope this helps.

Faced the same problem on Windows: cv.imread returned None when reading jpg files from a subfolder. The same code and folder structure worked on Linux.
Found out that cv.imread processes the same jpg files, if they are in the same folder as the python file.
My workaround:
copy the image file to the python file folder
use this file in cv.imread
remove redundant image file
import os
import shutil
import cv2 as cv
image_dir = os.path.join('path', 'to', 'image')
image_filename = 'image.jpg'
full_image_path = os.path.join(image_dir, image_filename)
image = cv.imread(full_image_path)
if image is None:
shutil.copy(full_image_path, image_filename)
image = cv.imread(image_filename)
os.remove(image_filename)
...

I had i lot of trouble with cv.imread() not finding my Image. I think i tryed everything involving changing the path. The os.path.exists(file_path) function also gave me back a True.
I finaly solved the problem by loading the images with imageio.
img = imageio.imread('file_path')
This also loads the img in a numpy array and you can use funktions like cv.matchTemplate() on this object. But i would recomment if u are doing stuff with multiple images that you then read all of them with imageio because i found diffrences in the arrays produced by .imread() from the two libs (opencv, imageio) on a File both of them could open.
I hope i could help someone

Take care to :
try imread() with a reliable picture,
and the correct path in your context like (see Kyle772 answer). For me either //or \.
I lost a couple of hours trying with 2 images saved from a left click in a browser. As soon as I took a personal camera image, it works fine.
Spyder screen shot
#context windows10 / anaconda / python 3.2.0
import cv2
print(cv2.__version__) # 3.2.0
imgloc = "D:/violettes/Software/Central/test.jpg" #this path works fine.
# imgloc = "D:\\violettes\\Software\\Central\\test.jpg" this path works fine also.
#imgloc = "D:\violettes\Software\Central\test.jpg" #this path fails.
img = cv2.imread(imgloc)
height, width, channels = img.shape
print (height, width, channels)
python opencv image-loading imread

I know that the question is already answered but in case anybody still is not able to load images with imread. It may be because there are letters in the string path witch imread does not accept.
For exmaple umlauts and diacritical marks.

My suggestion for everyone facing the same problem is to try this:
cv2.imshow("image", img)
The img is keyword. Never forget.

When you get error like this AttributeError: 'NoneType' object has no attribute 'shape'
Try with new_image=image.copy

Split .TIF file using PIL

I took a look at the Split multi-page tiff with python file for Splitting a .TIFF File, however to be honest, I didn't fully understand the answers, and I'm hoping for a little clarification.
I am attempting to take a .Tif file with multiple Invoices in it and Split it into each page which will then be Zipped Up and uploaded into a database. PIL is installed on the computers that will be running this program, as such I'd like to stick with the PIL Library. I know that I can view information such as the Size of each Image using PIL after it's open, however when I attempt to Save each it gets dicey. (Example Code Below)
def Split_Images(img,numFiles):
ImageFile = Image.open(img)
print ImageFile.size[0]
print ImageFile.size[1]
ImageFile.save('InvoiceTest1.tif')[0]
ImageFile.save('InvoiceTest2.tif')[1]
However when I run this code I get the following Error:
TypeError: 'NoneType' object has no attribute '__getitem__'
Any Suggestions?
Thank you in advance,

You need the PIL Image "seek" method to access the different pages.
from PIL import Image
img = Image.open('multipage.tif')
for i in range(4):
try:
img.seek(i)
img.save('page_%s.tif'%(i,))
except EOFError:
break

Resize image in Python without losing EXIF data

I need to resize jpg images with Python without losing the original image's EXIF data (metadata about date taken, camera model etc.). All google searches about python and images point to the PIL library which I'm currently using, but doesn't seem to be able to retain the metadata. The code I have so far (using PIL) is this:
img = Image.open('foo.jpg')
width,height = 800,600
if img.size[0] < img.size[1]:
width,height = height,width
resized_img = img.resize((width, height), Image.ANTIALIAS) # best down-sizing filter
resized_img.save('foo-resized.jpg')
Any ideas? Or other libraries that I could be using?

There is actually a really simple way of copying EXIF data from a picture to another with only PIL. Though it doesn't permit to modify the exif tags.
image = Image.open('test.jpg')
exif = image.info['exif']
# Your picture process here
image = image.rotate(90)
image.save('test_rotated.jpg', 'JPEG', exif=exif)
As you can see, the save function can take the exif argument which permits to copy the raw exif data in the new image when saving. You don't actually need any other lib if that's all you want to do. I can't seem to find any documentation on the save options and I don't even know if that's specific to Pillow or working with PIL too. (If someone has some kind of link, I would enjoy if they posted it in the comments)

import jpeg
jpeg.setExif(jpeg.getExif('foo.jpg'), 'foo-resized.jpg')
http://www.emilas.com/jpeg/

You can use pyexiv2 to copy EXIF data from source image. In the following example image is resized using PIL library, EXIF data copied with pyexiv2 and image size EXIF fields are set with new size.
def resize_image(source_path, dest_path, size):
# resize image
image = Image.open(source_path)
image.thumbnail(size, Image.ANTIALIAS)
image.save(dest_path, "JPEG")
# copy EXIF data
source_image = pyexiv2.Image(source_path)
source_image.readMetadata()
dest_image = pyexiv2.Image(dest_path)
dest_image.readMetadata()
source_image.copyMetadataTo(dest_image)
# set EXIF image size info to resized size
dest_image["Exif.Photo.PixelXDimension"] = image.size[0]
dest_image["Exif.Photo.PixelYDimension"] = image.size[1]
dest_image.writeMetadata()
# resizing local file
resize_image("41965749.jpg", "resized.jpg", (600,400))

Why not using ImageMagick?
It is quite a standard tool (for instance, it is the standard tool used by Gallery 2); I have never used it, however it has a python interface as well (or, you can also simply spawn the command) and most of all, should maintain EXIF information between all transformation.

Here's an updated answer as of 2018. piexif is a pure python library that for me installed easily via pip (pip install piexif) and worked beautifully (thank you, maintainers!). https://pypi.org/project/piexif/
The usage is very simple, a single line will replicate the accepted answer and copy all EXIF tags from the original image to the resized image:
import piexif
piexif.transplant("foo.jpg", "foo-resized.jpg")
I haven't tried yet, but it looks like you could also perform modifcations easily by using the load, dump, and insert functions as described in the linked documentation.

For pyexiv2 v0.3.2, the API documentation refers to the copy method to carry over EXIF data from one image to another. In this case it would be the EXIF data of the original image over to the resized image.
Going off #Maksym Kozlenko, the updated code for copying EXIF data is:
source_image = pyexiv2.ImageMetadata(source_path)
source_image.read()
dest_image = pyexiv2.ImageMetadata(dest_path)
dest_image.read()
source_image.copy(dest_image,exif=True)
dest_image.write()

You can use pyexiv2 to modify the file after saving it.

from PIL import Image
img_path = "/tmp/img.jpg"
img = Image.open(img_path)
exif = img.info['exif']
img.save("output_"+img_path, exif=exif)
Tested in Pillow 2.5.3

It seems #Depado's solution does not work for me, in my scenario the image does not even contain an exif segment.
pyexiv2 is hard to install on my Mac, instead I use the module pexif https://github.com/bennoleslie/pexif/blob/master/pexif.py. To "add exif segment" to an image does not contain exif info, I added the exif info contained in an image which owns a exif segment
from pexif import JpegFile
#get exif segment from an image
jpeg = JpegFile.fromFile(path_with_exif)
jpeg_exif = jpeg.get_exif()
#import the exif segment above to the image file which does not contain exif segment
jpeg = JpegFile.fromFile(path_without_exif)
exif = jpeg.import_exif(jpeg_exif)
jpeg.writeFile(path_without_exif)

Updated version of Maksym Kozlenko
Python3 and py3exiv2 v0.7
# Resize image and update Exif data
from PIL import Image
import pyexiv2
def resize_image(source_path, dest_path, size):
# resize image
image = Image.open(source_path)
# Using thumbnail, then 'size' is MAX width or weight
# so will retain aspect ratio
image.thumbnail(size, Image.ANTIALIAS)
image.save(dest_path, "JPEG")
# copy EXIF data
source_exif = pyexiv2.ImageMetadata(source_path)
source_exif.read()
dest_exif = pyexiv2.ImageMetadata(dest_path)
dest_exif.read()
source_exif.copy(dest_exif,exif=True)
# set EXIF image size info to resized size
dest_exif["Exif.Photo.PixelXDimension"] = image.size[0]
dest_exif["Exif.Photo.PixelYDimension"] = image.size[1]
dest_exif.write()

PIL handles EXIF data, doesn't it? Look in PIL.ExifTags.