I have 2 transparent PNG images of the same size (142,43). I am trying to vertically stack them. This is one of them:
The end result should be like this (142,86):
It also should retain its transparancy.
I've tried the following code:
from PIL import Image
img_list = [Image.open("example.png"), Image.open("example.png")]
bg = Image.open("1x1_transparent.png")
bg = bg.resize(size=(142, 43*2))
img_list[0] = img_list[0].convert('RGBA')
bg.paste(img_list[0], (0, 0), img_list[0])
bg.save('final.png')
Which imports a 1x1 transparent image, resizes it to the final target size, then tries to put the first image on it. This does not work. The saved image 'final.png' shows an empty image.
Any thoughts what I would be doing wrong?
If your output doesn't seem properly sized, it's probably because of this line:
bg.resize(size=(142, 43*2))
resize returns a new version of the image, leaving the original one unmodified. Try assigning the returned value to something so you can do additional operations on it and ultimately save the output.
bg = bg.resize(size=(142, 43*2))
Related
As I am trying to create a gif file, the file has been created successfully but it is pixelating. So if anyone can help me out with how to increase resolution.
.Here is the code:-
import PIL
from PIL import Image
import NumPy as np
image_frames = []
days = np.arange(0, 12)
for i in days:
new_frame = PIL.Image.open(
r"C:\Users\Harsh Kotecha\PycharmProjects\pythonProject1\totalprecipplot" + "//" + str(i) + ".jpg"
)
image_frames.append(new_frame)
image_frames[0].save(
"precipitation.gif",
format="GIF",
append_images=image_frames[1:],
save_all="true",
duration=800,
loop=0,
quality=100,
)
Here is the Gif file:-
Here are the original images:-
image1
image2
iamge3
Updated Answer
Now that you have provided some images I had a go at disabling the dithering:
#!/usr/bin/env python3
from PIL import Image
# User editable values
method = Image.FASTOCTREE
colors = 250
# Load images precip-01.jpg through precip-12.jpg, quantize to common palette
imgs = []
for i in range(1,12):
filename = f'precip-{i:02d}.jpg'
print(f'Loading: {filename}')
try:
im = Image.open(filename)
pImage = im.quantize(colors=colors, method=method, dither=0)
imgs.append(pImage)
except:
print(f'ERROR: Unable to open {filename}')
imgs[0].save(
"precipitation.gif",
format="GIF",
append_images=imgs[1:],
save_all="true",
duration=800,
loop=0
)
Original Answer
Your original images are JPEGs which means they likely have many thousands of colours 2. When you make an animated GIF (or even a static GIF) each frame can only have 256 colours in its palette.
This can create several problems:
each frame gets a new, distinct palette stored with it, thereby increasing the size of the GIF (each palette is 0.75kB)
colours get dithered in an attempt to make the image look as close as possible to the original colours
different colours can get chosen for frames that are nearly identical which means colours flicker between distinct shades on successive frames - can cause "twinkling" like stars
If you want to learn about GIFs, you can learn 3,872 times as much as I will ever know by reading Anthony Thyssen's excellent notes here, here and here.
Your image is suffering from the first problem because it has 12 "per frame" local colour tables as well as a global colour table3. It is also suffering from the second problem - dithering.
To avoid the dithering, you probably want to do some of the following:
load all images and append them all together into a 12x1 monster image, and find the best palette for all the colours. As all your images are very similar, I think that you'll get away with generating a palette just from the first image without needing to montage all 12 - that'll be quicker
now palettize each image, with dithering disabled and using the single common palette
save your animated sequence of the palletised images, pushing in the singe common palette from the first step above
2: You can count the number of colours in an image with ImageMagick, using:
magick YOURIMAGE -format %k info:
3: You can see the colour tables in a GIF with gifsicle using:
gifsicle -I YOURIMAGE.GIF
I am trying to do something very simple: to subtract a bg image from a video for object tracking. I understood images can be simple subtracted from one another as follows img3 = img2 - img1. However, even when I start simple with one image, add a black line to it and store it as img2, img3 will not just show the line. When I run the following code
import cv2
img1 = cv2.imread("img1.png")
img2 = cv2.imread("img2.png")
img3 = img2 - img1
cv2.imwrite("img3.png",img3)
with bellow img1 and img2:
I get the image on the left below, instead of the image on the right:
I want to use this method for background extraction in a video, e.g. where I have a bg image file that shows an emtpy scene and a video that shows the same scene with sometimes objects moving in and out of the screen. I use the following code but similarly get a B/W image instead of just the object visible without the scene..
import cv2
import numpy as np
from PIL import Image
capture = cv2.VideoCapture("video.mov")
while True:
f, frame = capture.read()
frame = cv2.GaussianBlur(frame,(15,15),0)
frame = frame - bg
cv2.imshow("window", frame)
ps: I know about automatic background subtraction but I have very good background files and very clear empty scenes with very obvious objects so thought this should easily work!
Update: I have just found out about the PIL ImageChops difference function that works for getting what I want with two images but seems not possible to use with a video opened with opencv. Also would it be possible to do ImageChops.difference(img1,img2) manually with numpy arrays?
The closest to expected result you can get using this code:
img3 = 255 - cv2.absdiff(img1,img2)
This code will give you this:
Note that using only cv2.absdiff(img1,img2) will give the oposite of this result, because basically this operation tells you what is the difference between 2 images - if on some position there is no difference, the result (int this position) is 0.
To achieve "perfect result" (exactly what you expect) you need to apply some thresholding(or some other kind of filter which will erase left part of image).
I've been having trouble trying to get PIL to nicely downsample images. The goal, in this case, is for my website to automagically downsample->cache the original image file whenever a different size is required, thus removing the pain of maintaining multiple versions of the same image. However, I have not had any luck. I've tried:
image.thumbnail((width, height), Image.ANTIALIAS)
image.save(newSource)
and
image.resize((width, height), Image.ANTIALIAS).save(newSource)
and
ImageOps.fit(image, (width, height), Image.ANTIALIAS, (0, 0)).save(newSource)
and all of them seem to perform a nearest-neighbout downsample, rather than averaging over the pixels as it should Hence it turns images like
http://www.techcreation.sg/media/projects//software/Java%20Games/images/Tanks3D%20Full.png
to
http://www.techcreation.sg/media/temp/0x5780b20fe2fd0ed/Tanks3D.png
which isn't very nice. Has anyone else bumped into this issue?
That image is an indexed-color (palette or P mode) image. There are a very limited number of colors to work with and there's not much chance that a pixel from the resized image will be in the palette, since it will need a lot of in-between colors. So it always uses nearest-neighbor mode when resizing; it's really the only way to keep the same palette.
This behavior is the same as in Adobe Photoshop.
You want to convert to RGB mode first and resize it, then go back to palette mode before saving, if desired. (Actually I would just save it in RGB mode, and then turn PNGCrush loose on the folder of resized images.)
This is over a year old, but in case anyone is still looking:
Here is a sample of code that will see if an image is in a palette mode, and make adjustments
import Image # or from PIL import Image
img = Image.open(sourceFile)
if 'P' in img.mode: # check if image is a palette type
img = img.convert("RGB") # convert it to RGB
img = img.resize((w,h),Image.ANTIALIAS) # resize it
img = img.convert("P",dither=Image.NONE, palette=Image.ADAPTIVE)
#convert back to palette
else:
img = img.resize((w,h),Image.ANTIALIAS) # regular resize
img.save(newSourceFile) # save the image to the new source
#img.save(newSourceFile, quality = 95, dpi=(72,72), optimize = True)
# set quality, dpi , and shrink size
By converting the paletted version to RGB, we can resize it with the anti alias. If you want to reconvert it back, then you have to set dithering to NONE, and use an ADAPTIVE palette. If there options aren't included your result (if reconverted to palette) will be grainy. Also you can use the quality option, in the save function, on some image formats to improve the quality even more.
I have been hitting my head against the wall for a while with this, so maybe someone out there can help.
I'm using PIL to open a PNG with transparent background and some random black scribbles, and trying to put it on top of another PNG (with no transparency), then save it to a third file.
It comes out all black at the end, which is irritating, because I didn't tell it to be black.
I've tested this with multiple proposed fixes from other posts. The image opens in RGBA format, and it's still messed up.
Also, this program is supposed to deal with all sorts of file formats, which is why I'm using PIL. Ironic that the first format I tried is all screwy.
Any help would be appreciated. Here's the code:
from PIL import Image
img = Image.open(basefile)
layer = Image.open(layerfile) # this file is the transparent one
print layer.mode # RGBA
img.paste(layer, (xoff, yoff)) # xoff and yoff are 0 in my tests
img.save(outfile)
I think what you want to use is the paste mask argument.
see the docs, (scroll down to paste)
from PIL import Image
img = Image.open(basefile)
layer = Image.open(layerfile) # this file is the transparent one
print layer.mode # RGBA
img.paste(layer, (xoff, yoff), mask=layer)
# the transparancy layer will be used as the mask
img.save(outfile)
I need to protect my photos by filling them with copyright logos. My OS is Ubuntu 10.10 and Python 2.6. I intend to use PIL.
Supposed I have a copyright logo like this (You can do this in Photoshop easily):
and a picture like this:
I want to use PIL to get copyrighted pictures like the following (Fill the original pic with pattern):
and Final Result by altering the opacity of logos:
Is there any function in PIL that can do this? Any hint?
Thanks a lot!
PIL is certainly capable of this. First you'll want to create an image that contains the repeated text. It should be, oh, maybe twice the size of the image you want to watermark (since you'll need to rotate it and then crop it). You can use Image.new() to create such an image, then ImageDraw.Draw.text() in a loop to repeatedly plaster your text onto it, and the image's rotate() method to rotate it 15 degrees or so. Then crop it to the size of the original image using the crop() method of the image.
To combine it first you'll want to use ImageChops.multiply() to superimpose the watermark onto a copy of the original image (which will have it at 100% opacity) then ImageChops.blend() to blend the watermarked copy with the original image at the desired opacity.
That should give you enough information to get going -- if you run into a roadblock, post code showing what you've got so far, and ask a specific question about what you're having difficulty with.
Just a sampleļ¼
#!/usr/bin/python
# -*- coding: utf-8 -*-
from PIL import Image
def fill_watermark():
im = Image.open('a.jpg').convert('RGBA')
bg = Image.new(mode='RGBA', size=im.size, color=(255, 255, 255, 0))
logo = Image.open('logo.png') # .rotate(45) if you want, bg transparent
bw, bh = im.size
iw, ih = logo.size
for j in range(bh // ih):
for i in range(bw // iw):
bg.paste(logo, (i * iw, j * ih))
im.alpha_composite(bg)
im.show()
fill_watermark()