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Programming a picture maker template in Python possible?

I'm looking for a library that enables to "create pictures" (or even videos) with the following functions:
Accepting picture inputs
Resizing said inputs to fit given template / scheme
Positioning the pictures in pre-set up layers or coordinates
A rather schematic approach to look at this:
whereas the red spots are supposed to represent e.g. text, picture (or if possible video) elements.
The end goal would be to give the .py script multiple input pictures and the .py creating a finished version like mentioned above.
Solutions I tried were looking into Python PIL, but I wasn't able to find what I was looking for.

Yes, it is possible to do this with Python.
The library you are looking for is OpenCV([https://opencv.org][1]/).
Some basic OpenCV python tutorials (https://docs.opencv.org/master/d9/df8/tutorial_root.html).
1) You can use imread() function to read images from files.
2) You can use resize() function to resize the images.
3) You can create a empty master numpy array matching the size and depth(color depth) of the black rectangle in the figure you have shown, resize your image and copy the contents into the empty array starting from the position you want.
Below is a sample code which does something close to what you might need, you can modify this to suit your actual needs. (Since your requirements are not clear I have written the code like this so that it can at least guide you.)
import numpy as np
import cv2
import matplotlib.pyplot as plt
# You can store most of these values in another file and load them.
# You can modify this to set the dimensions of the background image.
BG_IMAGE_WIDTH = 100
BG_IMAGE_HEIGHT = 100
BG_IMAGE_COLOR_DEPTH = 3
# This will act as the black bounding box you have shown in your figure.
# You can also load another image instead of creating empty background image.
empty_background_image = np.zeros(
(BG_IMAGE_HEIGHT, BG_IMAGE_WIDTH, BG_IMAGE_COLOR_DEPTH),
dtype=np.int
)
# Loading an image.
# This will be copied later into one of those red boxes you have shown.
IMAGE_PATH = "./image1.jpg"
foreground_image = cv2.imread(IMAGE_PATH)
# Setting the resize target and top left position with respect to bg image.
X_POS = 4
Y_POS = 10
RESIZE_TARGET_WIDTH = 30
RESIZE_TARGET_HEIGHT = 30
# Resizing
foreground_image= cv2.resize(
src=foreground_image,
dsize=(RESIZE_TARGET_WIDTH, RESIZE_TARGET_HEIGHT),
)
# Copying this into background image
empty_background_image[
Y_POS: Y_POS + RESIZE_TARGET_HEIGHT,
X_POS: X_POS + RESIZE_TARGET_WIDTH
] = foreground_image
plt.imshow(empty_background_image)
plt.show()

GIMP Python Plugin to load 2 images as layers

I'm trying to make a plugin for gimp that opens two images as separate layers and transforms one of them (more on that below). I'm using GIMP 2.10.12.
I've been struggling to find a proper complete documentation for GIMP's Python interface and am mostly just working from what code snippets I've been able to find. This is what I have so far:
#!/usr/bin/env python2
import os
from gimpfu import *
def load_pair(img_f):
mask_f = img_f.replace(IMG_DIR, PRED_DIR)
result_f = os.path.splitext(img_f.replace(IMG_DIR, SAVE_DIR))[0]
result_dir = os.path.dirname(result_f)
if not os.path.isdir(result_dir):
os.makedirs(result_dir)
img = gimp.Image(100, 100)
pdb.gimp_display_new(img)
for f, name, pos in ((img_f, "Image", 0), (mask_f, "Mask", 1)):
layer = pdb.gimp_file_load_layer(img, f)
pdb.gimp_layer_set_name(layer, name)
pdb.gimp_image_insert_layer(img, layer, None, pos)
register(
"python_fu_open_image_pair",
...,
"<Toolbox>/Image/Open Image Pair",
"",
[(PF_FILE, "img_f", "Image:", None)],
[],
load_pair
)
main()
This kind of does what I want but with a couple of problems.
Question 1
Currently I'm using gimp.Image(100, 100) to open a new image. This means I have to then Fit Canvas to Layers and adjust the zoom and position every time I load a new image pair.
Is there a way to find an image's size from pdb before opening it or do I have to use another library (like PIL) for this? I'm trying to keep my plugin's dependencies to a minimum.
The two images are guaranteed to have the same size.
Since File->Open automatically adjusts the canvas to the image size, I would hope there'd be a nice way to achieve this.
Question 2
I would like to automatically create and set the current working file to result_f + '.xcf' (see above code) - such that File -> Save would automatically save to this file. Is this possible in pdb?
Question 3
Most importantly, I currently have the Mask images saved as black-and-white images. Upon loading a mask as a new layer, I'd like to transform the black colour to transparent and white colour to green (0,255,0). Additionally, since they are saved as .jpg images, the white and black aren't necessarily exactly 255 and 0 intensities but can be off by a bit.
How do I do this automatically in my plugin?

The good way would be to load the first image normally, and the rest as additional layers. Otherwise you can reset the canvas size (pdb.gimp_image_resize(...)) once you have loaded all the layers, and then create the Display.
You can give a name and a default file to the image by setting image.name and image.filename.
To convert the white to green use pdb.plug_in_colors_channel_mixer(...) and set all the gains to 0., except green in green. Make the black transparent use pdb.plug_in_colortoalpha(...).
PS: For color2alpha:
import gimpcolor
color=gimpcolor.RGB(0,255,0) # green, integer args: 0->255)
# or
color=gimpcolor.RGB(0.,1.,0) # green, floating point args (0.->1.)
pdb.plug_in_colortoalpha(image, layer, color)
The Python doc is a direct copy of the Scheme one. In Python, the RUN-INTERACTIVE parameter is not positional, so it doesn't appear in most calls, if you need it, it is a keyword parameter.

OpenCV imread transparency gone

I have an image (a captcha) that I download from the web.
When I loaded to opencv it seems to loose its properties or simply mixes the transparent background with the dark/black colors:
Currently the code does nothing but loading a writing again:
captchaImg = cv2.imread('captcha1.png')
cv2.imwrite("captcha2.png", captchaImg)
I have tried loading also with options 0, 1, 2, 3 but the result is the same.

Using the provided constants might help. I do the equivalent of
captchaImg = cv2.imread('captcha1.png', cv2.IMREAD_UNCHANGED)
which reads the alpha channel (if there is one). The REPL says that cv2.IMREAD_UNCHANGED is -1

Well this is a problem with opencv and it has a solution with opencv but it is kind of complex so I went on and use another libary (PIL) that I was going to use any way.
Basically what you do is put a white image behind the transparent one an with that you solve the problem.
The code is the following:
image = Image.open("captcha1.png")
image.convert("RGBA")
canvas = Image.new('RGBA', image.size, (255,255,255,255)) # Empty canvas colour (r,g,b,a)
canvas.paste(image, mask=image) # Paste the image onto the canvas, using it's alpha channel as mask
canvas.save("captcha1.png", format="PNG")
I hope it helps someone with the same problem.

PyGame image save colors distorted

So I have implemented the following screenshot functionality into my game just to log progress and stuff like that. This is my code:
pygame.image.save(screen, save_file)
Pretty basic. I recently upgraded to python 3.3 and have since been having the issue of distorted colors using this function. Here is what I mean:
Distorted Color:
So it looks quite nice, but it isn't how it supposed to be. This is the actual image:
Is this a known issue or is it just me? Are there any fixes to it or is it just a broken function at the moment. I am using pygame 1.9.2pre and I am assuming it is just a bug with the pre release but I was having issues using any other versions of pygame with python 3.3.

Some users have reported difficulty with saving images as pngs:
I only get .tga files even when I specify .png. Very frustrating.
If you use .PNG (uppercase), it will result in an invalid file (at least on my win32). Use .png (lowercase) instead.
PNG does not seem to work, I am able to get a preview of it in Thunar, but everywhere else It says that it is not a valid PNG.
Saving in a different format may be helpful. For example, BMP is a simple format, so it's unlikely that Pygame's implementation will be buggy.
If you really want to save as PNG, you can reverse the distortion by swapping the red channel with the green one. This is fairly easy. For example, using PIL:
from PIL import Image
im = Image.open("screenshot.png")
width, height = im.size
pix = im.load()
for i in range(width):
for j in range(height):
r,g,b = pix[i,j]
pix[i,j] = (g,r,b)
im.save("output.png")
Or you can save as BMP and convert to PNG after the fact:
from PIL import Image
im = Image.open("screenshot.bmp")
im.save("screenshot.png")

for future reference, this trick worked for me:
from PIL import Image
imgdata = pygame.surfarray.array3d(screen).transpose([1,0,2])[:,:,::-1]
Image.fromarray(imgdata).save('output.png')

opencv zoom function strange results

i am trying to write a zoom function which looks something like this:
centre = ((im.width-1)/2, (im.height-1)/2)
width = int(im.width/(2.0*level))
height = int(im.height/(2.0*level))
rect = (centre[0]-width, centre[1]-height, width*2, height*2)
dst = cv.GetSubRect(im, rect)
cv.Resize(dst, im)
when I use exactly what is written above, I get an odd result where the bottom half of the resultant image is distorted and blurry. However when I replace the line cv.Resize(dst, im) with
size = cv.CloneImage(im)
cv.Resize(dst, size)
im = size
it works fine. Why is this? is there something fundamentally wrong with the way i am performing the zoom?

cv.Resize requires source and destination to be separate memory locations.
Now in the first snippet of your code, you are using cv.GetSubRect to generate an object pointing to area of image which you wish to zoom in. Here the new object is NOT pointing to a new memory location. It is pointing to a memory location which is a subset of original object.
Since cv.Resize requires both the memory locations to be different, what you are getting is a result of undefined behavior.
In the second part of your code you are fulfilling this criteria by using cv.CloneImage.
you are first creating a copy of im (i.e. size. however you could have used a blank image aswell) and then you are using cv.Resize to resize dst and write the resulting image in size.
My advice is to go through the function documentation before using them.