GIMP Python Plugin to load 2 images as layers - python

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.

Related

Pixels retrieved from Viewer Node within Blender are darker than the actually rendered image... Why?

I am trying to create a pipeline in which I first render an image using the blender python API (I am using Blender 2.90) and then perform some image processing in python. I want to fetch the image directly from blender without first writing the rendered image to disk and then loading it again. I ran the following code within the blender GUI to do so:
import bpy
import numpy as np
import PIL.Image as Image
from skimage.util import img_as_ubyte
resolution_x = 512
resolution_y = 512
# render settings
scene = bpy.context.scene
scene.render.engine = 'BLENDER_EEVEE'
scene.render.resolution_x = resolution_x
scene.render.resolution_y = resolution_y
scene.render.image_settings.file_format = 'PNG'
scene.render.filepath = "path/to/good_image.png"
# create Viewer Layer in Compositor
scene.use_nodes = True
tree = scene.node_tree
nodes = tree.nodes
links = tree.links
for node in nodes:
nodes.remove(node)
render_layer_node = nodes.new('CompositorNodeRLayers')
viewer_node = nodes.new('CompositorNodeViewer')
links.new(viewer_node.inputs[0], render_layer_node.outputs[0])
# render scene and get pixels from Viewer Node
bpy.ops.render.render(write_still=True)
pixels = bpy.data.images['Viewer Node'].pixels
# do some processing and save
img = np.flip(img_as_ubyte(np.array(pixels[:]).reshape((resolution_y, resolution_x, 4))), axis=0)
Image.fromarray(img).save("path/to/bad_image.png")
Problem: The image I get from the Viewer Node is much darker (bad image) than the image saved in the conventional way (good image). Does anyone have an idea why this happens and how to fix it? Does blender maybe treat pixel values differently than I expect?
Some additional information:
Before conversion to uint8, the values of the alpha channel within the dark image are 1.0 (as they actually should be). Background values in the dark image are not 0.0 or negative (as one might guess from appearance), but 0.05...
What I tried:
I thought that pixels might be scaled within range -1 to 1, so I rescaled the pixels to range 0 to 1 before transforming to uint8... Did not lead to the correct image either :(
It's because the image that you get from the Viewer Node is the one "straight from compositing" before color management takes place. You can have a look at the documentation here: this image is still in the linear space.
Your good_image.png on the other hand is obtained after transformation into the "Display Space" (see diagram in the doc). Hence it was transformed into a log-space, maybe gamma-corrected, etc.
Finally, you can get an image that is close to (but slightly different though) to the good image from the viewer node by calling bpy.data.images['Viewer Node'].save_render(filepath) instead, but there is no way to directly extract the color-managed version without rendering to a file first. You can probably do it yourself by adding PyOpenColorIO to your script and applying the color management from this module.

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()

From Raw binary image data to PNG in Python

After searching for a few hours, I ended up on this link. A little background information follows.
I'm capturing live frames of a running embedded device via a hardware debugger. The captured frames are stored as raw binary files, without headers or format. After looking at the above link and understanding, albeit perfunctorily, the NumPY and Matplotlib, I was able to convert the raw binary data to an image successfully. This is important because I'm not sure if the link to the raw binary file will help any one.
I use this code:
import matplotlib.pyplot as plt # study documentation
import numpy as np # " "
iFile = "FramebufferL0_0.bin" # Layer-A
shape = (430, 430) # length and width of the image
dtype = np.dtype('<u2') # unsigned 16 bit little-endian.
oFile = "FramebufferL0_0.png"
fid = open(iFile, 'rb')
data = np.fromfile(fid, dtype)
image = data.reshape(shape)
plt.imshow(image, cmap = "gray")
plt.savefig(oFile)
plt.show()
Now, the image I'm showing is black and white because the color map is gray-scale (right?). The actual captured frame is NOT black and white. That is, the image I see on my embedded device is "colorful".
My question is, how can I calculate actual color of each pixel from the raw binary file? Is there a way I can get the actual color map of the image from the raw binary? I looked into this example and I'm sure that, if I'm able to calculate the R, G and B channels (and Alpha too), I'll be able to recreate the exact image. An example code would be of much help.
An RGBA image has 4 channels, one for each color and one for the alpha value. The binary file seems to have a single channel, as you don't report an error when performing the data.reshape(shape) operation (the shape for the corresponding RGBA image would be (430, 430, 4)).
I see two potential reasons:
The image actual does have colour information but when you are grabbing the data you are only grabbing one of the four channels.
The image is actually a gray-scale image, but the embedded device shows a pseudocolor image, creating the illusion of colour information. Without knowing what the colourmap is being used, it is hard to help you, other than point you towards matplotlib.pyplot.colormaps(), which lists all already available colour maps in matplotlib.
Could you
a) explain the exact source / type of imaging modality, and
b) show a photo of the output of the embedded device?
PS: Also, at least in my hands, the pasted binary file seems to have a size of 122629, which is incongruent with an image shape of (430,430).

Overlaying coloured pixels on top of an image using Python Imaging Library

Okay, first thing first. This is a near duplicate of this question.
However, the issue I am facing is slightly different in a critical way.
In my application, I read a generic file name in, load said image, and display it. Where it gets tricky is I have overlay the appearance of being 'highlighted'. To do this, I was using the Image.blend() function, and blending it with a straight yellow image.
However, when dealing with blend, I was fighting the error that the two images are not compatible to be blended. To solve this, I opened the sample image I had in paint, and just pasted yellow over the whole thing, and saved it as a copy.
It just occurred to me that this will fail when a different type of image is read in by file name. Remember this needs to be generic.
So my question is: Instead of making a copy of the image manually, can I get python to generate one by copying the image and modifying it so it is solid yellow? Note: I do not need to save it after, so just making it happen is enough.
Unfortunately, I am not allowed to share my code, but hopefully the following will give an idea of what I need:
from PIL import Image
desiredWidth = 800
desiredHeight = 600
primaryImage = Image.open("first.jpg").resize((desiredWidth, desiredHeight), Image.ANTIALIAS)
# This is the thing I need fixed:
highlightImage = Image.open("highlight.jpg").resize((desiredWidth, desiredHeight), Image.ANTIALIAS)
toDisplay = Image.blend(primaryImage, highlightImage, 0.3)
Thanks to anyone who can help.
Sounds like you want to make a new image:
fill_color = (255,255,0) #define the colour as (R,G,B) tuple
highlightImage = Image.new(primaryImage.mode, #same mode as the primary
primaryImage.size, #same size as the primary
fill_color)#and the colour defined above
this creates a new image with the same mode and size as the already opened image, but with a solid colour. Cheers.
Also if you are using Pillow instead of original PIL you can even get the color by name:
from PIL.ImageColor import getcolor
overlay = 'yellow'
fill_color = getcolor(overlay, primaryImage.mode)

Using PIL to fill empty image space with nearby colors (aka inpainting)

I create an image with PIL:
I need to fill in the empty space (depicted as black). I could easily fill it with a static color, but what I'd like to do is fill the pixels in with nearby colors. For example, the first pixel after the border might be a Gaussian blur of the filled-in pixels. Or perhaps a push-pull type algorithm described in The Lumigraph, Gortler, et al..
I need something that is not too slow because I have to run this on many images. I have access to other libraries, like numpy, and you can assume that I know the borders or a mask of the outside region or inside region. Any suggestions on how to approach this?
UPDATE:
As suggested by belisarius, opencv's inpaint method is perfect for this. Here's some python code that uses opencv to achieve what I wanted:
import Image, ImageDraw, cv
im = Image.open("u7XVL.png")
pix = im.load()
#create a mask of the background colors
# this is slow, but easy for example purposes
mask = Image.new('L', im.size)
maskdraw = ImageDraw.Draw(mask)
for x in range(im.size[0]):
for y in range(im.size[1]):
if pix[(x,y)] == (0,0,0):
maskdraw.point((x,y), 255)
#convert image and mask to opencv format
cv_im = cv.CreateImageHeader(im.size, cv.IPL_DEPTH_8U, 3)
cv.SetData(cv_im, im.tostring())
cv_mask = cv.CreateImageHeader(mask.size, cv.IPL_DEPTH_8U, 1)
cv.SetData(cv_mask, mask.tostring())
#do the inpainting
cv_painted_im = cv.CloneImage(cv_im)
cv.Inpaint(cv_im, cv_mask, cv_painted_im, 3, cv.CV_INPAINT_NS)
#convert back to PIL
painted_im = Image.fromstring("RGB", cv.GetSize(cv_painted_im), cv_painted_im.tostring())
painted_im.show()
And the resulting image:
A method with nice results is the Navier-Stokes Image Restoration. I know OpenCV has it, don't know about PIL.
Your example:
I did it with Mathematica.
Edit
As per your reuquest, the code is:
i = Import["http://i.stack.imgur.com/uEPqc.png"];
Inpaint[i, ColorNegate#Binarize#i, Method -> "NavierStokes"]
The ColorNegate# ... part creates the replacement mask.
The filling is done with just the Inpaint[] command.
Depending on how you're deploying this application, another option might be to use the Gimp's python interface to do the image manipulation.
The doc page I linked to is oriented more towards writing GIMP plugins in python, rather than interacting with a background gimp instance from a python app, but I'm pretty sure that's also possible (it's been a while since I played with the gimp/python interface, I'm a little hazy).
You can also create the mask with the function CreateImage(), for instance:
inpaint_mask = cv.CreateImage(cv.GetSize(im), 8, 1)

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