I'm working with the trimesh Python library, and I couldn't wrap my head around working with colors from reading the docs (a Spartan API reference) and examples. I'm not even sure if I'm setting the face colors right, if I can modify mesh.visual.face_colors directly or if I should make a ColorVisuals-type object.
But the main question is, can I set the color of different faces of a mesh approximately (I know there can be nasty edge cases) according to it being "overlapping" to faces in the original meshes I had before?
from shapely import Polygon
import trimesh
pts = ((100, 100), (400, 100), (400, 400), (100, 400))
hole = ((150, 150), (350, 150), (350, 350), (150, 350))
p = Polygon(pts, [hole])
mesh = trimesh.creation.extrude_polygon(p, 100)
other = mesh.copy()
other.apply_translation((150, 50, 50))
mesh = mesh.union(other)
# Silly idea (most faces wouldn't be the same) and it doesn't work, I get an error.
# other_v_set = set(other.vertices)
# colors = [([255, 0, 0] if set(mesh.vertices[v] for v in f).issubset(other_v_set)
# else [0, 255, 0]) for f in mesh.faces]
# mesh.visual = trimesh.visual.ColorVisuals(mesh, colors)
mesh.show()
I have the following Python code:
FONT = cv2.FONT_HERSHEY_SIMPLEX
FONT_SCALE = 1.0
FONT_THICKNESS = 2
bg_color = (255, 255, 255)
label_color = (0, 0, 0)
label = 'Propaganda'
label_width, label_height = cv2.getTextSize(label, FONT, FONT_SCALE, FONT_THICKNESS)[0]
label_patch = np.zeros((label_height, label_width, 3), np.uint8)
label_patch[:,:] = bg_color
I create a new blank image, with the size returned by getTextSize, and then, I add the text at the bottom-left point, according to the docs, which is x = 0, y = (height - 1) and with the same font, scale and thickness parameters used for getTextSize
cv2.putText(label_patch, label, (0, label_height - 1), FONT, FONT_SCALE, label_color, FONT_THICKNESS)
But when I use imshow or imwrite on the image label_patch, this is the results I get:
It can easily be seen that lowercase p and lowercase g are cut in the middle, such that g and a cannot even be distinguished. How can I make OpenCV's getTextSize return the correct size, and how can I make OpenCV's putText start drawing the text from the actual lowest point?
Found the solution to my problem, so sharing it here.
It turns out that there is another parameter that getTextSize returns, which is the baseline. It should have been taken into account when creating the box: the box height should be label_height + baseline:
(label_width, label_height), baseline = cv2.getTextSize(label, FONT, FONT_SCALE, FONT_THICKNESS)
label_patch = np.zeros((label_height + baseline, label_width, 3), np.uint8)
label_patch[:,:] = bg_color
Now, adding the text at the same point as before, which means that the baseline pixels will remain below (the point has actually moved one pixel down, as advised by #api55):
cv2.putText(label_patch, label, (0, label_height), FONT, FONT_SCALE, label_color, FONT_THICKNESS)
And the result:
I wan't to change every colors in my image to grey;but I don't wan't to make any changes to my image alpha.I wan't to keep transparent pixels of my image.this is my code:
from pygame import *
init()
screen = display.set_mode([640, 640])
r = image.load('g.png')
r = transform.scale(r,(640,640))
ar = PixelArray (r)
ar.replace ((255, 255, 255), (110, 110, 110), 0.15)
del ar
screen.blit(r, (0,0))
display.update()
Here's a workaround: Paint all transparent pixels of your image-file g.png with a color you're never going to use, like magic-pink or pitch-black. Then just change ever color of the image but you're transparent color - and then, before you blit, convert your array to a surface and set the colorkey to your transparent color, like this: surface.set_colorkey((225, 0, 225))
I am working on an image-generation program, and I have an issue trying to directly edit the pixels of an image.
My original method, which works, was simply:
image = Image.new('RGBA', (width, height), background)
drawing_image = ImageDraw.Draw(image)
# in some loop that determines what to draw and at what color
drawing_image.point((x, y), color)
This works fine, but I thought directly editing pixels might be slightly faster. I plan on using "very" high resolutions (maybe 10000px by 10000px), so even a slight decrease in time per pixel will be a large decrease overall.
I tried using this:
image = Image.new('RGBA', (width, height), background)
pixels = image.load()
# in some loop that determines what to draw and at what color
pixels[x][y] = color # note: color is a hex-formatted string, i.e "#00FF00"
This gives me an error:
Traceback (most recent call last):
File "my_path\my_file.py", line 100, in <module>
main()
File "my_path\my_file.py", line 83, in main
pixels[x][y] = color
TypeError: argument must be sequence of length 2
How does the actual pixels[x][y] work? I seem to be missing a fundamental concept here (I've never worked with directly editing pixels prior to this), or at least just not understanding what arguments are required. I even tried pixels[x][y] = (0, 0, 0), but that raised the same error.
In addition, is there a faster way to edit the pixels? I've heard that using the pixels[x][y] = some_color is faster than drawing to the image, but I'm open to any other faster method.
Thanks in advance!
You need to pass a tuple index as pixels[(x, y)] or simply pixels[x, y], for example:
#-*- coding: utf-8 -*-
#!python
from PIL import Image
width = 4
height = 4
background = (0, 0, 0, 255)
image = Image.new("RGBA", (width, height), background)
pixels = image.load()
pixels[0, 0] = (255, 0, 0, 255)
pixels[0, 3] = (0, 255, 0, 255)
pixels[3, 3] = (0, 0, 255, 255)
pixels[3, 0] = (255, 255, 255, 255)
image.save("image.png")
Using Python I want to be able to draw text at different angles using PIL.
For example, imagine you were drawing the number around the face of a clock. The number 3 would appear as expected whereas 12 would we drawn rotated counter-clockwise 90 degrees.
Therefore, I need to be able to draw many different strings at many different angles.
Draw text into a temporary blank image, rotate that, then paste that onto the original image. You could wrap up the steps in a function. Good luck figuring out the exact coordinates to use - my cold-fogged brain isn't up to it right now.
This demo writes yellow text on a slant over an image:
# Demo to add rotated text to an image using PIL
import Image
import ImageFont, ImageDraw, ImageOps
im=Image.open("stormy100.jpg")
f = ImageFont.load_default()
txt=Image.new('L', (500,50))
d = ImageDraw.Draw(txt)
d.text( (0, 0), "Someplace Near Boulder", font=f, fill=255)
w=txt.rotate(17.5, expand=1)
im.paste( ImageOps.colorize(w, (0,0,0), (255,255,84)), (242,60), w)
It's also usefull to know our text's size in pixels before we create an Image object. I used such code when drawing graphs. Then I got no problems e.g. with alignment of data labels (the image is exactly as big as the text).
(...)
img_main = Image.new("RGB", (200, 200))
font = ImageFont.load_default()
# Text to be rotated...
rotate_text = u'This text should be rotated.'
# Image for text to be rotated
img_txt = Image.new('L', font.getsize(rotate_text))
draw_txt = ImageDraw.Draw(img_txt)
draw_txt.text((0,0), rotate_text, font=font, fill=255)
t = img_value_axis.rotate(90, expand=1)
The rest of joining the two images together is already described on this page.
When you rotate by an "unregular" angle, you have to improve this code a little bit. It actually works for 90, 180, 270...
Here is a working version, inspired by the answer, but it works without opening or saving images.
The two images have colored background and alpha channel different from zero to show what's going on. Changing the two alpha channels from 92 to 0 will make them completely transparent.
from PIL import Image, ImageFont, ImageDraw
text = 'TEST'
font = ImageFont.truetype(r'C:\Windows\Fonts\Arial.ttf', 50)
width, height = font.getsize(text)
image1 = Image.new('RGBA', (200, 150), (0, 128, 0, 92))
draw1 = ImageDraw.Draw(image1)
draw1.text((0, 0), text=text, font=font, fill=(255, 128, 0))
image2 = Image.new('RGBA', (width, height), (0, 0, 128, 92))
draw2 = ImageDraw.Draw(image2)
draw2.text((0, 0), text=text, font=font, fill=(0, 255, 128))
image2 = image2.rotate(30, expand=1)
px, py = 10, 10
sx, sy = image2.size
image1.paste(image2, (px, py, px + sx, py + sy), image2)
image1.show()
The previous answers draw into a new image, rotate it, and draw it back into the source image. This leaves text artifacts. We don't want that.
Here is a version that instead crops the area of the source image that will be drawn onto, rotates it, draws into that, and rotates it back. This means that we draw onto the final surface immediately, without having to resort to masks.
def draw_text_90_into (text: str, into, at):
# Measure the text area
font = ImageFont.truetype (r'C:\Windows\Fonts\Arial.ttf', 16)
wi, hi = font.getsize (text)
# Copy the relevant area from the source image
img = into.crop ((at[0], at[1], at[0] + hi, at[1] + wi))
# Rotate it backwards
img = img.rotate (270, expand = 1)
# Print into the rotated area
d = ImageDraw.Draw (img)
d.text ((0, 0), text, font = font, fill = (0, 0, 0))
# Rotate it forward again
img = img.rotate (90, expand = 1)
# Insert it back into the source image
# Note that we don't need a mask
into.paste (img, at)
Supporting other angles, colors etc is trivial to add.
Here's a fuller example of watermarking diagonally. Handles arbitrary image ratios, sizes and text lengths by calculating the angle of the diagonal and font size.
from PIL import Image, ImageFont, ImageDraw
import math
# sample dimensions
pdf_width = 1000
pdf_height = 1500
#text_to_be_rotated = 'Harry Moreno'
text_to_be_rotated = 'Harry Moreno (morenoh149#gmail.com)'
message_length = len(text_to_be_rotated)
# load font (tweak ratio based on your particular font)
FONT_RATIO = 1.5
DIAGONAL_PERCENTAGE = .5
diagonal_length = int(math.sqrt((pdf_width**2) + (pdf_height**2)))
diagonal_to_use = diagonal_length * DIAGONAL_PERCENTAGE
font_size = int(diagonal_to_use / (message_length / FONT_RATIO))
font = ImageFont.truetype(r'./venv/lib/python3.7/site-packages/reportlab/fonts/Vera.ttf', font_size)
#font = ImageFont.load_default() # fallback
# target
image = Image.new('RGBA', (pdf_width, pdf_height), (0, 128, 0, 92))
# watermark
opacity = int(256 * .5)
mark_width, mark_height = font.getsize(text_to_be_rotated)
watermark = Image.new('RGBA', (mark_width, mark_height), (0, 0, 0, 0))
draw = ImageDraw.Draw(watermark)
draw.text((0, 0), text=text_to_be_rotated, font=font, fill=(0, 0, 0, opacity))
angle = math.degrees(math.atan(pdf_height/pdf_width))
watermark = watermark.rotate(angle, expand=1)
# merge
wx, wy = watermark.size
px = int((pdf_width - wx)/2)
py = int((pdf_height - wy)/2)
image.paste(watermark, (px, py, px + wx, py + wy), watermark)
image.show()
Here it is in a colab https://colab.research.google.com/drive/1ERl7PiX6xKy5H9EEMulBKPgglF6euCNA?usp=sharing you should provide an example image to the colab.
I'm not saying this is going to be easy, or that this solution will necessarily be perfect for you, but look at the documentation here:
http://effbot.org/imagingbook/pil-index.htm
and especially pay attention to the Image, ImageDraw, and ImageFont modules.
Here's an example to help you out:
import Image
im = Image.new("RGB", (100, 100))
import ImageDraw
draw = ImageDraw.Draw(im)
draw.text((50, 50), "hey")
im.rotate(45).show()
To do what you really want you may need to make a bunch of separate correctly rotated text images and then compose them all together with some more fancy manipulation. And after all that it still may not look great. I'm not sure how antialiasing and such is handled for instance, but it might not be good. Good luck, and if anyone has an easier way, I'd be interested to know as well.
If you a using aggdraw, you can use settransform() to rotate the text. It's a bit undocumented, since effbot.org is offline.
# Matrix operations
def translate(x, y):
return np.array([[1, 0, x], [0, 1, y], [0, 0, 1]])
def rotate(angle):
c, s = np.cos(angle), np.sin(angle)
return np.array([[c, -s, 0], [s, c, 0], [0, 0, 1]])
def draw_text(image, text, font, x, y, angle):
"""Draw text at x,y and rotated angle radians on the given PIL image"""
m = np.matmul(translate(x, y), rotate(angle))
transform = [m[0][0], m[0][1], m[0][2], m[1][0], m[1][1], m[1][2]]
draw = aggdraw.Draw(image)
draw.settransform(transform)
draw.text((tx, ty), text, font)
draw.settransform()
draw.flush()