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`plotly.express.imshow` blurry when exported to pdf

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#4,846 3 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
52/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Active
Tech stack
plotly, python

Research direction

Start by reproducing the issue with the provided NumPy and plotly.express.imshow example, using fig.write_image('test.pdf', format='pdf') and the reported plotly and kaleido versions. Compare the exported image content with the axes and legends; done means the image is rendered sharply in the PDF without degrading the other elements.

Written by the indexing model from the issue text.

Description

bug P2

When writing plotly.express.imshow figure to pdf using write_image, the contents are rendered extremely blurry while axes and legends are rendered just fine: test.pdf

Code to produce figure:

import numpy as np
import plotly.express as px

np.random.seed(0)
data = np.random.randint(low=0, high=2, size=(10, 10))

fig = px.imshow(data)
fig.write_image('test.pdf', format='pdf')

I am using plotly version 5.24.1 and kaleido version 0.2.1.

Dominant language
Python
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Forks
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Avg merge
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Merged PRs (30d)
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