Process and analyze tissue images from spatial transcriptomics data using Squidpy. Extract image features, segment cells/nuclei, and compute morphological features from H&E or IF images. Use when processing tissue images for spatial transcriptomics.
Process and analyze tissue images from spatial transcriptomics data using Squidpy. Extract image features, segment cells/nuclei, and compute morphological features from H&E or IF images. Use when processing tissue images for spatial transcriptomics.
Before using code patterns, verify installed versions match. If versions differ:
Python: pip show <package> then help(module.function) to check signatures
If code throws ImportError, AttributeError, or TypeError, introspect the installed
package and adapt the example to match the actual API rather than retrying.
Image Analysis for Spatial Transcriptomics
"Segment cells in my tissue image" → Extract image features, segment nuclei/cells, and compute morphological features from H&E or immunofluorescence images paired with spatial data.
Python: squidpy.im.process(), squidpy.im.segment() with Cellpose backend
Extract features and segment tissue images in spatial transcriptomics data.
# Get image from Visium data
library_id = list(adata.uns['spatial'].keys())[0]
img_dict = adata.uns['spatial'][library_id]['images']
# High and low resolution images
hires = img_dict['hires']
lowres = img_dict['lowres']
print(f'Hires shape: {hires.shape}')
print(f'Lowres shape: {lowres.shape}')
# Get scale factors
scalef = adata.uns['spatial'][library_id]['scalefactors']
spot_diameter = scalef['spot_diameter_fullres']
hires_scale = scalef['tissue_hires_scalef']
Create ImageContainer
Goal: Wrap tissue images in Squidpy's ImageContainer for structured access and feature extraction.
Approach: Initialize an ImageContainer from the AnnData image data or a TIFF file.
# Squidpy's ImageContainer for organized image handling
img = sq.im.ImageContainer(adata.uns['spatial'][library_id]['images']['hires'])
print(img)
# Or load from file
img = sq.im.ImageContainer('tissue_image.tif')
# Access the image array
arr = img['image'].values
Extract Image Features per Spot
Goal: Compute image-derived features (summary statistics, texture) for each spatial spot.
Approach: Use Squidpy's calculate_image_features to extract per-spot features from the tissue image within each spot's footprint.
# Calculate image features for each spot
sq.im.calculate_image_features(
adata,
img,
features=['summary', 'histogram', 'texture'],
key_added='img_features',
spot_scale=1.0, # Fraction of spot diameter
n_jobs=4,
)
# Features stored in adata.obsm['img_features']print(f"Image features shape: {adata.obsm['img_features'].shape}")