Houdini 20.0 Nodes Geometry nodes

Labs AV Analyze Images 5.0 geometry node

Match all features between candidate image pairs using Alicevision.

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The objective of this step is to extract distinctive groups of pixels that are, to some extent, invariant to changing camera viewpoints during image acquisition, and to match all features between candidate image pairs.


Requires Meshroom/AliceVision version 2021.1.0.




Start the cooking process for this step.

Manual Mode

This toggle controls if the node should automatically recook if any dependencies have changed.

Use Log

This toggle controls if the status of the current node should be printed to the console. This is useful for getting a quick overview of the progress.

Feature Extraction

Describer Types

Describer types used to describe an image.

Describer Preset

Control the ImageDescriber configuration (low, medium, normal, high, ultra). Configuration “ultra” can take long time !

Force CPU Extraction

Use only CPU feature extraction.

Image Matching

Min Number of Images

Minimal number of images to use the vocabulary tree. If we have less features than this threshold, we will compute all matching combinations.

Max Descriptors

Limit the number of descriptors you load per image. Zero means no limit.

Number of Matches

The number of matches to retrieve for each image (If 0 it will retrieve all the matches).

Feature Matching

Describer Types

Describer types used to describe an image.

Photometric Matching Method

For Scalar based regions descriptor – ' BRUTE_FORCE_L2: L2 BruteForce matching'

' ANN_L2: L2 Approximate Nearest Neighbor matching'

' CASCADE_HASHING_L2: L2 Cascade Hashing matching'

' FAST_CASCADE_HASHING_L2: L2 Cascade Hashing with precomputed hashed regions (faster than CASCADE_HASHING_L2 but use more memory)

For Binary based descriptor – ' BRUTE_FORCE_HAMMING: BruteForce Hamming matching'

Geometric Error

Maximum error allowed for features matching during geometric verification.

Geometric Filter type

Geometric validation method to filter features matches.

Distance Ratio

Distance ratio to discard non meaningful matches.

Max Iteration

aximum number of iterations allowed in ransac step.

Max Matches

Maximum number of matches to keep.

Save Putative Matches

Putative matches.

Guided Matches

The found model to improve the pairwise correspondences.

Export Debug Files

Debug files (svg, dot).



The environment used for launching the AliceVision utilities commandline. Note that this is a python expression and should be modified only through “Edit Expression”.


Geometry nodes