open3d.ml.tf.models.PointTransformer

class open3d.ml.tf.models.PointTransformer(*args, **kwargs)

Semantic Segmentation model. Based on PointTransformer architecture https://arxiv.org/pdf/2012.09164.pdf

Uses Encoder-Decoder architecture with Transformer layers.

name

Name of model. Default to “PointTransformer”.

blocks

Number of Bottleneck layers.

in_channels

Number of features(default 6).

num_classes

Number of classes.

voxel_size

Voxel length for subsampling.

max_voxels

Maximum number of voxels.

augment

dictionary for augmentation.

__init__(name='PointTransformer', blocks=[2, 2, 2, 2, 2], in_channels=6, num_classes=13, voxel_size=0.04, max_voxels=80000, augment=None, **kwargs)

Initialize self. See help(type(self)) for accurate signature.

call(inputs, training=False)

Forward pass for the model.

Parameters
  • inputs – A dict object for inputs with following keys point (tf.float32): Input pointcloud (N,3) feat (tf.float32): Input features (N, 3) row_splits (tf.int64): row splits for batches (b+1,)

  • training – training mode of model.

Returns

Returns the probability distribution.

get_batch_gen(dataset, steps_per_epoch=None, batch_size=1)
get_loss(sem_seg_loss, results, inputs)

Calculate the loss on output of the model.

Parameters
  • sem_seg_loss – Object of type SemSegLoss.

  • results – Output of the model.

  • inputs – Input of the model.

  • device – device(cpu or cuda).

Returns

Returns loss, labels and scores.

get_optimizer(cfg_pipeline)

Returns an optimizer object for the model.

Parameters

cfg_pipeline – A Config object with the configuration of the pipeline.

Returns

Returns a new optimizer object.

inference_begin(data)

Function called right before running inference.

Parameters

data – A data from the dataset.

inference_end(results)

This function is called after the inference.

This function can be implemented to apply post-processing on the network outputs.

Parameters

results – The model outputs as returned by the call() function. Post-processing is applied on this object.

Returns

Returns True if the inference is complete and otherwise False. Returning False can be used to implement inference for large point clouds which require multiple passes.

inference_preprocess()

This function prepares the inputs for the model.

Returns

The inputs to be consumed by the call() function of the model.

preprocess(data, attr)

Data preprocessing function.

This function is called before training to preprocess the data from a dataset. It consists of subsampling pointcloud with voxelization, augmentation and normalizing the features.

Parameters
  • data – A sample from the dataset.

  • attr – The corresponding attributes.

Returns

Returns the preprocessed data

transform(point, feat, label, splits)

Transform function for the point cloud and features.

This function is called after preprocess method by dataset generator. It consists of mapping data to dict.

Parameters
  • point – Input pointcloud.

  • feat – Input features.

  • label – Input labels.

  • splits – row_splits defining batches.

Returns

Returns dictionary data with keys (point, feat, label, row_splits).