diff --git a/.gitignore b/.gitignore
index ef79da47..45431d45 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,6 +6,7 @@ dist/
*.egg-info/
site/
venv/
+**/.vscode
.ipynb_checkpoints
examples/notebooks/dataset
examples/notebooks/CIFAR10_Dataset
diff --git a/CONTENTS.md b/CONTENTS.md
index 6c4bfef3..7839ab9c 100644
--- a/CONTENTS.md
+++ b/CONTENTS.md
@@ -17,16 +17,19 @@
| [**CosFaceLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#cosfaceloss) | - [CosFace: Large Margin Cosine Loss for Deep Face Recognition](https://arxiv.org/pdf/1801.09414.pdf)
- [Additive Margin Softmax for Face Verification](https://arxiv.org/pdf/1801.05599.pdf)
| [**FastAPLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#fastaploss) | [Deep Metric Learning to Rank](http://openaccess.thecvf.com/content_CVPR_2019/papers/Cakir_Deep_Metric_Learning_to_Rank_CVPR_2019_paper.pdf)
| [**GeneralizedLiftedStructureLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#generalizedliftedstructureloss) | [In Defense of the Triplet Loss for Person Re-Identification](https://arxiv.org/pdf/1703.07737.pdf)
+| [**HistogramLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#histogramloss) | [Learning Deep Embeddings with Histogram Loss](https://arxiv.org/pdf/1611.00822.pdf)
| [**InstanceLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#instanceloss) | [Dual-Path Convolutional Image-Text Embeddings with Instance Loss](https://arxiv.org/pdf/1711.05535.pdf)
| [**IntraPairVarianceLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#intrapairvarianceloss) | [Deep Metric Learning with Tuplet Margin Loss](http://openaccess.thecvf.com/content_ICCV_2019/papers/Yu_Deep_Metric_Learning_With_Tuplet_Margin_Loss_ICCV_2019_paper.pdf)
| [**LargeMarginSoftmaxLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#largemarginsoftmaxloss) | [Large-Margin Softmax Loss for Convolutional Neural Networks](https://arxiv.org/pdf/1612.02295.pdf)
| [**LiftedStructreLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#liftedstructureloss) | [Deep Metric Learning via Lifted Structured Feature Embedding](https://arxiv.org/pdf/1511.06452.pdf)
+| [**ManifoldLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#manifoldloss) | [Ensemble Deep Manifold Similarity Learning using Hard Proxies](https://openaccess.thecvf.com/content_CVPR_2019/papers/Aziere_Ensemble_Deep_Manifold_Similarity_Learning_Using_Hard_Proxies_CVPR_2019_paper.pdf)
| [**MarginLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#marginloss) | [Sampling Matters in Deep Embedding Learning](https://arxiv.org/pdf/1706.07567.pdf)
| [**MultiSimilarityLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#multisimilarityloss) | [Multi-Similarity Loss with General Pair Weighting for Deep Metric Learning](http://openaccess.thecvf.com/content_CVPR_2019/papers/Wang_Multi-Similarity_Loss_With_General_Pair_Weighting_for_Deep_Metric_Learning_CVPR_2019_paper.pdf)
| [**NCALoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#ncaloss) | [Neighbourhood Components Analysis](https://www.cs.toronto.edu/~hinton/absps/nca.pdf)
| [**NormalizedSoftmaxLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#normalizedsoftmaxloss) | - [NormFace: L2 Hypersphere Embedding for Face Verification](https://arxiv.org/pdf/1704.06369.pdf)
- [Classification is a Strong Baseline for DeepMetric Learning](https://arxiv.org/pdf/1811.12649.pdf)
| [**NPairsLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#npairsloss) | [Improved Deep Metric Learning with Multi-class N-pair Loss Objective](http://www.nec-labs.com/uploads/images/Department-Images/MediaAnalytics/papers/nips16_npairmetriclearning.pdf)
| [**NTXentLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#ntxentloss) | - [Representation Learning with Contrastive Predictive Coding](https://arxiv.org/pdf/1807.03748.pdf)
- [Momentum Contrast for Unsupervised Visual Representation Learning](https://arxiv.org/pdf/1911.05722.pdf)
- [A Simple Framework for Contrastive Learning of Visual Representations](https://arxiv.org/abs/2002.05709)
+| [**P2SGradLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#p2sgradloss) | [P2SGrad: Refined Gradients for Optimizing Deep Face Models](https://arxiv.org/abs/1905.02479)
| [**PNPLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#pnploss) | [Rethinking the Optimization of Average Precision: Only Penalizing Negative Instances before Positive Ones is Enough](https://arxiv.org/pdf/2102.04640.pdf)
| [**ProxyAnchorLoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#proxyanchorloss) | [Proxy Anchor Loss for Deep Metric Learning](https://arxiv.org/pdf/2003.13911.pdf)
| [**ProxyNCALoss**](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#proxyncaloss) | [No Fuss Distance Metric Learning using Proxies](https://arxiv.org/pdf/1703.07464.pdf)
diff --git a/README.md b/README.md
index 26d568ae..f8eb0c7b 100644
--- a/README.md
+++ b/README.md
@@ -18,13 +18,15 @@
## News
+**June 18**: v2.2.0
+- Added [ManifoldLoss](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#manifoldloss) and [P2SGradLoss](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#p2sgradloss).
+- Added a `symmetric` flag to [SelfSupervisedLoss](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#selfsupervisedloss).
+- See the [release notes](https://github.com/KevinMusgrave/pytorch-metric-learning/releases/tag/v2.2.0).
+- Thank you [domenicoMuscill0](https://github.com/domenicoMuscill0).
+
**April 5**: v2.1.0
- Added [PNPLoss](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#pnploss)
-- Thanks to contributor [interestingzhuo](https://github.com/interestingzhuo).
-
-**January 29**: v2.0.0
-- Added SelfSupervisedLoss, plus various API improvements. See the [release notes](https://github.com/KevinMusgrave/pytorch-metric-learning/releases/tag/v2.0.0).
-- Thanks to contributor [cwkeam](https://github.com/cwkeam).
+- Thanks you [interestingzhuo](https://github.com/interestingzhuo).
## Documentation
@@ -225,6 +227,7 @@ Thanks to the contributors who made pull requests!
| Contributor | Highlights |
| -- | -- |
+|[domenicoMuscill0](https://github.com/domenicoMuscill0)| - [ManifoldLoss](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#manifoldloss)
- [P2SGradLoss](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#p2sgradloss)
|[mlopezantequera](https://github.com/mlopezantequera) | - Made the [testers](https://kevinmusgrave.github.io/pytorch-metric-learning/testers) work on any combination of query and reference sets
- Made [AccuracyCalculator](https://kevinmusgrave.github.io/pytorch-metric-learning/accuracy_calculation/) work with arbitrary label comparisons |
|[cwkeam](https://github.com/cwkeam) | - [SelfSupervisedLoss](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#selfsupervisedloss)
- [VICRegLoss](https://kevinmusgrave.github.io/pytorch-metric-learning/losses/#vicregloss)
- Added mean reciprocal rank accuracy to [AccuracyCalculator](https://kevinmusgrave.github.io/pytorch-metric-learning/accuracy_calculation/)
- BaseLossWrapper|
|[marijnl](https://github.com/marijnl)| - [BatchEasyHardMiner](https://kevinmusgrave.github.io/pytorch-metric-learning/miners/#batcheasyhardminer)
- [TwoStreamMetricLoss](https://kevinmusgrave.github.io/pytorch-metric-learning/trainers/#twostreammetricloss)
- [GlobalTwoStreamEmbeddingSpaceTester](https://kevinmusgrave.github.io/pytorch-metric-learning/testers/#globaltwostreamembeddingspacetester)
- [Example using trainers.TwoStreamMetricLoss](https://github.com/KevinMusgrave/pytorch-metric-learning/blob/master/examples/notebooks/TwoStreamMetricLoss.ipynb) |
@@ -273,6 +276,7 @@ This library contains code that has been adapted and modified from the following
- https://github.com/ronekko/deep_metric_learning
- https://github.com/tjddus9597/Proxy-Anchor-CVPR2020
- http://kaizhao.net/regularface
+- https://github.com/nii-yamagishilab/project-NN-Pytorch-scripts
### Logo
Thanks to [Jeff Musgrave](https://www.designgenius.ca/) for designing the logo.
diff --git a/docs/losses.md b/docs/losses.md
index b0719258..d5c1f4b4 100644
--- a/docs/losses.md
+++ b/docs/losses.md
@@ -424,6 +424,26 @@ losses.InstanceLoss(gamma=64, **kwargs)
* **gamma**: The cosine similarity matrix is scaled by this amount.
+## HistogramLoss
+[Learning Deep Embeddings with Histogram Loss](https://arxiv.org/pdf/1611.00822.pdf)
+```python
+losses.HistogramLoss(n_bins=None, delta=None)
+```
+
+**Parameters**:
+
+* **n_bins**: The number of bins used to construct the histogram. Default is 100 when both `n_bins` and `delta` are `None`.
+* **delta**: The mesh of the uniform partition of the interval [-1, 1] used to construct the histogram. If not set the value of n_bins will be used.
+
+**Default distance**:
+
+ - [```CosineSimilarity()```](distances.md#cosinesimilarity)
+
+**Default reducer**:
+
+ - This loss returns an **already reduced** loss.
+
+
## IntraPairVarianceLoss
[Deep Metric Learning with Tuplet Margin Loss](http://openaccess.thecvf.com/content_ICCV_2019/papers/Yu_Deep_Metric_Learning_With_Tuplet_Margin_Loss_ICCV_2019_paper.pdf){target=_blank}
```python
@@ -545,6 +565,57 @@ losses.LiftedStructureLoss(neg_margin=1, pos_margin=0, **kwargs):
* **loss**: The loss per positive pair in the batch. Reduction type is ```"pos_pair"```.
+## ManifoldLoss
+
+[Ensemble Deep Manifold Similarity Learning using Hard Proxies](https://openaccess.thecvf.com/content_CVPR_2019/papers/Aziere_Ensemble_Deep_Manifold_Similarity_Learning_Using_Hard_Proxies_CVPR_2019_paper.pdf)
+
+```python
+losses.ManifoldLoss(
+ l: int,
+ K: int = 50,
+ lambdaC: float = 1.0,
+ alpha: float = 0.8,
+ margin: float = 5e-4,
+ **kwargs
+ )
+```
+
+**Parameters**
+
+- **l**: embedding size.
+
+- **K**: number of proxies.
+
+- **lambdaC**: regularization weight. Used in the formula `loss = intrinsic_loss + lambdaC*context_loss`.
+ If `lambdaC=0`, then it uses only the intrinsic loss. If `lambdaC=np.inf`, then it uses only the context loss.
+
+- **alpha**: parameter of the Random Walk. Must be in the range `(0,1)`. It specifies the amount of similarity between neighboring nodes.
+
+- **margin**: margin used in the calculation of the loss.
+
+
+Example usage:
+```python
+loss_fn = ManifoldLoss(128)
+
+# use random cluster centers
+loss = loss_fn(embeddings)
+# or specify indices of embeddings to use as cluster centers
+loss = loss_fn(embeddings, indices_tuple=indices)
+```
+
+**Important notes**
+
+`labels`, `ref_emb`, and `ref_labels` are not supported for this loss function.
+
+In addition, `indices_tuple` is **not** for the output of miners. Instead, it is for a list of indices of embeddings to be used as cluster centers.
+
+
+**Default reducer**:
+
+ - This loss returns an **already reduced** loss.
+
+
## MarginLoss
[Sampling Matters in Deep Embedding Learning](https://arxiv.org/pdf/1706.07567.pdf){target=_blank}
```python
@@ -761,6 +832,37 @@ losses.NTXentLoss(temperature=0.07, **kwargs)
* **loss**: The loss per positive pair in the batch. Reduction type is ```"pos_pair"```.
+
+## P2SGradLoss
+[P2SGrad: Refined Gradients for Optimizing Deep Face Models](https://arxiv.org/abs/1905.02479)
+```python
+losses.P2SGradLoss(descriptors_dim, num_classes, **kwargs)
+```
+
+**Parameters**
+
+- **descriptors_dim**: The embedding size.
+
+- **num_classes**: The number of classes in your training dataset.
+
+
+Example usage:
+```python
+loss_fn = P2SGradLoss(128, 10)
+loss = loss_fn(embeddings, labels)
+```
+
+**Important notes**
+
+`indices_tuple`, `ref_emb`, and `ref_labels` are not supported for this loss function.
+
+
+**Default reducer**:
+
+ - This loss returns an **already reduced** loss.
+
+
+
## PNPLoss
[Rethinking the Optimization of Average Precision: Only Penalizing Negative Instances before Positive Ones is Enough](https://arxiv.org/pdf/2102.04640.pdf){target=_blank}
```python
@@ -849,14 +951,31 @@ loss_optimizer.step()
## SelfSupervisedLoss
-A common use case is to have `embeddings` and `ref_emb` be augmented versions of each other. For most losses, you have to create labels to indicate which `embeddings` correspond with which `ref_emb`. `SelfSupervisedLoss` automates this.
+A common use case is to have `embeddings` and `ref_emb` be augmented versions of each other. For most losses, you have to create labels to indicate which `embeddings` correspond with which `ref_emb`.
+
+`SelfSupervisedLoss` is a wrapper that takes care of this by creating labels internally. It assumes that:
+
+- `ref_emb[i]` is an augmented version of `embeddings[i]`.
+- `ref_emb[i]` is the only augmented version of `embeddings[i]` in the batch.
```python
+losses.SelfSupervisedLoss(loss, symmetric=True, **kwargs)
+```
+
+**Parameters**:
+
+* **loss**: The loss function to be wrapped.
+* **symmetric**: If `True`, then the embeddings in both `embeddings` and `ref_emb` are used as anchors. If `False`, then only the embeddings in `embeddings` are used as anchors.
+
+Example usage:
+
+```
loss_fn = losses.TripletMarginLoss()
loss_fn = SelfSupervisedLoss(loss_fn)
loss = loss_fn(embeddings, ref_emb)
```
+
??? "Supported Loss Functions"
- [AngularLoss](losses.md#angularloss)
- [CircleLoss](losses.md#circleloss)
diff --git a/src/pytorch_metric_learning/__init__.py b/src/pytorch_metric_learning/__init__.py
index 8a124bf6..55e47090 100644
--- a/src/pytorch_metric_learning/__init__.py
+++ b/src/pytorch_metric_learning/__init__.py
@@ -1 +1 @@
-__version__ = "2.2.0"
+__version__ = "2.3.0"
diff --git a/src/pytorch_metric_learning/losses/__init__.py b/src/pytorch_metric_learning/losses/__init__.py
index 10e841f1..a0ba7407 100644
--- a/src/pytorch_metric_learning/losses/__init__.py
+++ b/src/pytorch_metric_learning/losses/__init__.py
@@ -8,6 +8,7 @@
from .cross_batch_memory import CrossBatchMemory
from .fast_ap_loss import FastAPLoss
from .generic_pair_loss import GenericPairLoss
+from .histogram_loss import HistogramLoss
from .instance_loss import InstanceLoss
from .intra_pair_variance_loss import IntraPairVarianceLoss
from .large_margin_softmax_loss import LargeMarginSoftmaxLoss
diff --git a/src/pytorch_metric_learning/losses/histogram_loss.py b/src/pytorch_metric_learning/losses/histogram_loss.py
new file mode 100644
index 00000000..44899fcb
--- /dev/null
+++ b/src/pytorch_metric_learning/losses/histogram_loss.py
@@ -0,0 +1,80 @@
+import torch
+
+from ..distances import CosineSimilarity
+from ..utils import common_functions as c_f
+from ..utils import loss_and_miner_utils as lmu
+from .base_metric_loss_function import BaseMetricLossFunction
+
+
+def filter_pairs(*tensors: torch.Tensor):
+ t = torch.stack(tensors)
+ t, _ = torch.sort(t, dim=0)
+ t = torch.unique(t, dim=1)
+ return t.tolist()
+
+
+class HistogramLoss(BaseMetricLossFunction):
+ def __init__(self, n_bins: int = None, delta: float = None, **kwargs):
+ super().__init__(**kwargs)
+ if delta is not None and n_bins is not None:
+ assert (
+ delta == 2 / n_bins
+ ), f"delta and n_bins must satisfy the equation delta = 2/n_bins.\nPassed values are delta={delta} and n_bins={n_bins}"
+
+ if delta is None and n_bins is None:
+ n_bins = 100
+
+ self.delta = delta if delta is not None else 2 / n_bins
+ self.add_to_recordable_attributes(name="delta", is_stat=True)
+
+ def compute_loss(self, embeddings, labels, indices_tuple, ref_emb, ref_labels):
+ c_f.labels_or_indices_tuple_required(labels, indices_tuple)
+ c_f.ref_not_supported(embeddings, labels, ref_emb, ref_labels)
+ indices_tuple = lmu.convert_to_triplets(
+ indices_tuple, labels, ref_labels, t_per_anchor="all"
+ )
+ anchor_idx, positive_idx, negative_idx = indices_tuple
+ if len(anchor_idx) == 0:
+ return self.zero_losses()
+ mat = self.distance(embeddings, ref_emb)
+
+ anchor_positive_idx = filter_pairs(anchor_idx, positive_idx)
+ anchor_negative_idx = filter_pairs(anchor_idx, negative_idx)
+ ap_dists = mat[anchor_positive_idx]
+ an_dists = mat[anchor_negative_idx]
+
+ p_pos = self.compute_density(ap_dists)
+ phi = torch.cumsum(p_pos, dim=0)
+
+ p_neg = self.compute_density(an_dists)
+ return {
+ "loss": {
+ "losses": torch.sum(p_neg * phi),
+ "indices": None,
+ "reduction_type": "already_reduced",
+ }
+ }
+
+ def compute_density(self, distances):
+ size = distances.size(0)
+ r_star = torch.floor(
+ (distances.float() + 1) / self.delta
+ ) # Indices of the bins containing the values of the distances
+ r_star = c_f.to_device(r_star, tensor=distances, dtype=torch.long)
+
+ delta_ijr_a = (distances + 1 - r_star * self.delta) / self.delta
+ delta_ijr_b = ((r_star + 1) * self.delta - 1 - distances) / self.delta
+ delta_ijr_a = c_f.to_dtype(delta_ijr_a, tensor=distances)
+ delta_ijr_b = c_f.to_dtype(delta_ijr_b, tensor=distances)
+
+ density = torch.zeros(round(1 + 2 / self.delta))
+ density = c_f.to_device(density, tensor=distances, dtype=distances.dtype)
+
+ # For each node sum the contributions of the bins whose ending node is this one
+ density.scatter_add_(0, r_star + 1, delta_ijr_a)
+ # For each node sum the contributions of the bins whose starting node is this one
+ density.scatter_add_(0, r_star, delta_ijr_b)
+ return density / size
+
+ def get_default_distance(self):
+ return CosineSimilarity()
diff --git a/tests/losses/test_histogram_loss.py b/tests/losses/test_histogram_loss.py
new file mode 100644
index 00000000..aeeb54af
--- /dev/null
+++ b/tests/losses/test_histogram_loss.py
@@ -0,0 +1,170 @@
+import unittest
+
+import torch
+from numpy.testing import assert_almost_equal
+
+from pytorch_metric_learning.losses import HistogramLoss
+from pytorch_metric_learning.utils import common_functions as c_f
+
+from .. import TEST_DEVICE, TEST_DTYPES
+
+
+######################################
+#######ORIGINAL IMPLEMENTATION########
+######################################
+# DIRECTLY COPIED from https://github.com/valerystrizh/pytorch-histogram-loss/blob/master/losses.py.
+# This code is copied from the official PyTorch implementation
+# so that we can make sure our implementation returns the same result.
+# Some minor changes were made to avoid errors during testing.
+# Every change in the original code is reported and explained.
+class OriginalImplementationHistogramLoss(torch.nn.Module):
+ def __init__(self, num_steps, cuda=True):
+ super(OriginalImplementationHistogramLoss, self).__init__()
+ self.step = 2 / (num_steps - 1)
+ self.eps = 1 / num_steps
+ self.cuda = cuda
+ self.t = torch.arange(-1, 1 + self.step, self.step).view(-1, 1)
+ self.tsize = self.t.size()[0]
+ if self.cuda:
+ self.t = self.t.cuda()
+
+ def forward(self, features, classes):
+ def histogram(inds, size):
+ s_repeat_ = s_repeat.clone()
+ inds = c_f.to_device(inds, tensor=s_repeat_floor) # Added to avoid errors
+ self.t = c_f.to_device(
+ self.t, tensor=s_repeat_floor
+ ) # Added to avoid errors
+ indsa = (
+ (s_repeat_floor - (self.t - self.step) > -self.eps)
+ & (s_repeat_floor - (self.t - self.step) < self.eps)
+ & inds
+ )
+ assert (
+ indsa.nonzero().size()[0] == size
+ ), "Another number of bins should be used"
+ zeros = torch.zeros((1, indsa.size()[1])).to(
+ device=indsa.device, dtype=torch.uint8
+ )
+ if self.cuda:
+ zeros = zeros.cuda()
+ indsb = torch.cat((indsa, zeros))[1:, :].to(
+ dtype=torch.bool
+ ) # Added to avoid bug with masks of uint8
+ s_repeat_[~(indsb | indsa)] = 0
+ # indsa corresponds to the first condition of the second equation of the paper
+ self.t = self.t.to(
+ dtype=s_repeat_.dtype
+ ) # Added to avoid errors when using Half precision
+ s_repeat_[indsa] = (s_repeat_ - self.t + self.step)[indsa] / self.step
+ # indsb corresponds to the second condition of the second equation of the paper
+ s_repeat_[indsb] = (-s_repeat_ + self.t + self.step)[indsb] / self.step
+
+ return s_repeat_.sum(1) / size
+
+ classes_size = classes.size()[0]
+ classes_eq = (
+ classes.repeat(classes_size, 1)
+ == classes.view(-1, 1).repeat(1, classes_size)
+ ).data
+ dists = torch.mm(features, features.transpose(0, 1))
+ assert (
+ (dists > 1 + self.eps).sum().item() + (dists < -1 - self.eps).sum().item()
+ ) == 0, "L2 normalization should be used"
+ s_inds = torch.triu(torch.ones(classes_eq.size()), 1).byte()
+ if self.cuda:
+ s_inds = s_inds.cuda()
+ classes_eq = classes_eq.to(
+ device=s_inds.device
+ ) # Added to avoid errors when using only cpu
+ pos_inds = classes_eq[s_inds].repeat(self.tsize, 1)
+ neg_inds = ~classes_eq[s_inds].repeat(self.tsize, 1)
+ pos_size = classes_eq[s_inds].sum().item()
+ neg_size = (~classes_eq[s_inds]).sum().item()
+ s = dists[s_inds].view(1, -1)
+ s_repeat = s.repeat(self.tsize, 1)
+ s_repeat_floor = (torch.floor(s_repeat.data / self.step) * self.step).float()
+
+ histogram_pos = histogram(pos_inds, pos_size)
+ assert_almost_equal(
+ histogram_pos.sum().item(),
+ 1,
+ decimal=1,
+ err_msg="Not good positive histogram",
+ verbose=True,
+ )
+ histogram_neg = histogram(neg_inds, neg_size)
+ assert_almost_equal(
+ histogram_neg.sum().item(),
+ 1,
+ decimal=1,
+ err_msg="Not good negative histogram",
+ verbose=True,
+ )
+ histogram_pos_repeat = histogram_pos.view(-1, 1).repeat(
+ 1, histogram_pos.size()[0]
+ )
+ histogram_pos_inds = torch.tril(
+ torch.ones(histogram_pos_repeat.size()), -1
+ ).byte()
+ if self.cuda:
+ histogram_pos_inds = histogram_pos_inds.cuda()
+ histogram_pos_repeat[histogram_pos_inds] = 0
+ histogram_pos_cdf = histogram_pos_repeat.sum(0)
+ loss = torch.sum(histogram_neg * histogram_pos_cdf)
+
+ return loss
+
+
+class TestHistogramLoss(unittest.TestCase):
+ def test_histogram_loss(self):
+ batch_size = 32
+ embedding_size = 64
+ for dtype in TEST_DTYPES:
+ num_steps = 5 if dtype == torch.float16 else 21
+ num_bins = num_steps - 1
+ loss_func = HistogramLoss(n_bins=num_bins)
+ original_loss_func = OriginalImplementationHistogramLoss(
+ num_steps=num_steps, cuda=False
+ )
+
+ # test multiple times
+ for _ in range(2):
+ embeddings = torch.randn(
+ batch_size,
+ embedding_size,
+ requires_grad=True,
+ dtype=dtype,
+ ).to(TEST_DEVICE)
+ labels = torch.randint(0, 5, size=(batch_size,))
+
+ loss = loss_func(embeddings, labels)
+ correct_loss = original_loss_func(
+ torch.nn.functional.normalize(embeddings), labels
+ )
+
+ rtol = 1e-2 if dtype == torch.float16 else 1e-5
+ self.assertTrue(torch.isclose(loss, correct_loss, rtol=rtol))
+
+ loss.backward()
+
+ def test_with_no_valid_triplets(self):
+ loss_func = HistogramLoss(n_bins=4)
+ for dtype in TEST_DTYPES:
+ embeddings = torch.randn(
+ 5,
+ 32,
+ requires_grad=True,
+ dtype=dtype,
+ ).to(TEST_DEVICE)
+ labels = torch.LongTensor([0, 1, 2, 3, 4])
+ loss = loss_func(embeddings, labels)
+ self.assertEqual(loss, 0)
+ loss.backward()
+
+ def test_assertion_raises(self):
+ with self.assertRaises(AssertionError):
+ _ = HistogramLoss(n_bins=1, delta=0.5)
+
+ with self.assertRaises(AssertionError):
+ _ = HistogramLoss(n_bins=10, delta=0.4)