Create chart_output_hflip.py

3rdparty/densepose/converters/chart_output_hflip.py

@@ -0,0 +1,71 @@
+# Copyright (c) Facebook, Inc. and its affiliates.
+from dataclasses import fields
+import torch
+
+from densepose.structures import DensePoseChartPredictorOutput, DensePoseTransformData
+
+
+def densepose_chart_predictor_output_hflip(
+    densepose_predictor_output: DensePoseChartPredictorOutput,
+    transform_data: DensePoseTransformData,
+) -> DensePoseChartPredictorOutput:
+    """
+    Change  to take into account a Horizontal flip.
+    """
+    if len(densepose_predictor_output) > 0:
+
+        PredictorOutput = type(densepose_predictor_output)
+        output_dict = {}
+
+        for field in fields(densepose_predictor_output):
+            field_value = getattr(densepose_predictor_output, field.name)
+            # flip tensors
+            if isinstance(field_value, torch.Tensor):
+                setattr(densepose_predictor_output, field.name, torch.flip(field_value, [3]))
+
+        densepose_predictor_output = _flip_iuv_semantics_tensor(
+            densepose_predictor_output, transform_data
+        )
+        densepose_predictor_output = _flip_segm_semantics_tensor(
+            densepose_predictor_output, transform_data
+        )
+
+        for field in fields(densepose_predictor_output):
+            output_dict[field.name] = getattr(densepose_predictor_output, field.name)
+
+        return PredictorOutput(**output_dict)
+    else:
+        return densepose_predictor_output
+
+
+def _flip_iuv_semantics_tensor(
+    densepose_predictor_output: DensePoseChartPredictorOutput,
+    dp_transform_data: DensePoseTransformData,
+) -> DensePoseChartPredictorOutput:
+    point_label_symmetries = dp_transform_data.point_label_symmetries
+    uv_symmetries = dp_transform_data.uv_symmetries
+
+    N, C, H, W = densepose_predictor_output.u.shape
+    u_loc = (densepose_predictor_output.u[:, 1:, :, :].clamp(0, 1) * 255).long()
+    v_loc = (densepose_predictor_output.v[:, 1:, :, :].clamp(0, 1) * 255).long()
+    Iindex = torch.arange(C - 1, device=densepose_predictor_output.u.device)[
+        None, :, None, None
+    ].expand(N, C - 1, H, W)
+    densepose_predictor_output.u[:, 1:, :, :] = uv_symmetries["U_transforms"][Iindex, v_loc, u_loc]
+    densepose_predictor_output.v[:, 1:, :, :] = uv_symmetries["V_transforms"][Iindex, v_loc, u_loc]
+
+    for el in ["fine_segm", "u", "v"]:
+        densepose_predictor_output.__dict__[el] = densepose_predictor_output.__dict__[el][
+            :, point_label_symmetries, :, :
+        ]
+    return densepose_predictor_output
+
+
+def _flip_segm_semantics_tensor(
+    densepose_predictor_output: DensePoseChartPredictorOutput, dp_transform_data
+):
+    if densepose_predictor_output.coarse_segm.shape[1] > 2:
+        densepose_predictor_output.coarse_segm = densepose_predictor_output.coarse_segm[
+            :, dp_transform_data.mask_label_symmetries, :, :
+        ]
+    return densepose_predictor_output