From 22792f756a0dad940f4911e49e66f750bfa567f6 Mon Sep 17 00:00:00 2001
From: BRAUN REMI <remi.braun@unistra.fr>
Date: Tue, 3 Sep 2024 18:11:45 +0200
Subject: [PATCH] OPTIM: Save nodata of DIMAP V2 products on disk to avoid
 recomputing it (`features.rasetrize` could be a heavy computation that
 shouldn't be done twice)

---
 CHANGES.md                                    |  1 +
 eoreader/products/optical/dimap_v2_product.py | 28 +++++++++++++------
 2 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/CHANGES.md b/CHANGES.md
index b330adbe..33f82c0a 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -7,6 +7,7 @@
 - FIX: Resolve the inversion of resolution and pixel size between `stripmap` and `sliding_spotlight` types for `Capella` products
 - FIX: Get better window name (if available) when writing bands on disk (in tmp folder) 
 - OPTIM: Use default (and optimized) predictor in `rasters.write` if SNAP is version 10 or higher ([#173](https://github.com/sertit/eoreader/issues/173))
+- OPTIM: Save nodata of DIMAP V2 products on disk to avoid recomputing it (`features.rasetrize` could be a heavy computation that shouldn't be done twice)
 - COMPAT: EOReader works correctly with SNAP 10 ([#165](https://github.com/sertit/eoreader/issues/165))
 
 ## 0.21.2 (2024-07-30)
diff --git a/eoreader/products/optical/dimap_v2_product.py b/eoreader/products/optical/dimap_v2_product.py
index 8962f25f..c6deb320 100644
--- a/eoreader/products/optical/dimap_v2_product.py
+++ b/eoreader/products/optical/dimap_v2_product.py
@@ -737,8 +737,10 @@ def _manage_nodata(
         )
 
         # Get detector footprint to deduce the outside nodata
+        LOGGER.debug("Load nodata")
         nodata = self._load_nodata(width, height, vec_tr, **kwargs)
 
+        LOGGER.debug("Set nodata mask")
         return self._set_nodata_mask(band_arr, nodata)
 
     @cache
@@ -1086,15 +1088,25 @@ def _load_nodata(
         if all(nodata_det.is_empty):
             return np.zeros((1, height, width), dtype=np.uint8)
         else:
-            # Rasterize nodata
-            return features.rasterize(
-                nodata_det.geometry,
-                out_shape=(height, width),
-                fill=self._mask_true,  # Outside ROI = nodata (inverted compared to the usual)
-                default_value=self._mask_false,  # Inside ROI = not nodata
-                transform=trf,
-                dtype=np.uint8,
+            nodata_path, nodata_exists = self._get_out_path(
+                f"{self.condensed_name}_nodata_{int(width)}x{int(height)}.npy"
             )
+            if not nodata_exists:
+                LOGGER.debug("Rasterizing ROI mask to the extent of ")
+                # Rasterize nodata
+                nodata = features.rasterize(
+                    nodata_det.geometry,
+                    out_shape=(height, width),
+                    fill=self._mask_true,  # Outside ROI = nodata (inverted compared to the usual)
+                    default_value=self._mask_false,  # Inside ROI = not nodata
+                    transform=trf,
+                    dtype=np.uint8,
+                )
+                np.save(str(nodata_path), nodata)
+            else:
+                nodata = np.load(str(nodata_path))
+
+            return nodata
 
     def _get_tile_path(self) -> AnyPathType:
         """