Add quickpreview module, fix cutline polygons edge-case

contrib/mergepreview/README.md

@@ -0,0 +1,29 @@
+# Merge Preview
+
+Quickly projects drone images on a map by using georeferencing, camera angles and a global DTM. The images are then merged using ODM's split-merge algorithms.
+
+Quality is obviously not good, works only for nadir-only images and requires the images to have gimbal/camera angle information (not all drones provide this information).
+
+Usage:
+
+```
+# Install DDB (required for geoprojection)
+
+curl -fsSL https://get.dronedb.app -o get-ddb.sh
+sh get-ddb.sh
+
+# Run
+
+python3 mergepreview.py -i images/*.JPG --size 25%
+```
+
+## Example
+
+![screen](https://user-images.githubusercontent.com/1951843/134249725-e178489a-e271-4244-abed-e624cd510b88.png)
+
+
+[Sheffield Park](https://community.opendronemap.org/t/sheffield-park-1/58) images processed with this script.
+
+## Disclaimer
+
+This script is highly experimental. We welcome contributions to improve it.

contrib/mergepreview/mergepreview.py

@@ -0,0 +1,126 @@
+import argparse
+import sys
+sys.path.append("../../")
+
+import os
+from opendm import orthophoto
+from opendm.cutline import compute_cutline
+import glob
+from opendm.system import run
+from opendm import log
+import shutil
+
+
+parser = argparse.ArgumentParser(description='Quick Merge Preview')
+parser.add_argument('input',
+                    metavar='<paths>',
+                    nargs='+',
+                    help='Path to input images or image folder')
+parser.add_argument('--size', '-s',
+                    metavar='<percentage>',
+                    type=str,
+                    help='Size in percentage terms',
+                    default='25%')
+parser.add_argument('--force', '-f', 
+                        action='store_true',
+                        default=False, 
+                        help="Force remove existing directories")
+
+args = parser.parse_args()
+
+try:
+    log.ODM_INFO("Checking for DDB...")
+    run("ddb --version")
+except:
+    log.ODM_ERROR("ddb is not installed. Install it first: https://docs.dronedb.app")
+
+if len(args.input) == 1 and os.path.isdir(args.input[0]):
+    input_images = []
+    for ext in ["JPG", "JPEG", "TIF", "tiff", "tif", "TIFF"]:
+        input_images += glob.glob(os.path.join(args.input[0], "*.%s" % ext))
+else:
+    input_images = args.input
+
+log.ODM_INFO("Processing %s images" % len(input_images))
+
+if len(input_images) == 0:
+    log.ODM_ERROR("No images")
+    exit(1)
+
+cwd_path = os.path.dirname(input_images[0])
+tmp_path = os.path.join(cwd_path, "tmp")
+if os.path.isdir(tmp_path):
+    if args.force:
+        log.ODM_INFO("Removing previous directory %s" % tmp_path)
+        shutil.rmtree(tmp_path)
+    else:
+        log.ODM_ERROR("%s exists. Pass --force to override." % tmp_path)
+        exit(1)
+
+os.makedirs(tmp_path)
+
+for f in input_images:
+    name, _ = os.path.splitext(os.path.basename(f))
+    geojson = os.path.join(tmp_path, "%s.geojson" % name)
+    gpkg = os.path.join(tmp_path, "%s.gpkg" % name)
+
+    run("ddb geoproj \"%s\" \"%s\" -s \"%s\"" % (tmp_path, f, args.size))
+
+    # Bounds (GPKG)
+    run("ddb info --format geojson --geometry polygon \"%s\" > \"%s\"" % (f, geojson))
+    run("ogr2ogr \"%s\" \"%s\"" % (gpkg, geojson))
+
+log.ODM_INFO("Computing cutlines")
+
+projected_images = glob.glob(os.path.join(tmp_path, "*.tif"))
+all_orthos_and_ortho_cuts = []
+
+for f in projected_images:
+    name, _ = os.path.splitext(os.path.basename(f))
+    cutline_file = os.path.join(tmp_path, "%s_cutline.gpkg" % name)
+    bounds_file_path = os.path.join(tmp_path, "%s.gpkg" % name)
+    
+    compute_cutline(f, 
+                    bounds_file_path,
+                    cutline_file,
+                    4,
+                    scale=1)
+
+    cut_raster = os.path.join(tmp_path, "%s_cut.tif" % name)
+    orthophoto.compute_mask_raster(f, cutline_file, 
+                            cut_raster,
+                            blend_distance=20, only_max_coords_feature=True)
+
+    feathered_raster = os.path.join(tmp_path, "%s_feathered.tif" % name)
+
+    orthophoto.feather_raster(f, feathered_raster,
+                            blend_distance=20
+                        )
+
+    all_orthos_and_ortho_cuts.append([feathered_raster, cut_raster])
+
+log.ODM_INFO("Merging...")
+
+if len(all_orthos_and_ortho_cuts) > 1:
+    # TODO: histogram matching via rasterio
+    # currently parts have different color tones
+    output_file = os.path.join(cwd_path, 'mergepreview.tif')
+
+    if os.path.isfile(output_file):
+        os.remove(output_file)
+
+    orthophoto.merge(all_orthos_and_ortho_cuts, output_file, {
+        'TILED': 'YES',
+        'COMPRESS': 'LZW',
+        'PREDICTOR': '2',
+        'BIGTIFF': 'IF_SAFER',
+        'BLOCKXSIZE': 512,
+        'BLOCKYSIZE': 512
+    })
+
+
+    log.ODM_INFO("Wrote %s" % output_file)
+    shutil.rmtree(tmp_path)
+else:
+    log.ODM_ERROR("Error: no orthos found to merge")
+    exit(1)

opendm/cutline.py

@@ -145,9 +145,12 @@ def compute_cutline(orthophoto_file, crop_area_file, destination, max_concurrenc
         if len(polygons) == 0:
             log.ODM_WARNING("No polygons, cannot compute cutline")
             return
-        
+
         log.ODM_INFO("Merging polygons")
         cutline_polygons = unary_union(polygons)
+        if not hasattr(cutline_polygons, '__getitem__'):
+            cutline_polygons = [cutline_polygons]
+
         largest_cutline = cutline_polygons[0]
         max_area = largest_cutline.area
         for p in cutline_polygons: