[nodes] ldrToHdr: automatic brackets estimation (temporary solution)

meshroom/nodes/aliceVision/LdrToHdrSampling.py

@@ -1,7 +1,27 @@
 __version__ = "2.0"
 
+import json
+import os
+
 from meshroom.core import desc
 
+def findMetadata(d, keys, defaultValue):
+    v = None
+    for key in keys:
+        v = d.get(key, None)
+        k = key.lower()
+        if v != None:
+            return v
+        for dk, dv in d.iteritems():
+            dkm = dk.lower().replace(" ", "")
+            if dkm == key.lower():
+                return dv
+            dkm = dkm.split(":")[-1]
+            dkm = dkm.split("/")[-1]
+            if dkm == k:
+                return dv
+    return defaultValue
+
 
 class LdrToHdrSampling(desc.CommandLineNode):
     commandLine = 'aliceVision_LdrToHdrSampling {allParams}'
@@ -74,4 +94,66 @@ class LdrToHdrSampling(desc.CommandLineNode):
             value=desc.Node.internalFolder,
             uid=[],
         ),
-    ]
+    ]
+
+    @classmethod
+    def update(cls, node):
+        if not isinstance(node.nodeDesc, cls):
+            raise ValueError("Node {} is not an instance of type {}".format(node, cls))
+        # TODO: use Node version for this test
+        if 'userNbBrackets' not in node.getAttributes().keys():
+            # Old version of the node
+            return
+        if node.userNbBrackets.value != 0:
+            node.nbBrackets.value = node.userNbBrackets.value
+            return
+        # logging.info("[LDRToHDR] Update start: version:" + str(node.packageVersion))
+        cameraInitOutput = node.input.getLinkParam()
+        if not cameraInitOutput:
+            node.nbBrackets.value = 0
+            return
+        viewpoints = cameraInitOutput.node.viewpoints.value
+
+        # logging.info("[LDRToHDR] Update start: nb viewpoints:" + str(len(viewpoints)))
+        inputs = []
+        for viewpoint in viewpoints:
+            jsonMetadata = viewpoint.metadata.value
+            if not jsonMetadata:
+                # no metadata, we cannot found the number of brackets
+                node.nbBrackets.value = 0
+                return
+            d = json.loads(jsonMetadata)
+            fnumber = findMetadata(d, ["FNumber", "Exif:ApertureValue", "ApertureValue", "Aperture"], "")
+            shutterSpeed = findMetadata(d, ["Exif:ShutterSpeedValue", "ShutterSpeedValue", "ShutterSpeed"], "")
+            iso = findMetadata(d, ["Exif:ISOSpeedRatings", "ISOSpeedRatings", "ISO"], "")
+            if not fnumber and not shutterSpeed:
+                # If one image without shutter or fnumber, we cannot found the number of brackets.
+                # We assume that there is no multi-bracketing, so nothing to do.
+                node.nbBrackets.value = 1
+                return
+            inputs.append((viewpoint.path.value, (fnumber, shutterSpeed, iso)))
+        inputs.sort()
+
+        exposureGroups = []
+        exposures = []
+        for path, exp in inputs:
+            if exposures and exp != exposures[-1] and exp == exposures[0]:
+                exposureGroups.append(exposures)
+                exposures = [exp]
+            else:
+                exposures.append(exp)
+        exposureGroups.append(exposures)
+        exposures = None
+        bracketSizes = set()
+        if len(exposureGroups) == 1:
+            node.nbBrackets.value = 1
+        else:
+            for expGroup in exposureGroups:
+                bracketSizes.add(len(expGroup))
+            if len(bracketSizes) == 1:
+                node.nbBrackets.value = bracketSizes.pop()
+                # logging.info("[LDRToHDR] nb bracket size:" + str(node.nbBrackets.value))
+            else:
+                node.nbBrackets.value = 0
+        # logging.info("[LDRToHDR] Update end")
+