diff --git a/CHANGELOG.md b/CHANGELOG.md
index 89810e3..52f3303 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,9 @@ Activate / deactivate layer opaticty according to prefix
 Activate / deactivate all masks using MA layers
 -->
 
+0.9.3
+
+- feat: export a json with layers info for compo. Masks, opacity, blend mode
 
 0.9.2
 
diff --git a/OP_setup_layers.py b/OP_setup_layers.py
index 1922463..23d3a59 100644
--- a/OP_setup_layers.py
+++ b/OP_setup_layers.py
@@ -7,9 +7,138 @@ from bpy.props import (FloatProperty,
 from . import fn
 import math
 import re
+import json
+from pathlib import Path
 
 ## TODO : export json info to re-setup layers in AE automagically
 
+def check_outname(ob, l):
+    vl_name = l.viewlayer_render
+    if vl_name in {'exclude', 'View Layer'}:
+        return
+
+    ng_name = f'NG_{ob.name}'
+    ## check in wich node tree this exists
+    for scn in bpy.data.scenes:
+        if scn.name == 'Scene':
+            continue
+        ng = scn.node_tree.nodes.get(ng_name)
+        if ng:
+            break
+    print(scn.name)
+    if not ng:
+        print(f'Skip {vl_name}: Not found nodegroup {ng_name}' )
+        return
+    ng_socket = ng.outputs.get(vl_name)
+    if not ng_socket:
+        print(f'Skip {vl_name}: Not found in nodegroup {ng_name} sockets')
+        return
+    if not len(ng_socket.links):
+        print(f' socket is disconnected in {ng_name} nodegroup')
+        return
+    fo_node = ng_socket.links[0].to_node
+    fo_socket = ng_socket.links[0].to_socket
+    if fo_node.type != 'OUTPUT_FILE':
+        print(f'Skip {vl_name}: node is not an output_file {fo_node.name}')
+        return
+    
+    # fo_socket.name isn't right, have to iterate in paths
+    idx = [i for i in fo_node.inputs].index(fo_socket)
+    subpath = fo_node.file_slots[idx].path
+    # fp = Path(fo_node.base_path.rstrip('/')) / subpath
+    # fp = Path(bpy.path.abspath(str(fp)).rstrip("/")) # abspath on disk
+    outname = subpath.split('/')[0] # folder name on disk
+    
+    return outname
+
+class GPEXP_OT_export_infos_for_compo(bpy.types.Operator):
+    bl_idname = "gp.export_infos_for_compo"
+    bl_label = "Export Infos For Compo"
+    bl_description = "Export informations for compositing, including layers with masks, fusion mode, opacity"
+    bl_options = {"REGISTER", "UNDO"}
+
+    @classmethod
+    def poll(cls, context):
+        return context.object and context.object.type == 'GPENCIL'
+
+    def invoke(self, context, event):
+
+        self.l_infos = Path(bpy.data.filepath).parent / 'render' / 'infos.json'
+        if self.l_infos.exists():
+            return context.window_manager.invoke_props_dialog(self)
+        return self.execute(context)
+
+    def draw(self, context):
+        layout = self.layout
+        layout.label(text='An infos Json already exists', icon = 'ERROR')
+        layout.label(text='Do you want to overwrite ?')
+        layout.label(text='Note: Must export before "Check Layers" step', icon='INFO')
+
+    def execute(self, context):
+        dic = {}
+        pool = [o for o in context.scene.objects if o.type == 'GPENCIL']
+        for o in pool:
+            # if not o.visible_get():
+            #     continue
+            for l in o.data.layers:
+                # skip non rendered layers
+                if l.hide:
+                    continue
+                
+                if l.info.startswith('MA_'):
+                    # No point in storing information of masking layers...
+                    continue
+
+                ## Can't check viewlayers and final fileout name if Render scene not even created...
+                """ if not l.viewlayer_render or l.viewlayer_render == 'exclude':
+                    continue
+                
+                fo_name = check_outname(o, l) # get name used for output file folder (same in AE)
+                if not fo_name:
+                    print(f'! Could not found fileout name for {o.name} > {l.info}')
+                    continue
+                """
+
+                ldic = {}
+                ## Check opacity, blend mode
+                if l.opacity < 1.0:
+                    ldic['opacity'] = l.opacity
+                
+                if l.blend_mode != 'REGULAR':
+                    ldic['blend_mode'] = l.blend_mode
+
+                if l.use_mask_layer:
+
+                    multi_mask = {}
+                    for i, ml in enumerate(l.mask_layers):
+                        mask = {}
+                        if ml.hide:
+                            continue
+                        mask['name'] = ml.name
+                        if ml.invert: # create key get only if inverted
+                            mask['invert'] = ml.invert
+                        # multi_mask[ml.name] = mask
+                        multi_mask[i] = mask
+
+                    if multi_mask:
+                        ldic['masks'] = multi_mask
+                
+                ## add to full dic
+                if ldic:
+                    # add source object ? might be usefull to pin point layer
+                    ldic['object'] = o.name
+                    dic[fn.normalize_layer_name(l, get_only=True)] = ldic
+
+        if dic:
+            with self.l_infos.open('w') as fd:
+                json.dump(dic, fd, indent='\t')
+            self.report({'INFO'}, f'Exported json at: {self.l_infos.as_posix()}')
+        else:
+            self.report({'WARNING'}, f'No custom data to write with those objects/layers')
+            return {"CANCELLED"}
+
+        return {"FINISHED"}
+
 class GPEXP_OT_layers_state(bpy.types.Operator):
     bl_idname = "gp.layers_state"
     bl_label = "Set Layers State"
@@ -380,9 +509,10 @@ class GPEXP_OT_check_masks(bpy.types.Operator):
         return {"FINISHED"}
 
 classes=(
-GPEXP_OT_layers_state,
-GPEXP_OT_lower_layers_name,
 GPEXP_OT_auto_number_object,
+GPEXP_OT_lower_layers_name,
+GPEXP_OT_export_infos_for_compo,
+GPEXP_OT_layers_state,
 GPEXP_OT_check_masks,
 )
 
diff --git a/__init__.py b/__init__.py
index f9a06cd..044c4cb 100644
--- a/__init__.py
+++ b/__init__.py
@@ -2,7 +2,7 @@ bl_info = {
     "name": "GP Render",
     "description": "Organise export of gp layers through compositor output",
     "author": "Samuel Bernou",
-    "version": (0, 9, 2),
+    "version": (0, 9, 3),
     "blender": (2, 93, 0),
     "location": "View3D",
     "warning": "",
diff --git a/fn.py b/fn.py
index 0f5d95f..267ba0e 100644
--- a/fn.py
+++ b/fn.py
@@ -728,7 +728,7 @@ def normalize(text):
     return text.lower().replace('-', '_')
 
 PATTERN = r'^(?P<grp>-\s)?(?P<tag>[A-Z]{2}_)?(?P<name>.*?)(?P<sfix>_[A-Z]{2})?(?P<inc>\.\d{3})?$' # numering
-def normalize_layer_name(layer, prefix='', desc='', suffix='', lower=True, dash_to_underscore=True):
+def normalize_layer_name(layer, prefix='', desc='', suffix='', lower=True, dash_to_underscore=True, get_only=False):
     '''GET a layer and argument to build and assign name'''
     import re
 
@@ -772,7 +772,8 @@ def normalize_layer_name(layer, prefix='', desc='', suffix='', lower=True, dash_
         name = name.replace('-', '_')
 
     new = f'{grp}{tag}{name}{sfix}' # lower suffix ?
-
+    if get_only:
+        return new
     if new != layer.info:
         old = layer.info
         print(f'{old} >> {new}')
diff --git a/ui.py b/ui.py
index d159972..63c0f9a 100644
--- a/ui.py
+++ b/ui.py
@@ -211,8 +211,9 @@ class GPEXP_PT_gp_dopesheet_ui(Panel):
         row = col.row(align=True)
         row.operator('gp.auto_number_object', icon='OBJECT_DATAMODE', text='Renumber Objects')
         row.operator('gp.auto_number_object', icon='X', text='').delete = True
-        col.operator('gp.layers_state', icon='CHECKMARK', text='Check layers')
         col.operator('gp.lower_layers_name', icon='SYNTAX_OFF', text='Rename Lowercase')
+        col.operator('gp.export_infos_for_compo', icon='FILE', text='Export Layers Infos')
+        col.operator('gp.layers_state', icon='CHECKMARK', text='Check layers')
         col.operator('gp.check_masks', icon='MOD_MASK', text='Has Masks')
         
         # row = layout.row()