genesys: Add model flag for inverted output

backend/genesys/enums.h

@@ -507,6 +507,9 @@ enum class ModelFlag : unsigned
     // the head must be reparked between shading scans
     SHADING_REPARK = 1 << 18,
 
+    // the scanner outputs inverted pixel data
+    INVERT_PIXEL_DATA = 1 << 19,
+
     // the scanner outputs 16-bit data that is byte-inverted
     SWAP_16BIT_DATA = 1 << 20,
 

backend/genesys/low.cpp

@@ -544,6 +544,10 @@ Image read_unshuffled_image_from_scanner(Genesys_Device* dev, const ScanSession&
         pipeline.push_node<ImagePipelineNodeSwap16BitEndian>();
     }
 
+    if (has_flag(dev->model->flags, ModelFlag::INVERT_PIXEL_DATA)) {
+        pipeline.push_node<ImagePipelineNodeInvert>();
+    }
+
 #ifdef WORDS_BIGENDIAN
     if (session.params.depth == 16) {
         pipeline.push_node<ImagePipelineNodeSwap16BitEndian>();
@@ -1192,6 +1196,10 @@ void build_image_pipeline(Genesys_Device* dev, const ScanSession& session)
                                                         "_1_after_swap.pnm");
     }
 
+    if (has_flag(dev->model->flags, ModelFlag::INVERT_PIXEL_DATA)) {
+        dev->pipeline.push_node<ImagePipelineNodeInvert>();
+    }
+
     if (dev->model->is_cis && session.params.channels == 3) {
         dev->pipeline.push_node<ImagePipelineNodeMergeMonoLines>(dev->model->line_mode_color_order);
     }