Ensure getting true raw bytes for DR array

Author: BrianMichell

src/mdio/segy/_workers.py

@@ -9,6 +9,7 @@
 
 import numpy as np
 from segy import SegyFile
+from segy.indexing import merge_cat_file
 
 from mdio.api.io import to_mdio
 from mdio.builder.schemas.dtype import ScalarType
@@ -153,13 +154,39 @@ def trace_worker(  # noqa: PLR0913
         )
     if raw_header_key in worker_variables:
         tmp_raw_headers = np.zeros_like(dataset[raw_header_key])
-        tmp_raw_headers[not_null] = traces.header.view("|V240")  # TODO: Ensure this is using the RAW view and not an interpreted view.
+        
+        # Get the indices where we need to place results
+        live_mask = not_null
+        live_positions = np.where(live_mask.ravel())[0]
+        
+        if len(live_positions) > 0:
+            # Calculate byte ranges for headers
+            HEADER_SIZE = 240
+            trace_offset = segy_file.spec.trace.offset
+            trace_itemsize = segy_file.spec.trace.itemsize
+            
+            starts = []
+            ends = []
+            for global_trace_idx in live_trace_indexes:
+                header_start = trace_offset + global_trace_idx * trace_itemsize
+                header_end = header_start + HEADER_SIZE
+                starts.append(header_start)
+                ends.append(header_end)
+            
+            # Capture raw bytes
+            raw_header_bytes = merge_cat_file(segy_file.fs, segy_file.url, starts, ends)
+            
+            # Convert and place results
+            raw_headers_array = np.frombuffer(bytes(raw_header_bytes), dtype="|V240")
+            tmp_raw_headers.ravel()[live_positions] = raw_headers_array
+        
         ds_to_write[raw_header_key] = Variable(
             ds_to_write[raw_header_key].dims,
             tmp_raw_headers,
             attrs=ds_to_write[raw_header_key].attrs,
-            encoding=ds_to_write[raw_header_key].encoding,  # Not strictly necessary, but safer than not doing it.
+            encoding=ds_to_write[raw_header_key].encoding,
         )
+    
     data_variable = ds_to_write[data_variable_name]
     fill_value = _get_fill_value(ScalarType(data_variable.dtype.name))
     tmp_samples = np.full_like(data_variable, fill_value=fill_value)