diff --git a/core-buffer/include/WriterH5Writer.hpp b/core-buffer/include/WriterH5Writer.hpp
index dae7b39..822a7f1 100644
--- a/core-buffer/include/WriterH5Writer.hpp
+++ b/core-buffer/include/WriterH5Writer.hpp
@@ -13,6 +13,7 @@ struct ImageMetadata
     uint32_t daq_rec;
     uint16_t n_received_packets;
     bool is_good_frame;
+    uint64_t compressed_image_size;
 };
 
 class WriterH5Writer {