diff --git a/.vscode/c_cpp_properties.json b/.vscode/c_cpp_properties.json
index 25015e2..10e21c5 100644
--- a/.vscode/c_cpp_properties.json
+++ b/.vscode/c_cpp_properties.json
@@ -3,14 +3,16 @@
         {
             "name": "Linux",
             "includePath": [
-                "${workspaceFolder}/**"
+                "${workspaceFolder}/**",
+                "/usr/include"
             ],
             "defines": [],
             "compilerPath": "/usr/bin/g++",
             "cStandard": "c17",
             "cppStandard": "c++17",
             "intelliSenseMode": "linux-gcc-x64",
-            "configurationProvider": "ms-vscode.cmake-tools"
+            "configurationProvider": "ms-vscode.cmake-tools",
+            "compilerArgs": []
         }
     ],
     "version": 4
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 98ac888..eb20097 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -9,6 +9,7 @@ project(aare
 
 cmake_policy(SET CMP0135 NEW)
 
+include(GNUInstallDirs)
 
 include(FetchContent)
 
diff --git a/src/common/CMakeLists.txt b/src/common/CMakeLists.txt
index ec461e6..84fba25 100644
--- a/src/common/CMakeLists.txt
+++ b/src/common/CMakeLists.txt
@@ -1,7 +1,5 @@
-target_include_directories(aare PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/include )
-
 target_include_directories(aare PUBLIC ${CMAKE_CURRENT_SOURCE_DIR})
 
-
+target_sources(aare PRIVATE  "${CMAKE_CURRENT_SOURCE_DIR}/defs.cpp")
 
 
diff --git a/src/common/defs.cpp b/src/common/defs.cpp
new file mode 100644
index 0000000..81e4065
--- /dev/null
+++ b/src/common/defs.cpp
@@ -0,0 +1,27 @@
+#include "defs.hpp"
+
+ template <> DetectorType StringTo(std::string name) {
+    if (name == "Jungfrau")
+        return DetectorType::Jungfrau;
+    else if (name == "Eiger")
+        return DetectorType::Eiger;
+    else if (name == "Mythen3")
+        return DetectorType::Mythen3;
+    else if (name == "Moench")
+        return DetectorType::Moench;
+    else {
+        auto msg = fmt::format("Could not decode dector from: \"{}\"", name);
+        throw std::runtime_error(msg);
+    }
+}
+
+template <> TimingMode StringTo(std::string mode){
+    if (mode == "auto")
+        return TimingMode::Auto;
+    else if(mode == "trigger")
+        return TimingMode::Trigger;
+    else{
+        auto msg = fmt::format("Could not decode timing mode from: \"{}\"", mode);
+        throw std::runtime_error(msg);
+    }
+}
\ No newline at end of file
diff --git a/src/common/defs.hpp b/src/common/defs.hpp
new file mode 100644
index 0000000..0025f24
--- /dev/null
+++ b/src/common/defs.hpp
@@ -0,0 +1,47 @@
+#pragma once
+
+#include <array>
+#include <vector>
+#include <sys/types.h>
+#include <string_view>
+#include <stdexcept>
+#include <fmt/format.h>
+
+typedef struct {
+    uint64_t frameNumber;
+    uint32_t expLength;
+    uint32_t packetNumber;
+    uint64_t bunchId;
+    uint64_t timestamp;
+    uint16_t modId;
+    uint16_t row;
+    uint16_t column;
+    uint16_t reserved;
+    uint32_t debug;
+    uint16_t roundRNumber;
+    uint8_t detType;
+    uint8_t version;
+    uint8_t packetMask[64];
+}__attribute__((packed)) sls_detector_header;
+
+struct xy {
+    int row;
+    int col;
+};
+
+using image_shape = std::array<ssize_t, 2>;
+using dynamic_shape = std::vector<ssize_t>;
+
+enum class DetectorType { Jungfrau, Eiger, Mythen3, Moench };
+
+enum class TimingMode {Auto, Trigger};
+
+template<class T> 
+T StringTo(std::string sv){
+    return T(sv);
+}
+
+template <> DetectorType StringTo(std::string);
+
+template <> TimingMode StringTo(std::string);
+
diff --git a/src/common/include/defs.hpp b/src/common/include/defs.hpp
deleted file mode 100644
index e782527..0000000
--- a/src/common/include/defs.hpp
+++ /dev/null
@@ -1,14 +0,0 @@
-#include <array>
-#include <vector>
-#include <sys/types.h>
-
-
-
-
-using image_shape = std::array<ssize_t, 2>;
-using dynamic_shape = std::vector<ssize_t>;
-
-enum class DetectorType { Jungfrau, Eiger, Mythen3, Moench };
-
-enum class TimingMode {Auto, Trigger};
-DetectorType StringTo(std::string_view name);
\ No newline at end of file
diff --git a/src/file_io/file/File.hpp b/src/file_io/file/File.hpp
index 9680348..ed101a5 100644
--- a/src/file_io/file/File.hpp
+++ b/src/file_io/file/File.hpp
@@ -7,6 +7,7 @@
 class File
 {
 public:
+std::filesystem::path fname;
     std::filesystem::path base_path;
     std::string base_name,ext;
     int findex, n_subfiles;
@@ -16,6 +17,7 @@ public:
     DetectorType type;
     TimingMode timing_mode;
     int subfile_rows, subfile_cols;
+    bool quad {false};
 
 
 
@@ -23,18 +25,31 @@ public:
     ssize_t rows{};
     ssize_t cols{};
     uint8_t bitdepth{};
-    DetectorType type{};
+    std::vector<xy> positions;
+
     // File();
     // ~File();
     
 
+
+
     inline size_t bytes_per_frame() const{
         return rows*cols*bitdepth/8;
-        
     }
     inline size_t pixels() const{
         return rows*cols;
     }
+
+    // TODO! Deal with fast quad and missing files
+    inline void find_number_of_subfiles() {
+        int n_mod = 0;
+        while (std::filesystem::exists(data_fname(n_mod, 0))) {
+            n_mod++;
+        }
+        n_subfiles = n_mod;
+    }
+
+
     inline std::filesystem::path master_fname() {
     return base_path / fmt::format("{}_master_{}{}", base_name, findex, ext);
     }
diff --git a/src/file_io/file_factory/FileFactory.cpp b/src/file_io/file_factory/FileFactory.cpp
index b323ec0..601108e 100644
--- a/src/file_io/file_factory/FileFactory.cpp
+++ b/src/file_io/file_factory/FileFactory.cpp
@@ -39,3 +39,38 @@ void FileFactory::parse_fname(File& file) {
     pos = file.base_name.find("_master_");
     file.base_name.erase(pos);
 }
+
+template <typename Header=sls_detector_header>
+ Header FileFactory::read_header(const std::filesystem::path &fname) {
+    Header h{};
+    FILE *fp = fopen(fname.c_str(), "r");
+    if (!fp)
+        throw std::runtime_error(
+            fmt::format("Could not open: {} for reading", fname.c_str()));
+
+    size_t rc = fread(reinterpret_cast<char *>(&h), sizeof(h), 1, fp);
+    fclose(fp);
+    if (rc != 1)
+        throw std::runtime_error("Could not read header from file");
+    return h;
+   
+}
+
+void FileFactory::find_geometry(File& file) {
+    uint16_t r{};
+    uint16_t c{};
+    for (int i = 0; i != file.n_subfiles; ++i) {
+        auto h = this->read_header(file.data_fname(i, 0));
+        r = std::max(r, h.row);
+        c = std::max(c, h.column);
+
+        file.positions.push_back({h.row, h.column});
+    }
+    r++;
+    c++;
+
+    file.rows = r * file.subfile_rows;
+    file.cols = c * file.subfile_cols;
+
+    file.rows += (r - 1) * cfg.module_gap_row;
+}
\ No newline at end of file
diff --git a/src/file_io/file_factory/FileFactory.hpp b/src/file_io/file_factory/FileFactory.hpp
index 247afd4..6bf251c 100644
--- a/src/file_io/file_factory/FileFactory.hpp
+++ b/src/file_io/file_factory/FileFactory.hpp
@@ -12,10 +12,13 @@ public:
     // virtual int deleteFile() = 0;
     virtual File loadFile(){};//TODO: add option to load all file to memory or keep it on disk
     virtual void parse_metadata(File&){};
-
-    // inline fs::path master_fname() const {
-    // return base_path / fmt::format("{}_master_{}{}", base_name, findex, ext);}
-
+    
+    
+    void find_geometry(File&){};
     void parse_fname(File&);
 
+    template <typename Header> Header read_header(const std::filesystem::path &fname);
+
+
+
 };
diff --git a/src/file_io/file_factory/JsonFileFactory.cpp b/src/file_io/file_factory/JsonFileFactory.cpp
index e62082f..9b46c99 100644
--- a/src/file_io/file_factory/JsonFileFactory.cpp
+++ b/src/file_io/file_factory/JsonFileFactory.cpp
@@ -3,13 +3,14 @@
 #include "helpers.hpp"
 #include <iostream>
 #include <fstream>
-
+#include "defs.hpp"
 #include <nlohmann/json.hpp>
 
 using json = nlohmann::json;
 
 
 
+
 JsonFileFactory::JsonFileFactory(std::filesystem::path fpath){
     if(not is_master_file(fpath))
         throw std::runtime_error("Json file is not a master file");
@@ -23,19 +24,21 @@ void JsonFileFactory::parse_metadata(File& file){
     ifs >> j;
     double v = j["Version"];
     file.version = fmt::format("{:.1f}", v);
-    file.type = StringTo<DetectorType>(j["Detector Type"].get<std::string>());
+    std::string tmp;
+    j["Detector Type"].get_to(tmp);
+    file.type = StringTo<DetectorType>(tmp);
     file.timing_mode = StringTo<TimingMode>(j["Timing Mode"].get<std::string>());
     file.total_frames = j["Frames in File"];
     file.subfile_cols = j["Pixels"]["x"];
     file.subfile_rows = j["Pixels"]["y"];
-    if (type_ == DetectorType::Moench)
-        bitdepth_ = 16;
+    if (file.type == DetectorType::Moench)
+        file.bitdepth = 16;
     else
-        bitdepth_ = j["Dynamic Range"];
+        file.bitdepth = j["Dynamic Range"];
 
     // only Eiger had quad
-    if (type_ == DetectorType::Eiger) {
-        quad_ = (j["Quad"] == 1);
+    if (file.type == DetectorType::Eiger) {
+        file.quad = (j["Quad"] == 1);
     }
 
 
@@ -46,8 +49,12 @@ void JsonFileFactory::parse_metadata(File& file){
 File JsonFileFactory::loadFile(){
     std::cout<<"Loading json file"<<std::endl;
     JsonFile file = JsonFile();
+    file.fname = fpath;
     this->parse_fname(file);
     this->parse_metadata(file);
+    file.find_number_of_subfiles();
+    this->find_geometry(file);
+    
 
 
 
diff --git a/src/file_io/file_factory/JsonFileFactory.hpp b/src/file_io/file_factory/JsonFileFactory.hpp
index 410db1c..42ef35d 100644
--- a/src/file_io/file_factory/JsonFileFactory.hpp
+++ b/src/file_io/file_factory/JsonFileFactory.hpp
@@ -9,5 +9,6 @@ public:
     void parse_metadata(File&) override;
     JsonFileFactory(std::filesystem::path fpath);
 
+
 };