diff --git a/src/common/defs.cpp b/src/common/defs.cpp
index 81e4065..08e9f70 100644
--- a/src/common/defs.cpp
+++ b/src/common/defs.cpp
@@ -1,5 +1,21 @@
 #include "defs.hpp"
 
+template <> std::string toString(DetectorType type) {
+    switch (type) {
+    case DetectorType::Jungfrau:
+        return "Jungfrau";
+    case DetectorType::Eiger:
+        return "Eiger";
+    case DetectorType::Mythen3:
+        return "Mythen3";
+    case DetectorType::Moench:
+        return "Moench";
+    default:
+        return "Unknown";
+    }
+}
+
+
  template <> DetectorType StringTo(std::string name) {
     if (name == "Jungfrau")
         return DetectorType::Jungfrau;
diff --git a/src/common/defs.hpp b/src/common/defs.hpp
index 826fb80..230452e 100644
--- a/src/common/defs.hpp
+++ b/src/common/defs.hpp
@@ -42,7 +42,14 @@ T StringTo(std::string sv){
     return T(sv);
 }
 
+template<class T> 
+std::string toString(T sv){
+    return T(sv);
+}
+
 template <> DetectorType StringTo(std::string);
+template <> std::string toString(DetectorType type);
+
 
 template <> TimingMode StringTo(std::string);
 
diff --git a/src/core/Frame.cpp b/src/core/Frame.cpp
index dde8271..d2ca577 100644
--- a/src/core/Frame.cpp
+++ b/src/core/Frame.cpp
@@ -1,22 +1,23 @@
 #include "Frame.hpp"
 #include <iostream>
 
+template <typename DataType>
+Frame<DataType>::Frame(std::byte* bytes, ssize_t rows, ssize_t cols):
+  rows(rows), cols(cols) {
+    data = new DataType[rows*cols];
+    std::memcpy(data, bytes, rows*cols*sizeof(DataType));
+  }
 
-FrameImpl::FrameImpl(std::byte* bytes, ssize_t rows, ssize_t cols, ssize_t bitdepth)
- {
-  this->rows = rows;
-  this->cols = cols;
-  data = new std::byte[rows * cols*bitdepth/8];
-  std::memcpy(data, bytes, bitdepth/8 * rows * cols);
-}
 
-std::byte* FrameImpl::get(int row, int col) {
+
+template <typename DataType>
+DataType Frame<DataType>::get(int row, int col) {
   if (row < 0 || row >= rows || col < 0 || col >= cols) {
     std::cerr << "Invalid row or column index" << std::endl;
     return 0;
   }
-  return  data+(row * cols + col)*bitdepth/8;
-
-
+  return data[row*cols + col];
 }
 
+
+template class Frame<uint16_t>;
diff --git a/src/core/Frame.hpp b/src/core/Frame.hpp
index cbd65b2..1aeef3e 100644
--- a/src/core/Frame.hpp
+++ b/src/core/Frame.hpp
@@ -13,25 +13,21 @@
  * model class
  * should be able to work with streams coming from files or network
 */
-class FrameImpl {
-    protected:
-    std::byte* data{nullptr};
-    ssize_t rows{};
-    ssize_t cols{};
-    ssize_t bitdepth{};
-    public:
-    FrameImpl(std::byte* fp, ssize_t rows, ssize_t cols, ssize_t bitdepth);
-    std::byte* get(int row, int col);
-    ~FrameImpl(){
-        delete[] data;
-    }
-};
 
-template <class DataType> class Frame: public FrameImpl {
+
+template <class DataType> class Frame{
+
     public:
-    Frame(std::byte* fp, ssize_t rows, ssize_t cols):FrameImpl(fp, rows, cols, sizeof(DataType)){}
-    DataType get(int row, int col){
-        return *((DataType*) FrameImpl::get(row, col));
+    ssize_t rows;
+    ssize_t cols;
+    DataType* data;
+    ssize_t bitdepth = sizeof(DataType)*8;
+
+    Frame(std::byte* fp, ssize_t rows, ssize_t cols);
+    DataType get(int row, int col);
+
+    ~Frame(){
+        delete[] data;
     }
 
 };
diff --git a/src/file_io/file/File.cpp b/src/file_io/file/File.cpp
index 944e477..3bcbba0 100644
--- a/src/file_io/file/File.cpp
+++ b/src/file_io/file/File.cpp
@@ -1,7 +1,9 @@
 #include "File.hpp"
-
-File::~File() {
+template <DetectorType detector, typename DataType>
+File<detector,DataType>::~File<detector,DataType>() {
     for (auto& subfile : subfiles) {
         delete subfile;
     }
 }
+
+template class File<DetectorType::Jungfrau, uint16_t>;
diff --git a/src/file_io/file/File.hpp b/src/file_io/file/File.hpp
index cdae0d6..42cd5d2 100644
--- a/src/file_io/file/File.hpp
+++ b/src/file_io/file/File.hpp
@@ -19,11 +19,11 @@ struct RawFileConfig {
         return true;
     }
 };
-
+template <DetectorType detector, typename DataType>
 class File {
 
   public:
-    virtual FrameImpl* get_frame(int frame_number) = 0;
+    virtual Frame<DataType>* get_frame(int frame_number) = 0;
 
   private:
     using config = RawFileConfig;
diff --git a/src/file_io/file/FileHandler.hpp b/src/file_io/file/FileHandler.hpp
index a5cd74d..43be842 100644
--- a/src/file_io/file/FileHandler.hpp
+++ b/src/file_io/file/FileHandler.hpp
@@ -1,24 +1,23 @@
 #include <filesystem>
 #include "FileFactory.hpp"
 #include "File.hpp"
+template <DetectorType detector,typename DataType>
 class FileHandler{
     private:
     std::filesystem::path fpath;
-    FileFactory* fileFactory;
-    File* f;
+    FileFactory<detector,DataType>* fileFactory;
+    File<detector,DataType>* f;
 
     public:
-    FileHandler(std::filesystem::path fpath){
+    FileHandler<detector,DataType>(std::filesystem::path fpath){
         this->fpath = fpath;
-         this->fileFactory= FileFactory::get_factory(fpath);
+         this->fileFactory= FileFactory<detector,DataType>::get_factory(fpath);
          this->f= fileFactory->load_file();
          delete fileFactory;
     }
 
-    template <typename DataType>
     Frame<DataType>* get_frame(int index){
-         FrameImpl* frame =f->get_frame(index);
-         return  static_cast<Frame<DataType>*>(frame);
+         return  f->get_frame(index);
     }
 
     
diff --git a/src/file_io/file/JsonFile.cpp b/src/file_io/file/JsonFile.cpp
index c6c424f..64602b2 100644
--- a/src/file_io/file/JsonFile.cpp
+++ b/src/file_io/file/JsonFile.cpp
@@ -1,17 +1,18 @@
 #include "JsonFile.hpp"
 #include <typeinfo>
 
-FrameImpl* JsonFile::get_frame(int frame_number){
-    int subfile_id=frame_number/max_frames_per_file;
+template <DetectorType detector,typename DataType>
+Frame<DataType>* JsonFile<detector,DataType>::get_frame(int frame_number){
+    int subfile_id=frame_number/this->max_frames_per_file;
     std::byte* buffer;
-    size_t frame_size = subfiles[subfile_id]->bytes_per_frame();
+    size_t frame_size = this->subfiles[subfile_id]->bytes_per_frame();
     buffer = new std::byte[frame_size];
 
-    subfiles[subfile_id]->get_frame(buffer, frame_number%max_frames_per_file);
+    this->subfiles[subfile_id]->get_frame(buffer, frame_number%this->max_frames_per_file);
 
 
 
-    auto f = new FrameImpl(buffer, rows, cols, bitdepth);
+    auto f = new Frame<DataType>(buffer, this->rows, this->cols);
 
     delete[] buffer;
     return f;
@@ -20,4 +21,7 @@ FrameImpl* JsonFile::get_frame(int frame_number){
 
 
 
-}
\ No newline at end of file
+}
+
+template class JsonFile<DetectorType::Jungfrau, uint16_t>;
+
diff --git a/src/file_io/file/JsonFile.hpp b/src/file_io/file/JsonFile.hpp
index 40b8440..a5285c4 100644
--- a/src/file_io/file/JsonFile.hpp
+++ b/src/file_io/file/JsonFile.hpp
@@ -1,11 +1,9 @@
 #pragma once
+#include "File.hpp"
 #include "Frame.hpp"
 #include "defs.hpp"
-#include "File.hpp"
+template <DetectorType detector, typename DataType>
+class JsonFile : public File<detector, DataType> {
 
-class JsonFile: public File
-{
-
-    FrameImpl* get_frame(int frame_number);
-    
+    Frame<DataType> *get_frame(int frame_number);
 };
\ No newline at end of file
diff --git a/src/file_io/file_factory/FileFactory.cpp b/src/file_io/file_factory/FileFactory.cpp
index 750b75b..51018ab 100644
--- a/src/file_io/file_factory/FileFactory.cpp
+++ b/src/file_io/file_factory/FileFactory.cpp
@@ -1,35 +1,34 @@
 #include "FileFactory.hpp"
 #include "File.hpp"
-#include "RawFileFactory.hpp"
 #include "JsonFileFactory.hpp"
+#include "RawFileFactory.hpp"
 #include <iostream>
 
-
-
- FileFactory* FileFactory::get_factory(std::filesystem::path fpath, uint16_t bitdepth){
+template <DetectorType detector, typename DataType>
+FileFactory<detector, DataType> *FileFactory<detector, DataType>::get_factory(std::filesystem::path fpath) {
     // check if file exists
-    if(!std::filesystem::exists(fpath)){
+    if (!std::filesystem::exists(fpath)) {
         throw std::runtime_error("File does not exist");
     }
 
-    if(fpath.extension() == ".raw"){
-        std::cout<<"Loading raw file"<<std::endl;
+    if (fpath.extension() == ".raw") {
+        std::cout << "Loading raw file" << std::endl;
         throw std::runtime_error("Raw file not implemented");
+    } else if (fpath.extension() == ".json") {
+        std::cout << "Loading json file" << std::endl;
+        return new JsonFileFactory<detector, DataType>(fpath);
     }
-    else if(fpath.extension() == ".json"){
-        std::cout<<"Loading json file"<<std::endl;
-        return new JsonFileFactory(fpath, bitdepth);
-    }
-    //check if extension is numpy
-    else if(fpath.extension() == ".npy"){
-        std::cout<<"Loading numpy file"<<std::endl;
+    // check if extension is numpy
+    else if (fpath.extension() == ".npy") {
+        std::cout << "Loading numpy file" << std::endl;
         throw std::runtime_error("Numpy file not implemented");
     }
-    
-    throw std::runtime_error("Unsupported file type");    
+
+    throw std::runtime_error("Unsupported file type");
 }
 
-void FileFactory::parse_fname(File* file) {
+template <DetectorType detector, typename DataType>
+void FileFactory<detector, DataType>::parse_fname(File<detector, DataType> *file) {
     file->base_path = fpath.parent_path();
     file->base_name = fpath.stem();
     file->ext = fpath.extension();
@@ -40,23 +39,22 @@ void FileFactory::parse_fname(File* file) {
     file->base_name.erase(pos);
 }
 
-template <typename Header=sls_detector_header>
- Header FileFactory::read_header(const std::filesystem::path &fname) {
-    Header h{};
+template <DetectorType detector, typename DataType>
+sls_detector_header FileFactory<detector, DataType>::read_header(const std::filesystem::path &fname) {
+    sls_detector_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()));
+        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) {
+template <DetectorType detector, typename DataType>
+void FileFactory<detector, DataType>::find_geometry(File<detector, DataType> *file) {
     uint16_t r{};
     uint16_t c{};
     for (int i = 0; i != file->n_subfiles; ++i) {
@@ -73,4 +71,6 @@ void FileFactory::find_geometry(File* file) {
     file->cols = c * file->subfile_cols;
 
     file->rows += (r - 1) * file->cfg.module_gap_row;
-}
\ No newline at end of file
+}
+
+template class FileFactory<DetectorType::Jungfrau, uint16_t>;
diff --git a/src/file_io/file_factory/FileFactory.hpp b/src/file_io/file_factory/FileFactory.hpp
index 65ad3e5..0826c2a 100644
--- a/src/file_io/file_factory/FileFactory.hpp
+++ b/src/file_io/file_factory/FileFactory.hpp
@@ -1,25 +1,25 @@
 #pragma once
 #include <filesystem>
 #include "File.hpp"
-
+template <DetectorType detector,typename DataType>
 class FileFactory{
     // Class that will be used to create File objects
     // follows the factory pattern
     protected:
     std::filesystem::path fpath;
-    uint16_t bitdepth;
 public:
-    static FileFactory* get_factory(std::filesystem::path,uint16_t bitdepth=16);
+    static FileFactory<detector,DataType>* get_factory(std::filesystem::path);
     // virtual int deleteFile() = 0;
-    virtual File* load_file()=0;//TODO: add option to load all file to memory or keep it on disk
-    virtual void parse_metadata(File*)=0;
+    virtual File<detector,DataType>* load_file()=0;//TODO: add option to load all file to memory or keep it on disk
+    virtual void parse_metadata(File<detector,DataType>*)=0;
     
     
-    void find_geometry(File*);
-    void parse_fname(File*);
+    void find_geometry(File<detector,DataType>*);
+    void parse_fname(File<detector,DataType>*);
 
-    template <typename Header> Header read_header(const std::filesystem::path &fname);
+    sls_detector_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 00be1f7..ce4a1b7 100644
--- a/src/file_io/file_factory/JsonFileFactory.cpp
+++ b/src/file_io/file_factory/JsonFileFactory.cpp
@@ -9,14 +9,15 @@
 
 using json = nlohmann::json;
 
-JsonFileFactory::JsonFileFactory(std::filesystem::path fpath, uint16_t bitdepth=16) {
+template <DetectorType detector,typename DataType>
+JsonFileFactory<detector,DataType>::JsonFileFactory(std::filesystem::path fpath) {
     if (not is_master_file(fpath))
         throw std::runtime_error("Json file is not a master file");
     this->fpath = fpath;
-    this->bitdepth = bitdepth;
 }
 
-void JsonFileFactory::parse_metadata(File *file) {
+template <DetectorType detector,typename DataType>
+void JsonFileFactory<detector,DataType>::parse_metadata(File<detector,DataType> *file) {
     std::cout << "Parsing metadata" << std::endl;
     std::ifstream ifs(file->master_fname());
     json j;
@@ -25,6 +26,9 @@ void JsonFileFactory::parse_metadata(File *file) {
     std::cout << "Version: " << v << std::endl;
     file->version = fmt::format("{:.1f}", v);
     file->type = StringTo<DetectorType>(j["Detector Type"].get<std::string>());
+    if (file->type != detector)
+        throw std::runtime_error("Detector type mismatch: file type (" + toString<DetectorType>(file->type) +
+                                 ") != specified type (" + toString<DetectorType>(detector) + ")");
     file->timing_mode = StringTo<TimingMode>(j["Timing Mode"].get<std::string>());
     file->total_frames = j["Frames in File"];
     file->subfile_cols = j["Pixels"]["x"];
@@ -36,9 +40,9 @@ void JsonFileFactory::parse_metadata(File *file) {
         std::cerr << "master file does not have Dynamic Range. Defaulting to 16 bit" << '\n';
         file->bitdepth = 16;
     }
-    // if (file->bitdepth != this->bitdepth)
-    //     throw std::runtime_error("Bitdepth mismatch: file bitdepth (" + std::to_string(file->bitdepth) +
-    //                              ") != specified bitdepth (" + std::to_string(this->bitdepth) + ")");
+    if (file->bitdepth != sizeof(DataType) * 8)
+        throw std::runtime_error("Bitdepth mismatch: file bitdepth (" + std::to_string(file->bitdepth) +
+                                 ") != specified bitdepth (" + std::to_string(sizeof(DataType) * 8) + ")");
 
     // only Eiger had quad
     if (file->type == DetectorType::Eiger) {
@@ -46,7 +50,8 @@ void JsonFileFactory::parse_metadata(File *file) {
     }
 }
 
-void JsonFileFactory::open_subfiles(File *file) {
+template <DetectorType detector,typename DataType>
+void JsonFileFactory<detector,DataType>::open_subfiles(File<detector,DataType> *file) {
     for (int i = 0; i != file->n_subfiles; ++i) {
 
         file->subfiles.push_back(
@@ -54,10 +59,11 @@ void JsonFileFactory::open_subfiles(File *file) {
     }
 }
 
-File *JsonFileFactory::load_file() {
+template <DetectorType detector,typename DataType>
+File<detector,DataType> *JsonFileFactory<detector,DataType>::load_file() {
     std::cout << "Loading json file" << std::endl;
-    JsonFile *file = new JsonFile();
-    file->fname = fpath;
+    JsonFile<detector,DataType> *file = new JsonFile<detector,DataType>();
+    file->fname = this->fpath;
     this->parse_fname(file);
     this->parse_metadata(file);
     file->find_number_of_subfiles();
@@ -65,4 +71,6 @@ File *JsonFileFactory::load_file() {
     this->open_subfiles(file);
 
     return file;
-}
\ No newline at end of file
+}
+
+template class JsonFileFactory<DetectorType::Jungfrau, uint16_t>;
\ No newline at end of file
diff --git a/src/file_io/file_factory/JsonFileFactory.hpp b/src/file_io/file_factory/JsonFileFactory.hpp
index c9bd947..b178a80 100644
--- a/src/file_io/file_factory/JsonFileFactory.hpp
+++ b/src/file_io/file_factory/JsonFileFactory.hpp
@@ -1,14 +1,14 @@
 #include "FileFactory.hpp"
-
-class JsonFileFactory: public FileFactory
+template <DetectorType detector,typename DataType>
+class JsonFileFactory: public FileFactory<detector,DataType>
 {
 private:
     /* data */
 public:
-    File* load_file() override;
-    void parse_metadata(File*) override;
-    JsonFileFactory(std::filesystem::path fpath, uint16_t bitdepth);
-    void open_subfiles(File*);
+    File<detector,DataType>* load_file() override;
+    void parse_metadata(File<detector,DataType>*) override;
+    JsonFileFactory<detector,DataType>(std::filesystem::path fpath);
+    void open_subfiles(File<detector,DataType>*);
     
 
 
diff --git a/src/file_io/file_factory/RawFileFactory.hpp b/src/file_io/file_factory/RawFileFactory.hpp
index 2c0ca8c..89ee537 100644
--- a/src/file_io/file_factory/RawFileFactory.hpp
+++ b/src/file_io/file_factory/RawFileFactory.hpp
@@ -1,9 +1,9 @@
 #include "File.hpp"
 #include <filesystem>
-
+template<DetectorType detector,typename DataType>  
 class RawFileFactory{
     public:
         // RawFileFactory();
         // ~RawFileFactory();
-        File loadFile(std::filesystem::path fpath);
+        File<detector,DataType> loadFile(std::filesystem::path fpath);
 };
\ No newline at end of file
diff --git a/src/main.cpp b/src/main.cpp
index d6b4f90..7ca38f8 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,9 +1,15 @@
 // Your First C++ Program
 #include <iostream>
 #include <FileHandler.hpp>
-void test(FileHandler* f,int frame_number){
+
+using JFileHandler = FileHandler<DetectorType::Jungfrau,uint16_t>;
+using JFile = File<DetectorType::Jungfrau,uint16_t>;
+using JFrame = Frame<uint16_t>;
+
+
+void test(JFileHandler* f,int frame_number){
     std::cout << "frame number: " << frame_number << std::endl;
-    Frame16* frame = f->get_frame<uint16_t>(frame_number);
+    JFrame* frame = f->get_frame(frame_number);
     std::cout << frame->get(0,0) << ' ';
     std::cout << frame->get(0,1) << ' ';
     std::cout << frame->get(1,0) << ' ';
@@ -14,8 +20,7 @@ void test(FileHandler* f,int frame_number){
 
 int main() {
     std::filesystem::path fpath("/home/l_bechir/github/aare/data/jungfrau_single_master_0.json");
-    FileHandler* fileHandler = new FileHandler(fpath);
-    test(fileHandler,0);
+    auto fileHandler = new JFileHandler (fpath);
 
     delete fileHandler;