diff --git a/sf-buffer/sf_buffer.cpp b/sf-buffer/sf_buffer.cpp
deleted file mode 100644
index 8cbf20b..0000000
--- a/sf-buffer/sf_buffer.cpp
+++ /dev/null
@@ -1,99 +0,0 @@
-#include <iostream>
-#include <stdexcept>
-#include <RingBuffer.hpp>
-#include <sys/socket.h>
-#include <netinet/in.h>
-#include <UdpReceiver.hpp>
-#include <UdpRecvModule.hpp>
-#include <H5Writer.hpp>
-
-#include "config.hpp"
-#include "jungfrau.hpp"
-
-
-using namespace std;
-
-int main (int argc, char *argv[]) {
-    if (argc != 6) {
-        cout << endl;
-        cout << "Usage: sf_buffer [device_name] [udp_port] [root_folder]";
-        cout << endl;
-        cout << "\tdevice_name: Name to write to disk.";
-        cout << "\tudp_port: UDP port to connect to." << endl;
-        cout << "\troot_folder: FS root folder." << endl;
-        cout << endl;
-
-        exit(-1);
-    }
-
-    string device_name = string(argv[1]);
-    int udp_port = atoi(argv[2]);
-    string root_folder = string(argv[3]);
-
-    RingBuffer<UdpFrameMetadata> ring_buffer(config::ring_buffer_n_slots);
-
-    UdpRecvModule udp_module(ring_buffer);
-    udp_module.start_recv(udp_port, JUNGFRAU_DATA_BYTES_PER_FRAME);
-
-    H5Writer writer("output.h5");
-    writer.create_file();
-
-    while (true) {
-        auto data = ring_buffer.read();
-
-        if (data.first == nullptr) {
-            this_thread::sleep_for(chrono::milliseconds(10));
-            continue;
-        }
-
-        auto pulse_id = data.first->pulse_id;
-        // TODO: Make this modulo of pulse_id.
-        auto file_frame_index = 0;
-
-        writer.write_data(
-                "pulse_id",
-                file_frame_index,
-                (char*)(&data.first->pulse_id),
-                {1},
-                8,
-                "uint64",
-                "little");
-
-        writer.write_data(
-                "frame_id",
-                file_frame_index,
-                (char*)(&data.first->frame_index),
-                {1},
-                8,
-                "uint64",
-                "little");
-
-        writer.write_data(
-                "daq_rec",
-                file_frame_index,
-                (char*)(&data.first->daq_rec),
-                {1},
-                8,
-                "uint32",
-                "little");
-
-        writer.write_data(
-                "recv_packets_1",
-                file_frame_index,
-                (char*)(&data.first->recv_packets_1),
-                {1},
-                8,
-                "uint64",
-                "little");
-
-        writer.write_data(
-                "recv_packets_2",
-                file_frame_index,
-                (char*)(&data.first->recv_packets_2),
-                {1},
-                8,
-                "uint64",
-                "little");
-
-    }
-}
diff --git a/sf-buffer/src/sf_buffer.cpp b/sf-buffer/src/sf_buffer.cpp
new file mode 100644
index 0000000..d84b468
--- /dev/null
+++ b/sf-buffer/src/sf_buffer.cpp
@@ -0,0 +1,94 @@
+#include <iostream>
+#include <stdexcept>
+#include <RingBuffer.hpp>
+#include <UdpRecvModule.hpp>
+#include <H5Writer.hpp>
+
+#include "config.hpp"
+#include "jungfrau.hpp"
+#include "buffer_utils.hpp"
+
+
+using namespace std;
+
+
+int main (int argc, char *argv[]) {
+    if (argc != 6) {
+        cout << endl;
+        cout << "Usage: sf_buffer [device_name] [udp_port] [root_folder]";
+        cout << endl;
+        cout << "\tdevice_name: Name to write to disk.";
+        cout << "\tudp_port: UDP port to connect to." << endl;
+        cout << "\troot_folder: FS root folder." << endl;
+        cout << endl;
+
+        exit(-1);
+    }
+
+    string device_name = string(argv[1]);
+    int udp_port = atoi(argv[2]);
+    string root_folder = string(argv[3]);
+
+    RingBuffer<UdpFrameMetadata> ring_buffer(config::ring_buffer_n_slots);
+
+    UdpRecvModule udp_module(ring_buffer);
+    udp_module.start_recv(udp_port, JUNGFRAU_DATA_BYTES_PER_FRAME);
+
+    string current_file;
+    H5Writer writer("");
+
+    while (true) {
+        auto data = ring_buffer.read();
+
+        if (data.first == nullptr) {
+            this_thread::sleep_for(chrono::milliseconds(10));
+            continue;
+        }
+
+        auto pulse_id = data.first->pulse_id;
+
+        auto frame_file = get_filename(
+                root_folder,
+                device_name,
+                pulse_id);
+
+        if (current_file != frame_file) {
+            writer.close_file();
+            writer.create_file(frame_file);
+            current_file = frame_file;
+        }
+
+        auto file_frame_index = get_file_frame_index(pulse_id);
+
+        writer.write_data(
+                "image", file_frame_index,
+                data.second, {512,1024}, 2, "uint16", "little");
+
+        writer.write_data(
+                "pulse_id", file_frame_index,
+                (char*)(&data.first->pulse_id), {1}, 8,
+                "uint64", "little");
+
+        writer.write_data(
+                "frame_id", file_frame_index,
+                (char*)(&data.first->frame_index), {1}, 8,
+                "uint64", "little");
+
+        writer.write_data(
+                "daq_rec", file_frame_index,
+                (char*)(&data.first->daq_rec), {1}, 8,
+                "uint32", "little");
+
+        writer.write_data(
+                "recv_packets_1", file_frame_index,
+                (char*)(&data.first->recv_packets_1), {1}, 8,
+                "uint64", "little");
+
+        writer.write_data(
+                "recv_packets_2", file_frame_index,
+                (char*)(&data.first->recv_packets_2), {1}, 8,
+                "uint64", "little");
+
+        ring_buffer.reserve(data.first);
+    }
+}