diff --git a/src/net/image_pixels.cpp b/src/net/image_pixels.cpp
index 2b999dda..4be10975 100644
--- a/src/net/image_pixels.cpp
+++ b/src/net/image_pixels.cpp
@@ -24,7 +24,7 @@ namespace banggame {
         }
     }
     
-    image_pixels image_pixels::scale_to(uint32_t new_size) const {
+    image_pixels image_pixels::scale_to(uint32_t new_size) && {
         uint32_t new_width = width;
         uint32_t new_height = height;
 
@@ -41,11 +41,10 @@ namespace banggame {
         }
 
         if (new_width >= width && new_height >= height) {
-            return *this;
+            return std::move(*this);
         }
 
         image_pixels result { new_width, new_height };
-        result.pixels.resize(new_width * new_height * bytes_per_pixel);
         for (uint32_t y = 0; y < new_height; ++y) {
             for (uint32_t x = 0; x < new_width; ++x) {
                 uint32_t scaled_x = x * width / new_width;
@@ -119,8 +118,7 @@ namespace banggame {
         // Allocate memory for the image buffer
         image.format = PNG_FORMAT_RGBA;
 
-        image_pixels result{image.width, image.height};
-        result.pixels.resize(PNG_IMAGE_SIZE(image));
+        image_pixels result{ image.width, image.height };
         if (!png_image_finish_read(&image, nullptr, result.pixels.data(), 0, nullptr)) {
             png_image_free(&image);
             throw std::runtime_error("Failed to finish reading PNG image");
diff --git a/src/net/image_pixels.h b/src/net/image_pixels.h
index 582604f9..72474849 100644
--- a/src/net/image_pixels.h
+++ b/src/net/image_pixels.h
@@ -38,13 +38,18 @@ namespace banggame {
         constexpr bool operator == (const image_pixels_hash &other) const = default;
     };
 
-    struct image_pixels {
+    class image_pixels {
+    private:
         uint32_t width;
         uint32_t height;
         byte_vector pixels;
 
-        explicit operator bool () const {
-            return width != 0 && height != 0 && !pixels.empty();
+    public:
+        image_pixels() = default;
+        image_pixels(uint32_t width, uint32_t height)
+            : width{width}, height{height}
+        {
+            pixels.resize(width * height * bytes_per_pixel);
         }
 
         operator image_pixels_view() const {
@@ -54,7 +59,9 @@ namespace banggame {
         uint32_t get_pixel(uint32_t x, uint32_t y) const;
         void set_pixel(uint32_t x, uint32_t y, uint32_t value);
 
-        image_pixels scale_to(uint32_t new_size) const;
+        image_pixels scale_to(uint32_t new_size) &&;
+
+        friend image_pixels image_from_png_data_url(std::string_view data_url);
     };
 
     byte_vector image_to_png(image_pixels_view image);
diff --git a/src/net/lobby.cpp b/src/net/lobby.cpp
index 34729fb1..67b08d86 100644
--- a/src/net/lobby.cpp
+++ b/src/net/lobby.cpp
@@ -5,18 +5,18 @@
 
 namespace banggame {
 
-    void game_session::set_username(const std::string &new_username) {
+    void game_session::set_username(std::string new_username) {
         static constexpr size_t max_username_size = 50;
 
         if (new_username.size() > max_username_size) {
             username = new_username.substr(0, max_username_size);
         } else {
-            username = new_username;
+            username = std::move(new_username);
         }
     }
 
-    void game_session::set_propic(const image_pixels &new_propic) {
-        propic.reset(new_propic.scale_to(bot_info.propic_size));
+    void game_session::set_propic(image_pixels new_propic) {
+        propic.reset(std::move(new_propic).scale_to(bot_info.propic_size));
     }
 
     static auto find_user_it(auto &list, session_ptr session) {
diff --git a/src/net/lobby.h b/src/net/lobby.h
index 45018f8a..46f47688 100644
--- a/src/net/lobby.h
+++ b/src/net/lobby.h
@@ -38,8 +38,8 @@ struct game_session {
     client_handle client;
     ticks lifetime = user_lifetime;
 
-    void set_username(const std::string &new_username);
-    void set_propic(const image_pixels &new_propic);
+    void set_username(std::string new_username);
+    void set_propic(image_pixels new_propic);
 };
 
 using session_ptr = std::shared_ptr<game_session>;
diff --git a/src/net/manager.cpp b/src/net/manager.cpp
index 3ac03311..63cbabe6 100644
--- a/src/net/manager.cpp
+++ b/src/net/manager.cpp
@@ -136,7 +136,7 @@ static id_type generate_session_id(auto &rng, auto &map, int max_iters) {
     throw critical_error("CANNOT_GENERATE_SESSION_ID");
 }
 
-void game_manager::handle_message(utils::tag<"connect">, client_handle client, connection &con, const connect_args &args) {
+void game_manager::handle_message(utils::tag<"connect">, client_handle client, connection &con, connect_args args) {
     if (!std::holds_alternative<connection_state::not_validated>(con)) {
         throw lobby_error("USER_ALREADY_CONNECTED");
     }
@@ -155,8 +155,8 @@ void game_manager::handle_message(utils::tag<"connect">, client_handle client, c
         kick_client(session->client, "RECONNECT_WITH_SAME_SESSION_ID");
     }
 
-    session->set_username(args.username);
-    session->set_propic(args.propic);
+    session->set_username(std::move(args.username));
+    session->set_propic(std::move(args.propic));
     session->client = client;
     
     con.emplace<connection_state::connected>(session);
@@ -179,8 +179,8 @@ void game_manager::handle_message(utils::tag<"pong">, client_handle client, conn
     }
 }
 
-void game_manager::handle_message(utils::tag<"user_set_name">, session_ptr session, const std::string &username) {
-    session->set_username(username);
+void game_manager::handle_message(utils::tag<"user_set_name">, session_ptr session, std::string username) {
+    session->set_username(std::move(username));
 
     if (game_lobby *lobby = session->lobby) {
         game_user &user = lobby->find_user(session);
@@ -188,8 +188,8 @@ void game_manager::handle_message(utils::tag<"user_set_name">, session_ptr sessi
     }
 }
 
-void game_manager::handle_message(utils::tag<"user_set_propic">, session_ptr session, const image_pixels &propic) {
-    session->set_propic(propic);
+void game_manager::handle_message(utils::tag<"user_set_propic">, session_ptr session, image_pixels propic) {
+    session->set_propic(std::move(propic));
 
     if (game_lobby *lobby = session->lobby) {
         game_user &user = lobby->find_user(session);
diff --git a/src/net/manager.h b/src/net/manager.h
index 8396a70a..0c100ac1 100644
--- a/src/net/manager.h
+++ b/src/net/manager.h
@@ -69,10 +69,10 @@ class game_manager: public net::wsserver {
     bool remove_user_flag(session_ptr session, game_user_flag flag);
 
 private:
-    void handle_message(utils::tag<"connect">,        client_handle client, connection &con, const connect_args &value);
+    void handle_message(utils::tag<"connect">,        client_handle client, connection &con, connect_args value);
     void handle_message(utils::tag<"pong">,           client_handle client, connection &con);
-    void handle_message(utils::tag<"user_set_name">,  session_ptr session, const std::string &username);
-    void handle_message(utils::tag<"user_set_propic">, session_ptr session, const image_pixels &propic);
+    void handle_message(utils::tag<"user_set_name">,  session_ptr session, std::string username);
+    void handle_message(utils::tag<"user_set_propic">, session_ptr session, image_pixels propic);
     void handle_message(utils::tag<"lobby_make">,     session_ptr session, const lobby_make_args &value);
     void handle_message(utils::tag<"lobby_game_options">, session_ptr session, const game_options &options);
     void handle_message(utils::tag<"lobby_join">,     session_ptr session, const lobby_join_args &value);