diff --git a/examples/cli/main.cpp b/examples/cli/main.cpp
index 77ef1c9..86bc1ab 100644
--- a/examples/cli/main.cpp
+++ b/examples/cli/main.cpp
@@ -370,6 +370,95 @@ std::string format_frame_idx(std::string pattern, int frame_idx) {
     return result;
 }
 
+bool save_results(const SDCliParams& cli_params,
+                  const SDContextParams& ctx_params,
+                  const SDGenerationParams& gen_params,
+                  sd_image_t* results,
+                  int num_results) {
+    if (results == nullptr || num_results <= 0) {
+        return false;
+    }
+
+    namespace fs      = std::filesystem;
+    fs::path out_path = cli_params.output_path;
+
+    if (!out_path.parent_path().empty()) {
+        std::error_code ec;
+        fs::create_directories(out_path.parent_path(), ec);
+        if (ec) {
+            LOG_ERROR("failed to create directory '%s': %s",
+                      out_path.parent_path().string().c_str(), ec.message().c_str());
+            return false;
+        }
+    }
+
+    fs::path base_path = out_path;
+    fs::path ext       = out_path.has_extension() ? out_path.extension() : fs::path{};
+    if (!ext.empty())
+        base_path.replace_extension();
+
+    std::string ext_lower = ext.string();
+    std::transform(ext_lower.begin(), ext_lower.end(), ext_lower.begin(), ::tolower);
+    bool is_jpg = (ext_lower == ".jpg" || ext_lower == ".jpeg" || ext_lower == ".jpe");
+
+    int output_begin_idx = cli_params.output_begin_idx;
+    if (output_begin_idx < 0) {
+        output_begin_idx = 0;
+    }
+
+    auto write_image = [&](const fs::path& path, int idx) {
+        const sd_image_t& img = results[idx];
+        if (!img.data)
+            return;
+
+        std::string params = get_image_params(cli_params, ctx_params, gen_params, gen_params.seed + idx);
+        int ok             = 0;
+        if (is_jpg) {
+            ok = stbi_write_jpg(path.string().c_str(), img.width, img.height, img.channel, img.data, 90, params.c_str());
+        } else {
+            ok = stbi_write_png(path.string().c_str(), img.width, img.height, img.channel, img.data, 0, params.c_str());
+        }
+        LOG_INFO("save result image %d to '%s' (%s)", idx, path.string().c_str(), ok ? "success" : "failure");
+    };
+
+    if (std::regex_search(cli_params.output_path, format_specifier_regex)) {
+        if (!is_jpg && ext_lower != ".png")
+            ext = ".png";
+        fs::path pattern = base_path;
+        pattern += ext;
+
+        for (int i = 0; i < num_results; ++i) {
+            fs::path img_path = format_frame_idx(pattern.string(), output_begin_idx + i);
+            write_image(img_path, i);
+        }
+        return true;
+    }
+
+    if (cli_params.mode == VID_GEN && num_results > 1) {
+        if (ext_lower != ".avi")
+            ext = ".avi";
+        fs::path video_path = base_path;
+        video_path += ext;
+        create_mjpg_avi_from_sd_images(video_path.string().c_str(), results, num_results, gen_params.fps);
+        LOG_INFO("save result MJPG AVI video to '%s'", video_path.string().c_str());
+        return true;
+    }
+
+    if (!is_jpg && ext_lower != ".png")
+        ext = ".png";
+
+    for (int i = 0; i < num_results; ++i) {
+        fs::path img_path = base_path;
+        if (num_results > 1) {
+            img_path += "_" + std::to_string(output_begin_idx + i);
+        }
+        img_path += ext;
+        write_image(img_path, i);
+    }
+
+    return true;
+}
+
 int main(int argc, const char* argv[]) {
     if (argc > 1 && std::string(argv[1]) == "--version") {
         std::cout << version_string() << "\n";
@@ -713,101 +802,8 @@ int main(int argc, const char* argv[]) {
         }
     }
 
-    // create directory if not exists
-    {
-        const fs::path out_path = cli_params.output_path;
-        if (const fs::path out_dir = out_path.parent_path(); !out_dir.empty()) {
-            std::error_code ec;
-            fs::create_directories(out_dir, ec);  // OK if already exists
-            if (ec) {
-                LOG_ERROR("failed to create directory '%s': %s",
-                          out_dir.string().c_str(), ec.message().c_str());
-                return 1;
-            }
-        }
-    }
-
-    std::string base_path;
-    std::string file_ext;
-    std::string file_ext_lower;
-    bool is_jpg;
-    size_t last_dot_pos   = cli_params.output_path.find_last_of(".");
-    size_t last_slash_pos = std::min(cli_params.output_path.find_last_of("/"),
-                                     cli_params.output_path.find_last_of("\\"));
-    if (last_dot_pos != std::string::npos && (last_slash_pos == std::string::npos || last_dot_pos > last_slash_pos)) {  // filename has extension
-        base_path = cli_params.output_path.substr(0, last_dot_pos);
-        file_ext = file_ext_lower = cli_params.output_path.substr(last_dot_pos);
-        std::transform(file_ext.begin(), file_ext.end(), file_ext_lower.begin(), ::tolower);
-        is_jpg = (file_ext_lower == ".jpg" || file_ext_lower == ".jpeg" || file_ext_lower == ".jpe");
-    } else {
-        base_path = cli_params.output_path;
-        file_ext = file_ext_lower = "";
-        is_jpg                    = false;
-    }
-
-    if (std::regex_search(cli_params.output_path, format_specifier_regex)) {
-        std::string final_output_path = cli_params.output_path;
-        if (cli_params.output_begin_idx == -1) {
-            cli_params.output_begin_idx = 0;
-        }
-        // writing image sequence, default to PNG
-        if (!is_jpg && file_ext_lower != ".png") {
-            base_path += file_ext;
-            file_ext = ".png";
-        }
-        final_output_path = base_path + file_ext;
-        for (int i = 0; i < num_results; i++) {
-            if (results[i].data == nullptr) {
-                continue;
-            }
-            std::string final_image_path = format_frame_idx(final_output_path, cli_params.output_begin_idx + i);
-            if (is_jpg) {
-                int write_ok = stbi_write_jpg(final_image_path.c_str(), results[i].width, results[i].height, results[i].channel,
-                                              results[i].data, 90, get_image_params(cli_params, ctx_params, gen_params, gen_params.seed + i).c_str());
-                LOG_INFO("save result JPEG image %d to '%s' (%s)", i, final_image_path.c_str(), write_ok == 0 ? "failure" : "success");
-            } else {
-                int write_ok = stbi_write_png(final_image_path.c_str(), results[i].width, results[i].height, results[i].channel,
-                                              results[i].data, 0, get_image_params(cli_params, ctx_params, gen_params, gen_params.seed + i).c_str());
-                LOG_INFO("save result PNG image %d to '%s' (%s)", i, final_image_path.c_str(), write_ok == 0 ? "failure" : "success");
-            }
-        }
-    } else if (cli_params.mode == VID_GEN && num_results > 1) {
-        std::string final_output_path = cli_params.output_path;
-        if (file_ext_lower != ".avi") {
-            if (!is_jpg && file_ext_lower != ".png") {
-                base_path += file_ext;
-            }
-            file_ext          = ".avi";
-            final_output_path = base_path + file_ext;
-        }
-        create_mjpg_avi_from_sd_images(final_output_path.c_str(), results, num_results, gen_params.fps);
-        LOG_INFO("save result MJPG AVI video to '%s'\n", final_output_path.c_str());
-    } else {
-        // appending ".png" to absent or unknown extension
-        if (!is_jpg && file_ext_lower != ".png") {
-            base_path += file_ext;
-            file_ext = ".png";
-        }
-        if (cli_params.output_begin_idx == -1) {
-            cli_params.output_begin_idx = 1;
-        }
-        for (int i = 0; i < num_results; i++) {
-            if (results[i].data == nullptr) {
-                continue;
-            }
-            int write_ok;
-            std::string final_image_path;
-            final_image_path = i > 0 ? base_path + "_" + std::to_string(cli_params.output_begin_idx + i) + file_ext : base_path + file_ext;
-            if (is_jpg) {
-                write_ok = stbi_write_jpg(final_image_path.c_str(), results[i].width, results[i].height, results[i].channel,
-                                          results[i].data, 90, get_image_params(cli_params, ctx_params, gen_params, gen_params.seed + i).c_str());
-                LOG_INFO("save result JPEG image to '%s' (%s)", final_image_path.c_str(), write_ok == 0 ? "failure" : "success");
-            } else {
-                write_ok = stbi_write_png(final_image_path.c_str(), results[i].width, results[i].height, results[i].channel,
-                                          results[i].data, 0, get_image_params(cli_params, ctx_params, gen_params, gen_params.seed + i).c_str());
-                LOG_INFO("save result PNG image to '%s' (%s)", final_image_path.c_str(), write_ok == 0 ? "failure" : "success");
-            }
-        }
+    if (!save_results(cli_params, ctx_params, gen_params, results, num_results)) {
+        return 1;
     }
 
     for (int i = 0; i < num_results; i++) {