diff --git a/libs/gfx/include/psemek/gfx/pixmap.hpp b/libs/gfx/include/psemek/gfx/pixmap.hpp
index 1a1e9b56..a71657da 100644
--- a/libs/gfx/include/psemek/gfx/pixmap.hpp
+++ b/libs/gfx/include/psemek/gfx/pixmap.hpp
@@ -27,6 +27,8 @@ namespace psemek::gfx
 	pixmap_rgba read_png(io::istream && is);
 	pixmap_monochrome read_png_monochrome(io::istream && is);
 
+	void write_png(pixmap_rgba const & p, io::ostream && os);
+
 	template <typename Pixel, std::size_t N>
 	auto to_srgb(util::array<Pixel, N> pm, float g = 1.f / 2.2f)
 	{
diff --git a/libs/gfx/source/png.cpp b/libs/gfx/source/png.cpp
index 24d6c9f9..979e1623 100644
--- a/libs/gfx/source/png.cpp
+++ b/libs/gfx/source/png.cpp
@@ -8,76 +8,123 @@
 namespace psemek::gfx
 {
 
-	template <typename Pixel>
-	basic_pixmap<Pixel> read_png_impl(io::istream & is, bool monochrome)
+	namespace
 	{
-		png_error_ptr error = [](png_structp, png_const_charp str)
+
+		template <typename Pixel>
+		basic_pixmap<Pixel> read_png_impl(io::istream & is, bool monochrome)
 		{
-			throw std::runtime_error(str);
-		};
+			png_error_ptr error = [](png_structp, png_const_charp str)
+			{
+				throw std::runtime_error(str);
+			};
 
-		png_error_ptr warn = [](png_structp, png_const_charp str)
+			png_error_ptr warn = [](png_structp, png_const_charp str)
+			{
+				log::warning() << str;
+			};
+
+			auto png = png_create_read_struct(PNG_LIBPNG_VER_STRING, nullptr, error, warn);
+			if (!png) throw std::runtime_error("png_create_read_struct returned null");
+
+			png_set_error_fn(png, nullptr, error, warn);
+
+			png_infop info = nullptr;
+			png_infop end_info = nullptr;
+
+			[[maybe_unused]] auto png_dtor = util::at_scope_exit([&]{
+				png_destroy_read_struct(&png, &info, &end_info);
+			});
+
+			info = png_create_info_struct(png);
+			if (!info) throw std::runtime_error("png_create_info_struct returned null");
+
+			end_info = png_create_info_struct(png);
+			if (!end_info) throw std::runtime_error("png_create_info_struct returned null");
+
+			png_rw_ptr read = [](png_structp png, png_bytep ptr, size_t count){
+				reinterpret_cast<io::istream *>(png_get_io_ptr(png))->read(reinterpret_cast<char *>(ptr), count);
+			};
+			png_set_read_fn(png, &is, read);
+
+			png_read_info(png, info);
+
+			auto const width = png_get_image_width(png, info);
+			auto const height = png_get_image_height(png, info);
+			auto const color_type = png_get_color_type(png, info);
+			auto const bit_depth = png_get_bit_depth(png, info);
+
+			if (bit_depth == 16)
+				png_set_strip_16(png);
+
+			if (monochrome && color_type != PNG_COLOR_TYPE_GRAY)
+				throw std::runtime_error("invalid color type for monochrome PNG");
+
+			if (color_type == PNG_COLOR_TYPE_PALETTE)
+				png_set_palette_to_rgb(png);
+
+			if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+				png_set_expand_gray_1_2_4_to_8(png);
+
+			if (color_type == PNG_COLOR_TYPE_RGB)
+				png_set_add_alpha(png, 0xff, PNG_FILLER_AFTER);
+
+			png_read_update_info(png, info);
+
+			basic_pixmap<Pixel> result({width, height});
+
+			auto const row_bytes = png_get_rowbytes(png, info);
+			if (row_bytes != width * sizeof(Pixel))
+				throw std::runtime_error("PNG row bytes mismatch");
+
+			for (std::uint32_t i = 0; i < height; ++i)
+				png_read_row(png, reinterpret_cast<png_bytep>(result.data() + i * width), nullptr);
+
+			return result;
+		}
+
+		void write_png_impl(pixmap_rgba const & p, io::ostream & os)
 		{
-			log::warning() << str;
-		};
+			png_error_ptr error = [](png_structp, png_const_charp str)
+			{
+				throw std::runtime_error(str);
+			};
 
-		auto png = png_create_read_struct(PNG_LIBPNG_VER_STRING, nullptr, error, warn);
-		if (!png) throw std::runtime_error("png_create_read_struct returned null");
+			png_error_ptr warn = [](png_structp, png_const_charp str)
+			{
+				log::warning() << str;
+			};
 
-		png_set_error_fn(png, nullptr, error, warn);
+			auto png = png_create_write_struct(PNG_LIBPNG_VER_STRING, nullptr, error, warn);
+			if (!png) throw std::runtime_error("png_create_write_struct returned null");
 
-		png_infop info = nullptr;
-		png_infop end_info = nullptr;
+			png_set_error_fn(png, nullptr, error, warn);
 
-		[[maybe_unused]] auto png_dtor = util::at_scope_exit([&]{
-			png_destroy_read_struct(&png, &info, &end_info);
-		});
+			png_infop info = nullptr;
 
-		info = png_create_info_struct(png);
-		if (!info) throw std::runtime_error("png_create_info_struct returned null");
+			[[maybe_unused]] auto png_dtor = util::at_scope_exit([&]{
+				png_destroy_write_struct(&png, &info);
+			});
 
-		end_info = png_create_info_struct(png);
-		if (!end_info) throw std::runtime_error("png_create_info_struct returned null");
+			info = png_create_info_struct(png);
+			if (!info) throw std::runtime_error("png_create_info_struct returned null");
 
-		png_rw_ptr read = [](png_structp png, png_bytep ptr, size_t count){
-			reinterpret_cast<io::istream *>(png_get_io_ptr(png))->read(reinterpret_cast<char *>(ptr), count);
-		};
-		png_set_read_fn(png, &is, read);
+			png_rw_ptr write = [](png_structp png, png_bytep ptr, size_t count){
+				reinterpret_cast<io::ostream *>(png_get_io_ptr(png))->write(reinterpret_cast<char const *>(ptr), count);
+			};
+			png_flush_ptr flush = [](png_structp png){
+				reinterpret_cast<io::ostream *>(png_get_io_ptr(png))->flush();
+			};
+			png_set_write_fn(png, &os, write, flush);
 
-		png_read_info(png, info);
+			png_set_IHDR(png, info, p.width(), p.height(), 8, PNG_COLOR_TYPE_RGBA, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
 
-		auto const width = png_get_image_width(png, info);
-		auto const height = png_get_image_height(png, info);
-		auto const color_type = png_get_color_type(png, info);
-		auto const bit_depth = png_get_bit_depth(png, info);
+			png_write_info(png, info);
 
-		if (bit_depth == 16)
-			png_set_strip_16(png);
+			for (std::uint32_t i = 0; i < p.height(); ++i)
+				png_write_row(png, reinterpret_cast<png_byte const *>(p.data() + p.width() * i));
+		}
 
-		if (monochrome && color_type != PNG_COLOR_TYPE_GRAY)
-			throw std::runtime_error("invalid color type for monochrome PNG");
-
-		if (color_type == PNG_COLOR_TYPE_PALETTE)
-			png_set_palette_to_rgb(png);
-
-		if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
-			png_set_expand_gray_1_2_4_to_8(png);
-
-		if (color_type == PNG_COLOR_TYPE_RGB)
-			png_set_add_alpha(png, 0xff, PNG_FILLER_AFTER);
-
-		png_read_update_info(png, info);
-
-		basic_pixmap<Pixel> result({width, height});
-
-		auto const row_bytes = png_get_rowbytes(png, info);
-		if (row_bytes != width * sizeof(Pixel))
-			throw std::runtime_error("PNG row bytes mismatch");
-
-		for (std::uint32_t i = 0; i < height; ++i)
-			png_read_row(png, reinterpret_cast<png_bytep>(result.data() + i * width), nullptr);
-
-		return result;
 	}
 
 	pixmap_rgba read_png(io::istream && is)
@@ -90,4 +137,9 @@ namespace psemek::gfx
 		return read_png_impl<std::uint8_t>(is, true);
 	}
 
+	void write_png(pixmap_rgba const & p, io::ostream && os)
+	{
+		write_png_impl(p, os);
+	}
+
 }