encoders/handlers/nvenc: Don't list encoders on unsupported systems

Removes the NVENC entry on systems without an NVIDIA GPU by checking if the library for it can be loaded. If it can't be loaded, it's likely that the user does not have a system with NVENC capabilities - and guaranteed that they can't use the encoder as FFmpeg relies on these libraries.

source/encoders/handlers/nvenc_h264_handler.cpp

@@ -59,9 +59,11 @@ static std::map<level, std::string> levels{
 	{level::L4_1, "4.1"}, {level::L4_2, "4.2"},   {level::L5_0, "5.0"}, {level::L5_1, "5.1"},
 };
 
-void nvenc_h264_handler::adjust_info(ffmpeg_factory*, const AVCodec*, std::string&, std::string& name, std::string&)
+void nvenc_h264_handler::adjust_info(ffmpeg_factory* fac, const AVCodec*, std::string&, std::string& name, std::string&)
 {
 	name = "NVIDIA NVENC H.264/AVC (via FFmpeg)";
+	if (!nvenc::is_available())
+		fac->get_info()->caps |= OBS_ENCODER_CAP_DEPRECATED;
 }
 
 void nvenc_h264_handler::get_defaults(obs_data_t* settings, const AVCodec* codec, AVCodecContext* context, bool)

source/encoders/handlers/nvenc_hevc_handler.cpp

@@ -59,9 +59,11 @@ static std::map<level, std::string> levels{
 	{level::L6_0, "6.0"}, {level::L6_1, "6.1"}, {level::L6_2, "6.2"},
 };
 
-void nvenc_hevc_handler::adjust_info(ffmpeg_factory*, const AVCodec*, std::string&, std::string& name, std::string&)
+void nvenc_hevc_handler::adjust_info(ffmpeg_factory* fac, const AVCodec*, std::string&, std::string& name, std::string&)
 {
 	name = "NVIDIA NVENC H.265/HEVC (via FFmpeg)";
+	if (!nvenc::is_available())
+		fac->get_info()->caps |= OBS_ENCODER_CAP_DEPRECATED;
 }
 
 void nvenc_hevc_handler::get_defaults(obs_data_t* settings, const AVCodec* codec, AVCodecContext* context, bool)

source/encoders/handlers/nvenc_shared.cpp

@@ -20,15 +20,10 @@
 // SOFTWARE.
 
 #include "nvenc_shared.hpp"
-#include "strings.hpp"
+#include "encoders/encoder-ffmpeg.hpp"
-#include <algorithm>
-#include "../codecs/hevc.hpp"
-#include "../encoder-ffmpeg.hpp"
 #include "ffmpeg/tools.hpp"
-#include "plugin.hpp"
 
 extern "C" {
-#include <obs-module.h>
 #pragma warning(push)
 #pragma warning(disable : 4244)
 #include <libavutil/opt.h>
@@ -155,6 +150,25 @@ std::map<nvenc::b_ref_mode, std::string> nvenc::b_ref_mode_to_opt{
 	{nvenc::b_ref_mode::MIDDLE, "middle"},
 };
 
+bool streamfx::encoder::ffmpeg::handler::nvenc::is_available()
+{
+#if defined(D_PLATFORM_WINDOWS)
+#if defined(D_PLATFORM_64BIT)
+	std::filesystem::path lib_name = "nvEncodeAPI64.dll";
+#else
+	std::filesystem::path lib_name = "nvEncodeAPI.dll";
+#endif
+#else
+	std::filesystem::path lib_name = "libnvidia-encode.so.1";
+#endif
+	try {
+		util::library::load(lib_name);
+		return true;
+	} catch (...) {
+		return false;
+	}
+}
+
 void nvenc::override_update(ffmpeg_instance* instance, obs_data_t*)
 {
 	AVCodecContext* context = const_cast<AVCodecContext*>(instance->get_avcodeccontext());

source/encoders/handlers/nvenc_shared.hpp

@@ -20,7 +20,7 @@
 // SOFTWARE.
 
 #pragma once
-#include <map>
+#include "common.hpp"
 #include "handler.hpp"
 
 extern "C" {
@@ -90,6 +90,8 @@ namespace streamfx::encoder::ffmpeg::handler::nvenc {
 
 	extern std::map<b_ref_mode, std::string> b_ref_mode_to_opt;
 
+	bool is_available();
+
 	void override_update(ffmpeg_instance* instance, obs_data_t* settings);
 
 	void get_defaults(obs_data_t* settings, const AVCodec* codec, AVCodecContext* context);