fix(encode): use modern nvenc low-latency preset

scripts/rtmp_srs_smoke.sh

@@ -7,6 +7,7 @@ SRS_ROOT="${SRS_ROOT:-$HOME/Code/srs}"
 SRS_BIN="${SRS_BIN:-$SRS_ROOT/trunk/objs/srs}"
 SRS_CONF="${SRS_CONF:-$SRS_ROOT/trunk/conf/srs.conf}"
 FFPROBE_BIN="${FFPROBE_BIN:-ffprobe}"
+ENCODER_DEVICE="${ENCODER_DEVICE:-software}"
 
 wait_for_port() {
 	local host="$1"
@@ -48,7 +49,7 @@ wait_for_stream() {
 run_case() {
 	local transport="$1"
 	local codec="$2"
-	local stream_name="cvmmap_${transport}_${codec}"
+	local stream_name="cvmmap_${transport}_${codec}_${ENCODER_DEVICE}"
 	local expected_codec="$codec"
 	if [[ "$codec" == "h265" ]]; then
 		expected_codec="hevc"
@@ -57,6 +58,7 @@ run_case() {
 	"${BUILD_DIR}/rtmp_output_tester" \
 		--transport "$transport" \
 		--codec "$codec" \
+		--encoder-device "$ENCODER_DEVICE" \
 		--rtmp-url "rtmp://127.0.0.1/live/${stream_name}" \
 		--frames 36 \
 		--frame-interval-ms 33 \

src/encode/ffmpeg_encoder_backend.cpp

@@ -345,7 +345,7 @@ private:
 
 	[[nodiscard]]
 	Status configure_codec(std::string_view encoder_name, const RuntimeConfig &config) {
-		av_opt_set(context_->priv_data, "preset", encoder_name.find("nvenc") != std::string_view::npos ? "llhq" : "veryfast", 0);
+		av_opt_set(context_->priv_data, "preset", encoder_name.find("nvenc") != std::string_view::npos ? "p1" : "veryfast", 0);
 		if (encoder_name.find("nvenc") != std::string_view::npos) {
 			av_opt_set(context_->priv_data, "tune", "ull", 0);
 			av_opt_set(context_->priv_data, "zerolatency", "1", 0);

src/testers/rtmp_output_tester.cpp

@@ -40,6 +40,7 @@ struct Config {
 	std::string rtmp_url{"rtmp://127.0.0.1/live/cvmmap_streamer_test"};
 	std::string transport{"libavformat"};
 	std::string codec{"h264"};
+	std::string encoder_device{"software"};
 	std::string ffmpeg_path{"ffmpeg"};
 	std::uint32_t frames{48};
 	std::uint32_t width{320};
@@ -57,6 +58,8 @@ std::expected<Config, int> parse_args(int argc, char **argv) {
 		->check(CLI::IsMember({"libavformat", "ffmpeg_process", "legacy_custom"}));
 	app.add_option("--codec", config.codec, "Video codec (h264|h265)")
 		->check(CLI::IsMember({"h264", "h265"}));
+	app.add_option("--encoder-device", config.encoder_device, "Encoder device (auto|nvidia|software)")
+		->check(CLI::IsMember({"auto", "nvidia", "software"}));
 	app.add_option("--ffmpeg-path", config.ffmpeg_path, "ffmpeg binary path for ffmpeg_process transport");
 	app.add_option("--frames", config.frames, "Number of frames to publish")->check(CLI::PositiveNumber);
 	app.add_option("--width", config.width, "Frame width")->check(CLI::PositiveNumber);
@@ -98,6 +101,20 @@ std::expected<cvmmap_streamer::RtmpTransportType, std::string> parse_transport(s
 	return std::unexpected("unsupported transport");
 }
 
+[[nodiscard]]
+std::expected<cvmmap_streamer::EncoderDeviceType, std::string> parse_encoder_device(std::string_view raw) {
+	if (raw == "auto") {
+		return cvmmap_streamer::EncoderDeviceType::Auto;
+	}
+	if (raw == "nvidia") {
+		return cvmmap_streamer::EncoderDeviceType::Nvidia;
+	}
+	if (raw == "software") {
+		return cvmmap_streamer::EncoderDeviceType::Software;
+	}
+	return std::unexpected("unsupported encoder device");
+}
+
 void fill_pattern(std::vector<std::uint8_t> &buffer, std::uint32_t width, std::uint32_t height, std::uint32_t frame_index) {
 	for (std::uint32_t y = 0; y < height; ++y) {
 		for (std::uint32_t x = 0; x < width; ++x) {
@@ -129,9 +146,15 @@ int main(int argc, char **argv) {
 		return exit_code(TesterExitCode::InvalidArgument);
 	}
 
+	auto encoder_device = parse_encoder_device(args->encoder_device);
+	if (!encoder_device) {
+		spdlog::error("{}", encoder_device.error());
+		return exit_code(TesterExitCode::InvalidArgument);
+	}
+
 	cvmmap_streamer::RuntimeConfig config = cvmmap_streamer::RuntimeConfig::defaults();
 	config.encoder.backend         = cvmmap_streamer::EncoderBackendType::FFmpeg;
-	config.encoder.device          = cvmmap_streamer::EncoderDeviceType::Software;
+	config.encoder.device          = *encoder_device;
 	config.encoder.codec           = *codec;
 	config.encoder.gop             = 15;
 	config.encoder.b_frames        = 0;