HEVC (and some other small shit)

Overlord-Client/cmd/agent/capture/capture.go

@@ -111,7 +111,7 @@ func CaptureAndSend(ctx context.Context, env *rt.Env) error {
 	if frame, captureDur, encodeDur, used, err := tryBuildDirectH264Frame(display); used {
 		if err != nil {
 			consecutiveCaptureFails.Add(1)
-			log.Printf("capture: direct h264 capture failed: %v (sending black frame, consecutive=%d)", err, consecutiveCaptureFails.Load())
+			log.Printf("capture: direct video capture failed: %v (sending black frame, consecutive=%d)", err, consecutiveCaptureFails.Load())
 			return sendBlackFrame(ctx, env)
 		}
 		if len(frame.Data) == 0 {
@@ -513,6 +513,7 @@ var (
 	overrideCodec       atomic.Value
 	desktopSoftwareH264 atomic.Bool
 	h264WarnOnce        sync.Once
+	hevcWarnOnce        sync.Once
 	codecLogOnce        sync.Once
 
 	prevMu    sync.Mutex
@@ -756,6 +757,33 @@ func buildFrame(img *image.RGBA, display int, quality int) (wire.Frame, time.Dur
 	full := false
 	now := time.Now()
 	codec := blockCodec()
+	if codec == "hevc" {
+		if width%2 != 0 || height%2 != 0 {
+			log.Printf("capture: hevc skipped for odd dimensions (%dx%d), falling back to h264/jpeg", width, height)
+			codec = "h264"
+		} else {
+			if webrtcpub.ConsumeKeyframeRequest() {
+				resetHEVCEncoder()
+			}
+			hevcBytes, err := encodeHEVCFrame(img)
+			if err == nil && len(hevcBytes) > 0 {
+				lastKeyframe.Store(now.UnixNano())
+				statFullFrames.Add(1)
+				return wire.Frame{Type: "frame", Header: wire.FrameHeader{Monitor: display, FPS: 0, Format: "hevc"}, Data: hevcBytes}, time.Since(encStart), nil
+			}
+			hevcWarnOnce.Do(func() {
+				log.Printf("capture: hevc encode unavailable, falling back to h264/jpeg: %v (%s)", err, hevcAvailabilityDetail())
+			})
+			resetHEVCEncoder()
+			if h264Available() {
+				codec = "h264"
+				overrideCodec.Store("h264")
+			} else {
+				codec = "jpeg"
+				overrideCodec.Store("jpeg")
+			}
+		}
+	}
 
 	if codec == "h264" {
 		if width%2 != 0 || height%2 != 0 {
@@ -1567,6 +1595,8 @@ func blockCodec() string {
 		switch codec {
 		case "h264":
 			cachedBlockCodec = "h264"
+		case "hevc", "h265":
+			cachedBlockCodec = "hevc"
 		case "raw", "rgba":
 			cachedBlockCodec = "raw"
 		case "jpeg", "":
@@ -1586,6 +1616,18 @@ func SetQualityAndCodec(quality int, codec string) {
 		overrideQuality.Store(int64(quality))
 	}
 	s := strings.ToLower(strings.TrimSpace(codec))
+	if s == "h265" {
+		s = "hevc"
+	}
+	if s == "hevc" && !hevcAvailable() {
+		detail := hevcAvailabilityDetail()
+		fallback := "jpeg"
+		if h264Available() {
+			fallback = "h264"
+		}
+		log.Printf("capture: requested codec=hevc but unavailable (%s); forcing codec=%s", detail, fallback)
+		s = fallback
+	}
 	if s == "h264" && !h264Available() {
 		detail := h264AvailabilityDetail()
 		if detail != "" {
@@ -1596,19 +1638,24 @@ func SetQualityAndCodec(quality int, codec string) {
 		s = "jpeg"
 	}
 	switch s {
-	case "raw", "rgba", "jpeg", "h264":
+	case "raw", "rgba", "jpeg", "h264", "hevc":
 		overrideCodec.Store(s)
 		h264WarnOnce = sync.Once{}
+		hevcWarnOnce = sync.Once{}
 		if s != "h264" {
 			resetH264Encoder()
 			resetH264Encoderbackstage()
 		}
+		if s != "hevc" {
+			resetHEVCEncoder()
+		}
 	case "":
 
 	default:
 		overrideCodec.Store("jpeg")
 		resetH264Encoder()
 		resetH264Encoderbackstage()
+		resetHEVCEncoder()
 	}
 }
 

Overlord-Client/cmd/agent/capture/desktop_encoder_capabilities.go

@@ -9,9 +9,59 @@ type DesktopEncoderProfile struct {
 	Providers []string `msgpack:"providers" json:"providers"`
 }
 
+type DesktopCodecCapability struct {
+	Codec      string   `msgpack:"codec" json:"codec"`
+	Encoders   []string `msgpack:"encoders,omitempty" json:"encoders,omitempty"`
+	Transports []string `msgpack:"transports" json:"transports"`
+	Hardware   bool     `msgpack:"hardware,omitempty" json:"hardware,omitempty"`
+}
+
 type DesktopEncoderCapabilities struct {
-	Probed   bool                    `msgpack:"probed" json:"probed"`
-	Display  int                     `msgpack:"display" json:"display"`
-	Profiles []DesktopEncoderProfile `msgpack:"profiles" json:"profiles"`
-	Detail   string                  `msgpack:"detail,omitempty" json:"detail,omitempty"`
+	Probed   bool                     `msgpack:"probed" json:"probed"`
+	Display  int                      `msgpack:"display" json:"display"`
+	Profiles []DesktopEncoderProfile  `msgpack:"profiles" json:"profiles"`
+	Codecs   []DesktopCodecCapability `msgpack:"codecs" json:"codecs"`
+	Detail   string                   `msgpack:"detail,omitempty" json:"detail,omitempty"`
+}
+
+func completeDesktopEncoderCapabilities(caps DesktopEncoderCapabilities) DesktopEncoderCapabilities {
+	encoders := make([]string, 0)
+	hardware := false
+	for _, profile := range caps.Profiles {
+		for _, provider := range profile.Providers {
+			encoders = appendDesktopUniqueString(encoders, provider)
+			if provider != "" && provider != "Software H.264 / JPEG" {
+				hardware = true
+			}
+		}
+	}
+	caps.Codecs = []DesktopCodecCapability{
+		{Codec: "jpeg", Encoders: []string{"Software JPEG"}, Transports: []string{"websocket"}},
+		{Codec: "raw", Encoders: []string{"Uncompressed"}, Transports: []string{"websocket"}},
+	}
+	if hevcAvailable() {
+		caps.Codecs = append([]DesktopCodecCapability{{
+			Codec: "hevc", Encoders: []string{"NVIDIA NVENC"},
+			Transports: []string{"websocket"}, Hardware: true,
+		}}, caps.Codecs...)
+	}
+	if h264Available() {
+		if len(encoders) == 0 {
+			encoders = []string{"Software H.264"}
+		}
+		caps.Codecs = append([]DesktopCodecCapability{{
+			Codec: "h264", Encoders: encoders,
+			Transports: []string{"websocket", "webrtc"}, Hardware: hardware,
+		}}, caps.Codecs...)
+	}
+	return caps
+}
+
+func appendDesktopUniqueString(values []string, value string) []string {
+	for _, existing := range values {
+		if existing == value {
+			return values
+		}
+	}
+	return append(values, value)
 }

Overlord-Client/cmd/agent/capture/desktop_encoder_capabilities_stub.go

@@ -3,12 +3,12 @@
 package capture
 
 func ProbeDesktopEncoderCapabilities(display int) DesktopEncoderCapabilities {
-	return DesktopEncoderCapabilities{
+	return completeDesktopEncoderCapabilities(DesktopEncoderCapabilities{
 		Display: display,
 		Profiles: []DesktopEncoderProfile{
 			{MaxHeight: 720, Width: 1280, Height: 720, FPS: 60, Label: "60 FPS - 720p", Providers: []string{"Software H.264 / JPEG"}},
 			{MaxHeight: 1080, Width: 1920, Height: 1080, FPS: 60, Label: "60 FPS - 1080p", Providers: []string{"Software H.264 / JPEG"}},
 		},
 		Detail: "Hardware H.264 capability probing is available on Windows; safe software profiles are shown.",
-	}
+	})
 }

Overlord-Client/cmd/agent/capture/desktop_encoder_capabilities_test.go

@@ -0,0 +1,46 @@
+package capture
+
+import "testing"
+
+func TestCompleteDesktopEncoderCapabilitiesAdvertisesUsableCodecs(t *testing.T) {
+	caps := completeDesktopEncoderCapabilities(DesktopEncoderCapabilities{
+		Profiles: []DesktopEncoderProfile{{
+			MaxHeight: 1080,
+			Width:     1920,
+			Height:    1080,
+			FPS:       60,
+			Providers: []string{"Software H.264 / JPEG"},
+		}},
+	})
+
+	byName := make(map[string]DesktopCodecCapability)
+	for _, codec := range caps.Codecs {
+		byName[codec.Codec] = codec
+	}
+	if _, ok := byName["jpeg"]; !ok {
+		t.Fatal("expected JPEG capability")
+	}
+	if _, ok := byName["raw"]; !ok {
+		t.Fatal("expected raw capability")
+	}
+	if h264Available() {
+		h264, ok := byName["h264"]
+		if !ok {
+			t.Fatal("expected H.264 capability when the encoder is available")
+		}
+		if len(h264.Transports) != 2 || h264.Transports[0] != "websocket" || h264.Transports[1] != "webrtc" {
+			t.Fatalf("unexpected H.264 transports: %v", h264.Transports)
+		}
+	}
+	if hevcAvailable() {
+		hevc, ok := byName["hevc"]
+		if !ok {
+			t.Fatal("expected HEVC capability when NVENC HEVC is available")
+		}
+		if len(hevc.Transports) != 1 || hevc.Transports[0] != "websocket" || !hevc.Hardware {
+			t.Fatalf("unexpected HEVC capability: %+v", hevc)
+		}
+	} else if _, ok := byName["hevc"]; ok {
+		t.Fatal("must not advertise HEVC when NVENC HEVC is unavailable")
+	}
+}

Overlord-Client/cmd/agent/capture/desktop_encoder_capabilities_windows.go

@@ -44,6 +44,7 @@ func ProbeDesktopEncoderCapabilities(display int) DesktopEncoderCapabilities {
 		return cached.caps
 	}
 	caps := probeDesktopEncoderCapabilities(display, bounds)
+	caps = completeDesktopEncoderCapabilities(caps)
 	desktopCapabilityCache.entries[cacheKey] = desktopCapabilityCacheEntry{at: time.Now(), caps: caps}
 	for key, entry := range desktopCapabilityCache.entries {
 		if time.Since(entry.at) >= desktopCapabilityCacheTTL {

Overlord-Client/cmd/agent/capture/h264_direct_windows.go

@@ -10,11 +10,21 @@ import (
 )
 
 func tryBuildDirectH264Frame(display int) (wire.Frame, time.Duration, time.Duration, bool, error) {
-	if blockCodec() != "h264" || useDesktopSoftwareH264() || !useDesktopDuplication() {
+	codec := blockCodec()
+	if (codec != "h264" && codec != "hevc") || (codec == "h264" && useDesktopSoftwareH264()) || !useDesktopDuplication() {
 		return wire.Frame{}, 0, 0, false, nil
 	}
 	forceKeyframe := webrtcpub.ConsumeKeyframeRequest()
-	data, width, height, captureDur, encodeDur, used, err := captureDisplayDXGIH264(display, forceKeyframe)
+	var data []byte
+	var width, height int
+	var captureDur, encodeDur time.Duration
+	var used bool
+	var err error
+	if codec == "hevc" {
+		data, width, height, captureDur, encodeDur, used, err = captureDisplayDXGIHEVC(display, forceKeyframe)
+	} else {
+		data, width, height, captureDur, encodeDur, used, err = captureDisplayDXGIH264(display, forceKeyframe)
+	}
 	if !used || err != nil {
 		return wire.Frame{}, captureDur, encodeDur, used, err
 	}
@@ -24,5 +34,5 @@ func tryBuildDirectH264Frame(display int) (wire.Frame, time.Duration, time.Durat
 	now := time.Now()
 	lastKeyframe.Store(now.UnixNano())
 	statFullFrames.Add(1)
-	return wire.Frame{Type: "frame", Header: wire.FrameHeader{Monitor: display, FPS: 0, Format: "h264", Width: width, Height: height}, Data: data}, captureDur, encodeDur, true, nil
+	return wire.Frame{Type: "frame", Header: wire.FrameHeader{Monitor: display, FPS: 0, Format: codec, Width: width, Height: height}, Data: data}, captureDur, encodeDur, true, nil
 }

Overlord-Client/cmd/agent/capture/hevc_codec_test.go

@@ -0,0 +1,86 @@
+package capture
+
+import (
+	"image"
+	"testing"
+)
+
+func TestHEVCEncoderProducesAnnexBHeadersAndKeyframe(t *testing.T) {
+	if !hevcAvailable() {
+		t.Skipf("HEVC encoder unavailable: %s", hevcAvailabilityDetail())
+	}
+	resetHEVCEncoder()
+	t.Cleanup(resetHEVCEncoder)
+
+	frame := image.NewRGBA(image.Rect(0, 0, 1280, 720))
+	encoded, err := encodeHEVCFrame(frame)
+	if err != nil {
+		t.Fatalf("encode HEVC frame: %v", err)
+	}
+	if len(encoded) == 0 {
+		t.Fatal("HEVC encoder returned an empty frame")
+	}
+
+	nalTypes := hevcAnnexBNALTypes(encoded)
+	for _, required := range []byte{32, 33, 34} {
+		if !containsByte(nalTypes, required) {
+			t.Fatalf("HEVC frame missing NAL type %d; got %v", required, nalTypes)
+		}
+	}
+	hasIntra := false
+	for _, nalType := range nalTypes {
+		if nalType >= 16 && nalType <= 21 {
+			hasIntra = true
+			break
+		}
+	}
+	if !hasIntra {
+		t.Fatalf("HEVC first frame is not an IRAP keyframe; got NAL types %v", nalTypes)
+	}
+}
+
+func TestHEVCD3D11TexturePipeline(t *testing.T) {
+	if !hevcAvailable() {
+		t.Skipf("HEVC encoder unavailable: %s", hevcAvailabilityDetail())
+	}
+	result := RunNVENCD3D11Smoke(NVENCD3D11SmokeOptions{
+		Width: 1280, Height: 720, FPS: 60, Frames: 4, Codec: "hevc",
+	})
+	if !result.OK {
+		t.Fatalf("HEVC D3D11 texture pipeline failed: %+v", result)
+	}
+	if result.TotalBytes == 0 {
+		t.Fatal("HEVC D3D11 texture pipeline produced no output")
+	}
+	t.Logf("HEVC D3D11 texture pipeline: first=%.2fms avg=%.2fms bytes=%d", result.FirstMS, result.AvgMS, result.TotalBytes)
+}
+
+func hevcAnnexBNALTypes(data []byte) []byte {
+	types := make([]byte, 0, 8)
+	for i := 0; i+4 < len(data); i++ {
+		startCodeLen := 0
+		if data[i] == 0 && data[i+1] == 0 && data[i+2] == 1 {
+			startCodeLen = 3
+		} else if i+4 < len(data) && data[i] == 0 && data[i+1] == 0 && data[i+2] == 0 && data[i+3] == 1 {
+			startCodeLen = 4
+		}
+		if startCodeLen == 0 {
+			continue
+		}
+		nalIndex := i + startCodeLen
+		if nalIndex < len(data) {
+			types = append(types, (data[nalIndex]>>1)&0x3f)
+			i = nalIndex
+		}
+	}
+	return types
+}
+
+func containsByte(values []byte, wanted byte) bool {
+	for _, value := range values {
+		if value == wanted {
+			return true
+		}
+	}
+	return false
+}

Overlord-Client/cmd/agent/capture/hevc_encoder_stub.go

@@ -0,0 +1,18 @@
+//go:build !windows
+
+package capture
+
+import (
+	"errors"
+	"image"
+)
+
+func encodeHEVCFrame(_ *image.RGBA) ([]byte, error) {
+	return nil, errors.New("HEVC NVENC is only available on Windows")
+}
+
+func hevcAvailable() bool { return false }
+
+func hevcAvailabilityDetail() string { return "HEVC NVENC is only available on Windows" }
+
+func resetHEVCEncoder() {}

Overlord-Client/cmd/agent/capture/hevc_encoder_windows.go

@@ -0,0 +1,68 @@
+//go:build windows
+
+package capture
+
+import (
+	"errors"
+	"fmt"
+	"image"
+	"sync"
+)
+
+var (
+	hevcMu          sync.Mutex
+	hevcEnc         h264FrameEncoder
+	hevcProbeOnce   sync.Once
+	hevcProbeOK     bool
+	hevcProbeDetail string
+)
+
+func encodeHEVCFrame(img *image.RGBA) ([]byte, error) {
+	if img == nil {
+		return nil, errors.New("nil hevc frame")
+	}
+	b := img.Bounds()
+	width, height := b.Dx(), b.Dy()
+	if width <= 0 || height <= 0 || width%2 != 0 || height%2 != 0 {
+		return nil, fmt.Errorf("hevc frame size must be positive and even, got %dx%d", width, height)
+	}
+
+	hevcMu.Lock()
+	defer hevcMu.Unlock()
+	fps := activeH264FPS()
+	if hevcEnc == nil || !hevcEnc.Matches(width, height, fps) {
+		closeH264Encoder(&hevcEnc)
+		enc, err := newNativeHEVCEncoder("desktop", width, height, fps)
+		if err != nil {
+			return nil, err
+		}
+		hevcEnc = enc
+	}
+	return hevcEnc.Encode(img)
+}
+
+func hevcAvailable() bool {
+	hevcProbeOnce.Do(func() {
+		enc, err := newNativeHEVCEncoder("probe", 1280, 720, 30)
+		if err != nil {
+			hevcProbeDetail = err.Error()
+			return
+		}
+		enc.Close()
+		hevcProbeOK = true
+		hevcProbeDetail = "NVIDIA NVENC HEVC Main profile"
+	})
+	return hevcProbeOK
+}
+
+func hevcAvailabilityDetail() string {
+	hevcAvailable()
+	return hevcProbeDetail
+}
+
+func resetHEVCEncoder() {
+	hevcMu.Lock()
+	defer hevcMu.Unlock()
+	closeH264Encoder(&hevcEnc)
+	resetNativeHEVCD3D11TextureEncoder()
+}

Overlord-Client/cmd/agent/capture/native_h264_stub_windows.go

@@ -9,6 +9,10 @@ func newNativeH264Encoder(stream string, width, height, fps int) (h264FrameEncod
 	return nil, fmt.Errorf("native NVENC D3D11 requires cgo for %dx%d@%dfps", width, height, fps)
 }
 
+func newNativeHEVCEncoder(stream string, width, height, fps int) (h264FrameEncoder, error) {
+	return nil, fmt.Errorf("native NVENC HEVC requires cgo for %dx%d@%dfps", width, height, fps)
+}
+
 func nativeH264AvailabilityDetail() string {
 	return ""
 }
@@ -20,3 +24,11 @@ func encodeNativeH264D3D11Texture(device, texture unsafe.Pointer, inputWidth, in
 func requestNativeH264D3D11TextureKeyframe() {}
 
 func resetNativeH264D3D11TextureEncoder() {}
+
+func encodeNativeHEVCD3D11Texture(device, texture unsafe.Pointer, inputWidth, inputHeight, encodeWidth, encodeHeight, fps int, dxgiFormat uint32, forceIDR bool) ([]byte, error) {
+	return nil, fmt.Errorf("native NVENC HEVC D3D11 texture encode requires cgo for input=%dx%d output=%dx%d@%dfps", inputWidth, inputHeight, encodeWidth, encodeHeight, fps)
+}
+
+func requestNativeHEVCD3D11TextureKeyframe() {}
+
+func resetNativeHEVCD3D11TextureEncoder() {}

Overlord-Client/cmd/agent/capture/nvenc_d3d11_smoke_stub.go

@@ -9,11 +9,12 @@ import (
 )
 
 type NVENCD3D11SmokeOptions struct {
-	Width   int `json:"width"`
-	Height  int `json:"height"`
-	FPS     int `json:"fps"`
-	Frames  int `json:"frames"`
-	Bitrate int `json:"bitrate"`
+	Width   int    `json:"width"`
+	Height  int    `json:"height"`
+	FPS     int    `json:"fps"`
+	Frames  int    `json:"frames"`
+	Bitrate int    `json:"bitrate"`
+	Codec   string `json:"codec,omitempty"`
 }
 
 type NVENCD3D11SmokeResult struct {

Overlord-Client/cmd/agent/capture/nvenc_d3d11_smoke_windows.go

@@ -134,6 +134,16 @@ static void nvenc_configure_h264_stream(NV_ENC_CONFIG *cfg, int fps) {
 	cfg->encodeCodecConfig.h264Config.h264VUIParameters.colourMatrix = NV_ENC_VUI_MATRIX_COEFFS_BT709;
 }
 
+static void nvenc_configure_hevc_stream(NV_ENC_CONFIG *cfg, int fps) {
+	(void)fps;
+	cfg->gopLength = NVENC_INFINITE_GOPLENGTH;
+	cfg->frameIntervalP = 1;
+	cfg->encodeCodecConfig.hevcConfig.idrPeriod = NVENC_INFINITE_GOPLENGTH;
+	cfg->encodeCodecConfig.hevcConfig.repeatSPSPPS = 1;
+	cfg->encodeCodecConfig.hevcConfig.level = NV_ENC_LEVEL_HEVC_52;
+	cfg->encodeCodecConfig.hevcConfig.chromaFormatIDC = 1;
+}
+
 static void nvenc_set_video_processor_color_space(nvenc_d3d11_texture_encoder *enc) {
 	D3D11_VIDEO_PROCESSOR_COLOR_SPACE input_space;
 	memset(&input_space, 0, sizeof(input_space));
@@ -287,7 +297,7 @@ static void nvenc_release_texture_encoder(nvenc_d3d11_texture_encoder *enc) {
 	free(enc);
 }
 
-static nvenc_d3d11_texture_create_result nvenc_create_d3d11_texture_encoder(ID3D11Device *device, int input_width, int input_height, int encode_width, int encode_height, int fps, int bitrate, NV_ENC_BUFFER_FORMAT buffer_format, int dxgi_format, int output_mode) {
+static nvenc_d3d11_texture_create_result nvenc_create_d3d11_texture_encoder(ID3D11Device *device, int input_width, int input_height, int encode_width, int encode_height, int fps, int bitrate, NV_ENC_BUFFER_FORMAT buffer_format, int dxgi_format, int output_mode, int codec) {
 	nvenc_d3d11_texture_create_result out;
 	memset(&out, 0, sizeof(out));
 	if (!device) {
@@ -374,7 +384,8 @@ static nvenc_d3d11_texture_create_result nvenc_create_d3d11_texture_encoder(ID3D
 	memset(&preset, 0, sizeof(preset));
 	preset.version = NV_ENC_PRESET_CONFIG_VER;
 	preset.presetCfg.version = NV_ENC_CONFIG_VER;
-	status = enc->api.nvEncGetEncodePresetConfigEx(enc->encoder, NV_ENC_CODEC_H264_GUID, NV_ENC_PRESET_P1_GUID, NV_ENC_TUNING_INFO_ULTRA_LOW_LATENCY, &preset);
+	GUID codec_guid = codec == 1 ? NV_ENC_CODEC_HEVC_GUID : NV_ENC_CODEC_H264_GUID;
+	status = enc->api.nvEncGetEncodePresetConfigEx(enc->encoder, codec_guid, NV_ENC_PRESET_P1_GUID, NV_ENC_TUNING_INFO_ULTRA_LOW_LATENCY, &preset);
 	if (status != NV_ENC_SUCCESS) {
 		out.stage = 9;
 		out.nvstatus = status;
@@ -382,18 +393,22 @@ static nvenc_d3d11_texture_create_result nvenc_create_d3d11_texture_encoder(ID3D
 		nvenc_release_texture_encoder(enc);
 		return out;
 	}
-	preset.presetCfg.profileGUID = NV_ENC_H264_PROFILE_HIGH_GUID;
+	preset.presetCfg.profileGUID = codec == 1 ? NV_ENC_HEVC_PROFILE_MAIN_GUID : NV_ENC_H264_PROFILE_HIGH_GUID;
 	preset.presetCfg.rcParams.rateControlMode = NV_ENC_PARAMS_RC_CBR;
 	preset.presetCfg.rcParams.averageBitRate = (uint32_t)bitrate;
 	preset.presetCfg.rcParams.maxBitRate = (uint32_t)bitrate;
 	preset.presetCfg.rcParams.vbvBufferSize = (uint32_t)(bitrate / fps);
 	preset.presetCfg.rcParams.vbvInitialDelay = (uint32_t)(bitrate / fps);
-	nvenc_configure_h264_stream(&preset.presetCfg, fps);
+	if (codec == 1) {
+		nvenc_configure_hevc_stream(&preset.presetCfg, fps);
+	} else {
+		nvenc_configure_h264_stream(&preset.presetCfg, fps);
+	}
 
 	NV_ENC_INITIALIZE_PARAMS init;
 	memset(&init, 0, sizeof(init));
 	init.version = NV_ENC_INITIALIZE_PARAMS_VER;
-	init.encodeGUID = NV_ENC_CODEC_H264_GUID;
+	init.encodeGUID = codec_guid;
 	init.presetGUID = NV_ENC_PRESET_P1_GUID;
 	init.encodeWidth = (uint32_t)encode_width;
 	init.encodeHeight = (uint32_t)encode_height;
@@ -594,13 +609,13 @@ static nvenc_d3d11_texture_create_result nvenc_create_d3d11_texture_encoder(ID3D
 	return out;
 }
 
-static nvenc_d3d11_create_result nvenc_create_d3d11_encoder(int width, int height, int fps, int bitrate) {
+static nvenc_d3d11_create_result nvenc_create_d3d11_encoder(int width, int height, int fps, int bitrate, int codec) {
 	nvenc_d3d11_create_result out;
 	memset(&out, 0, sizeof(out));
-	if (width <= 0 || height <= 0 || (width & 1) || (height & 1) || fps <= 0) {
+	if (width <= 0 || height <= 0 || (width & 1) || (height & 1) || fps <= 0 || (codec != 0 && codec != 1)) {
 		out.stage = 1;
 		out.nvstatus = NV_ENC_ERR_INVALID_PARAM;
-		strncpy(out.message, "width/height/fps must be positive, and width/height must be even", sizeof(out.message)-1);
+		strncpy(out.message, "invalid width/height/fps or codec", sizeof(out.message)-1);
 		return out;
 	}
 
@@ -679,7 +694,8 @@ static nvenc_d3d11_create_result nvenc_create_d3d11_encoder(int width, int heigh
 	memset(&preset, 0, sizeof(preset));
 	preset.version = NV_ENC_PRESET_CONFIG_VER;
 	preset.presetCfg.version = NV_ENC_CONFIG_VER;
-	status = enc->api.nvEncGetEncodePresetConfigEx(enc->encoder, NV_ENC_CODEC_H264_GUID, NV_ENC_PRESET_P1_GUID, NV_ENC_TUNING_INFO_ULTRA_LOW_LATENCY, &preset);
+	GUID codec_guid = codec == 1 ? NV_ENC_CODEC_HEVC_GUID : NV_ENC_CODEC_H264_GUID;
+	status = enc->api.nvEncGetEncodePresetConfigEx(enc->encoder, codec_guid, NV_ENC_PRESET_P1_GUID, NV_ENC_TUNING_INFO_ULTRA_LOW_LATENCY, &preset);
 	if (status != NV_ENC_SUCCESS) {
 		out.stage = 8;
 		out.nvstatus = status;
@@ -687,18 +703,22 @@ static nvenc_d3d11_create_result nvenc_create_d3d11_encoder(int width, int heigh
 		nvenc_release_encoder(enc);
 		return out;
 	}
-	preset.presetCfg.profileGUID = NV_ENC_H264_PROFILE_HIGH_GUID;
+	preset.presetCfg.profileGUID = codec == 1 ? NV_ENC_HEVC_PROFILE_MAIN_GUID : NV_ENC_H264_PROFILE_HIGH_GUID;
 	preset.presetCfg.rcParams.rateControlMode = NV_ENC_PARAMS_RC_CBR;
 	preset.presetCfg.rcParams.averageBitRate = (uint32_t)bitrate;
 	preset.presetCfg.rcParams.maxBitRate = (uint32_t)bitrate;
 	preset.presetCfg.rcParams.vbvBufferSize = (uint32_t)(bitrate / fps);
 	preset.presetCfg.rcParams.vbvInitialDelay = (uint32_t)(bitrate / fps);
-	nvenc_configure_h264_stream(&preset.presetCfg, fps);
+	if (codec == 1) {
+		nvenc_configure_hevc_stream(&preset.presetCfg, fps);
+	} else {
+		nvenc_configure_h264_stream(&preset.presetCfg, fps);
+	}
 
 	NV_ENC_INITIALIZE_PARAMS init;
 	memset(&init, 0, sizeof(init));
 	init.version = NV_ENC_INITIALIZE_PARAMS_VER;
-	init.encodeGUID = NV_ENC_CODEC_H264_GUID;
+	init.encodeGUID = codec_guid;
 	init.presetGUID = NV_ENC_PRESET_P1_GUID;
 	init.encodeWidth = (uint32_t)width;
 	init.encodeHeight = (uint32_t)height;
@@ -1325,7 +1345,7 @@ static nvenc_d3d11_smoke_result run_nvenc_d3d11_smoke_c(int width, int height, i
 	return out;
 }
 
-static nvenc_d3d11_smoke_result run_nvenc_d3d11_texture_pipeline_smoke_c(int width, int height, int fps, int frames, int bitrate) {
+static nvenc_d3d11_smoke_result run_nvenc_d3d11_texture_pipeline_smoke_c(int width, int height, int fps, int frames, int bitrate, int codec) {
 	nvenc_d3d11_smoke_result out;
 	memset(&out, 0, sizeof(out));
 	out.width = width;
@@ -1391,7 +1411,7 @@ static nvenc_d3d11_smoke_result run_nvenc_d3d11_texture_pipeline_smoke_c(int wid
 		return out;
 	}
 
-	nvenc_d3d11_texture_create_result created = nvenc_create_d3d11_texture_encoder(device, width, height, width, height, fps, bitrate, NV_ENC_BUFFER_FORMAT_ARGB, DXGI_FORMAT_B8G8R8A8_UNORM, 0);
+	nvenc_d3d11_texture_create_result created = nvenc_create_d3d11_texture_encoder(device, width, height, width, height, fps, bitrate, NV_ENC_BUFFER_FORMAT_ARGB, DXGI_FORMAT_B8G8R8A8_UNORM, 0, codec);
 	if (!created.encoder) {
 		out.stage = 5;
 		out.hr = created.hr;
@@ -1467,11 +1487,12 @@ import (
 )
 
 type NVENCD3D11SmokeOptions struct {
-	Width   int `json:"width"`
-	Height  int `json:"height"`
-	FPS     int `json:"fps"`
-	Frames  int `json:"frames"`
-	Bitrate int `json:"bitrate"`
+	Width   int    `json:"width"`
+	Height  int    `json:"height"`
+	FPS     int    `json:"fps"`
+	Frames  int    `json:"frames"`
+	Bitrate int    `json:"bitrate"`
+	Codec   string `json:"codec,omitempty"`
 }
 
 type NVENCD3D11SmokeResult struct {
@@ -1505,8 +1526,15 @@ func RunNVENCD3D11Smoke(opts NVENCD3D11SmokeOptions) NVENCD3D11SmokeResult {
 	}
 	if opts.Bitrate <= 0 {
 		opts.Bitrate = targetH264Bitrate(opts.Width, opts.Height, opts.FPS)
+		if strings.EqualFold(opts.Codec, "hevc") || strings.EqualFold(opts.Codec, "h265") {
+			opts.Bitrate = opts.Bitrate * 7 / 10
+		}
 	}
-	raw := C.run_nvenc_d3d11_texture_pipeline_smoke_c(C.int(opts.Width), C.int(opts.Height), C.int(opts.FPS), C.int(opts.Frames), C.int(opts.Bitrate))
+	codec := 0
+	if strings.EqualFold(opts.Codec, "hevc") || strings.EqualFold(opts.Codec, "h265") {
+		codec = 1
+	}
+	raw := C.run_nvenc_d3d11_texture_pipeline_smoke_c(C.int(opts.Width), C.int(opts.Height), C.int(opts.FPS), C.int(opts.Frames), C.int(opts.Bitrate), C.int(codec))
 	result := NVENCD3D11SmokeResult{
 		OK:         raw.ok != 0,
 		Width:      int(raw.width),
@@ -1545,7 +1573,7 @@ type nativeH264Encoder struct {
 
 func newNativeH264Encoder(stream string, width, height, fps int) (h264FrameEncoder, error) {
 	bitrate := targetH264Bitrate(width, height, fps)
-	raw := C.nvenc_create_d3d11_encoder(C.int(width), C.int(height), C.int(fps), C.int(bitrate))
+	raw := C.nvenc_create_d3d11_encoder(C.int(width), C.int(height), C.int(fps), C.int(bitrate), 0)
 	if raw.encoder == nil {
 		return nil, formatNVENCCreateError(raw)
 	}
@@ -1560,6 +1588,23 @@ func newNativeH264Encoder(stream string, width, height, fps int) (h264FrameEncod
 	return enc, nil
 }
 
+func newNativeHEVCEncoder(stream string, width, height, fps int) (h264FrameEncoder, error) {
+	bitrate := targetH264Bitrate(width, height, fps) * 7 / 10
+	raw := C.nvenc_create_d3d11_encoder(C.int(width), C.int(height), C.int(fps), C.int(bitrate), 1)
+	if raw.encoder == nil {
+		return nil, formatNVENCCreateError(raw)
+	}
+	enc := &nativeH264Encoder{
+		enc:          raw.encoder,
+		width:        width,
+		height:       height,
+		requestedFPS: fps,
+		fps:          fps,
+	}
+	log.Printf("capture: native NVENC D3D11 hevc encoder active stream=%s provider=NVIDIA NVENC size=%dx%d fps=%d input=NV12(upload) bitrate=%d", stream, width, height, fps, bitrate)
+	return enc, nil
+}
+
 func nativeH264AvailabilityDetail() string {
 	probe := RunNVENCSmoke()
 	if probe.Available {
@@ -1645,15 +1690,26 @@ type nativeD3D11TextureH264Encoder struct {
 	outputName   string
 	frame        uint64
 	slowLogs     int
+	codec        string
 }
 
 func newNativeD3D11TextureH264Encoder(device unsafe.Pointer, inputWidth, inputHeight, encodeWidth, encodeHeight, fps int, dxgiFormat uint32) (*nativeD3D11TextureH264Encoder, error) {
+	return newNativeD3D11TextureEncoder(device, inputWidth, inputHeight, encodeWidth, encodeHeight, fps, dxgiFormat, "h264")
+}
+
+func newNativeD3D11TextureEncoder(device unsafe.Pointer, inputWidth, inputHeight, encodeWidth, encodeHeight, fps int, dxgiFormat uint32, codec string) (*nativeD3D11TextureH264Encoder, error) {
 	bufferFormat, name, ok := nvencBufferFormatForDXGI(dxgiFormat)
 	if !ok {
 		return nil, fmt.Errorf("unsupported DXGI texture format %d", dxgiFormat)
 	}
 	bitrate := targetH264Bitrate(encodeWidth, encodeHeight, fps)
 	modes := preferredNVENCD3D11OutputModes()
+	codecID := 0
+	if codec == "hevc" {
+		codecID = 1
+		bitrate = bitrate * 7 / 10
+		modes = []int{0}
+	}
 	var lastErr error
 	var raw C.nvenc_d3d11_texture_create_result
 	outputMode := 0
@@ -1670,6 +1726,7 @@ func newNativeD3D11TextureH264Encoder(device unsafe.Pointer, inputWidth, inputHe
 			C.NV_ENC_BUFFER_FORMAT(bufferFormat),
 			C.int(dxgiFormat),
 			C.int(mode),
+			C.int(codecID),
 		)
 		if raw.encoder != nil {
 			outputMode = mode
@@ -1703,11 +1760,12 @@ func newNativeD3D11TextureH264Encoder(device unsafe.Pointer, inputWidth, inputHe
 		bufferFormat: uint32(bufferFormat),
 		outputMode:   outputMode,
 		outputName:   outputName,
+		codec:        codec,
 	}
 	if inputWidth != encodeWidth || inputHeight != encodeHeight {
-		log.Printf("capture: native NVENC D3D11 desktop texture encoder active provider=NVIDIA NVENC input=%dx%d output=%dx%d fps=%d source_format=%s(dxgi=%d) nvenc_input=%s pipeline=%s bitrate=%d", inputWidth, inputHeight, encodeWidth, encodeHeight, fps, name, dxgiFormat, outputName, pipeline, bitrate)
+		log.Printf("capture: native NVENC D3D11 desktop texture encoder active codec=%s provider=NVIDIA NVENC input=%dx%d output=%dx%d fps=%d source_format=%s(dxgi=%d) nvenc_input=%s pipeline=%s bitrate=%d", codec, inputWidth, inputHeight, encodeWidth, encodeHeight, fps, name, dxgiFormat, outputName, pipeline, bitrate)
 	} else {
-		log.Printf("capture: native NVENC D3D11 desktop texture encoder active provider=NVIDIA NVENC size=%dx%d fps=%d source_format=%s(dxgi=%d) nvenc_input=%s pipeline=%s bitrate=%d", encodeWidth, encodeHeight, fps, name, dxgiFormat, outputName, pipeline, bitrate)
+		log.Printf("capture: native NVENC D3D11 desktop texture encoder active codec=%s provider=NVIDIA NVENC size=%dx%d fps=%d source_format=%s(dxgi=%d) nvenc_input=%s pipeline=%s bitrate=%d", codec, encodeWidth, encodeHeight, fps, name, dxgiFormat, outputName, pipeline, bitrate)
 	}
 	return enc, nil
 }
@@ -1867,6 +1925,9 @@ var (
 	nativeTextureH264Mu       sync.Mutex
 	nativeTextureH264Enc      *nativeD3D11TextureH264Encoder
 	nativeTextureH264ForceIDR atomic.Bool
+	nativeTextureHEVCMu       sync.Mutex
+	nativeTextureHEVCEnc      *nativeD3D11TextureH264Encoder
+	nativeTextureHEVCForceIDR atomic.Bool
 )
 
 func encodeNativeH264D3D11Texture(device, texture unsafe.Pointer, inputWidth, inputHeight, encodeWidth, encodeHeight, fps int, dxgiFormat uint32, forceIDR bool) ([]byte, error) {
@@ -1903,3 +1964,38 @@ func resetNativeH264D3D11TextureEncoder() {
 	}
 	nativeTextureH264ForceIDR.Store(false)
 }
+
+func encodeNativeHEVCD3D11Texture(device, texture unsafe.Pointer, inputWidth, inputHeight, encodeWidth, encodeHeight, fps int, dxgiFormat uint32, forceIDR bool) ([]byte, error) {
+	if device == nil || texture == nil {
+		return nil, fmt.Errorf("nil D3D11 device or texture")
+	}
+	nativeTextureHEVCMu.Lock()
+	defer nativeTextureHEVCMu.Unlock()
+
+	if nativeTextureHEVCEnc == nil || !nativeTextureHEVCEnc.Matches(device, inputWidth, inputHeight, encodeWidth, encodeHeight, fps, dxgiFormat) {
+		if nativeTextureHEVCEnc != nil {
+			nativeTextureHEVCEnc.Close()
+			nativeTextureHEVCEnc = nil
+		}
+		enc, err := newNativeD3D11TextureEncoder(device, inputWidth, inputHeight, encodeWidth, encodeHeight, fps, dxgiFormat, "hevc")
+		if err != nil {
+			return nil, err
+		}
+		nativeTextureHEVCEnc = enc
+	}
+	return nativeTextureHEVCEnc.EncodeTexture(texture, forceIDR || nativeTextureHEVCForceIDR.Swap(false))
+}
+
+func requestNativeHEVCD3D11TextureKeyframe() {
+	nativeTextureHEVCForceIDR.Store(true)
+}
+
+func resetNativeHEVCD3D11TextureEncoder() {
+	nativeTextureHEVCMu.Lock()
+	defer nativeTextureHEVCMu.Unlock()
+	if nativeTextureHEVCEnc != nil {
+		nativeTextureHEVCEnc.Close()
+		nativeTextureHEVCEnc = nil
+	}
+	nativeTextureHEVCForceIDR.Store(false)
+}

Overlord-Client/cmd/agent/capture/win_duplication.go

@@ -661,7 +661,11 @@ func captureDisplayDXGI(display int) (*image.RGBA, error) {
 }
 
 func captureDisplayDXGIH264(display int, forceKeyframe bool) ([]byte, int, int, time.Duration, time.Duration, bool, error) {
-	return dxgiState.captureH264(display, forceKeyframe)
+	return dxgiState.captureVideo(display, "h264", forceKeyframe)
+}
+
+func captureDisplayDXGIHEVC(display int, forceKeyframe bool) ([]byte, int, int, time.Duration, time.Duration, bool, error) {
+	return dxgiState.captureVideo(display, "hevc", forceKeyframe)
 }
 
 func (s *duplicationState) reset() {
@@ -685,6 +689,7 @@ func (s *duplicationState) closeLocked() {
 		s.h264LastDesc = d3d11Texture2DDesc{}
 	}
 	resetH264D3D11TextureEncoder()
+	resetNativeHEVCD3D11TextureEncoder()
 	if s.context != nil {
 		s.context.Release()
 		s.context = nil
@@ -875,13 +880,13 @@ func (s *duplicationState) copyLastBaseLocked(src *image.RGBA) {
 	s.lastBase = cloneRGBA(src)
 }
 
-func (s *duplicationState) captureH264(display int, forceKeyframe bool) ([]byte, int, int, time.Duration, time.Duration, bool, error) {
+func (s *duplicationState) captureVideo(display int, codec string, forceKeyframe bool) ([]byte, int, int, time.Duration, time.Duration, bool, error) {
 	capStart := time.Now()
 	s.mu.Lock()
 	defer s.mu.Unlock()
 
 	if !useDesktopDuplication() || cursorCaptureEnabled.Load() {
-		return nil, 0, 0, 0, 0, false, errors.New("direct h264 requires DXGI duplication and cursor capture disabled")
+		return nil, 0, 0, 0, 0, false, fmt.Errorf("direct %s requires DXGI duplication and cursor capture disabled", codec)
 	}
 	if err := s.ensure(display); err != nil {
 		s.lastFail = time.Now()
@@ -891,10 +896,10 @@ func (s *duplicationState) captureH264(display int, forceKeyframe bool) ([]byte,
 	width := int(s.desc.ModeDesc.Width)
 	height := int(s.desc.ModeDesc.Height)
 	if width <= 0 || height <= 0 || width%2 != 0 || height%2 != 0 {
-		return nil, 0, 0, 0, 0, false, fmt.Errorf("direct h264 requires positive even dimensions, got %dx%d", width, height)
+		return nil, 0, 0, 0, 0, false, fmt.Errorf("direct %s requires positive even dimensions, got %dx%d", codec, width, height)
 	}
 	if s.desc.Rotation != dxgiModeRotationIdentity && s.desc.Rotation != dxgiModeRotationUnspecified {
-		return nil, 0, 0, 0, 0, false, fmt.Errorf("direct h264 requires identity rotation, got %d", s.desc.Rotation)
+		return nil, 0, 0, 0, 0, false, fmt.Errorf("direct %s requires identity rotation, got %d", codec, s.desc.Rotation)
 	}
 	encodeW, encodeH := width, height
 	if scale := effectiveScale(width, height); scale != 1 {
@@ -906,7 +911,7 @@ func (s *duplicationState) captureH264(display int, forceKeyframe bool) ([]byte,
 			return nil, 0, 0, 0, 0, false, fmt.Errorf("direct h264 computed invalid scaled output %dx%d", encodeW, encodeH)
 		}
 		directH264ScaleOnce.Do(func() {
-			log.Printf("capture: direct DXGI hardware h264 scaling enabled scale=%.2f input=%dx%d output=%dx%d", scale, width, height, encodeW, encodeH)
+			log.Printf("capture: direct DXGI hardware %s scaling enabled scale=%.2f input=%dx%d output=%dx%d", codec, scale, width, height, encodeW, encodeH)
 		})
 	}
 
@@ -918,7 +923,7 @@ func (s *duplicationState) captureH264(display int, forceKeyframe bool) ([]byte,
 			captureDur := time.Since(capStart)
 			fps := activeH264FPS()
 			encStart := time.Now()
-			out, _, err := encodeH264D3D11Texture(h264D3D11TextureRequest{
+			out, _, err := encodeDesktopD3D11Texture(codec, h264D3D11TextureRequest{
 				Device: unsafe.Pointer(s.device), Texture: unsafe.Pointer(s.h264LastTex),
 				InputWidth: width, InputHeight: height, EncodeWidth: encodeW, EncodeHeight: encodeH,
 				FPS: fps, DXGIFormat: s.h264LastDesc.Format, ForceIDR: forceKeyframe,
@@ -926,7 +931,7 @@ func (s *duplicationState) captureH264(display int, forceKeyframe bool) ([]byte,
 			encodeDur := time.Since(encStart)
 			if err != nil {
 				directH264WarnOnce.Do(func() {
-					log.Printf("capture: direct DXGI hardware h264 cached-frame encode failed for %dx%d@%dfps format=%d: %v; using readback path", width, height, fps, s.h264LastDesc.Format, err)
+					log.Printf("capture: direct DXGI hardware %s cached-frame encode failed for %dx%d@%dfps format=%d: %v; using readback path", codec, width, height, fps, s.h264LastDesc.Format, err)
 				})
 				return nil, 0, 0, 0, 0, false, err
 			}
@@ -978,13 +983,13 @@ func (s *duplicationState) captureH264(display int, forceKeyframe bool) ([]byte,
 	}
 	if srcDesc.Format != dxgiFormatB8G8R8A8UNorm && srcDesc.Format != dxgiFormatR8G8B8A8UNorm {
 		directH264WarnOnce.Do(func() {
-			log.Printf("capture: direct DXGI hardware h264 unavailable: unsupported DXGI texture format %d; using readback path", srcDesc.Format)
+			log.Printf("capture: direct DXGI hardware %s unavailable: unsupported DXGI texture format %d; using readback path", codec, srcDesc.Format)
 		})
-		return nil, 0, 0, 0, 0, false, fmt.Errorf("direct h264 unsupported DXGI texture format %d", srcDesc.Format)
+		return nil, 0, 0, 0, 0, false, fmt.Errorf("direct %s unsupported DXGI texture format %d", codec, srcDesc.Format)
 	}
 	if err := s.cacheH264TextureLocked(tex, srcDesc); err != nil {
 		directH264WarnOnce.Do(func() {
-			log.Printf("capture: direct DXGI hardware h264 cache setup failed for %dx%d format=%d: %v; using readback path", width, height, srcDesc.Format, err)
+			log.Printf("capture: direct DXGI hardware %s cache setup failed for %dx%d format=%d: %v; using readback path", codec, width, height, srcDesc.Format, err)
 		})
 		return nil, 0, 0, 0, 0, false, err
 	}
@@ -995,7 +1000,7 @@ func (s *duplicationState) captureH264(display int, forceKeyframe bool) ([]byte,
 
 	fps := activeH264FPS()
 	encStart := time.Now()
-	out, provider, err := encodeH264D3D11Texture(h264D3D11TextureRequest{
+	out, provider, err := encodeDesktopD3D11Texture(codec, h264D3D11TextureRequest{
 		Device: unsafe.Pointer(s.device), Texture: unsafe.Pointer(s.h264LastTex),
 		InputWidth: width, InputHeight: height, EncodeWidth: encodeW, EncodeHeight: encodeH,
 		FPS: fps, DXGIFormat: s.h264LastDesc.Format, ForceIDR: forceKeyframe,
@@ -1003,7 +1008,7 @@ func (s *duplicationState) captureH264(display int, forceKeyframe bool) ([]byte,
 	encodeDur := time.Since(encStart)
 	if err != nil {
 		directH264WarnOnce.Do(func() {
-			log.Printf("capture: direct DXGI hardware h264 failed for %dx%d@%dfps format=%d: %v; using readback path", width, height, fps, s.h264LastDesc.Format, err)
+			log.Printf("capture: direct DXGI hardware %s failed for %dx%d@%dfps format=%d: %v; using readback path", codec, width, height, fps, s.h264LastDesc.Format, err)
 		})
 		return nil, 0, 0, 0, 0, false, err
 	}
@@ -1011,11 +1016,20 @@ func (s *duplicationState) captureH264(display int, forceKeyframe bool) ([]byte,
 		return nil, encodeW, encodeH, captureDur, encodeDur, true, nil
 	}
 	directH264ActiveOnce.Do(func() {
-		log.Printf("capture: direct DXGI hardware h264 path active provider=%q input=%dx%d output=%dx%d fps=%d dxgi_format=%d", provider, width, height, encodeW, encodeH, fps, srcDesc.Format)
+		log.Printf("capture: direct DXGI hardware %s path active provider=%q input=%dx%d output=%dx%d fps=%d dxgi_format=%d", codec, provider, width, height, encodeW, encodeH, fps, srcDesc.Format)
 	})
 	return out, encodeW, encodeH, captureDur, encodeDur, true, nil
 }
 
+func encodeDesktopD3D11Texture(codec string, req h264D3D11TextureRequest) ([]byte, string, error) {
+	if codec == "hevc" {
+		out, err := encodeNativeHEVCD3D11Texture(req.Device, req.Texture, req.InputWidth, req.InputHeight,
+			req.EncodeWidth, req.EncodeHeight, req.FPS, req.DXGIFormat, req.ForceIDR)
+		return out, "NVIDIA NVENC", err
+	}
+	return encodeH264D3D11Texture(req)
+}
+
 func (s *duplicationState) cacheH264TextureLocked(src *d3d11Texture2D, srcDesc d3d11Texture2DDesc) error {
 	if src == nil || s.device == nil || s.context == nil {
 		return errors.New("nil D3D11 source/device/context")

Overlord-Client/cmd/agent/handlers/command.go

@@ -889,9 +889,16 @@ func HandleCommand(ctx context.Context, env *runtime.Env, envelope map[string]in
 					FPS: profile.FPS, Label: profile.Label, Providers: profile.Providers,
 				})
 			}
+			codecs := make([]wire.DesktopCodecCapability, 0, len(caps.Codecs))
+			for _, codec := range caps.Codecs {
+				codecs = append(codecs, wire.DesktopCodecCapability{
+					Codec: codec.Codec, Encoders: codec.Encoders,
+					Transports: codec.Transports, Hardware: codec.Hardware,
+				})
+			}
 			if err := wire.WriteMsg(ctx, env.Conn, wire.DesktopEncoderCapabilities{
 				Type: "desktop_encoder_capabilities", CommandID: cmdID, Probed: caps.Probed,
-				Display: caps.Display, Profiles: profiles, Detail: caps.Detail,
+				Display: caps.Display, Profiles: profiles, Codecs: codecs, Detail: caps.Detail,
 			}); err != nil {
 				log.Printf("desktop: encoder capability result send failed: %v", err)
 			}

Overlord-Client/cmd/agent/wire/protocol.go

@@ -78,13 +78,21 @@ type DesktopEncoderProfile struct {
 	Providers []string `msgpack:"providers"`
 }
 
+type DesktopCodecCapability struct {
+	Codec      string   `msgpack:"codec"`
+	Encoders   []string `msgpack:"encoders,omitempty"`
+	Transports []string `msgpack:"transports"`
+	Hardware   bool     `msgpack:"hardware,omitempty"`
+}
+
 type DesktopEncoderCapabilities struct {
-	Type      string                  `msgpack:"type"`
-	CommandID string                  `msgpack:"commandId,omitempty"`
-	Probed    bool                    `msgpack:"probed"`
-	Display   int                     `msgpack:"display"`
-	Profiles  []DesktopEncoderProfile `msgpack:"profiles"`
-	Detail    string                  `msgpack:"detail,omitempty"`
+	Type      string                   `msgpack:"type"`
+	CommandID string                   `msgpack:"commandId,omitempty"`
+	Probed    bool                     `msgpack:"probed"`
+	Display   int                      `msgpack:"display"`
+	Profiles  []DesktopEncoderProfile  `msgpack:"profiles"`
+	Codecs    []DesktopCodecCapability `msgpack:"codecs"`
+	Detail    string                   `msgpack:"detail,omitempty"`
 }
 
 type ClientLogEntry struct {