fix(video): honour the client's requested color range

moonshine-core/Cargo.toml

@@ -36,7 +36,7 @@ notify-rust = "4.17.0"
 open = "5.3.5"
 opus = "0.3.1"
 pkcs8 = "0.11.0"
-pixelforge = { git = "https://github.com/hgaiser/pixelforge", tag = "v0.7.2", features = ["dmabuf"] }
+pixelforge = { git = "https://github.com/hgaiser/pixelforge", tag = "v0.8.0", features = ["dmabuf"] }
 pulseaudio = "0.3.1"
 rcgen = "0.14.8"
 rsa = "0.9.10"

moonshine-core/src/rtsp.rs

@@ -360,6 +360,32 @@ impl RtspServer {
 		let max_reference_frames: u32 =
 			get_optional_sdp_attribute(&sdp_session, "x-nv-video[0].maxNumReferenceFrames").unwrap_or(1);
 
+		// Bit 0 selects full-range luma, the remaining bits an SDR colorspace.
+		// Sunshine: `colorspace_from_client_config()`
+		const CSC_COLORSPACE_REC601: u32 = 0;
+		const CSC_COLORSPACE_REC709: u32 = 1;
+		let encoder_csc_mode: Option<u32> = get_optional_sdp_attribute(&sdp_session, "x-nv-video[0].encoderCscMode");
+		let full_range = encoder_csc_mode.unwrap_or_default() & 0x1 != 0;
+
+		// Only Rec.709 is encoded. Rec.601 doubles as the protocol default for
+		// clients that never chose a colorspace, so it stays quiet; higher
+		// values are explicit requests worth a warning.
+		match encoder_csc_mode.map(|mode| mode >> 1) {
+			Some(CSC_COLORSPACE_REC601) => {
+				tracing::debug!("Client sent SDR colorspace Rec.601 (the protocol default), encoding Rec.709.");
+			},
+			Some(colorspace) if colorspace != CSC_COLORSPACE_REC709 => {
+				tracing::warn!(
+					"Client requested SDR colorspace {colorspace} via encoderCscMode, encoding Rec.709 instead."
+				);
+			},
+			_ => {},
+		}
+		tracing::info!(
+			"Client requested {} range video.",
+			if full_range { "full" } else { "limited" }
+		);
+
 		// Parse the client's encryption flags from the ANNOUNCE SDP.
 		let client_encryption_flags: u8 =
 			get_optional_sdp_attribute(&sdp_session, "x-ss-general.encryptionEnabled").unwrap_or(0);
@@ -376,6 +402,7 @@ impl RtspServer {
 			dynamic_range,
 			chroma_sampling_type,
 			max_reference_frames,
+			full_range,
 			encrypt_video: self.video_config.encrypt && (client_encryption_flags & EncryptionFlags::Video as u8 != 0),
 		};
 

moonshine-core/src/session/stream/video/mod.rs

@@ -170,6 +170,10 @@ pub struct VideoStreamContext {
 	/// Maximum number of reference frames for the video encoder.
 	pub max_reference_frames: u32,
 
+	/// Whether the client asked for full-range (0-255) rather than
+	/// limited-range (16-235) luma.
+	pub full_range: bool,
+
 	/// Whether the client has enabled video encryption.
 	pub encrypt_video: bool,
 }

moonshine-core/src/session/stream/video/pipeline/mod.rs

@@ -558,8 +558,8 @@ impl VideoPipelineInner {
 
 		// Select color description for VUI signaling.
 		let color_description = match ctx.dynamic_range {
-			VideoDynamicRange::Sdr => ColorDescription::bt709(),
-			VideoDynamicRange::Hdr => ColorDescription::bt2020_pq(),
+			VideoDynamicRange::Sdr => ColorDescription::bt709().with_full_range(ctx.full_range),
+			VideoDynamicRange::Hdr => ColorDescription::bt2020_pq().with_full_range(ctx.full_range),
 		};
 
 		// Create encode configuration.
@@ -689,8 +689,8 @@ impl VideoPipelineInner {
 		// color_desc differs, we call set_color_description() to update
 		// the SPS/sequence header.
 		let mut encoder_color_desc: Option<ColorDescription> = Some(match ctx.dynamic_range {
-			VideoDynamicRange::Sdr => ColorDescription::bt709(),
-			VideoDynamicRange::Hdr => ColorDescription::bt2020_pq(),
+			VideoDynamicRange::Sdr => ColorDescription::bt709().with_full_range(ctx.full_range),
+			VideoDynamicRange::Hdr => ColorDescription::bt2020_pq().with_full_range(ctx.full_range),
 		});
 
 		while !stop_session_manager.is_shutdown_triggered() {
@@ -780,6 +780,11 @@ impl VideoPipelineInner {
 						match encoder.encode(encoder.input_image()) {
 							Ok(future) => {
 								let submitted_at = std::time::Instant::now();
+								// Deliberately still a whole-struct comparison, unlike the
+								// control-stream check above. Correcting it newly enables
+								// AV1 metadata injection for full-range clients, and that
+								// produces streams Moonlight cannot decode. Left until the
+								// AV1 path is fixed.
 								let inject_hdr = encoder_color_desc == Some(ColorDescription::bt2020_pq());
 								let frame_context = FrameContext {
 									created_at: now,
@@ -919,8 +924,8 @@ impl VideoPipelineInner {
 					Some(conv) => conv,
 					None => {
 						let (color_space, full_range) = match ctx.dynamic_range {
-							VideoDynamicRange::Sdr => (ColorSpace::Bt709, false),
-							VideoDynamicRange::Hdr => (ColorSpace::Bt2020, false),
+							VideoDynamicRange::Sdr => (ColorSpace::Bt709, ctx.full_range),
+							VideoDynamicRange::Hdr => (ColorSpace::Bt2020, ctx.full_range),
 						};
 						let mut config =
 							ColorConverterConfig::new(ctx.width, ctx.height, frame_input_format, output_format);
@@ -951,20 +956,20 @@ impl VideoPipelineInner {
 					let (cs, full_range, color_desc, sdr_white_nits) = match frame_cs {
 						FrameColorSpace::Srgb => (
 							ColorSpace::Bt709,
-							false,
-							ColorDescription::bt709(),
+							ctx.full_range,
+							ColorDescription::bt709().with_full_range(ctx.full_range),
 							BT2408_SDR_REFERENCE_NITS,
 						),
 						FrameColorSpace::Bt2020Pq => (
 							ColorSpace::Bt2020,
-							false,
-							ColorDescription::bt2020_pq(),
+							ctx.full_range,
+							ColorDescription::bt2020_pq().with_full_range(ctx.full_range),
 							BT2408_SDR_REFERENCE_NITS,
 						),
 						FrameColorSpace::ScrgbLinear => (
 							ColorSpace::Bt709LinearToBt2020Pq,
-							false,
-							ColorDescription::bt2020_pq(),
+							ctx.full_range,
+							ColorDescription::bt2020_pq().with_full_range(ctx.full_range),
 							SCRGB_REFERENCE_WHITE_NITS,
 						),
 					};
@@ -1010,7 +1015,7 @@ impl VideoPipelineInner {
 				// In HDR sessions, `enabled` reflects whether the current
 				// frame is encoded as BT.2020+PQ (true) or BT.709 (false).
 				if ctx.dynamic_range == VideoDynamicRange::Hdr {
-					let hdr_enabled = encoder_color_desc == Some(ColorDescription::bt2020_pq());
+					let hdr_enabled = encoder_color_desc.is_some_and(|desc| desc.is_hdr());
 					let new_state = HdrModeState {
 						enabled: hdr_enabled,
 						metadata: frame.hdr_metadata,
@@ -1044,6 +1049,11 @@ impl VideoPipelineInner {
 						// Hand this frame's context plus its packet future to the
 						// consumer thread, which awaits the future, injects HDR SEI if
 						// needed, packetizes and sends it, and records stats.
+						// Deliberately still a whole-struct comparison, unlike the
+						// control-stream check above. Correcting it newly enables
+						// AV1 metadata injection for full-range clients, and that
+						// produces streams Moonlight cannot decode. Left until the
+						// AV1 path is fixed.
 						let inject_hdr = encoder_color_desc == Some(ColorDescription::bt2020_pq());
 						let frame_context = FrameContext {
 							created_at: frame.created_at,

moonshine-tools/src/bin/bench.rs

@@ -597,6 +597,7 @@ async fn run_benchmark(
 		},
 		chroma_sampling_type: VideoChromaSampling::Yuv420,
 		max_reference_frames: 1,
+		full_range: false,
 		encrypt_video: false,
 	};