diff --git a/crates/compositor/src/cpu_frames_windows.rs b/crates/compositor/src/cpu_frames_windows.rs
index ea0e921fb..b5a240bbe 100644
--- a/crates/compositor/src/cpu_frames_windows.rs
+++ b/crates/compositor/src/cpu_frames_windows.rs
@@ -24,9 +24,9 @@ use windows::Win32::Graphics::Dxgi::Common::{DXGI_FORMAT_NV12, DXGI_SAMPLE_DESC}
 
 /// Le flag d'algorithme de swscale. Bindgen ne génère pas les `SWS_*` d'algorithme (des
 /// macros), et leurs valeurs sont figées par l'ABI de libswscale. `POINT` (plus proche
-/// voisin) est le choix honnête : la conversion se fait à dimensions ÉGALES, donc aucun
-/// rééchantillonnage n'a lieu — seul le convertisseur de format travaille, et le filtre
-/// choisi n'a aucun effet sur la sortie.
+/// voisin) est le choix honnête : la conversion se fait à dimensions ÉGALES, donc la luma
+/// n'est jamais rééchantillonnée. Seule exception : une source 4:2:2 ou 4:4:4 (H.264
+/// importé) perd sa chroma pleine en passant en NV12, et POINT la décime par voisin.
 const SWS_POINT: i32 = 0x10;
 
 /// Source de frames du backend CPU, attachée à un `Decoder` quand `Backend::Cpu`.
diff --git a/crates/compositor/src/pipeline_windows.rs b/crates/compositor/src/pipeline_windows.rs
index ea6e658b3..4c59cf73c 100644
--- a/crates/compositor/src/pipeline_windows.rs
+++ b/crates/compositor/src/pipeline_windows.rs
@@ -380,6 +380,21 @@ fn d3d11va_for_codec(codec_id: AVCodecID::Type) -> bool {
     codec_id == AVCodecID::AV_CODEC_ID_H264
 }
 
+/// Per-stream refinement of `d3d11va_for_codec`: FFmpeg only offers a D3D11
+/// NV12 surface for 8-bit 4:2:0 H.264. High 10 (yuv420p10le) and 4:2:2 / 4:4:4
+/// get none, `get_hw_format` rejects everything and `send_packet` fails with
+/// AVERROR_INVALIDDATA, so those streams take the software `CpuFrames` path.
+/// An unknown pixel format (`AV_PIX_FMT_NONE`) keeps the hardware path.
+fn d3d11va_for_stream(codec_id: AVCodecID::Type, format: AVPixelFormat::Type) -> bool {
+    d3d11va_for_codec(codec_id)
+        && matches!(
+            format,
+            AVPixelFormat::AV_PIX_FMT_NONE
+                | AVPixelFormat::AV_PIX_FMT_YUV420P
+                | AVPixelFormat::AV_PIX_FMT_YUVJ420P
+        )
+}
+
 unsafe fn require_decoder_id(
     codec_id: AVCodecID::Type,
 ) -> Result<(*const AVCodec, *mut AVCodecContext)> {
@@ -847,10 +862,12 @@ impl Decoder {
         )?;
         allow_d3d11va_h264_baseline(resources.dctx);
 
-        // Hardware D3D11VA is the H.264 capture path. WARP has no video decoder
-        // (`tests/warp_device_cannot_decode.rs`). AV1/VP9 (legacy WebMs, #554)
-        // take the same software CpuFrames axis as Backend::Cpu.
-        let want_hw = gpu.backend != Backend::Cpu && d3d11va_for_codec(codec_id);
+        // Hardware D3D11VA is the H.264 8-bit 4:2:0 capture path. WARP has no video
+        // decoder (`tests/warp_device_cannot_decode.rs`). AV1/VP9 (legacy WebMs, #554)
+        // and H.264 High 10 / 4:2:2 / 4:4:4 (no D3D11 surface exists for them) take
+        // the same software CpuFrames axis as Backend::Cpu.
+        let want_hw = gpu.backend != Backend::Cpu
+            && d3d11va_for_stream(codec_id, (*codecpar).format as AVPixelFormat::Type);
         let cpu = if want_hw {
             None
         } else {
@@ -2168,6 +2185,19 @@ mod tests {
         assert!(!d3d11va_for_codec(AVCodecID::AV_CODEC_ID_VP9));
     }
 
+    #[test]
+    fn d3d11va_is_8bit_420_h264_only() {
+        use AVPixelFormat::*;
+        let h264 = AVCodecID::AV_CODEC_ID_H264;
+        assert!(d3d11va_for_stream(h264, AV_PIX_FMT_YUV420P));
+        assert!(d3d11va_for_stream(h264, AV_PIX_FMT_YUVJ420P));
+        assert!(d3d11va_for_stream(h264, AV_PIX_FMT_NONE));
+        assert!(!d3d11va_for_stream(h264, AV_PIX_FMT_YUV420P10LE));
+        assert!(!d3d11va_for_stream(h264, AV_PIX_FMT_YUV422P));
+        assert!(!d3d11va_for_stream(h264, AV_PIX_FMT_YUV444P));
+        assert!(!d3d11va_for_stream(AVCodecID::AV_CODEC_ID_AV1, AV_PIX_FMT_YUV420P));
+    }
+
     #[test]
     fn require_decoder_rejects_none() {
         let err = unsafe { require_decoder_id(AVCodecID::AV_CODEC_ID_NONE) }