2 Commits

Author	SHA1	Message	Date
enricobuehler	7649ccb66b	feat(host): native AMF SDK encoder for Windows AMD — drop libavcodec ... Direct-SDK AMF encoder (encode/windows/amf.rs), the AMD analogue of the direct-NVENC path, replacing the libavcodec *_amf dispatch. C-vtable FFI pinned to AMF headers v1.4.36, runtime-loaded from the driver's amfrt64.dll (no build feature, no new dependency) exactly as NVENC loads its DLL. - AVC/HEVC (SDR NV12 + 10-bit HDR P010) and AV1 (RDNA3+, probed); a bounded poll retires the libavcodec ~2-frame output hold; native in-place reset(). - Intra-refresh wave (PUNKTFUNK_INTRA_REFRESH), in-band HDR mastering/CLL metadata (*InHDRMetadata -> HEVC SEI / AV1 OBU), and a native codec probe feeding the GameStream advertisement (windows_backend_is_ffmpeg -> windows_backend_is_probed). - AMD dispatch / advertisement / 4:4:4 are native-only; the libavcodec AMF fallback and the PUNKTFUNK_AMF_FFMPEG hatch are removed. FFmpeg serves QSV only (its AMF path retained solely as the latency A/B comparator). - Overload back-pressure: submit bounds in-flight surfaces below the input ring, draining finished AUs (buffered for poll, FIFO-preserved) to free a slot and retry on AMF_INPUT_FULL instead of tearing the encoder down and forcing an IDR; this also closes a latent ring-overwrite corruption seen under load on-glass. Validated on the lab Ryzen iGPU (AMF runtime 1.4.37): HEVC/AVC across a native reset, HEVC Main10 mastering+CLL SEIs byte-verified, intra-refresh accepted, a backpressure burst FIFO-clean, and end-to-end via the macOS client. Measured §5.2 latency A/B: native encode_us p50 ~5 ms (0.31 frame periods) vs libavcodec ~17 ms (1.01). 4:4:4 stays unsupported (VCN hardware limit). Live-gated tests skip cleanly on non-AMD boxes. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>	2026-07-06 17:33:23 +02:00
enricobuehler	2c1bb4de93	docs(design): native AMF encoder handoff — drop ffmpeg for AMF, keep for QSV ... Design + decision record for replacing the libavcodec *_amf path with a direct AMF SDK encoder (encode/windows/amf.rs, the AMD analogue of the direct NVENC path). Motivation is measured, not speculative: the libavcodec wrapper structurally holds ~2 frames (36 ms p50 at 720p60 on VCN, un-tunable), driver wedges surface as forever-EAGAIN instead of typed AMF_RESULTs, and intra-refresh / in-band HDR SEI are inexpressible through it. Covers the C vtable FFI strategy (amfrt64.dll runtime-load, FFmpeg amfenc.c and OBS texture-amf.cpp as references), bounded-poll retrieval, the property table, watchdog/reset interplay, exact dispatch seams, a lab-iGPU validation plan with today's zero-copy baselines, and three phases ending with the ffmpeg-AMF arm deleted (FFmpeg stays QSV-only). Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>	2026-07-06 14:36:55 +02:00