forked from unom/punktfunk
enricobuehler
6d0a389dd2
The follow-up was framed as "build the frame-hash parity harness the D3D11VA AV1 rung is missing, then flip hardware_verified to true". Both halves were wrong. The harness was never missing. `video_d3d11_native`'s `parity` module has carried `av1_every_delivered_frame_hashes_bit_identical_to_libavcodec` since M7 wired the rung — wired to the SAME libavcodec goldens the Vulkan AV1 leg passes against, with the display-order model that handles the vector's 24 hidden frames, sitting `#[ignore]`d beside the H.264/H.265/Main10 legs. It had simply never been run on a device; .173 was powered off the day it was written. What the old evidence note called a missing harness is real about pf-dxvadec the CRATE, which cannot host one — it links no D3D11 — but the device half lives here and was already done. Run on .221, it FAILS, on both GPUs, deterministically (three runs each, identical first-divergent frame and identical hashes): 186/250 diverging display frames on an RTX 3500 Ada, 245/250 on an Intel Arc. It is the decode that is wrong, not the measurement, and three independent checks say so. H.264 and H.265 pass 250/250 and HEVC Main 10 50/50 through the same harness, the same readback geometry, the same crop and the same slot map on those same two GPUs. pf-vkdecode's Vulkan AV1 leg reproduces the same golden file 250/250 on the same box. And the goldens regenerate byte-for-byte from the ffmpeg build their own header names. Two signatures, and they are not one defect wearing two faces. NVIDIA is bit-exact for display frames 0..=63 and then loses ONE 16x24 luma block — 174 pixels, max |delta| 8, chroma untouched — on the frame whose order_hint first reaches 64, after which every remaining frame is downstream of it through prediction. The stream parks the key frame (order_hint 0) in BWDREF and ALTREF2 for its whole length, so 64 is where the distance to it reaches the edge of what get_relative_dist can represent at OrderHintBits = 7. Intel is structurally wrong from display frame 4 — 47% of luma, max |delta| 242, chroma wrong too, a frame predicted from the wrong picture — and the only later frame it gets right is the one whose primary_ref_frame is PRIMARY_REF_NONE. None of this is visible on glass, which is the whole argument for goldens: the rung streams 4K60 on both parts with a clean five-minute soak at roughly ten times the Vulkan leg's decode time. The 2026-08-07 field sessions that looked clean were looking at wrong pixels. So hardware_verified stays false, and the note now says why in the strongest available terms — it prints at warn on every session that lands here, and "decodes AV1 to wrong pixels" is what a support engineer needs to read. The pair stays in `every_rung_runs_and_the_unproven_ones_are_named`'s unproven array; its note still contains NEVER, because the pair has never PASSED parity, which is now a measured statement rather than an absence. Left deliberately unchanged: `auto` on Windows can still reach this rung for AV1, and on Intel it is the arm that fires, because that vendor advertises no SAMPLED usage on any decode profile so zero-copy Vulkan Video cannot run there. Barring it trades visibly-wrong AV1 for the software rung, which cannot keep up at 4K and is itself unproven. Which way that trade goes is a product call, so it is recorded at the admission site rather than made silently here. `av1_divergence_map` is kept, cleaned up and documented: it is what turned "186 frames differ" into a lead — one line per display frame, its verdict beside the plan facts that could explain it, and an opt-in raw-NV12 dump. At a frame where one vendor hashes correctly, that vendor's bytes ARE libavcodec's bytes and so a valid reference for the other's, which is how "how badly" was answered without new goldens. The tool that would localise the rest does not exist: pf-dxvadec's libav_picparams_parity covers H.264 and HEVC only, so the AV1 conversion has never been compared against libavcodec at the picture-parameter level either. That is the next step, not another session. Also in this file, since it is the same table and the same day: the VAAPI rung's AV1 leg has now decoded 250/250 of the vendored vector on RDNA3 and its arm is split from the H.264/H.265 ones, which genuinely have still never decoded anything. It is unverified for the same reason as ever — no parity — and the D3D11VA row above is exactly why that distinction is worth keeping: a rung can decode 250 frames and still be wrong.