diff --git a/Makefile b/Makefile
index 95aeae9..c3a5b01 100644
--- a/Makefile
+++ b/Makefile
@@ -1,35 +1,92 @@
-.PHONY: hevc-nvenc x265 av1
+.PHONY: hevc-nvenc x265 x265-master av1 av1-master
 
 FFMPEG=ffmpeg
 IN_FMT=rgba
 
-RESOLUTION=1920x1080
+RESOLUTION=3840x2160
 FPS=60
 OUT=out.mp4
 
-FFMPEG_CMD=$(FFMPEG) -f rawvideo -pix_fmt $(IN_FMT) -s $(RESOLUTION) -framerate $(FPS) -i - -vf "scale=out_color_matrix=bt709:out_range=tv:flags=accurate_rnd+full_chroma_int+bitexact,format=p010le"
+# 10 s GOP: fractal zooms have no scene cuts, so keyframes only cost bits.
+KEYINT=$(shell awk 'BEGIN { print int($(FPS) * 10 + 0.5) }')
+
+FFMPEG_IN=$(FFMPEG) -f rawvideo -pix_fmt $(IN_FMT) -s $(RESOLUTION) -framerate $(FPS) -i -
+SCALE=scale=out_color_matrix=bt709:out_range=tv:flags=accurate_rnd+full_chroma_int+bitexact
+# setparams tags the frames themselves: encoders read colour info from the
+# filter output, so the -color_* options alone left primaries/transfer unset.
+TAG=setparams=colorspace=bt709:color_primaries=bt709:color_trc=bt709:range=tv
+COLOR_TAGS=-colorspace bt709 -color_primaries bt709 -color_trc bt709 -color_range tv
+
+# Settings and CRFs come from tools/encode/ (see its README for the numbers).
+# Tiers: `x265`/`av1` = delivery (VMAF ~95 mean, >= 90 worst frame, smallest
+# file); `*-master` = upload master (>= 97 worst frame, size secondary).
+# The binding test clip is a faint, low-contrast Julia texture: at a CRF where
+# dense filaments already score 99, both encoders smear it, so it sets the CRF.
+
+# preset medium: slow scores better at equal bitrate but runs ~2.4x slower,
+#   far outside the speed budget.
+# aq-mode=3 (vs 4): 4 loses at matched bitrate on gradients and faint texture.
+# no-sao: SAO lowers VMAF at the same bitrate (smooths fine filaments).
+# merange=92: 4K zoom motion is large; ~2% smaller at no speed cost.
+# rect=1: ~7% smaller at equal or better VMAF (about 20% slower).
+# rdoq-level=2 + psy-rdoq=1: keeps the faint texture; the binding clip then
+#   needs CRF ~17 instead of ~15, a smaller file overall.
+X265_PARAMS=keyint=$(KEYINT):min-keyint=$(FPS):aq-mode=3:no-sao=1:merange=92:rect=1:rdoq-level=2:psy-rdoq=1.0
+
+# preset 6: fits the speed budget (p5 is ~20% slower).
+# tune=0 (VQ; ffmpeg defaults to PSNR): much better worst frames on faint texture.
+# enable-variance-boost=1: more bits to flat/low-contrast blocks; faint Julia
+#   texture goes from p1 ~85 to ~93 at CRF 32.
+# enable-qm=1 (default qm-min): 3-11% smaller at equal VMAF; qm-min=0 caps
+#   quality on faint texture and hurts filaments.
+# film-grain=0: synthetic grain would add noise the renders don't have.
+# tf and overlays stay default: disabling tf costs +50% bits and adds banding.
+# scd=1: untested on its own; SVT-AV1 4.2 says it won't insert keyframes at
+#   scene changes anyway, so it's likely a no-op here.
+SVT_PARAMS=film-grain=0:keyint=$(KEYINT):scd=1:tune=0:enable-variance-boost=1:enable-qm=1
 
 hevc-nvenc:
-	$(FFMPEG_CMD) \
+	$(FFMPEG_IN) -vf "$(SCALE),format=p010le" \
 		-c:v hevc_nvenc -preset p7 -tune hq -rc vbr -cq 14 -b:v 0 -maxrate 200M -bufsize 400M \
 		-profile:v main10 -pix_fmt p010le \
 		-spatial-aq 1 -aq-strength 6 -temporal-aq 1 \
 		-rc-lookahead 32 -bf 4 -b_ref_mode middle -multipass fullres \
-		-colorspace bt709 -color_primaries bt709 -color_trc bt709 -color_range tv \
+		$(COLOR_TAGS) \
 		-tag:v hvc1 -movflags +faststart \
 		$(OUT)
 
+# Delivery: CRF 17 (binding clip: VMAF 94.8 mean, 92.8 worst frame).
 x265:
-	$(FFMPEG_CMD) \
-		-c:v libx265 -crf 18 -preset medium -pix_fmt yuv420p10le \
-		-x265-params "aq-mode=3:no-sao=1" \
-		-colorspace bt709 -color_primaries bt709 -color_trc bt709 -color_range tv \
+	$(FFMPEG_IN) -vf "$(SCALE),format=yuv420p10le,$(TAG)" \
+		-c:v libx265 -profile:v main10 -preset medium -crf 17 \
+		-x265-params "$(X265_PARAMS)" \
+		$(COLOR_TAGS) \
 		-tag:v hvc1 -movflags +faststart \
 		$(OUT)
 
+# Master: CRF 12 (binding clip: 97.6 worst frame).
+x265-master:
+	$(FFMPEG_IN) -vf "$(SCALE),format=yuv420p10le,$(TAG)" \
+		-c:v libx265 -profile:v main10 -preset medium -crf 12 \
+		-x265-params "$(X265_PARAMS)" \
+		$(COLOR_TAGS) \
+		-tag:v hvc1 -movflags +faststart \
+		$(OUT)
+
+# Delivery: CRF 32 (binding clip: VMAF 95.0 mean, 93.4 worst frame).
 av1:
-	$(FFMPEG_CMD) \
-		-c:v libsvtav1 -crf 24 -preset 6 -pix_fmt yuv420p10le \
-		-svtav1-params "film-grain=0:enable-overlays=0" \
-		-colorspace bt709 -color_primaries bt709 -color_trc bt709 -color_range tv \
+	$(FFMPEG_IN) -vf "$(SCALE),format=yuv420p10le,$(TAG)" \
+		-c:v libsvtav1 -preset 6 -crf 32 \
+		-svtav1-params "$(SVT_PARAMS)" \
+		$(COLOR_TAGS) \
+		-movflags +faststart \
+		$(OUT)
+
+# Master: CRF 17 (binding clip: ~97.1 worst frame, interpolated from CRF 14/20).
+av1-master:
+	$(FFMPEG_IN) -vf "$(SCALE),format=yuv420p10le,$(TAG)" \
+		-c:v libsvtav1 -preset 6 -crf 17 \
+		-svtav1-params "$(SVT_PARAMS)" \
+		$(COLOR_TAGS) \
+		-movflags +faststart \
 		$(OUT)
diff --git a/tools/encode/.gitignore b/tools/encode/.gitignore
new file mode 100644
index 0000000..8031afc
--- /dev/null
+++ b/tools/encode/.gitignore
@@ -0,0 +1,3 @@
+clips/
+work/
+results/
diff --git a/tools/encode/README.md b/tools/encode/README.md
new file mode 100644
index 0000000..cfc15ba
--- /dev/null
+++ b/tools/encode/README.md
@@ -0,0 +1,126 @@
+# Encoder tuning
+
+The x265 and SVT-AV1 settings in the `Makefile` come from this harness. It
+encodes a few lossless 4K60 test clips with a list of configs, then scores
+every encode against its source with VMAF (4K model) and CAMBI (banding).
+
+```sh
+tools/encode/make_clips.sh                       # render clips/ once (~20 min on a GTX 1650)
+tools/encode/sweep.sh --tag x265 configs/x265-axes.txt
+tools/encode/sweep.sh --clips julia --keep --tag try my-configs.txt
+tools/encode/ladder.py results/x265-ladder.tsv   # CRF / Mb/s where each family meets the targets
+```
+
+Needs ffmpeg with libx265, libsvtav1 and libvmaf, the libvmaf models in
+`/usr/share/model` (`vmaf_4k_v0.6.1.json`, `vmaf_4k_v0.6.1neg.json`), and
+python3. `clips/`, `work/` and `results/` are git-ignored.
+
+## Clips
+
+`make_clips.sh` pipes `mandelbrot --headless --antialias` through the same
+RGBA → bt709 tv-range 10-bit conversion as the `Makefile` into lossless FFV1,
+so the clips are exactly what the encoders see and VMAF measures the encoder
+alone. Each is 4 s of 3840×2160 at 60 fps (`--size`/`--seconds` for quick tests).
+
+| clip | content | what it stresses |
+|---|---|---|
+| `filaments` | seahorse valley, 1e-8 → 3e-15 | dense detail under fast scaling motion |
+| `bands` | minibrot at 3.4e-21, 1e-18 → 1.1e-20 | smooth concentric gradients: banding, blocking |
+| `julia` | embedded Julia set at 2e-30, slow zoom | low-contrast fine texture on a bright background |
+
+`julia` turned out to be the hardest by far. At a CRF where the other two
+already score VMAF 99, both encoders smear its faint speckles, so it decides
+every tier's CRF.
+
+## Configs and results
+
+A config line is `name | ffmpeg output args`. `sweep.sh` encodes each clip,
+times it, and appends one row per encode to `results/<tag>.tsv`:
+
+| column | meaning |
+|---|---|
+| `fps` | encode speed, wall clock, all cores |
+| `mbps` | bitrate |
+| `vmaf`, `vmaf_p1`, `vmaf_min` | VMAF 4K mean, 1st percentile, min |
+| `vmaf_neg` | VMAF NEG: like VMAF, but doesn't reward sharpening |
+| `cambi`, `cambi_max` | banding, mean and worst frame (0 = none, above ~5 is visible) |
+| `psnr_y` | luma PSNR |
+
+VMAF uses every other frame (`n_subsample=2`). With 4 s clips that's 120
+frames, so `vmaf_p1` is the worst sampled frame. Both inputs are retimed by
+frame index before scoring. The MKV clips store 60 fps timestamps in whole
+milliseconds, and pairing by timestamp compared every third frame with its
+neighbour.
+
+`ladder.py` groups configs into families by stripping a trailing `-CRF`
+(`x265-rect-16` → `x265-rect`). It interpolates, per clip, the CRF and bitrate
+where each target is met. A tier has one CRF for all content, so the lowest of
+those CRFs binds it.
+
+The configs files are in the order they were run:
+
+- `speed.txt`: preset speed pass (which presets fit the time budget).
+- `crf-probe.txt`: coarse CRF ranges, to see where VMAF 95–97 land.
+- `x265-axes.txt`, `av1-axes.txt`: one option at a time from a baseline.
+- `*-ladder.txt`, `*-ladder2.txt`: the promising combinations at several CRFs,
+  to compare them at matched bitrate rather than at a fixed CRF.
+
+## Results (Ryzen 7 3700X, 8C/16T; ffmpeg 9.0, x265 4.3, SVT-AV1 4.2.0)
+
+Tier targets: **delivery** = VMAF mean ≈ 95 and worst frame ≥ 90 on every
+clip, smallest file. **Master** = worst frame ≥ 97 on every clip. `julia` binds
+every tier. "Interp" rows are interpolated between the two ladder rungs around
+that CRF (log bitrate, linear VMAF). Everything else was measured.
+
+| target | CRF | clip | Mb/s | fps | VMAF mean | p1 = min | CAMBI mean / max | |
+|---|---|---|---|---|---|---|---|---|
+| `x265` | 17 | bands | 279 | 2.4 | 99.93 | 98.81 | 1.53 / 6.00 | interp 16–20 |
+| | | filaments | 241 | 3.2 | 99.95 | 98.63 | 2.54 / 8.92 | interp 16–20 |
+| | | julia | 68 | 6.1 | 94.81 | 92.75 | 0 / 0 | interp 16–20 |
+| `x265-master` | 12 | bands | 466 | 1.8 | 100.00 | 100.00 | 1.58 / 6.19 | |
+| | | filaments | 342 | 2.8 | 100.00 | 99.99 | 2.65 / 9.49 | |
+| | | julia | 171 | 3.6 | 98.36 | 97.58 | 0 / 0 | |
+| `av1` | 32 | bands | 180 | 6.0 | 99.95 | 97.07 | 1.47 / 4.70 | |
+| | | filaments | 192 | 7.7 | 99.90 | 97.04 | 2.28 / 7.14 | |
+| | | julia | 50 | 7.4 | 95.03 | 93.39 | 0 / 0 | |
+| `av1-master` | 17 | bands | 451 | 6.9 | 100.00 | 99.49 | 1.23 / 4.87 | interp 14–20 |
+| | | filaments | 380 | 8.6 | 100.00 | 99.50 | 2.40 / 7.67 | interp 14–20 |
+| | | julia | 152 | 9.0 | 98.09 | 97.12 | 0 / 0 | interp 14–20 |
+
+SVT-AV1 wins both tiers: the delivery files are 20–35% smaller than
+x265's, and it encodes 1.2–2.5× faster. CAMBI max is the same at every CRF on
+`filaments` (6–9), so it comes from the content, not the encoder.
+
+What the sweeps showed (details as comments in the `Makefile`):
+
+- **SVT-AV1:** `tune=0` + `enable-variance-boost=1` + `enable-qm=1` is the
+  combination that fixes faint texture. With the defaults, `julia` scores a
+  worst frame of 85 at CRF 26. The temporal filter (`enable-tf`) was the
+  suspect for smeared filaments, but turning it off or weakening it cost
+  35–50% more bits for lower VMAF and more banding. `qm-min=0` caps quality.
+  `sharpness`, `ac-bias` and `enable-overlays` did nothing measurable.
+- **x265:** `rect`, `merange=92` and `rdoq-level=2:psy-rdoq=1` help. SAO hurts.
+  `aq-mode=4`, `deblock=-1`, `psy-rd=1`, `me=star`, `rc-lookahead=60` and
+  `bframes=8` didn't help at matched bitrate or cost too much speed.
+- The worst SVT frames without variance boost sit in the clip's last
+  mini-GOP, so part of that p1 is an artefact of a 4 s clip.
+
+**Speed budget.** It was 3–5 fps on an i7-1165G7 (4C/8T). Pinning this machine
+to 4C/8T (`taskset -c 0-3,8-11`) as a proxy gives 1.5× (SVT) to 1.8× (x265)
+for the full 16 threads, so here the budget is about 5–9 fps. SVT preset 6
+fits at both tiers. x265 `medium` with these options doesn't: at the low CRFs
+`julia` forces, it runs at 2–6 fps. This SVT-AV1 package also reports
+`(debug)`: it's built without `NDEBUG`, but it's optimised and it's what
+ffmpeg links.
+
+**Not yet measured:** x265 `-preset fast` with these options (the speed fix
+for x265) and `aq-strength=1.2` (`configs/x265-ladder2.txt`). Also a
+confirming encode at `av1-master`'s interpolated CRF 17.
+
+## Tips
+
+- Keep the machine idle while sweeping: `fps` is wall clock time.
+- A config that changes bitrate at a fixed CRF can't be judged from one row.
+  Put it on a ladder and compare with `ladder.py`.
+- `--keep` keeps the encodes in `work/`, e.g. to extract frames to compare by eye:
+  `ffmpeg -i work/julia--x.mp4 -vf "select=eq(n\,120),crop=480:270:1680:945" -frames:v 1 x.png`.
diff --git a/tools/encode/configs/av1-axes.txt b/tools/encode/configs/av1-axes.txt
new file mode 100644
index 0000000..09ebcd4
--- /dev/null
+++ b/tools/encode/configs/av1-axes.txt
@@ -0,0 +1,16 @@
+# SVT-AV1 4.2 per-axis sweep: each line changes one thing from av1-base.
+# Base = pass-1 settings (preset 6, no film grain) plus a 10 s GOP and scene-cut detection.
+av1-base       | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 30 -svtav1-params film-grain=0:keyint=600:scd=1
+# ffmpeg's libsvtav1 defaults to tune=1 (PSNR); 0 is the visual-quality tune
+av1-tune0      | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 30 -svtav1-params film-grain=0:keyint=600:scd=1:tune=0
+# Alt-ref temporal filter: prime suspect for smeared filaments during zooms
+av1-tf0        | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 30 -svtav1-params film-grain=0:keyint=600:scd=1:enable-tf=0
+av1-tfs1       | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 30 -svtav1-params film-grain=0:keyint=600:scd=1:tf-strength=1
+# Variance boost: more bits to flat, low-variance blocks (gradient banding)
+av1-vb         | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 30 -svtav1-params film-grain=0:keyint=600:scd=1:enable-variance-boost=1
+av1-vb3        | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 30 -svtav1-params film-grain=0:keyint=600:scd=1:enable-variance-boost=1:variance-boost-strength=3
+# Quantisation matrices, deblocking sharpness, AC bias (texture), overlays
+av1-qm         | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 30 -svtav1-params film-grain=0:keyint=600:scd=1:enable-qm=1:qm-min=0
+av1-sharp1     | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 30 -svtav1-params film-grain=0:keyint=600:scd=1:sharpness=1
+av1-acb1       | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 30 -svtav1-params film-grain=0:keyint=600:scd=1:ac-bias=1.0
+av1-ov1        | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 30 -svtav1-params film-grain=0:keyint=600:scd=1:enable-overlays=1
diff --git a/tools/encode/configs/av1-ladder.txt b/tools/encode/configs/av1-ladder.txt
new file mode 100644
index 0000000..0d956bf
--- /dev/null
+++ b/tools/encode/configs/av1-ladder.txt
@@ -0,0 +1,19 @@
+# SVT-AV1 candidate ladders: compare combinations at matched bitrate (results/av1-ladder.tsv)
+av1-c0-14              | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 14 -svtav1-params film-grain=0:keyint=600:scd=1
+av1-c0-20              | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 20 -svtav1-params film-grain=0:keyint=600:scd=1
+av1-c0-26              | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 26 -svtav1-params film-grain=0:keyint=600:scd=1
+av1-qm-14              | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 14 -svtav1-params film-grain=0:keyint=600:scd=1:enable-qm=1:qm-min=0
+av1-qm-20              | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 20 -svtav1-params film-grain=0:keyint=600:scd=1:enable-qm=1:qm-min=0
+av1-qm-26              | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 26 -svtav1-params film-grain=0:keyint=600:scd=1:enable-qm=1:qm-min=0
+av1-tune0-14           | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 14 -svtav1-params film-grain=0:keyint=600:scd=1:tune=0
+av1-tune0-20           | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 20 -svtav1-params film-grain=0:keyint=600:scd=1:tune=0
+av1-tune0-26           | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 26 -svtav1-params film-grain=0:keyint=600:scd=1:tune=0
+av1-vb-14              | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 14 -svtav1-params film-grain=0:keyint=600:scd=1:enable-variance-boost=1
+av1-vb-20              | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 20 -svtav1-params film-grain=0:keyint=600:scd=1:enable-variance-boost=1
+av1-vb-26              | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 26 -svtav1-params film-grain=0:keyint=600:scd=1:enable-variance-boost=1
+av1-qm-vb-14           | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 14 -svtav1-params film-grain=0:keyint=600:scd=1:enable-qm=1:qm-min=0:enable-variance-boost=1
+av1-qm-vb-20           | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 20 -svtav1-params film-grain=0:keyint=600:scd=1:enable-qm=1:qm-min=0:enable-variance-boost=1
+av1-qm-vb-26           | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 26 -svtav1-params film-grain=0:keyint=600:scd=1:enable-qm=1:qm-min=0:enable-variance-boost=1
+av1-qm-vb-tune0-14     | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 14 -svtav1-params film-grain=0:keyint=600:scd=1:enable-qm=1:qm-min=0:enable-variance-boost=1:tune=0
+av1-qm-vb-tune0-20     | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 20 -svtav1-params film-grain=0:keyint=600:scd=1:enable-qm=1:qm-min=0:enable-variance-boost=1:tune=0
+av1-qm-vb-tune0-26     | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 26 -svtav1-params film-grain=0:keyint=600:scd=1:enable-qm=1:qm-min=0:enable-variance-boost=1:tune=0
diff --git a/tools/encode/configs/av1-ladder2.txt b/tools/encode/configs/av1-ladder2.txt
new file mode 100644
index 0000000..920ea0f
--- /dev/null
+++ b/tools/encode/configs/av1-ladder2.txt
@@ -0,0 +1,12 @@
+# SVT-AV1 round 2: tune0+VB without QM, default qm-min, delivery-range CRFs (results/av1-ladder2.tsv)
+av1-vb-tune0-14            | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 14 -svtav1-params film-grain=0:keyint=600:scd=1:tune=0:enable-variance-boost=1
+av1-vb-tune0-20            | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 20 -svtav1-params film-grain=0:keyint=600:scd=1:tune=0:enable-variance-boost=1
+av1-vb-tune0-26            | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 26 -svtav1-params film-grain=0:keyint=600:scd=1:tune=0:enable-variance-boost=1
+av1-vb-tune0-32            | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 32 -svtav1-params film-grain=0:keyint=600:scd=1:tune=0:enable-variance-boost=1
+av1-qm8-vb-tune0-14        | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 14 -svtav1-params film-grain=0:keyint=600:scd=1:tune=0:enable-qm=1:enable-variance-boost=1
+av1-qm8-vb-tune0-20        | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 20 -svtav1-params film-grain=0:keyint=600:scd=1:tune=0:enable-qm=1:enable-variance-boost=1
+av1-qm8-vb-tune0-26        | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 26 -svtav1-params film-grain=0:keyint=600:scd=1:tune=0:enable-qm=1:enable-variance-boost=1
+av1-qm8-vb-tune0-32        | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 32 -svtav1-params film-grain=0:keyint=600:scd=1:tune=0:enable-qm=1:enable-variance-boost=1
+av1-qm-vb-tune0-32         | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 32 -svtav1-params film-grain=0:keyint=600:scd=1:tune=0:enable-qm=1:qm-min=0:enable-variance-boost=1
+av1-qm-vb-tune0-38         | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 38 -svtav1-params film-grain=0:keyint=600:scd=1:tune=0:enable-qm=1:qm-min=0:enable-variance-boost=1
+av1-tune0-10               | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 10 -svtav1-params film-grain=0:keyint=600:scd=1:tune=0
diff --git a/tools/encode/configs/crf-probe.txt b/tools/encode/configs/crf-probe.txt
new file mode 100644
index 0000000..8198df5
--- /dev/null
+++ b/tools/encode/configs/crf-probe.txt
@@ -0,0 +1,9 @@
+# Coarse CRF probe: where do VMAF 95-97 land on each clip? (pass-1 baselines)
+x265-crf22 | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 22 -x265-params log-level=error:aq-mode=3:no-sao=1
+x265-crf26 | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 26 -x265-params log-level=error:aq-mode=3:no-sao=1
+x265-crf30 | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 30 -x265-params log-level=error:aq-mode=3:no-sao=1
+x265-crf34 | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 34 -x265-params log-level=error:aq-mode=3:no-sao=1
+av1-crf32  | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 32 -svtav1-params film-grain=0
+av1-crf38  | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 38 -svtav1-params film-grain=0
+av1-crf44  | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 44 -svtav1-params film-grain=0
+av1-crf50  | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 50 -svtav1-params film-grain=0
diff --git a/tools/encode/configs/speed.txt b/tools/encode/configs/speed.txt
new file mode 100644
index 0000000..f43a07c
--- /dev/null
+++ b/tools/encode/configs/speed.txt
@@ -0,0 +1,8 @@
+# Pass 1: which presets fit the 3-5 fps budget at 4K on this machine.
+x265-fast      | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset fast   -crf 18 -x265-params log-level=error:aq-mode=3:no-sao=1
+x265-medium    | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 18 -x265-params log-level=error:aq-mode=3:no-sao=1
+x265-slow      | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset slow   -crf 18 -x265-params log-level=error:aq-mode=3:no-sao=1
+av1-p5         | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 5 -crf 26 -svtav1-params film-grain=0
+av1-p6         | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 6 -crf 26 -svtav1-params film-grain=0
+av1-p7         | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 7 -crf 26 -svtav1-params film-grain=0
+av1-p8         | -pix_fmt yuv420p10le -c:v libsvtav1 -preset 8 -crf 26 -svtav1-params film-grain=0
diff --git a/tools/encode/configs/x265-axes.txt b/tools/encode/configs/x265-axes.txt
new file mode 100644
index 0000000..e2b9429
--- /dev/null
+++ b/tools/encode/configs/x265-axes.txt
@@ -0,0 +1,20 @@
+# x265 per-axis sweep: each line changes one thing from x265-base.
+# Base = pass-1 settings (preset medium, aq-mode 3, no SAO) plus a 10 s GOP.
+x265-base      | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1
+# Adaptive quantisation
+x265-aq4       | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=4:no-sao=1
+x265-aqs08     | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:aq-strength=0.8:no-sao=1
+x265-aqs12     | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:aq-strength=1.2:no-sao=1
+# In-loop filters
+x265-sao       | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3
+x265-selsao2   | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:selective-sao=2
+x265-deblk-1   | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:deblock=-1,-1
+# Psychovisual: medium has rdoq-level 0, so psy-rdoq needs rdoq-level 2 to do anything
+x265-psyrdoq   | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:rdoq-level=2:psy-rdoq=1.0
+x265-psyrd1    | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:psy-rd=1.0
+# Motion: zooms are scaling, not translation
+x265-star      | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:me=star
+x265-mer92     | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:merange=92
+x265-bf8       | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:bframes=8
+x265-la60      | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:rc-lookahead=60
+x265-rect      | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:rect=1
diff --git a/tools/encode/configs/x265-ladder.txt b/tools/encode/configs/x265-ladder.txt
new file mode 100644
index 0000000..7769455
--- /dev/null
+++ b/tools/encode/configs/x265-ladder.txt
@@ -0,0 +1,13 @@
+# x265 candidate ladders: compare combinations at matched bitrate (results/x265-ladder.tsv)
+x265-c0-12             | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 12 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:merange=92
+x265-c0-16             | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 16 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:merange=92
+x265-c0-20             | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:merange=92
+x265-rect-12           | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 12 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:merange=92:rect=1
+x265-rect-16           | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 16 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:merange=92:rect=1
+x265-rect-20           | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:merange=92:rect=1
+x265-rect-psyrdoq-12   | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 12 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:merange=92:rect=1:rdoq-level=2:psy-rdoq=1.0
+x265-rect-psyrdoq-16   | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 16 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:merange=92:rect=1:rdoq-level=2:psy-rdoq=1.0
+x265-rect-psyrdoq-20   | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:merange=92:rect=1:rdoq-level=2:psy-rdoq=1.0
+x265-rect-aq4-12       | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 12 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=4:no-sao=1:merange=92:rect=1
+x265-rect-aq4-16       | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 16 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=4:no-sao=1:merange=92:rect=1
+x265-rect-aq4-20       | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=4:no-sao=1:merange=92:rect=1
diff --git a/tools/encode/configs/x265-ladder2.txt b/tools/encode/configs/x265-ladder2.txt
new file mode 100644
index 0000000..0e39413
--- /dev/null
+++ b/tools/encode/configs/x265-ladder2.txt
@@ -0,0 +1,7 @@
+# x265 round 2: preset fast for speed, aq-strength 1.2 for julia (results/x265-ladder2.tsv)
+x265-fast-rp-12            | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset fast -crf 12 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:merange=92:rect=1:rdoq-level=2:psy-rdoq=1.0
+x265-fast-rp-16            | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset fast -crf 16 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:merange=92:rect=1:rdoq-level=2:psy-rdoq=1.0
+x265-fast-rp-20            | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset fast -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:merange=92:rect=1:rdoq-level=2:psy-rdoq=1.0
+x265-rp-aqs12-12           | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 12 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:merange=92:rect=1:rdoq-level=2:psy-rdoq=1.0:aq-strength=1.2
+x265-rp-aqs12-16           | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 16 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:merange=92:rect=1:rdoq-level=2:psy-rdoq=1.0:aq-strength=1.2
+x265-rp-aqs12-20           | -pix_fmt yuv420p10le -c:v libx265 -profile:v main10 -preset medium -crf 20 -x265-params log-level=error:keyint=600:min-keyint=60:aq-mode=3:no-sao=1:merange=92:rect=1:rdoq-level=2:psy-rdoq=1.0:aq-strength=1.2
diff --git a/tools/encode/ladder.py b/tools/encode/ladder.py
new file mode 100755
index 0000000..fe33983
--- /dev/null
+++ b/tools/encode/ladder.py
@@ -0,0 +1,62 @@
+#!/usr/bin/env python3
+"""Where does each config family meet a VMAF target? Reads sweep.sh TSVs.
+
+    tools/encode/ladder.py results/x265-ladder.tsv [--target vmaf:95 --target p1:90 ...]
+
+A family is a config name minus its trailing -CRF (x265-rect-16 -> x265-rect;
+x265-crf16 -> x265).
+For each family and clip, log(Mb/s) and CRF are interpolated linearly in the
+chosen metric between the two ladder rungs that bracket the target. A tier
+uses one CRF for everything, so the clip needing the lowest CRF binds it; that
+CRF is printed last as "all". A dash means the ladder doesn't reach the target.
+"""
+import argparse
+import csv
+import math
+import re
+from collections import defaultdict
+
+ap = argparse.ArgumentParser()
+ap.add_argument("tsv", nargs="+")
+ap.add_argument("--target", action="append",
+                help="metric:value, metric one of vmaf, p1, min, neg (default vmaf:95, p1:90, p1:97)")
+args = ap.parse_args()
+targets = [(m, float(v)) for m, v in (t.split(":") for t in (args.target or ["vmaf:95", "p1:90", "p1:97"]))]
+col = {"vmaf": "vmaf", "p1": "vmaf_p1", "min": "vmaf_min", "neg": "vmaf_neg"}
+
+fam = defaultdict(lambda: defaultdict(list))  # family -> clip -> [(crf, row)]
+for path in args.tsv:
+    for r in csv.DictReader(open(path), delimiter="\t"):
+        m = re.fullmatch(r"(.*)-(?:crf)?(\d+)", r["config"])
+        if m:
+            fam[m[1]][r["clip"]].append((int(m[2]), r))
+
+
+def solve(pts, key, target):
+    """(crf, mbps, fps) where metric `key` crosses `target`, or None."""
+    pts = sorted(pts, key=lambda p: p[0])  # quality falls as CRF rises
+    for (c0, a), (c1, b) in zip(pts, pts[1:]):
+        q0, q1 = float(a[key]), float(b[key])
+        if q0 >= target >= q1 and q0 != q1:
+            t = (q0 - target) / (q0 - q1)
+            lr = math.log(float(a["mbps"])) * (1 - t) + math.log(float(b["mbps"])) * t
+            fps = float(a["fps"]) * (1 - t) + float(b["fps"]) * t
+            return c0 + t * (c1 - c0), math.exp(lr), fps
+    return None
+
+
+for metric, target in targets:
+    print(f"\n## {metric} >= {target:g}   (CRF @ Mb/s, fps)")
+    clips = sorted({c for f in fam.values() for c in f})
+    print(f"{'family':24}" + "".join(f"{c:>22}" for c in clips) + f"{'all (binding clip)':>24}")
+    for f, per in fam.items():
+        cells, worst = [], None
+        for c in clips:
+            s = solve(per.get(c, []), col[metric], target)
+            cells.append(f"{s[0]:5.1f} @ {s[1]:6.1f}, {s[2]:4.1f}" if s else "-")
+            if s is None:
+                worst = "missing"
+            elif worst != "missing" and (worst is None or s[0] < worst[0]):
+                worst = (s[0], c)
+        w = "-" if worst in (None, "missing") else f"CRF {worst[0]:4.1f} ({worst[1]})"
+        print(f"{f:24}" + "".join(f"{x:>22}" for x in cells) + f"{w:>24}")
diff --git a/tools/encode/make_clips.sh b/tools/encode/make_clips.sh
new file mode 100755
index 0000000..8e6f625
--- /dev/null
+++ b/tools/encode/make_clips.sh
@@ -0,0 +1,70 @@
+#!/usr/bin/env bash
+# Render the lossless 4K60 test clips that sweep.sh encodes.
+#
+# Each clip goes through the same RGBA -> bt709 tv-range 10-bit conversion as
+# the Makefile, then into lossless FFV1. The clips are therefore exactly what the
+# encoders see, so VMAF against them measures the encoder alone.
+#
+#   tools/encode/make_clips.sh [--size WxH] [--seconds S] [--force] [clip...]
+set -euo pipefail
+
+here=$(cd "$(dirname "$0")" && pwd)
+root=$(cd "$here/../.." && pwd)
+out="$here/clips"
+size=3840x2160
+seconds=4
+fps=60
+force=0
+only=()
+
+while [[ $# -gt 0 ]]; do
+    case $1 in
+        --size) size=$2; shift 2 ;;
+        --seconds) seconds=$2; shift 2 ;;
+        --force) force=1; shift ;;
+        -h|--help) sed -n '2,9p' "$0"; exit 0 ;;
+        *) only+=("$1"); shift ;;
+    esac
+done
+
+# Seahorse valley, minibrot at 3.7e-41 (tools/deep-zoom/LOCATIONS.md).
+SH_RE=-0.77568376800905379745347652613832924487504096622022
+SH_IM=0.13646736829469012473375311880735014411233827361594
+# Seahorse valley, minibrot at 3.4e-21 (period 429, `find_deep.py seahorse 10`).
+# Same look as the 1e-40 one for this purpose, but ~10x faster to render.
+MB_RE=-0.775683767855941232535147681616
+MB_IM=0.136467368300490586441979944945
+
+# name | mandelbrot flags. Zoom speeds bracket a typical 60 s dive (~0.7 decade/s).
+clips=(
+    # Worst case: dense filaments, 1.5 decades/s of scaling motion.
+    "filaments|--view=$SH_RE,$SH_IM,1e-8 --to-view=$SH_RE,$SH_IM,3e-15 --linear"
+    # Smooth concentric bands closing in on the minibrot: banding/blocking risk.
+    "bands|--view=$MB_RE,$MB_IM,1e-18 --to-view=$MB_RE,$MB_IM,1.1e-20 --linear"
+    # Embedded Julia set, slow drift: fine static texture, psy/detail retention.
+    "julia|--view=$SH_RE,$SH_IM,2e-30 --to-view=$SH_RE,$SH_IM,1e-30 --linear"
+)
+
+[[ -x $root/target/release/mandelbrot ]] || cargo build --release --manifest-path "$root/Cargo.toml"
+mkdir -p "$out"
+w=${size%x*}
+h=${size#*x}
+
+for entry in "${clips[@]}"; do
+    name=${entry%%|*}
+    flags=${entry#*|}
+    if [[ ${#only[@]} -gt 0 && ! " ${only[*]} " =~ " $name " ]]; then continue; fi
+    dst="$out/$name.mkv"
+    if [[ -f $dst && $force = 0 ]]; then echo "skip $name (exists, --force to redo)"; continue; fi
+    echo "render $name ($size, ${seconds}s @ ${fps}fps)"
+    # shellcheck disable=SC2086
+    "$root/target/release/mandelbrot" --headless --antialias $flags \
+        --width "$w" --height "$h" --fps "$fps" --duration "$seconds" --export-path - |
+        ffmpeg -hide_banner -loglevel error -y \
+            -f rawvideo -pix_fmt rgba -s "$size" -framerate "$fps" -i - \
+            -vf "scale=out_color_matrix=bt709:out_range=tv:flags=accurate_rnd+full_chroma_int+bitexact,format=yuv420p10le" \
+            -c:v ffv1 -level 3 -slices 16 -g 1 \
+            -colorspace bt709 -color_primaries bt709 -color_trc bt709 -color_range tv \
+            "$dst.tmp.mkv"
+    mv "$dst.tmp.mkv" "$dst"
+done
diff --git a/tools/encode/sweep.sh b/tools/encode/sweep.sh
new file mode 100755
index 0000000..7260e42
--- /dev/null
+++ b/tools/encode/sweep.sh
@@ -0,0 +1,89 @@
+#!/usr/bin/env bash
+# Encode every test clip with every config, then score each encode.
+#
+#   tools/encode/sweep.sh [--clips a,b] [--keep] [--tag NAME] CONFIG_FILE...
+#
+# A config line is `name | ffmpeg output args` (blank lines and # comments are
+# skipped). The args go between `-i clip.mkv` and the output file, e.g.
+#   x265-crf18 | -c:v libx265 -preset medium -crf 18 -x265-params aq-mode=3
+# Each row of results/<tag>.tsv has encode fps, bitrate, VMAF 4K (mean, 1st
+# percentile, min), VMAF-NEG mean, CAMBI banding (mean, max) and PSNR-Y.
+set -euo pipefail
+
+here=$(cd "$(dirname "$0")" && pwd)
+clipdir="$here/clips"
+model=/usr/share/model
+export SVT_LOG=1  # errors only
+clips=""
+keep=0
+tag=$(date +%Y%m%d-%H%M%S)
+configs=()
+
+while [[ $# -gt 0 ]]; do
+    case $1 in
+        --clips) clips=$2; shift 2 ;;
+        --keep) keep=1; shift ;;
+        --tag) tag=$2; shift 2 ;;
+        -h|--help) sed -n '2,11p' "$0"; exit 0 ;;
+        *) configs+=("$1"); shift ;;
+    esac
+done
+[[ ${#configs[@]} -gt 0 ]] || { echo "usage: $0 [--clips a,b] [--keep] [--tag NAME] CONFIG_FILE..." >&2; exit 1; }
+
+if [[ -z $clips ]]; then
+    clips=$(cd "$clipdir" && ls ./*.mkv | sed 's|^\./||; s|\.mkv$||' | paste -sd,)
+fi
+[[ -n $clips ]] || { echo "no clips in $clipdir: run make_clips.sh first" >&2; exit 1; }
+
+mkdir -p "$here/results" "$here/work"
+tsv="$here/results/$tag.tsv"
+[[ -f $tsv ]] || printf 'clip\tconfig\tfps\tmbps\tvmaf\tvmaf_p1\tvmaf_min\tvmaf_neg\tcambi\tcambi_max\tpsnr_y\n' > "$tsv"
+
+IFS=, read -ra clip_list <<< "$clips"
+for cfg in "${configs[@]}"; do
+    while IFS= read -r line || [[ -n $line ]]; do
+        [[ $line =~ ^[[:space:]]*(#|$) ]] && continue
+        name=$(sed 's/[[:space:]]*|.*//' <<< "$line")
+        args=$(sed 's/^[^|]*|[[:space:]]*//' <<< "$line")
+        for clip in "${clip_list[@]}"; do
+            ref="$clipdir/$clip.mkv"
+            enc="$here/work/$clip--$name.mp4"
+            log="$here/work/$clip--$name.json"
+            frames=$(ffprobe -v error -count_packets -select_streams v:0 \
+                -show_entries stream=nb_read_packets -of csv=p=0 "$ref")
+            printf '%-10s %-40s ' "$clip" "$name"
+
+            t0=$(date +%s.%N)
+            # shellcheck disable=SC2086
+            ffmpeg -hide_banner -loglevel error -y -i "$ref" $args -an "$enc" < /dev/null
+            t1=$(date +%s.%N)
+
+            # 4K model for both VMAF variants; CAMBI flags banding, which VMAF
+            # barely sees and which is the main risk on smooth fractal gradients.
+            # Both streams are retimed by frame index: MKV stores 60 fps in whole
+            # ms, and pairing by PTS matched every third frame with its neighbour.
+            ffmpeg -hide_banner -loglevel error -i "$enc" -i "$ref" -lavfi \
+                "[0:v]settb=1/60,setpts=N[d];[1:v]settb=1/60,setpts=N[r];[d][r]libvmaf=log_fmt=json:log_path=$log:n_threads=$(nproc):n_subsample=2:model='path=$model/vmaf_4k_v0.6.1.json\\:name=vmaf|path=$model/vmaf_4k_v0.6.1neg.json\\:name=neg':feature='name=cambi|name=psnr'" \
+                -f null - < /dev/null
+
+            row=$(python3 - "$log" "$enc" "$frames" "$t0" "$t1" <<'PY'
+import json, os, sys
+log, enc, frames, t0, t1 = sys.argv[1], sys.argv[2], int(sys.argv[3]), float(sys.argv[4]), float(sys.argv[5])
+fr = json.load(open(log))["frames"]
+col = lambda k: sorted(f["metrics"][k] for f in fr)
+v = col("vmaf")
+p1 = v[max(0, int(0.01 * len(v)) - 1)] if len(v) >= 100 else v[0]
+mean = lambda xs: sum(xs) / len(xs)
+cambi = col("cambi")
+fps = frames / (t1 - t0)
+mbps = os.path.getsize(enc) * 8 / (frames / 60) / 1e6
+print(f"{fps:.2f}\t{mbps:.1f}\t{mean(v):.2f}\t{p1:.2f}\t{v[0]:.2f}\t{mean(col('neg')):.2f}\t{mean(cambi):.2f}\t{cambi[-1]:.2f}\t{mean(col('psnr_y')):.2f}")
+PY
+)
+            printf '%s\t%s\t%s\n' "$clip" "$name" "$row" >> "$tsv"
+            awk -F'\t' '{printf "%6s fps %7s Mb/s  vmaf %s p1 %s min %s neg %s  cambi %s/%s  psnr %s\n",$1,$2,$3,$4,$5,$6,$7,$8,$9}' <<< "$row"
+            [[ $keep = 1 ]] || rm -f "$enc"
+        done
+    done < "$cfg"
+done
+echo "results: $tsv"