The alignment machinery never modified a scan: it produced an
AlignmentResult and every consumer resampled on the fly. That is right
for a viewer but means the aligned stack cannot leave the process, so no
other tool can read it and reopening the scan redoes the registration.
sras_align_export.write_aligned_sras bakes an alignment into a new v6
file: each angle is gathered onto the shared canvas by nearest neighbour,
so every output angle shares one grid and the file opens already aligned.
Registering the export against itself returns identity, which is the test
that pins the whole index chain.
Three details that are easy to get wrong and are now covered:
* Rounding must be floor(x + 0.5), not np.rint. scipy's order=0 rounds
halves away from zero, and the canvas is snapped to the reference's
pixel grid, so exact halves are common rather than hypothetical.
* Out-of-bounds must be tested on the fractional coordinate against
[0, n-1], not on the rounded index, or a one-pixel rim gets real data
everywhere the Aligned View shows padding.
* ...but with a tolerance, because the mm-space affine chain lands an
exactly-integer transform a few times 1e-13 off. A bare >= 0 drops
the *reference* angle's entire first row and last column.
Padding is the per-channel ADC code nearest 0 mV, not zero: zero ADC
decodes to ~+100 mV on real calibration and would masquerade as sample.
Source rows are served from sliding in-RAM bands. A rotated angle maps
one output row to a diagonal across the source, so indexing a memmap in
output order refaults nearly the whole angle per row — terabytes of
paging for a gigabyte of data.
Also in compute: crop_alignment_result (a crop is pure index translation,
so it folds into the affine's offset rather than becoming a second
transform), overlap_stats, largest_rect_at_least for a crop that stays
inside the overlap region, and seed/sign/refine knobs on
register_angle_to_reference whose defaults leave existing behaviour and
tests byte-identical.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The 2790-line module becomes sras_viewer/: common.py (constants +
layout helpers), canvases.py (RoiQuad, ImageCanvas, WaveformCanvas,
ManualAlignOverlayCanvas), dialogs.py (FftOptionsDialog,
ManualAlignmentDialog), main_window.py (SrasViewerWindow + main), with
__init__ re-exporting the public names and __main__ keeping
`python -m sras_viewer` working. pyproject gains a `sras-viewer`
console script.
Code moved verbatim; only import headers are new (pyflakes-clean).
tests/test_gui.py patch targets follow the classes to their new
modules.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
- SrasFile: _parse_v6 now retains per-angle x_delta and the verbatim
preamble/background byte spans, and gains public data_offset,
y_pos_per_angle, and iter_angle_blocks() (which now owns the ragged
block-offset walk used three separate places before).
- sras_edit_scans: the 70-line re-parse of the v6 header sections
(_read_v6_sections/_reread_span/_v6_angle_offsets) collapses into a
_write_v6 that consumes SrasFile directly — verified byte-identical
round-trip on v6 int8/int16 and legacy files. Eight print-and-exit
pairs become _die().
- tools/make_test_sras imports the struct layouts from sras_format and
the rotation matrix from sras_compute instead of re-declaring them
(byte assembly stays independent of the reader).
- sras_compute: block_mean_2d, pixel_pitch_mm, nominal_delta_deg made
public (they were GUI-facing); registration_workers() and
default_max_workers() wrap the remaining private reach-throughs from
sras_workers.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
- FFT backend and pad factor persist across sessions via QSettings
(IniFormat; tests redirect the settings path for hermeticity).
- The default backend was labelled "NumPy FFT" but always dispatched to
scipy.fft — rename the canonical value to "scipy" ("numpy" stays as a
legacy alias) and fix the dialog label.
- cache_file: DC caching fans out over angles via _parallel_map with
per-angle budgets (the DcPrecomputeWorker pattern); FFT caching stays
serial per angle because compute_rf_image now parallelises internally
over blocks. Documented that the v7 FFT cache is natural-resolution
(pad 1) by design.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
At pad 40 the old path materialised a ~9 GB padded spectrum per row,
which collapsed the chunk planner to one worker and one rfft call with
workers=1 — synthesis ran single-threaded, ~1 hour per angle on real
files.
The padded spectrum is never materialised now. Each block of 512
waveforms gets a coarse rfft at next_fast_len(2*spf); every coarse bin
within 0.7 of its row's max (plus the DC-adjacent window, which coarse
DC suppression would otherwise blind) is refined onto the exact n_fft
grid by a small complex gemm. The selected bin is bit-identical to the
full padded argmax — enforced by test_zoom_identity, a 25-seed fuzz
test over adversarial spectra, and a clean golden-hash diff against the
pre-rewrite baseline across pads {1,2,4,8,40}, masked/unmasked, bg
on/off, int8/int16, and both backends.
Blocks fan out over a persistent thread pool; pyFFTW runs through
per-thread FFTW_MEASURE builder plans with wisdom persisted to
~/.cache/sras-viewer, and threadpoolctl clamps BLAS under the pool.
compute_rf_image(exact=True) (or SRAS_FFT_EXACT=1) keeps the reference
padded path for audits.
tools/bench_fft.py measures: pad 40, 16 cores, 8192x2500 synthetic —
exact serial 717 wf/s -> zoom pool 25100 wf/s (35x, pyFFTW backend;
19x scipy), every variant verified equal to the reference.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
- pyproject.toml replaces sras_viewer_requirements.txt (same pins) and
adds a dev extra with pytest.
- tools/test_refactor.py, test_alignment.py, test_gui.py become
tests/test_compute.py, tests/test_alignment.py, tests/test_gui.py with
assertions preserved verbatim. test_gui.py stays one ordered
integration sequence over a shared module-scoped window.
- check_equivalence.py: drop the dead pre-refactor monolith shim (and the
_compute_angle_alignment alias it consumed), extend the pad sweep to
(1, 2, 4, 8, 40), add legacy-v4 and big-endian int16 legs (new bps=2
option in make_test_sras) so the padded FFT path and the >i2 memmap
path are in the baseline before the FFT rewrite.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Thomas Ales