ISOVELA 1.0.0
Scientific image study desk - independent Avenrift companion

Run portable/Isovela.exe on 64-bit Windows 10 or Windows 11. No installation,
administrator access, account, downloaded runtime or adjacent DLL is required.
The application is a native C++ executable with a statically linked runtime.
All original Avenrift functionality remains available in Avenrift.

PURPOSE
Isovela focuses on image observations, rather than feeds and story boards.
Study the embedded NASA Cosmic Cliffs plate offline or open local PNG, JPEG,
BMP and TIFF images. Pan, zoom, inspect original pixels, attach coordinate-based
notes, export a crop as PNG and export observations as JSON and CSV.
The original scientific image is embedded unchanged: 130,764,157 bytes,
14,575 x 8,441 pixels. Its useful full-resolution data accounts for almost all
of the executable's size. There is no padding, executable payload or runtime
extraction. The application does not extract the plate on launch.

WORKFLOW
1. NASA plate opens the built-in image. Drop one local image on the window,
   or paste an absolute path and select Open image. Network paths are rejected.
2. Drag to pan, use the wheel to zoom, F to fit or 1 for original pixels.
3. Add marker (M), then click an image detail. Type a field note in the right
   panel; it autosaves after a brief pause. Click a marker to return to it.
4. Remove marker removes the selected observation. Undo removal restores the
   last removed marker while retaining other subsequent edits.
5. Select crop (C) and drag a rectangle. Export crop PNG writes source pixels,
   without marker overlays, and JSON with source SHA-256 and crop coordinates.
6. Export notes writes a complete JSON sheet and spreadsheet-safe CSV.
   Export folder opens the output directory in Windows Explorer.
7. Close or minimize keeps the app in the tray and releases the large decoded
   image. Reopen through the tray. Right-click the tray and select Quit Isovela
   to stop the process. No startup registration is created.

LIMITS AND DATA
Input: at most 200 MiB, 150,000,000 pixels, and 20,000 pixels per side.
TIFF and other multiple-frame images use the first frame. Pixel orientation
is as stored; EXIF rotation and color-managed proofing are not implemented.
Windows' built-in codecs decode images in memory. Source files are read-only.
Crop export: at most 25,000,000 original pixels; no copied image metadata.
Allow about 2 GB of free memory while opening large images.
At most 200 markers per image, with notes limited to 2,400 UTF-16 code units.
The image-byte SHA-256 identifies each sheet. A changed image receives a
different sheet; renaming an unchanged file preserves its observations.

Local, unencrypted data:
  %LOCALAPPDATA%\Isovela\observations\<image-sha256>.json
  %LOCALAPPDATA%\Isovela\exports\
Successful replacements preserve the previous sheet as .bak. Damaged files
are preserved; the app uses a separate .recovery.json sheet when needed.
If a write fails, unsaved changes remain in memory and closing or switching
images is blocked until saving succeeds. An unreadable image leaves the
previous image available. Failed exports may leave a completed partial pair;
retrying writes a new unique export, never overwriting the source.
There is no telemetry, account, server, auto-updater or diagnostic log.

LANGUAGE AND SOUND
English, Spanish and German follow the first Windows UI-language preference.
Every other UI language falls back to English. Windows timezone and time
format are used. Unsupported text is rejected instead of being echoed in an
error. All application resources and messages follow the same text policy.
The application contains no audio assets and calls no sound playback API.
Errors are shown in the status strip. Native edit-control alert paths are
handled silently. Isovela does not display notification balloons or modify
the operating system's global audio settings.


Signed by Carman Tew. Current downloads: https://rosennavideo.com/#desktop