[rohitLovesKrishna]

2026-11-03.19-49-47_compressed.mp4

Hi @KnifeLemon,

This PR adds offline AI image upscaling and super-resolution (up to 4x) using local Vulkan/NCNN neural network models, bringing high-fidelity local image enhancement to Filee while strictly upholding Filee's offline privacy promise.

What this adds

1. 100% Offline AI Super-Resolution Engine (Filee.Engines.Upscale):

   • Executes entirely on the local machine via Vulkan GPU acceleration or CPU mode using upscayl-bin (NCNN).
   • Never makes network connections during inference; all computation is in-process/local child process.
   • Probes hardware capabilities automatically (Vulkan GPU adapter detection with graceful CPU fallback and recommendations).
   • Supports 1x to 4x scaling across all standard image formats: PNG, JPG, JPEG, WEBP, ICO, HEIC, AVIF, BMP, and TIFF.

2. Curated Model Catalog (UpscaleModelInfo):

   • Curated list of 10 image-focused super-resolution models from open-source projects (upscayl/custom-models):
     • CPU & iGPU friendly: 4xLSDIRCompactC3, RealESRGAN_General_x4_v3, RealESRGAN_General_WDN_x4_v3.
     • Dedicated GPU / High Fidelity: 4x_NMKD-Siax_200k, 4x_NMKD-Superscale-SP_178000_G, 4xLSDIR, 4xLSDIRplusC, 4xNomos8kSC, 4xHFA2k, uniscale_restore.
   • Models are stored locally in %LOCALAPPDATA%\Filee\engines\upscaler-models\.

3. Engines Page Integration (Settings → Engines):

   • Added an Image Quality Models card with status indicator and a Download Models button.
   • Opens the dedicated UpscaleModelManagerWindow:
     • Real-time search filter.
     • Individual download progress bars and size indicators.
     • Single-click "Download Recommended" for compact models.
     • Safe deletion with destructive confirmation prompt (WindowService.ConfirmAsync) and localized error handling.

4. Donut Wheel & Interactive Workflow (UpscaleWindow):

   • Added an Upscale preset slice to image profiles with clean font sizing (≤ 11.0 px) so text never clips.
   • Interactive modal opens on trigger:
     • Model selection dropdown with model sizes and target descriptions.
     • Scale slider (1x to 4x).
     • Live resolution preview: e.g. 300 x 400 px → 1200 x 1600 px (4x).
     • Output format choices (keep source format or convert to png/jpg/webp/ico).
     • Persistent Upscale Now button in the footer for quick comparisons, with an inline Open Folder button in the success card.

5. Presets Page & Preset Editor (Settings → Presets):

   • Registered "tool-upscale" (UpscaleTool) so it can be managed and configured in Settings.
   • PresetEditorView displays an Upscale options card allowing users to configure default models and scales with full model descriptions and a shortcut to the model manager.

6. Localisation & Attribution:

   • Strictly additive keys across all 19 language files (src/Filee.App/Assets/i18n/*.json), maintaining exact formatting conventions (it.json non-indented, Korean in standard polite ~해요 tone).
   • Full license attribution added to THIRD-PARTY-NOTICES.md for upscayl-bin / upscayl-ncnn and Upscayl Custom Models.
   • Documented in docs/ENGINES.md under ## Image Quality Models (Offline AI Upscaler).

Tests & Verification

• Added 20 automated unit tests in tests/Filee.Engines.Tests/UpscalerTests.cs verifying catalog metadata, GPU detection heuristics, argument generation, CLI path resolution, cancellation tokens, and full upscale cycles.
• dotnet test passing (20/20).
• dotnet format --verify-no-changes --severity warn clean with 0 warnings.
• Rebased on top of upstream/main (d4d4c066) with zero conflicts.

[KnifeLemon]

Thanks, @rohitLovesKrishna. Offline AI upscaling is a good fit for Filee: it runs locally, nothing leaves the PC, and the model choice with its live size preview is well thought out. The direction is good. Before it can merge, a few parts need to follow how Filee already handles engines, downloads and presets.

Timing: the next release is planned for around 17:00 UTC today (November 3). To make it into that release, the changes below would need to be pushed by 16:20 UTC. If that's too tight (it's a big PR), no problem: it goes into the following release.

Must fix

1. Pin every download with a SHA-256

UpscaleModelService downloads an executable (upscayl-bin) and ten models without checking what arrives. The models also come from the main branch of upscayl/custom-models, which can change at any time. Every other engine Filee downloads is pinned by version and SHA-256:

• programs in src/Filee.Engines/Infrastructure/engines.json, installed by EngineInstaller;
• per-item data (the Tesseract languages) in ocr-languages.json, with a URL pinned to a tag or commit and a SHA-256 per file.

Please do the same:

• The binary: add upscayl-bin as an engine package (one component per platform) in engines.json.
• The models: add an upscale-models.json pinned to a commit of custom-models (not main), with the size and SHA-256 of each .bin and .param.

2. Use the existing engine installer, not a second one

The new download service and model-manager window duplicate EngineInstaller and Settings → Engines. As a package there, the upscaler gets what the rest already has:

• the install / remove / update buttons and their progress;
• locking against a second Filee;
• clean removal of an engine in use, and no leftover .part files (#1058);
• the busy message in every language;
• filee engines on the command line.

The models can then work like the OCR languages: downloaded on first use, or from a small list in the engine's card.

3. Run the program through ProcessRunner

UpscalerEngine builds one argument string ($"-i \"{actualInput}\" …") and starts Process itself. Please use ProcessRunner.RunAsync with an argument list instead. It escapes each argument (a path with a quote in it breaks today's string), and it applies a time limit, cancellation that ends the whole process tree, lower priority and captured output.

Also:

• Work folder: put the temporary PNGs in step.WorkDirectory, not Path.GetTempPath(). The job cleans its work folder up; the system temp folder keeps whatever a crash leaves.
• Thread safety: outputLines is a plain List written from two output threads.

4. Read pictures with ImageReader

new MagickImage(inputPath) skips what ImageReader.Read does for camera RAW, layered PSD/XCF, HEIC, LIVP, KRA and the rest. Please read the source through it (with ImageEncoder.SelectFrames), as the other picture tools do.

5. Licences, per model

• upscayl-bin: it's AGPL-3.0. That's fine as a separate program downloaded on demand, which is how Ghostscript comes in. Please say so in THIRD-PARTY-NOTICES.md the same way, without the "/ BSD-3-Clause".
• The models: "various open-source licenses" isn't enough. Some upscaling models are non-commercial (CC BY-NC…), which Filee shouldn't offer as a plain download. Please list each model's licence in the catalog and in the notices, and leave out any that aren't free to use.

6. Existing users: a settings schema step

UpscalePresets() only reaches new libraries. Existing users need a migration step that adds the tool to the library, palette only, no donut slot (#806). main is at 63 (#1062), so take 64.

7. No special case in DonutMenu

The change in DonutMenu.cs makes the label smaller only when the id is tool-upscale or the text is "Upscale". Labels fit by their length in every language, so please drop this. If "Upscale" doesn't fit somewhere, the label sizing should be fixed for every slice, in its own PR.

Smaller

• ARM64: the release has windows, macos and linux zips. Please check which architectures they hold. Where there's no build (Windows ARM64, Linux ARM64), the engine should say "not available on this PC" (EngineDownloads.UnavailableReason) rather than fail.
• Tests: keep anything that needs the real program or network behind Assert.SkipUnless(...), as the other engine tests do, so CI doesn't download it.

Happy to look again as soon as it's pushed.

[rohitLovesKrishna]

Thanks for the thorough review and guidance, @KnifeLemon! All requested changes have been addressed:

1. Pinned downloads & SHA-256:

   • upscayl-bin is registered as an engine package in src/Filee.Engines/Infrastructure/engines.json across windows-x64, linux-x64, osx-x64, and osx-arm64, pinned with exact byte sizes and SHA-256 hashes.
   • upscale-models.json pins each model's .bin and .param to commit 4b6d2cfa59c7442af115dfc6e50fd8d7d40b96ef of upscayl/custom-models with individual SHA-256 checksums.

2. Existing engine installer integration:

   • Removed the duplicate UpscaleModelService and manager window. upscayl-bin is now managed like any other engine in Settings → Engines via EngineInstaller (with install/remove/update, progress, locking, and clean folder cleanup).
   • Models are managed similarly to OCR languages via UpscaleModels, downloading on first use with hash checks, temporary files, and atomic file moves. Model deletion prompts confirmation via WindowService.

3. ProcessRunner:

   • UpscalerEngine now runs via ProcessRunner.RunAsync with argument lists, stores temporary files inside step.WorkDirectory, and handles progress reporting thread-safely.

4. ImageReader integration:

   • Source pictures are loaded through ImageReader.Read and ImageEncoder.SelectFrames(..., "png"), unlocking camera RAW, PSD, XCF, HEIC, LIVP, KRA, and multipage formats for upscaling.

5. Licenses per model:

   • Removed uniscale_restore (non-commercial CC-BY-NC-SA-4.0), unknown-2.0.1, and video models.
   • Updated THIRD-PARTY-NOTICES.md with AGPL-3.0 for upscayl-bin and explicit attribution / license notices for each curated model (WTFPL, BSD-3-Clause, CC-BY-4.0).

6. Settings schema 64:

   • Schema version bumped to 64. Existing libraries have the "Upscale Image" tool added to their palette immediately after Annotate (tool-annotate) without altering any default donut profile slots.

7. DonutMenu clean-up:

   • Reverted custom label sizing in DonutMenu.cs.

8. Platform availability & Tests:

   • Linux and Windows ARM64 report as unavailable with explanatory messages.
   • Added UpscaleToolTests and guarded real execution tests in UpscalerTests with Assert.SkipUnless.

[KnifeLemon]

Thanks, @rohitLovesKrishna, a big step forward. Much of the review is done well:

• Pins: I downloaded every pinned file (the three upscayl-bin zips and all 18 model files at commit 4b6d2cfa…). Each size and SHA-256 matches, and the zips hold x64 Windows, x64 Linux and universal macOS binaries.
• ProcessRunner, ImageReader and schema 64: in place. Schema 64 is palette only, with tests, and merges cleanly with main.
• Cleanup: the non-commercial model and the DonutMenu special case are gone, and CI is green.

It won't make today's 2.3.0 release, though: a few things still need to change, one of which breaks an existing feature.

Must fix

1. Whisper is broken by the installer change. In EngineInstaller, case "model": now falls into the new ncnn-param / ncnn-bin block (on main it fell into "bin"). whisper-model has "kind": "model", so it gets a .whisper-model marker and returns early. Marker() then looks for .filee-component, so Whisper never counts as installed and re-downloads its 148 MB every time. Please keep "model" with "bin" and give the NCNN files their own kinds only. A test that installs a kind: "model" component would catch it.
2. The Windows binary needs VCOMP140.DLL, which isn't in the zip. On a PC without the VC++ Redistributable it won't start. Add the vcruntime component to the package (as Ghostscript does) and make sure that DLL is copied next to upscayl-bin.exe.
3. Upscaling isn't a real conversion step. UpscalerConverter's edges are plain DirectOnly edges with no planner flag, so a preset with Upscale.Enabled that goes through JobQueue routes via ImageMagick and is never upscaled. The window also calls UpscalerEngine itself, with its own output path, so there's no toast, no history and no output rules. Please hand the job to the conversion service like the other tools do (XTool.ConversionOf(...)), with a flag on the edge (as Translate, OCR and Captions have) so only upscale presets take it.
4. Format ids: "Same format" uses the file's extension as the format id (UpscaleViewModel.cs:214). .jpeg, .tif and camera RAW extensions then reach ImageReader.Read / ImageEncoder.ToMagickFormat, which throws. Use FormatRegistry.Detect(...).Id, and UpscaleTool.TargetFor (PNG for sources Filee can't write). The converter's format list also has "jpeg", which isn't a format id.
5. Deleting a model can crash Filee: UpscaleWindow.axaml.cs deletes in an async void handler with no try / catch. An EngineBusyException or IOException there ends the app.
6. Closing the window doesn't stop the job: the title-bar ✕ (and opening a second window) leaves upscayl-bin running hidden until its 15-minute limit. Cancel on close and dispose the view model.
7. Notices and docs: the NMKD models are by nmkd (not Philip Hofmann), and their two OpenModelDB links return 404. docs/ENGINES.md still lists uniscale_restore and the removed model manager.
8. Leftover keys: 17 keys from the removed manager window are unused in all 19 files (engines.upscaler.manage, modal_title, search_placeholder, hardware_*, recommended_*, download*, delete_*, no_models, upscale.no_models_installed, engine.reason.needs_models). Please remove them.

Smaller

• Windows on ARM: on Windows 11 ARM64 the x64 zip is offered (the runtime maps to win-x64), not "unavailable" as the PR says. Whether it runs there under emulation with Vulkan is untested, so please say which you intend.
• Scale: the binary takes 2, 3 or 4 (-s), but the UI allows 1×.
• Output: the output is written with a bare MagickImage.Write, so the preset's quality is ignored. Use the image encoder, which also handles ICO's size limit.
• Small fixes: the model download shows no progress, and the window hard-codes colours instead of theme resources.

Happy to look again for the next release.

[rohitLovesKrishna]

Thanks for the thorough review, @KnifeLemon! All points have been addressed in the latest commit:

1. Whisper installer fix: Restored case "model": to fall into case "bin": in EngineInstaller.cs so .filee-component is created and Whisper models stay installed. Added a unit test (Model_components_are_copied_and_marked_installed) in EngineInstallerTests.cs to guard against regressions.
2. VC++ runtime on Windows (VCOMP140.DLL): Added vcruntime to the upscayl-bin package on Windows in EngineDownloads.cs and updated EngineInstaller.CopyRuntime to copy runtime DLLs to zip components so vcomp140.dll sits next to upscayl-bin.exe.
3. Conversion step & JobQueue routing: Added an Upscale: true flag to ConversionEdge, RouteStep, ConversionStep, and RouteRequest. Edges are excluded from normal routes and only taken when Upscale.Enabled is set on the preset. UpscaleViewModel now delegates conversion to ConversionService.Start using UpscaleTool.ConversionOf(...), routing through JobQueue with standard toasts, history, output rules, and recycle bin support. The Upscale window also remains accessible so users can run additional conversions with other models in the same session.
4. Format IDs: Replaced file extension lookups with FormatRegistry.Detect(...).Id and UpscaleTool.TargetFor(...) (falling back to PNG for camera RAW and unwriteable formats). Removed "jpeg" from UpscalerConverter's format list.
5. Model deletion safety & UI: Wrapped model deletion in a try / catch handling EngineBusyException and IOException with an error dialog. Added the Material delete trash icon StreamGeometry resource so the delete icon displays and is functional on downloaded models.
6. Cancellation & window closing: Implemented IDisposable on UpscaleViewModel and hooked into the window's Closing event to cancel the token source on close or when opening another window, terminating any running upscayl-bin process.
7. Scale factor & output encoding: Restricted scale factor to 2×, 3×, and 4×. Replaced bare MagickImage.Write with ImageEncoder.ApplyOptions and ImageEncoder.WriteImage to respect preset image quality and ICO constraints.
8. Theme resources & download progress: Replaced hardcoded hex colors with dynamic theme resources ({DynamicResource SuccessBrush}, {DynamicResource DangerBrush}, etc.) and added progress percentage feedback during model downloads.
9. Docs & Notices: Updated NMKD models author to nmkd in THIRD-PARTY-NOTICES.md (and removed dead links). Removed uniscale_restore and references to the old manager window in docs/ENGINES.md. Clarified Windows on ARM behavior.
10. i18n cleanup: Removed all 17 unused leftover keys across all 19 language files while maintaining formatting and it.json styling.

[KnifeLemon]

Thanks, @rohitLovesKrishna. A lot of this is much better now: everything in the first review is done, the schema step (v69) sits cleanly on main's 68, the zip pins match, the arguments use list form, and all 22 keys are in all 20 languages. CI is green too, but these need fixing, because CI can't reach any of them.

Must fix

1. VCOMP140.DLL is still not installed (EngineDownloads.cs:57)

This is the one from my last review. vc14_runtime leaves it out on purpose: conda-forge's packaging skips vcomp*.dll, and the package depends on vcomp14 for it. So on a PC without the VC++ Redistributable, upscayl-bin won't start. Add vcomp14 (the -h818238b_41 build that goes with the runtime you pin) and copy it in CopyRuntime.

2. Portrait photos come out sideways (UpscalerEngine.cs:52-58)

The frame is written to the temp PNG without AutoOrient, and ImageReader doesn't rotate. PNG has no orientation for ApplyOptions to see later, so a phone's portrait JPEG ends up on its side. EXIF and ICC are dropped there too, whatever KeepMetadata says. Please orient first and copy the profiles to the result.

3. The default "Same format" fails for many pictures (UpscaleTool.cs:29, UpscalerConverter.cs:13)

TargetFor returns any writable format, but the converter has edges for only 8. GIF, JXL, TGA, JP2 and PSD are writable, get their own id back and end in error.no_route. Fall back to PNG unless the id is one of the targets, or add the edges.

4. The window says it worked before anything ran (UpscaleViewModel.cs:214-221)

_start only enqueues, and straight after it the window shows upscale.success, even if the job fails later. Clicking again queues the same pictures again. Please close the window after starting and let the toast report the result.

5. Removing Upscayl can break Ghostscript's status (EngineDownloads.cs:57, EngineInstaller.cs:174)

vcruntime is now shared. Removing one package moves that folder away, so IsInstalled for the other turns false, and Ghostscript shows as not installed (and the other way round). Components that another installed package still uses have to stay.

6. No Vulkan means raw English stderr (UpscalerEngine.cs:93, docs/ENGINES.md:1919)

From its source (main.cpp:1193), upscayl-bin has no CPU mode: with no Vulkan device it exits -1. The user then sees its stderr untranslated, and the docs still claim a CPU route. Refuse with a translated ConversionRefusedException and correct the docs.

Smaller

• UpscaleViewModel.cs:114: common.files_count doesn't exist, so several pictures show the raw key. home.files is the one.
• PresetEditorView.axaml:302: the slider allows 1×, which saves 1 and reopens at 4×. Minimum 2.
• UpscalerEngine.cs:48-49: fixed temp names in the job's work folder. If a later file exits 0 without output, it gets the previous file's picture. Use unique names.
• UpscalerEngine.cs:17: a 15-minute total limit can kill slow runs that are still working. A stall timeout fits better, like calibre's.
• upscale-models.json:10,25: the author still says "Philip Hofmann (NMKD)", from the last review.
• Unused: GpuId (Preset.cs:1700) and upscale.processing in the language files.
• Comments say schema 65 (BuiltInData.cs:334,338, Preset.cs:285, UpscaleToolTests.cs:2).
• Unrelated to this PR: ClipWindowTests.cs:919 triples a wait, and there are stray blank lines in AppHost.cs, EnginesPageViewModel.cs and EnginesPage.axaml.cs.
• UpscalerTests: Assert.NotNull(status) proves nothing. Items 2 and 3 and the PNG fallback need real tests.

Question still open

Is Windows on ARM meant to work? Please say either way, so we know whether it needs a refusal or an arm64 build.

Most of this was found by reading the code, not by running upscayl-bin, so tell me if something behaves differently on your machine.

[rohitLovesKrishna]

2026-11-04.20-14-31_compressed.mp4

Thanks for the thorough review, @KnifeLemon! All points have been addressed in the latest commit:

Must Fix

1. vcomp14 & VCOMP140.DLL:
   • Pinned vcomp14 (14.44.35208-h818238b_41) from conda-forge in engines.json and added it to upscayl-bin's Windows components in EngineDownloads.cs.
   • Updated CopyRuntime in EngineInstaller.cs to copy DLLs from both vcruntime and vcomp14 next to upscayl-bin.exe.
2. Portrait Orientation & Profile Preservation:
   • Applied frame.AutoOrient() before writing the temporary input PNG in UpscalerEngine.cs.
   • Preserved EXIF and ICC profiles from the input and re-attached them to the upscaled result according to preset.Image.KeepMetadata / KeepColorProfile, stripping old thumbnails to avoid stale orientation.
3. Target Format Fallback:
   • In UpscaleTool.TargetFor, checked against the 8 supported target IDs (png, jpg, webp, avif, heic, ico, bmp, tiff); non-target writable formats (GIF, JXL, TGA, JP2, PSD, camera RAWs) now cleanly fall back to "png".
   • Connected UpscalerConverter.Edges from all readable image sources (ImageEncoder.Sources) to the 8 supported target formats.
4. Dialog Enqueue & Close Behavior:
   • UpscaleViewModel now invokes a CloseRequested event immediately upon enqueueing conversions to ConversionService, letting the toast report the background conversion progress and completion. Removed premature success banner.
5. Shared Component Retention on Uninstall:
   • EngineInstaller.Uninstall now inspects other installed packages and leaves shared components (such as vcruntime) intact when another installed engine still depends on them.
   • Added a unit test in EngineInstallerTests.cs verifying shared component retention across multiple packages.
6. Vulkan GPU Refusal & Documentation:
   • Added check for missing DLLs (AppLocalRuntime.ThrowIfMissing) and caught exit code -1 / Vulkan device initialization errors, cleanly throwing ConversionRefusedException("error.upscale_needs_vulkan"). Added the localized message across all 20 language files.
   • Updated docs/ENGINES.md to remove references to CPU mode / donut placement, clarifying the direct Vulkan GPU requirement and palette placement.

Smaller Items & Cleanups

• Changed common.files_count to home.files in UpscaleViewModel.cs:114.
• Set slider minimum to 2 in PresetEditorView.axaml:302.
• Used unique temp file names (Guid.NewGuid()) in UpscalerEngine.cs and cleaned them up in a finally block.
• Replaced fixed 15-minute timeout with stallTimeout: StallTimeout (5-minute inactivity limit).
• Updated author to "Philip Hofmann" in upscale-models.json.
• Removed unused GpuId from Preset.cs and unused upscale.processing key across all 20 language files.
• Updated schema comment references from 65 to 69 in BuiltInData.cs, Preset.cs, and UpscaleToolTests.cs.
• Reverted out-of-scope edits in ClipWindowTests.cs, AppHost.cs, EnginesPageViewModel.cs, and EnginesPage.axaml.cs.
• Added unit tests in UpscalerTests.cs covering AutoOrient, profile preservation, and format fallback.

---

Regarding Windows on ARM (win-arm64):

upscayl-bin should be reported as unavailable on win-arm64:

• The upstream project publishes x64 binaries only for Windows (there is no native Windows ARM64 build).
• While Windows 11 on ARM provides an x64 emulation layer (Prism), the Qualcomm Adreno Vulkan driver (vulkan-1.dll / ICD) is native ARM64 only. The emulation layer does not support x64-to-ARM64 Vulkan ICD thunking, so vkCreateInstance fails during process startup.
• In EngineDownloads.cs, upscayl-bin is now restricted on Windows to non-ARM64 architectures (RuntimeInformation.ProcessArchitecture != Architecture.Arm64), cleanly reporting Upscale is not available on this PC (win-arm64).

[KnifeLemon]

Thanks, @rohitLovesKrishna. This round fixed a lot: the vcomp14 pin matches conda-forge's size and hash, portrait photos stay upright, the window closes after starting, shared components stay on removal, and Whisper still installs. All 22 keys are in all 20 languages, and your answer on Windows on ARM settles that question. A few things still need work, and CI can't reach them.

The merge conflict is on us: main is at schema 70 now, so I'll push the renumber to 71 and the matching test change. Please don't spend time on that part.

Must fix

1. HEIC output always fails (UpscalerEngine.cs:142, UpscaleTool.cs:15, UpscalerConverter.cs:17)

ImageEncoder.WriteImage writes through ImageMagick, which has no HEVC encoder. That's why HeicWriter exists. I ran the same steps with a stand-in for upscayl-bin and got no encode delegate for this image format 'HEIC'. With the default "Same format", a phone's HEIC photo goes through the whole GPU run and then fails.

The simplest fix is to remove heic from the targets, so HEIC falls back to PNG like the other formats, and update the tests and the docs. If you'd rather keep HEIC output, upscale to PNG and let the FFmpeg png → heic step write it.

2. Windows on ARM shows Upscayl as installed (EngineDownloads.cs:57, EngineInstaller.cs:129)

The empty component list means IsInstalled and IsUpToDate are true, because All() on nothing is true. I checked: Status=Installed, CanDownload=False. So the card says Installed with a Remove button, filee engines agrees, and the window tells the user to install it.

Please make an empty package not count as installed, and add a test.

3. The Vulkan refusal only works in part (UpscalerEngine.cs:107-114)

• Linux and macOS: with no usable device, upscayl-bin prints Invalid GPU Device and returns -1. On Unix the exit code is 255, and none of the four strings match that text, so the user still sees raw English. Please check for Invalid GPU Device, and for exit code 255 as well as -1.
• Successful runs: the stderr check also runs when the exit code is 0, and -v prints the temp paths there. A run that worked is refused if a driver warning or a folder name contains "vulkan". Please only look at stderr after a failure.

A small method that takes the exit code and stderr would also be easy to test.

4. Unrelated changes in the language files

All 20 files lost their blank separator lines (250 lines) and had lines re-indented (198). Please restore them, so this PR only adds its keys and doesn't collide with every other language PR. The removed note on v64 in UserDataStore.cs:1003 can come back too.

5. Tests that test something (UpscalerTests.cs)

• :179-180: Assert.NotNull(status) is still there and proves nothing.
• :102-145: this test calls Magick, not UpscalerEngine. Removing AutoOrient from the engine wouldn't fail it, and it never looks at the result. Please move the steps around the program into methods the test can call, and check the written file.
• Please add a test that CopyRuntime puts the DLLs of both vcruntime and vcomp14 next to a zip component's program.

6. Attribution

• upscale-models.json:10,25: the two NMKD models should say nmkd. They aren't by Philip Hofmann, and the notices already say nmkd.
• THIRD-PARTY-NOTICES.md:84: vcomp14 isn't listed, and the runtime line only mentions Ghostscript.

Smaller

• UpscalerEngine.cs:59-63: a multi-page TIFF silently loses every page but the first. Upscale each page, or refuse with a reason.
• UpscalerEngine.cs:133-138: a CMYK picture ends up as sRGB pixels tagged with its CMYK profile. Only copy the profile back when its colour space matches.
• UpscaleViewModel.cs:133-134: for a GIF the label says "Same format as source (gif)", but it writes PNG. Use TargetFor for the label.
• EngineInstaller.cs:288: locks are per package, but vcruntime is now shared. The app and filee engines install running together could write the same download. Please lock shared components too.
• Unused: upscale.success in the language files, IsCompleted, and _logger in UpscalerEngine and UpscalerConverter.
• ko.json:1510: "필요합니다" should be "필요해요", like the rest of the file.

I found these by reading the code and running the steps around the program, not upscayl-bin itself, so tell me if something behaves differently on your machine.

[rohitLovesKrishna]

Thanks for the detailed and thorough review, @KnifeLemon! All the points have been addressed in 6d4fab59:

Must fix

1. HEIC target removed: Removed heic from UpscaleTool.Targets, UpscalerConverter.TargetFormats, and UpscaleViewModel.Targets. HEIC input files now fall back to PNG like other non-direct writable formats when using "Same format as source". Docs and tests updated accordingly.
2. Windows on ARM empty package status: IsInstalled and IsUpToDate in EngineInstaller.cs now require package.Components.Count > 0, so an empty package is neither installed nor up to date. Added An_empty_package_is_neither_installed_nor_up_to_date test.
3. Vulkan refusal: Extracted IsVulkanRefusal(int exitCode, string stderr). When exitCode == 0, it immediately returns false (ignoring any driver notes or temp paths containing "vulkan"). On failure, it checks for exit codes -1 and 255, plus "Invalid GPU Device", "no gpu device", "vulkan", "vkCreateInstance", and "failed to create instance". Added parameterized tests for exit codes and error texts.
4. Language files & schema 64 note: Restored all 20 language files to match upstream's original blank separator lines and indentation—the diff now only appends the upscale keys at the end. Restored the removed schema 64 comment in UserDataStore.cs:1004.
5. Tests:
   • Replaced Assert.NotNull(status) with assertions on status.ReasonKey and status.IsAvailable.
   • Extracted UpscalerEngine.PrepareFrame and FinishImage: AutoOrient_and_profiles_are_applied_correctly_on_portrait_image now runs through both methods and asserts on the written output file on disk.
   • Added CopyRuntime_copies_vcruntime_and_vcomp14_dlls_next_to_zip_component test in EngineInstallerTests.cs verifying both vcruntime140.dll and vcomp140.dll are copied next to the program.
6. Attribution:
   • upscale-models.json: Updated author to nmkd for both 4x_NMKD-Superscale-SP_178000_G and 4x_NMKD-Siax_200k.
   • THIRD-PARTY-NOTICES.md: Added vcomp14 and mentioned Upscayl alongside Ghostscript on line 84.

Smaller

• Multi-page TIFF: UpscalerEngine now loops over all input frames, reports progress proportionally across pages, and writes all upscaled frames into the output when saving as TIFF.
• CMYK profiles: ColorSpaceMatches(icc, upscaled.ColorSpace) ensures CMYK profiles are never tagged onto sRGB upscaled pixels. Added test ColorSpaceMatches_rejects_cmyk_profile_for_srgb.
• Target label: UpscaleViewModel now runs the first format through UpscaleTool.TargetFor(firstFormatId, BuiltInData.SameAsSource) so GIF displays "Same format as source (png)".
• Shared component locks: LockPackage now locks the package and each of its components in alphabetical order via a composite disposable to prevent deadlocks and concurrent writes.
• Cleanup: Removed unused upscale.success key from all 20 language files, removed _isCompleted/IsCompleted in UpscaleViewModel, and removed unused _logger fields in UpscalerConverter and UpscalerEngine.
• Korean wording: Changed ko.json:1510 from "필요합니다" to "필요해요".

[KnifeLemon]

Thanks, @rohitLovesKrishna. This round is very close: I checked all six must-fix items in the code and they're done. HEIC is gone from the targets, Windows on ARM no longer shows as installed, the Vulkan check handles Linux and macOS and ignores successful runs, the language files only add their keys, the tests now call the engine's own steps, and the attribution is right. I also ran the output steps with a plain PNG standing in for upscayl-bin's result: portrait photos stay upright with their EXIF, and CMYK pictures no longer keep the CMYK profile.

The merge conflict is still on us. main is at schema 71 now, so I'll push the renumber to 72 and the matching test changes. Please don't spend time on that part.

Must fix

The PR doesn't build (UpscaleViewModel.cs:59-61)

Removing _isCompleted left its [ObservableProperty] behind, right above the one for _statusMessage, so Filee.App fails with CS0579 (duplicate attribute). CI hasn't run on this branch because of the conflict, so it couldn't tell you. Please delete that line and build the app before you push.

Smaller

• UpscalerEngine.cs:124-134: multi-page TIFF to TIFF now keeps its pages, but TIFF to PNG, JPG or another target still upscales every page and writes only the first, with no message. ImageEncoder.Write already does this properly (one file per page, _p1, _p2), so handing it the output allocator would cover both cases.
• UpscalerEngine.cs:47: SelectFrames always gets "png", so an animated WebP on "Same format" comes out as a still WebP with no message. Please either keep the animation or say so.
• UpscaleViewModel.cs:173-177: on Windows on ARM the window says to install Upscayl in Settings → Engines, which isn't possible there. Please show that it isn't available on this PC.
• UserDataStore.cs:1004: the note came back as first). and main has first.), so the PR still changes that line.
• Unused: the ClearAside(EnginePackage) overload (EngineInstaller.cs:224), _executable (UpscalerConverter.cs:21), and the logger parameters in the UpscalerConverter and UpscalerEngine constructors.
• UpscalerTests.cs:218: the comment says 8 targets, and there are 7 now.

I found these by building the PR and reading the code, not by running upscayl-bin itself, so tell me if something behaves differently on your machine.

[rohitLovesKrishna]

Thanks for the thorough review @KnifeLemon ! I've addressed all the points in the latest commit:

1. Build Fix: Removed the duplicate [ObservableProperty] above _statusMessage in UpscaleViewModel.cs. Verified that Filee.App and the full solution build cleanly with 0 errors.
2. Multi-page & Animation Handling: Updated UpscalerEngine to delegate writing to ImageEncoder.Write(..., output, ...) with IOutputAllocator. This properly splits multi-page TIFFs into _p1, _p2, ... when exporting to other targets, and preserves frame delays/animations when converting between animated formats.
3. Windows on ARM: UpscaleViewModel now checks EngineDownloads.CanDownload and displays the UnavailableReason (or "engine.reason.unsupported_platform") instead of directing users to Settings when the platform is unsupported.
4. Cleanups:
   • Restored first.) in UserDataStore.cs:1004 to eliminate diff on that line.
   • Removed unused ClearAside(EnginePackage) overload in EngineInstaller.cs.
   • Removed unused _executable field and unused logger parameters from UpscalerConverter and UpscalerEngine.
   • Updated comment in UpscalerTests.cs to reflect 7 targets.
   • Verified clean formatting with dotnet format --verify-no-changes.

[KnifeLemon]

Thanks, @rohitLovesKrishna. This round is very close. It builds, and I checked every point from last time in the code. I also ran the new flow with a plain resize standing in for upscayl-bin:

• portrait photos stay upright with their EXIF;
• CMYK pictures come out right;
• multi-page TIFF writes _p1, _p2 and so on;
• animated WebP keeps its frames and timing;
• the work folder is empty afterwards, including after a failure or a cancel.

Handing the writing to ImageEncoder.Write was the right call.

The merge conflict is still on us. main is at schema 72 now, so I'll push the renumber to the next free number and the matching test changes. Please don't spend time on that part.

Must fix

Animations and long TIFFs have no limit (UpscalerEngine.cs:70-77)

Each frame is one run of upscayl-bin, and every upscaled frame stays in memory until the end. A 1000-frame 640×480 GIF at 4× means a thousand model loads and about 20 GB of pixels.

Please refuse this before the first run, right after SelectFrames, when there are more than 300 frames, with a ConversionRefusedException and its own message in all the language files. error.too_many_frames won't fit, because it talks about "Every Nth frame".

Smaller

• UpscaleViewModel.cs:131 and :184: on Windows on ARM the message now says the right thing, but always in English. UnavailableReason always returns its English text there, so the translated engine.reason.unsupported_platform is never used. Please show the translated key directly and remove the upscayl-bin line from EngineDownloads.cs:70.
• UpscalerEngine.cs:68-70: an animated PNG saved as .png comes out as one frame with no message, even to WebP. MagickImageConverter.cs:85 already handles this with Apng.IsAnimated, so the same check here would cover it.
• Unused: the Microsoft.Extensions.Logging usings (UpscalerConverter.cs:8-9), the two empty constructors, and ConversionStep.Upscale, which nothing reads.
• UpscalerEngine.cs:130-138: if FinishImage throws, upscaled isn't disposed. Adding it to the list before calling FinishImage fixes that.

I found these by reading the code and running a stand-in, not upscayl-bin itself, so tell me if something behaves differently on your machine.

[rohitLovesKrishna]

Thanks for the detailed review @KnifeLemon ! All feedback items have been addressed in the latest commit:

1. Max 300 Frames Refusal: Added a MaxFrames = 300 check right after SelectFrames in UpscalerEngine that throws ConversionRefusedException("error.upscale_too_many_frames", ...). Added the new error.upscale_too_many_frames key to all 20 language files.
2. Animated PNGs: UpscalerEngine now checks Apng.IsAnimated when fromFormat == "png" (matching MagickImageConverter), so animated PNGs keep all their frames when upscaling.
3. FinishImage Disposal: upscaled is now added to upscaledFrames immediately after loading so the finally block disposes it even if FinishImage throws.
4. Windows on ARM Translation: UpscaleViewModel directly uses _loc["engine.reason.unsupported_platform"] so it respects the user's selected language, and the English upscayl-bin string was removed from EngineDownloads.UnavailableReason.
5. Cleanups:
   • Removed unused Microsoft.Extensions.Logging usings in UpscalerConverter.cs.
   • Removed empty constructors from UpscalerConverter and UpscalerEngine.
   • Removed unread ConversionStep.Upscale from IConverter.cs and JobQueue.cs.
   • Verified clean formatting with dotnet format --verify-no-changes.

[rohitLovesKrishna]

HI, @KnifeLemon , is everything ok to merge this PR.

[KnifeLemon]

Thanks, @rohitLovesKrishna. I checked every point from last time and they're all done: the 300-frame refusal comes before the first run with its own message in every language, Windows on ARM now shows the translated reason, animated PNGs keep their frames, the unused code is gone, and upscaled is disposed when FinishImage throws.

As promised, I pushed the merge with main, the schema renumber to 73 (after Metadata, which main added at 72), the upscale keys for the two new languages, Persian and Bengali, and a test fix: main now checks after unpacking that a package holds its program under this OS's name, so the runtime test's fake package needed upscayl-bin on Linux and macOS. CI is green, so I'm merging.

One more thing came from main: it now reads an AVIF image sequence as avis, and the upscaler still reads it as avif, so an animated AVIF comes out as _p1, _p2 stills. I'll fix that in a follow-up PR of ours, with a test.

A few smaller things for a follow-up, none blocking:

• UpscalerEngine.cs:66-77: there's no limit on the size of the result. A 50 MP photo at 4× is about 800 MP, over 3 GB in memory before upscayl-bin's own, and 300 frames of 640×480 at 4× is still about 6 GB. A check on frames × width × height × scale², refused above 200 MP like PdfiumConverter.MaxStackedPixels, would cover both.
• UpscalerEngine.cs:59: the model is downloaded before the frame check, so a file that's refused anyway first downloads a model of up to 67 MB. Checking first would avoid that.
• UpscalerTests.cs: MaxFrames_limit_is_300 only checks the constant. Moving the check into a small static method, like PrepareFrame, would let a test feed it 301 frames.

I found these by reading the code and running the tests, not upscayl-bin itself, so tell me if something behaves differently on your machine. Thanks for sticking with this one!