GuoheView

Extensions

The GuoheView app itself is only about 4M. So that nobody pays in size for features they don't use, some capabilities ship as optional plugins: the app works fine without them, and once installed they are available after a restart.

Plugins live in the plugins folder inside the program folder, in one subfolder per type:

GuoheView.exe
plugins\
  decoder\    Decoder plugins (more image formats)
  ocr\        Text recognition plugin (OCR)

For the installer edition the program folder is C:\Program Files\GuoheView by default; for the portable edition it is the folder you extracted. Both subfolders already exist after installing / extracting, each with a readme.txt inside.

All plugins are available from the download page. They are provided separately and are not bundled with the app.

Decoder plugins

These extend the image formats you can open. The app already has almost all common and professional formats built in; a few formats ship as plugins for size or licensing reasons, JPEG XL for example.

Installation

  1. On the download page, under "Plugin downloads → Decoder plugins", download the plugin you need (for example jxl.7z).
  2. Extract it and put the .dll file inside into plugins\decoder\ in the program folder.
  3. Restart GuoheView, and images in that format will open.

After installation the folder looks roughly like this:

plugins\decoder\
  jxl.dll
  readme.txt

Thumbnails in Explorer too

Decoder plugins also work for the thumbnail extension. After installing a plugin, go to "Settings → Thumbnails" and tick the matching extension (such as .jxl), and those files will show thumbnails in Explorer as well.

Uninstalling

Delete the corresponding .dll to turn that format off; the app and other plugins are not affected.

Text recognition (OCR) plugin

Adds text recognition in images: recognition runs on your computer, and images are never uploaded. Results are shown with the image on the left and the text on the right; you can drag across the image to select and copy text, or select text on the right — the selections on both sides stay in sync.

The engine is RapidOCR (PP-OCRv3 Chinese/English models), which handles mixed Chinese and English, vertical text and tilted text. Because it includes model files, the whole plugin package is about 20M, so it is not bundled by default.

Installation

  1. On the download page, under "Plugin downloads → Text recognition (OCR) plugin", download the plugin archive.
  2. Extract it into plugins\ocr\ in the program folder. The archive already contains the plugins\ocr\ folder structure, so extracting it straight into the program's root folder also works.
  3. Restart GuoheView.

After installation the folder should look like this:

plugins\ocr\
  gv-ocr.dll
  onnxruntime.dll
  models\
    ch_PP-OCRv3_det_infer.ort
    ch_PP-OCRv3_rec_infer.ort
    ch_ppocr_mobile_v2.0_cls_infer.ort
    ppocr_keys_v1.txt
  readme.txt

If the models folder or any .ort file is missing, recognition will fail to start.

Using it

After installing and restarting, an "OCR" badge appears in the top-right of the main window, to the left of the image counter. Click it to open the recognition window, which recognizes the current image at the highest resolution available.

In the recognition window:

  • Image on the left: drag across text to select it, double-click to select a word, triple-click to select a whole line; Ctrl+C copies the selection
  • Recognized text on the right: drag to select across lines, and Ctrl+C works here too; click "Copy All" to grab everything at once
  • Selections stay in sync: whichever line you select on the image is selected on the right, and vice versa
  • The toolbar contains, in order: Recognize Again, Fit Window, Actual Size, Rotate 90°, and Copy All on the far right
  • The status bar at the bottom shows the recognition time and line count; it also notes when a very large image was downsampled

While the recognition window is open the main window is paused. Close it (Esc or the close button in the top-right) to go back to browsing.

Turning it on and off

Go to "Settings → Extensions" to see the plugin status:

  • Installed: a "Show on main window" switch; turn it off and the main window no longer shows the "OCR" badge
  • Not installed: a link to download it from the website

About recognition quality

Results come from model inference and are not 100% accurate, especially for decorative fonts, very small text, or busy backgrounds. The app automatically filters out obvious garbage lines (very low confidence, lines made entirely of symbols, etc.), so sometimes an area of the image that "looks like text" has no result — that is usually a misrecognition that was filtered out.

Uninstalling

Delete the files in plugins\ocr\ to turn it off; the app hides the OCR entry automatically.

FAQ

I installed a plugin but nothing happens? First make sure you restarted the app — plugins are only loaded at startup. Then check the files are in the right place: plugins\decoder\ or plugins\ocr\ inside the program folder, not the root of plugins\.

Can I use plugins with the portable edition? Yes. The portable and installer editions have exactly the same plugin folder structure; just extract into the portable folder.

Will plugins be lost when I update the app? No. Updates only replace the app's own files; the plugins folder is not touched.

Do plugins go online? No. Decoder plugins only decode locally, and the OCR plugin's models also run on your computer — images are never uploaded to any server.