Hey there, let's break down why your raster-to-vector conversion seems to finish but won't load the output shapefile. From your logs, GDAL reports the process completed successfully, so the issue is likely either with the generated files, the source raster, or how QGIS is trying to load the temp output. Here's what to check step by step:

1. Verify the Generated Shapefile Files Exist & Are Complete #

First, head to the temporary folder listed in your results:
C:/Users/Ya/AppData/Local/Temp/processing_10b1eb77e9d647d793fbad6baec49774/30543f2183314e709d1b01c30ffa56ab/

Check for these three critical files (all should exist and have non-zero file sizes):

• OUTPUT.shp (the main shapefile)
• OUTPUT.shx (shape index file)
• OUTPUT.dbf (attribute table file)

If any are missing or empty, GDAL had an issue writing the full output—this could be due to temporary folder permissions or a problem with your source raster.

2. Try Manually Loading the Shapefile #

Instead of relying on QGIS to auto-load the temp output, manually add it to your project:

• Click Layer > Add Layer > Add Vector Layer
• Navigate to the temp folder and select OUTPUT.shp

This will show you a more detailed error message if QGIS can't load it (e.g., invalid geometry, corrupted attribute table).

3. Fix Issues with Your Photoshop-Exported Raster #

Photoshop TIFFs often include alpha channels or have unmarked NoData values, which can trip up Polygonize:

• Check NoData Values: Load your youdrive_countur_modified.tif in QGIS, open its Properties > Information tab. Look for a "No Data Value" entry under Band 1. If there's none, your transparent areas are probably using a DN value (like 0) that GDAL is treating as valid data.
  • Fix this with the Set NoData Value tool (search in Processing Toolbox): set the NoData value to the DN of your transparent areas (e.g., 0).
• Remove Alpha Channel: If your raster has an alpha channel, GDAL might be confused. Use the Translate (Convert Format) tool to export the raster without the alpha channel (set "Band Number(s)" to 1, and uncheck any alpha-related options).

4. Avoid Temporary Output—Use a Custom File Path #

Temporary folders can sometimes have permission issues or get cleaned up unexpectedly. Try running Polygonize again, but instead of TEMPORARY_OUTPUT, specify a permanent path on your desktop (e.g., C:/Users/Ya/Desktop/polygonized_result.shp). This ensures the files aren't deleted or restricted before QGIS loads them.

5. Validate the Source Raster with GDAL Info #

Use the GDAL Info tool (Processing Toolbox) on your input TIFF to confirm it's compatible with GDAL. Look for:

• Valid band information (Band 1 should be a gray/byte band)
• No invalid data ranges
• Correct projection information (though Polygonize works without projection, missing CRS can sometimes cause loading issues)

If you find any oddities here, re-export your raster from Photoshop with TIFF settings optimized for GIS: use 8-bit grayscale, no layers, and uncheck "Save Alpha Channels" if you don't need them.

内容的提问来源于stack exchange，提问作者Denis Or