Standard ZIP compressors or some online converters may accidentally rasterize vectors or strip metadata. Ensure all vector assets remain in format within the ZIP structure before renaming. 2. Sound Bitrate To maintain "extra quality" audio: files for the highest fidelity.
Ensure your ZIP doesn't contain "junk" metadata files (like .DS_Store on Mac), which can slow down the loading process.
Compress-Archive -Path ".\project.json", ".\costumes", ".\sounds" -DestinationPath "output.zip" -CompressionLevel NoCompression Rename-Item "output.zip" "final.sb3"
This method frequently fails if the ZIP file was compressed using "solid" compression or strict archiving methods (like 7-Zip's ultra-compression). Scratch can be finicky about how the internal files are stored.
❌ without unzipping first – If the ZIP contains a folder, Scratch sees MyFolder/project.json and fails. ❌ Image recompression – Resaving a PNG as JPEG inside the assets folder destroys transparency and introduces artifacts. ❌ Sound resampling – Converting a 44.1kHz WAV to 22kHz MP3 inside the ZIP reduces fidelity with no file size benefit. ❌ Altering project.json formatting – Pretty-printing (adding indents) is safe, but changing IDs or asset filenames breaks everything.
Standard ZIP compressors or some online converters may accidentally rasterize vectors or strip metadata. Ensure all vector assets remain in format within the ZIP structure before renaming. 2. Sound Bitrate To maintain "extra quality" audio: files for the highest fidelity.
Ensure your ZIP doesn't contain "junk" metadata files (like .DS_Store on Mac), which can slow down the loading process. zip to sb3 extra quality
Compress-Archive -Path ".\project.json", ".\costumes", ".\sounds" -DestinationPath "output.zip" -CompressionLevel NoCompression Rename-Item "output.zip" "final.sb3" Standard ZIP compressors or some online converters may
This method frequently fails if the ZIP file was compressed using "solid" compression or strict archiving methods (like 7-Zip's ultra-compression). Scratch can be finicky about how the internal files are stored. Sound Bitrate To maintain "extra quality" audio: files
❌ without unzipping first – If the ZIP contains a folder, Scratch sees MyFolder/project.json and fails. ❌ Image recompression – Resaving a PNG as JPEG inside the assets folder destroys transparency and introduces artifacts. ❌ Sound resampling – Converting a 44.1kHz WAV to 22kHz MP3 inside the ZIP reduces fidelity with no file size benefit. ❌ Altering project.json formatting – Pretty-printing (adding indents) is safe, but changing IDs or asset filenames breaks everything.