レッスン 4
PNG Output and Print Quality 日本語ガイド
日本語の qr code png output and print quality ガイド: Size, contrast, quiet zone, and raster output.
このコンテンツはまだ日本語で用意されていません。ローカライズが完了するまで English 版を表示しています。
Most browser-side generators export PNG—a raster image. That is fine for slides, PDFs, and many print workflows if you respect a few physical constraints.
Output size (pixels)
Larger PNGs give printers and projectors more modules per inch when downscaled. For a sticker or slide:
- Prefer 256px–512px exports for on-screen use
- For small print, export larger than the final printed size, then let the layout tool scale down—never upscale a tiny PNG
Contrast
Scanners need clear dark/light separation:
- Dark foreground on light background is the safest default
- Light-on-dark can work on screens but fails more often in print and glare
- Brand colors are fine if contrast remains strong—test, do not assume
Quiet zone (margin)
Leave blank space around the code. Crowding the symbol against text, borders, or logos reduces successful scans even with high error correction.
PNG vs vector
PNG is pixels; SVG (when available) scales cleanly for large-format print. For DevCove's generator, PNG is the primary export—treat it as a final asset at the target display size or export oversampled for print.
Key takeaway
Size, contrast, and margin matter as much as error correction. Export, place at final size, and scan once in the target medium before mass production.