WebP — Google Web Image Format
Open BetaWebP is Google's open raster format built on the VP8 video codec (lossy) and its VP8L extension (lossless). On osm2cdr.ru the map is rendered to PNG and then transcoded to WebP via Pillow. In lossy mode the file is 25–35% lighter than JPEG; in lossless mode 26% lighter than PNG. WebP supports transparency and works in every mainstream browser. It is a finished map image, not editable layers — a handy lightweight format for previews and thumbnails, but not a replacement for GeoTIFF in full-size cartographic export.
Tính năng chính
Giới thiệu về định dạng WebP
WebP is Google's raster format, grown out of the VP8 video codec. It works in two modes: lossy, when weight matters, and lossless, when pixel accuracy matters. Transparency is supported by both modes, and WebP is displayed by every current browser.
For maps this is a screen format: a preview in a catalog, a picture in an article, an asset in a mobile app. Where PNG weighs more than it should and JPEG blurs thin road lines and labels, WebP gives a reasonable compromise between weight and readability.
The map is rendered to PNG and then re-encoded into WebP: lossy mode and quality 80 by default, or lossless mode with exact pixel reproduction if you prefer. This is a finished image: layers are not editable and there are no coordinates inside. For a print house take TIFF or PDF, for a GIS — GeoTIFF.
Chương trình nào mở được tệp WebP
Các chương trình và ứng dụng sau có thể mở, chỉnh sửa và làm việc với tệp WebP — Google Web Image Format (.webp) được xuất từ OSM2CDR:
Format specifications
- Open standard
- 2D only
- Lossy compression
- No attributes
- Output: 1 file
- A single WebP transcoded from PNG via Pillow; lossy VP8 by default (~25-35% lighter than JPEG) with an optional lossless VP8L mode, alpha supported.
Ai sử dụng bản đồ WebP
Cách xuất WebP
Cách mở tệp sau khi xuất
- A browser — just open the file: Chrome, Firefox, Edge and Safari 14 and newer display WebP without plugins.
- A web page — <picture><source srcset="map.webp" type="image/webp"><img src="map.png" alt="map"></picture>: older clients will get the fallback PNG.
- GIMP, Affinity Photo, Photoshop 2022 and newer — they open and save WebP; handy for cropping the picture or adding a caption.
- ImageMagick or cwebp — re-encode to your own requirements: magick map.webp -quality 70 out.webp, or cwebp -lossless for exact pixel reproduction.
- Not for print — this is an RGB picture for the screen; for a print house take TIFF, CMYK TIFF or PDF.
Bản đồ phổ biến ở định dạng WebP
Nhận bản đồ xuất ở định dạng WebP — Google Web Image Format
Tải bản đồ WebP chuyên nghiệp từ OpenStreetMap. Tạo tức thì, bất kỳ khu vực nào.