Package 'Webp'

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Package ‘webp’ March 4, 2019 Type Package Title A New Format for Lossless and Lossy Image Compression Version 1.0 Author Jeroen Ooms Maintainer Jeroen Ooms <[email protected]> Description Lossless webp images are 26% smaller in size compared to PNG. Lossy webp images are 25-34% smaller in size compared to JPEG. This package reads and writes webp images into a 3 (rgb) or 4 (rgba) channel bitmap array using conventions from the 'jpeg' and 'png' packages. License MIT + file LICENSE URL https://github.com/jeroen/webp#readme https://developers.google.com/speed/webp BugReports https://github.com/jeroen/webp/issues SystemRequirements libwebp LazyData TRUE Encoding UTF-8 Suggests jpeg, png RoxygenNote 6.1.1 Language en-GB NeedsCompilation yes Repository CRAN Date/Publication 2019-03-04 14:10:04 UTC R topics documented: read_webp . .2 Index 3 1 2 read_webp read_webp Webp image format Description Read and write webp images into a bitmap array. The bitmap array uses the same conventions as the png and jpeg package. Usage read_webp(source, numeric = TRUE) write_webp(image, target = NULL, quality = 80) Arguments source raw vector or path to webp file numeric convert the image to 0-1 real numbers to be compatible with images from the jpeg or png package. image array of 3 dimensions (width * height * channel) with real numbers between 0 and 1. target path to a file or NULL to return the image as a raw vector quality value between 0 and 100 Examples # Convert to webp library(png) img <- readPNG(system.file("img", "Rlogo.png", package="png")) out <- file.path(tempdir(), "rlogo.webp") write_webp(img, out) # browseURL(out) # Convert from webp library(jpeg) img <- read_webp(out) jpeg <- file.path(tempdir(), "rlogo.jpeg") writeJPEG(img, jpeg) # browseURL(jpeg) Index read_webp,2 webp (read_webp),2 write_webp (read_webp),2 3.

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Exploring the .BMP File Format
Exploring the .BMP File Format Don Lancaster Synergetics, Box 809, Thatcher, AZ 85552 copyright c2003 as GuruGram #14 http://www.tinaja.com [email protected] (928) 428-4073 The .BMP image standard is used by Windows and elsewhere to represent graphics images in any of several different display and compression options. The .BMP advantages are that each pixel is usually independently available for any alteration or modification. And that repeated use does not normally degrade the image. Because lossy compression is not used. Its main disadvantage is that file sizes are usually horrendous compared to JPEG, fractal, GIF, or other lossy compression schemes. A comparison of popular image standards can be found here. I’ve long been using the .BMP format for my eBay and my other phototography, scanning, and post processing. I firmly believe that… All photography, scanning, and all image post-processing should always be done using .BMP or a similar non-lossy format. Only after all post-processing is complete should JPEG or another compressed distribution format be chosen. Some current examples of my .BMP work now do include the IMAGIMAG.PDF post-processing tutorial, the Bitmap Typewriterthat generates fully anti-aliased small fonts, the Aerial Photo Combiner, and similar utilities and tutorials found on our Fonts & Images, PostScript, and on our Acrobat library pages. A few projects of current interest involving .BMP files include true view camera swings and tilts for a digital camera, distortion correction, dodging & burning, preventing white punchthrough on knockouts, and emphasis vignetting. Mainly applied to uncompressed RGBX 24-bit color .BMP files.
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Download This PDF File
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