Unless otherwise noted, the
*.gzfiles were generated by the
gzip command line tool and the
*.zlib versions were then generated by
script/extract-deflate-offsets.go. Similarly, the
*.giflzw files were generated by
script/extract-giflzw.go and the
*.indexes files were generated by
*.tokens files were generated by
*.jpeg files are usually the canonical versions of the test/data images, and other versions (
*.png etc) were usually generated by ImageMagick's
convert command line tool. The
*.wbmp versions were generated by the
script/convert-png-to-wbmp.go command line tool. The
*.webp versions were generated by the cwebp command line tool. The
*.no-ancillary.png files were generated by the
script/strip-png-ancillary-chunks.go command line tool.
*.apng files were generated by
gif2apng. Those with finite animation loop counts were manually patched to correct for a
gif2apng bug. https://bugs.chromium.org/p/chromium/issues/detail?id=592735 argues that GIF and APNG/WEBP have different semantics but
gif2apng does not cater for that.
artificial-* directories hold artificially generated test data, often to explicitly test corner cases of various file formats. The files there usually come in families whose names have a common prefix, such as three files
foo.bar.commentary.txt all prefixed by
foo.bar. The file whose name is that prefix is usually the canonical (typically hand-crafted) file, and the other files are then derived from that. Outside of the
artificial-* directories, the other files in this directory are typically real world examples of various file formats, or deriviations of them.
The non-ascii directory holds trivial UTF-8 (but not ASCII) text files.
DCI-P3-D65.icc comes from color.org.
DCI-P3-D65.icc.zlib is a zlib-compresion of that, created by Go's standard library.
archive.* archives a subset of other files in this directory.
animated-red-blue.gif is an original animation by Nigel Tao email@example.com.
animated-red-blue.*.nie were then generated by
australian-abc-local-stations.json was crawled from data.gov.au.
bricks-* are various encodings of an original photo by Nigel Tao firstname.lastname@example.org.
cbor-rfc-7049-examples.cbor is the concatenated examples from RFC 7049. The
cbor-rfc-7049-examples.*.json files were then generated by
checkerboard.*.png was generated by
crude-flag.* is an original animation by Nigel Tao email@example.com. See the
file-sizes.json was created by running
script/print-file-sizes-json.go in this repository's root directory.
gifplayer-muybridge.gif is an original animation by Nigel Tao firstname.lastname@example.org.
harvesters.* are various encodings of a photo of “The Harvesters” by Pieter Bruegel the Elder, held by the Metropolitan Museum of Art. www.metmuseum.org lists that image as in the public domain.
github-tags.json was crawled from api.github.com.
hat.* are various encodings of a photo of “Self-Portrait with a Straw Hat (obverse: The Potato Peeler)” by Vincent van Gogh, held by the Metropolitan Museum of art. www.metmuseum.org lists that image as in the public domain.
hello.sh is a trivial shell script.
hibiscus.regular.* are various encodings of a photo of “Hibiscus and Parrots” by Louis Comfort Tiffany, held by the Metropolitan Museum of Art. www.metmuseum.org lists that image as in the public domain.
hibiscus.primitive.* is the result of running the
hibiscus.regular.png image through
github.com/fogleman/primitive and other programs:
primitive -i hibiscus.regular.png -o hibiscus.primitive.svg -s 442 -n 32
inkscape -z -e hibiscus.primitive.png hibiscus.primitive.svg
hippopotamus.* are various encodings of a cropping of a photo of “Hippopotamus (William)”, held by the Metropolitan Museum of Art. www.metmuseum.org lists that image as in the public domain.
www.metmuseum.org says that “You are welcome to use images of artworks in The Met collection that the Museum believes to be in the public domain, or those to which the Museum waives any copyright it might have, for any purpose, including commercial and noncommercial use, free of charge and without requiring permission from the Museum.”
json-things.* are original JSON objects by Nigel Tao email@example.com.
midsummer.txt is an excerpt of Shakespeare‘s "A Midsummer Night’s Dream", copied from shakespeare.mit.edu.
muybridge.gif is derived from en.wikipedia.org which is in the public domain.
nobel-prizes.json was crawled from api.nobelprize.org.
pi.txt contains the digits of pi.
pjw-thumbnail.* are various encodings of an image derived from an iconic, original photo of Peter J. Weinberger by Rob Pike firstname.lastname@example.org.
red-blue-gradient.*.png was generated by
rgb24png.bmp comes from BMP Suite, which states that its generated images “are in the public domain”.
romeo.txt is an excerpt of Shakespeare's “Romeo and Juliet”, copied from shakespeare.mit.edu.
romeo.txt.fixed-huff.deflate was derived from
romeo.txt by a custom program to use fixed (not dynamic) Huffman tables for the deflate encoding.
sheep-more.rac is a RAC-compression of original text by Nigel Tao email@example.com.