Unless otherwise noted, the \*.gz files were generated by the gzip command line
tool and the \*.deflate and \*.zlib versions were then generated by
script/extract-deflate-offsets.go. Similarly, the \*.giflzw files were
generated by script/extract-giflzw.go and the \*.palette and \*.indexes files
were generated by script/extract-palette-indexes.go

The \*.jpeg files are usually the canonical versions of the test/data images,
and other versions (\*.bmp, \*.gif, \*.png, \*.tiff) were generated by
ImageMagick's convert command line tool. The \*.webp versions were generated by
the cwebp command line tool.



The artificial directory holds 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", "foo.bar.qux", "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 directory, the other files in this directory are typically real
world examples of various file formats, or deriviations of them.



animated-red-blue.gif is an original animation by Nigel Tao
<nigeltao@golang.org>.

bricks-\* are various encodings of an original photo by Nigel Tao
<nigeltao@golang.org>.

crude-flag.\* is an original animation by Nigel Tao
<nigeltao@golang.org>. See the `lib/nie` documentation.

gifplayer-muybridge.gif is an original animation by Nigel Tao
<nigeltao@golang.org>.

harvesters.\* are various encodings of a photo of "The Harvesters" by Pieter
Bruegel the Elder, held by the Metropolitan Museum of Art.
`http://www.metmuseum.org/art/collection/search/435809` lists that image as in
the public domain.

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. `http://www.metmuseum.org/art/collection/search/436532` lists
that image as in the public domain.

hibiscus.regular.\* are various encodings of a photo of "Hibiscus and Parrots"
by Louis Comfort Tiffany, held by the Metropolitan Museum of Art.
`http://www.metmuseum.org/art/collection/search/13503` 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`
  - Various invocations of `convert` and `cwebp`

hippopotamus.\* are various encodings of a cropping of a photo of "Hippopotamus
(William)", held by the Metropolitan Museum of Art.
`http://www.metmuseum.org/art/collection/search/544227` lists that image as in
the public domain.

`http://www.metmuseum.org/about-the-met/policies-and-documents/image-resources`
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."

midsummer.txt is an excerpt of Shakespeare's "A Midsummer Night's Dream",
copied from `http://shakespeare.mit.edu/midsummer/midsummer.1.1.html`

muybridge.gif is derived from
`https://en.wikipedia.org/wiki/File:Muybridge_race_horse_animated.gif` which is
in the public domain.

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 <r@golang.org>.

romeo.txt is an excerpt of Shakespeare's "Romeo and Juliet", copied from
`http://shakespeare.mit.edu/romeo_juliet/romeo_juliet.2.2.html`

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.