Adding upstream version 1.21.8.upstream/1.21.8

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 20 insertions, 0 deletions

diff --git a/src/image/png/testdata/pngsuite/README b/src/image/png/testdata/pngsuite/README
new file mode 100644
index 0000000..01d1d89
--- /dev/null
+++ b/src/image/png/testdata/pngsuite/README
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+The *.png and README.original files in this directory are copied from
+libpng.org, specifically contrib/pngsuite/* in libpng 1.6.26.
+
+README.original gives the following license for those files:
+
+	Permission to use, copy, and distribute these images for any purpose
+	and without fee is hereby granted.
+
+The files basn0g01-30.png, basn0g02-29.png and basn0g04-31.png are in fact not
+part of pngsuite but were created from files in pngsuite. Their non-power-of-2
+sizes makes them useful for testing bit-depths smaller than a byte.
+
+basn3a08.png was generated from basn6a08.png using the pngnq tool, which
+converted it to the 8-bit paletted image with alpha values in tRNS chunk.
+
+The *.sng files in this directory were generated from the *.png files by the
+sng command-line tool and some hand editing. The files basn0g0{1,2,4}.sng and
+ftbbn0g0{1,2,4}.sng were actually generated by first converting the PNG to a
+bitdepth of 8 and then running sng on them. basn4a08.sng was generated from a
+16-bit rgba version of basn4a08.png rather than the original gray + alpha.