test/data: add official thumbhash PNG renderings
diff --git a/test/data/artificial-thumbhash/1QcSHQRnh493V4dIh4eXh1h4kJUI.png b/test/data/artificial-thumbhash/1QcSHQRnh493V4dIh4eXh1h4kJUI.png
new file mode 100644
index 0000000..c999054
--- /dev/null
+++ b/test/data/artificial-thumbhash/1QcSHQRnh493V4dIh4eXh1h4kJUI.png
Binary files differ
diff --git a/test/data/artificial-thumbhash/2IqDBQQnxnj0JoLYdM3f8ahpuDeHiHdwZw.png b/test/data/artificial-thumbhash/2IqDBQQnxnj0JoLYdM3f8ahpuDeHiHdwZw.png
new file mode 100644
index 0000000..8e35db5
--- /dev/null
+++ b/test/data/artificial-thumbhash/2IqDBQQnxnj0JoLYdM3f8ahpuDeHiHdwZw.png
Binary files differ
diff --git a/test/data/artificial-thumbhash/2fcZFIB3iId_h3iJh4aIYJ2V8g.png b/test/data/artificial-thumbhash/2fcZFIB3iId_h3iJh4aIYJ2V8g.png
new file mode 100644
index 0000000..202d6ee
--- /dev/null
+++ b/test/data/artificial-thumbhash/2fcZFIB3iId_h3iJh4aIYJ2V8g.png
Binary files differ
diff --git a/test/data/artificial-thumbhash/3OcRJYB4d3h_iIeHeEh3eIhw-j3A.png b/test/data/artificial-thumbhash/3OcRJYB4d3h_iIeHeEh3eIhw-j3A.png
new file mode 100644
index 0000000..7e32a7c
--- /dev/null
+++ b/test/data/artificial-thumbhash/3OcRJYB4d3h_iIeHeEh3eIhw-j3A.png
Binary files differ
diff --git a/test/data/artificial-thumbhash/3PcNNYSFeXh_d3eld0iHZoZgVwh2.png b/test/data/artificial-thumbhash/3PcNNYSFeXh_d3eld0iHZoZgVwh2.png
new file mode 100644
index 0000000..fc12c3f
--- /dev/null
+++ b/test/data/artificial-thumbhash/3PcNNYSFeXh_d3eld0iHZoZgVwh2.png
Binary files differ
diff --git a/test/data/artificial-thumbhash/HBkSHYSIeHiPiHh8eJd4eTN0EEQG.png b/test/data/artificial-thumbhash/HBkSHYSIeHiPiHh8eJd4eTN0EEQG.png
new file mode 100644
index 0000000..4e58182
--- /dev/null
+++ b/test/data/artificial-thumbhash/HBkSHYSIeHiPiHh8eJd4eTN0EEQG.png
Binary files differ
diff --git a/test/data/artificial-thumbhash/IQgSLYZ6iHePh4h1eFeHh4dwgwg3.png b/test/data/artificial-thumbhash/IQgSLYZ6iHePh4h1eFeHh4dwgwg3.png
new file mode 100644
index 0000000..13aab3b
--- /dev/null
+++ b/test/data/artificial-thumbhash/IQgSLYZ6iHePh4h1eFeHh4dwgwg3.png
Binary files differ
diff --git a/test/data/artificial-thumbhash/VggKDYAW6lZvdYd6d2iZh_p4GE_k.png b/test/data/artificial-thumbhash/VggKDYAW6lZvdYd6d2iZh_p4GE_k.png
new file mode 100644
index 0000000..e49afdd
--- /dev/null
+++ b/test/data/artificial-thumbhash/VggKDYAW6lZvdYd6d2iZh_p4GE_k.png
Binary files differ
diff --git a/test/data/artificial-thumbhash/YJqGPQw7sFlslqhFafSE-Q6oJ1h2iHB2Rw.png b/test/data/artificial-thumbhash/YJqGPQw7sFlslqhFafSE-Q6oJ1h2iHB2Rw.png
new file mode 100644
index 0000000..3628e49
--- /dev/null
+++ b/test/data/artificial-thumbhash/YJqGPQw7sFlslqhFafSE-Q6oJ1h2iHB2Rw.png
Binary files differ
diff --git a/test/data/artificial-thumbhash/make.go b/test/data/artificial-thumbhash/make.go
index e08922d..018557c 100644
--- a/test/data/artificial-thumbhash/make.go
+++ b/test/data/artificial-thumbhash/make.go
@@ -27,6 +27,16 @@
// slightly different from the base64.RawStdEncoding used on that web page)
// plus a ".th" extension.
//
+// The foobar.png files that correspond to each foobar.th file were manually
+// scraped from the https://evanw.github.io/thumbhash/ page. These PNG files
+// were written by thumbhash's original JavaScript reference implementation,
+// exercised by that page. This small JavaScript library favors implementation
+// simplicity over maximizing the compression ratio.
+//
+// For any given foobar.th input file, that library's RGBA output and Wuffs'
+// RGBA output may differ slightly, due to floating point versus fixed point
+// rounding errors, but they're pretty close.
+//
// Usage: go run make.go
import (
diff --git a/test/nia-checksums-of-data.txt b/test/nia-checksums-of-data.txt
index ac32f86..5e30d08 100644
--- a/test/nia-checksums-of-data.txt
+++ b/test/nia-checksums-of-data.txt
@@ -26,14 +26,23 @@
OK. 0564b364 test/data/artificial-png/apng-skip-idat.png
OK. e08a7cc8 test/data/artificial-png/exif.png
OK. e08a7cc8 test/data/artificial-png/key-value-pairs.png
+OK. 755ee422 test/data/artificial-thumbhash/1QcSHQRnh493V4dIh4eXh1h4kJUI.png
OK. 2b606fe3 test/data/artificial-thumbhash/1QcSHQRnh493V4dIh4eXh1h4kJUI.th
+OK. 90f3bc13 test/data/artificial-thumbhash/2IqDBQQnxnj0JoLYdM3f8ahpuDeHiHdwZw.png
OK. 70203d96 test/data/artificial-thumbhash/2IqDBQQnxnj0JoLYdM3f8ahpuDeHiHdwZw.th
+OK. 93cb6b2e test/data/artificial-thumbhash/2fcZFIB3iId_h3iJh4aIYJ2V8g.png
OK. 025631eb test/data/artificial-thumbhash/2fcZFIB3iId_h3iJh4aIYJ2V8g.th
+OK. 2160c22d test/data/artificial-thumbhash/3OcRJYB4d3h_iIeHeEh3eIhw-j3A.png
OK. 4ab0d622 test/data/artificial-thumbhash/3OcRJYB4d3h_iIeHeEh3eIhw-j3A.th
+OK. d84de1fc test/data/artificial-thumbhash/3PcNNYSFeXh_d3eld0iHZoZgVwh2.png
OK. 4ba04a51 test/data/artificial-thumbhash/3PcNNYSFeXh_d3eld0iHZoZgVwh2.th
+OK. d97db52c test/data/artificial-thumbhash/HBkSHYSIeHiPiHh8eJd4eTN0EEQG.png
OK. 5b7fd9b7 test/data/artificial-thumbhash/HBkSHYSIeHiPiHh8eJd4eTN0EEQG.th
+OK. 2a7a3f54 test/data/artificial-thumbhash/IQgSLYZ6iHePh4h1eFeHh4dwgwg3.png
OK. 69ad2c3d test/data/artificial-thumbhash/IQgSLYZ6iHePh4h1eFeHh4dwgwg3.th
+OK. c37b7991 test/data/artificial-thumbhash/VggKDYAW6lZvdYd6d2iZh_p4GE_k.png
OK. 27a6e456 test/data/artificial-thumbhash/VggKDYAW6lZvdYd6d2iZh_p4GE_k.th
+OK. d9ce0e57 test/data/artificial-thumbhash/YJqGPQw7sFlslqhFafSE-Q6oJ1h2iHB2Rw.png
OK. 4965134c test/data/artificial-thumbhash/YJqGPQw7sFlslqhFafSE-Q6oJ1h2iHB2Rw.th
OK. 076cb375 test/data/bricks-color.bmp
OK. bdbbfadb test/data/bricks-color.etc1.pkm
