png: Add test suite asset download script.

core/image/tests/.gitignore

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+*.zip
+*.png

core/image/tests/build.bat

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+@echo off
+python3 download_assets.py

core/image/tests/download_assets.py

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+#!/usr/bin/env python3
+import urllib.request
+import shutil
+import sys
+import os
+import zipfile
+
+DOWNLOAD_BASE_PATH = "assets/{}"
+ASSETS_BASE_URL    = "https://raw.githubusercontent.com/Kelimion/compress-odin/master/tests/assets/{}/{}"
+PNG_IMAGES         = [
+	"basi0g01.png", "basi0g02.png", "basi0g04.png", "basi0g08.png", "basi0g16.png", "basi2c08.png",
+	"basi2c16.png", "basi3p01.png", "basi3p02.png", "basi3p04.png", "basi3p08.png", "basi4a08.png",
+	"basi4a16.png", "basi6a08.png", "basi6a16.png", "basn0g01.png", "basn0g02.png", "basn0g04.png",
+	"basn0g08.png", "basn0g16.png", "basn2c08.png", "basn2c16.png", "basn3p01.png", "basn3p02.png",
+	"basn3p04.png", "basn3p08.png", "basn4a08.png", "basn4a16.png", "basn6a08.png", "basn6a16.png",
+	"bgai4a08.png", "bgai4a16.png", "bgan6a08.png", "bgan6a16.png", "bgbn4a08.png", "bggn4a16.png",
+	"bgwn6a08.png", "bgyn6a16.png", "ccwn2c08.png", "ccwn3p08.png", "cdfn2c08.png", "cdhn2c08.png",
+	"cdsn2c08.png", "cdun2c08.png", "ch1n3p04.png", "ch2n3p08.png", "cm0n0g04.png", "cm7n0g04.png",
+	"cm9n0g04.png", "cs3n2c16.png", "cs3n3p08.png", "cs5n2c08.png", "cs5n3p08.png", "cs8n2c08.png",
+	"cs8n3p08.png", "ct0n0g04.png", "ct1n0g04.png", "cten0g04.png", "ctfn0g04.png", "ctgn0g04.png",
+	"cthn0g04.png", "ctjn0g04.png", "ctzn0g04.png", "exif2c08.png", "f00n0g08.png", "f00n2c08.png",
+	"f01n0g08.png", "f01n2c08.png", "f02n0g08.png", "f02n2c08.png", "f03n0g08.png", "f03n2c08.png",
+	"f04n0g08.png", "f04n2c08.png", "f99n0g04.png", "g03n0g16.png", "g03n2c08.png", "g03n3p04.png",
+	"g04n0g16.png", "g04n2c08.png", "g04n3p04.png", "g05n0g16.png", "g05n2c08.png", "g05n3p04.png",
+	"g07n0g16.png", "g07n2c08.png", "g07n3p04.png", "g10n0g16.png", "g10n2c08.png", "g10n3p04.png",
+	"g25n0g16.png", "g25n2c08.png", "g25n3p04.png", "oi1n0g16.png", "oi1n2c16.png",	"oi2n0g16.png",
+	"oi2n2c16.png", "oi4n0g16.png", "oi4n2c16.png", "oi9n0g16.png", "oi9n2c16.png", "pp0n2c16.png",
+	"pp0n6a08.png", "ps1n0g08.png", "ps1n2c16.png", "ps2n0g08.png", "ps2n2c16.png", "s01i3p01.png",
+	"s01n3p01.png", "s02i3p01.png", "s02n3p01.png", "s03i3p01.png", "s03n3p01.png", "s04i3p01.png",
+	"s04n3p01.png", "s05i3p02.png", "s05n3p02.png", "s06i3p02.png", "s06n3p02.png", "s07i3p02.png",
+	"s07n3p02.png", "s08i3p02.png", "s08n3p02.png", "s09i3p02.png", "s09n3p02.png", "s32i3p04.png",
+	"s32n3p04.png", "s33i3p04.png", "s33n3p04.png", "s34i3p04.png", "s34n3p04.png", "s35i3p04.png",
+	"s35n3p04.png", "s36i3p04.png", "s36n3p04.png", "s37i3p04.png", "s37n3p04.png", "s38i3p04.png",
+	"s38n3p04.png", "s39i3p04.png", "s39n3p04.png", "s40i3p04.png", "s40n3p04.png", "tbbn0g04.png",
+	"tbbn2c16.png", "tbbn3p08.png", "tbgn2c16.png", "tbgn3p08.png", "tbrn2c08.png", "tbwn0g16.png",
+	"tbwn3p08.png", "tbyn3p08.png", "tm3n3p02.png", "tp0n0g08.png", "tp0n2c08.png", "tp0n3p08.png",
+	"tp1n3p08.png", "xc1n0g08.png", "xc9n2c08.png", "xcrn0g04.png", "xcsn0g01.png", "xd0n2c08.png",
+	"xd3n2c08.png", "xd9n2c08.png", "xdtn0g01.png", "xhdn0g08.png", "xlfn0g04.png", "xs1n0g01.png",
+	"xs2n0g01.png", "xs4n0g01.png", "xs7n0g01.png", "z00n2c08.png", "z03n2c08.png", "z06n2c08.png",
+	"z09n2c08.png",
+	"PngSuite.png", "logo-slim.png",
+]
+
+def try_download_file(url, out_file):
+	try:
+		with urllib.request.urlopen(url) as response, open(out_file, 'wb') as of:
+			shutil.copyfileobj(response, of)
+			print("... ", out_file)
+	except urllib.error.HTTPError:
+	 	print("Could not download", url)
+	 	return 1	
+
+def try_download_and_unpack_zip(suite):
+	url      = ASSETS_BASE_URL.format(suite, "{}.zip".format(suite))
+	out_file = DOWNLOAD_BASE_PATH.format(suite) + "/{}.zip".format(suite)
+
+	print("\tDownloading {} to {}.".format(url, out_file))
+
+	if try_download_file(url, out_file) is not None:
+		print("Could not download ZIP file")
+		return 1
+
+	# Try opening the ZIP file and extracting the test images
+	try:
+		with zipfile.ZipFile(out_file) as z:
+			for file in z.filelist:
+				filename = file.filename
+				assert(filename in PNG_IMAGES)
+				extract_path = DOWNLOAD_BASE_PATH.format(suite)
+
+				print("\t\tExtracting: {}".format(filename))
+				z.extract(file, extract_path)
+	except:
+		print("Could not extract ZIP file")
+		return 2
+
+
+def main():
+	print("Downloading PNG assets")
+
+	# Make PNG assets path
+	try:
+		path = DOWNLOAD_BASE_PATH.format("PNG")
+		os.makedirs(path)
+	except FileExistsError:
+		pass
+
+	# Try downloading and unpacking the PNG assets
+	r = try_download_and_unpack_zip("PNG")
+	if r is not None:
+		return r
+
+	# We could fall back on downloading the PNG files individually, but it's slow
+
+	print("Done downloading PNG assets")
+	return 0
+
+if __name__ == '__main__':
+	sys.exit(main())