关卡地址
解决方案：
思路：
这一关的提示比较干净，一切都需要从图片中提取分析。
把所有像素值提取到文本，以下为前4行前8列像素数据：
(0, 20, 0)(142, 180, 105)(0, 20, 0)(139, 177, 100)(0, 20, 0)(143, 180, 103)(0, 20, 0)(138, 175, 98)
(148, 186, 111)(0, 20, 0)(148, 186, 109)(0, 21, 0)(144, 181, 104)(0, 20, 0)(144, 181, 104)(0, 20, 0)
(0, 20, 0)(158, 195, 118)(0, 20, 0)(148, 185, 108)(0, 22, 0)(152, 189, 112)(0, 19, 0)(150, 184, 110)
(145, 182, 105)(0, 22, 0)(158, 195, 118)(0, 20, 0)(155, 189, 113)(0, 19, 0)(146, 180, 104)(0, 20, 0)
可以看出，绿色(0, x, 0)与彩色有规律的穿插着，绿色像素分布在偶数行偶数列和奇数行奇数列，彩色像素分布在偶数行奇数列和奇数行偶数列。
我们要做的就是把彩色像素替换为白色(255,255,255)，下一关地址就会浮现出来了。
代码：
import helper
path=".\\Data\\011"
helper.ensureDir(path)
# ================================
# 使用http认证，下载图片
import urllib.request
helper.installHTTPBasicAuthOpener("huge", "file")
cave="http://www.pythonchallenge.com/pc/return/cave.jpg"
(filename, headers)=urllib.request.urlretrieve(cave, path+"\\cave.jpg")
# ================================
# filename=path+"\\cave.jpg"
from PIL import Image
im=Image.open(filename)
px=im.load()
(w,h)=im.size
# ================================
# 输出像素文件
# outstr=[]
# for y in range(h):
# for x in range(w):
# outstr.append(str(px[x,y]))
# outstr.append('\n')
# fp=open(path+'\\cave.txt','w',encoding='utf-8')
# fp.write(''.join(outstr))
# fp.close()
# ================================
pixel=(255,255,255)
for y in range(h):
for x in range(w):
p=(x,y)
if y%2 == 0 and x%2 == 1:
px[p]=pixel
elif y%2 == 1 and x%2 == 0:
px[p]=pixel
# im.save(path+'\\cave.info.jpg','jpeg')
im.show()
im.close()PS src\static> python .\Code\Python\Challenge011.py$path=".\\Data\\011"
. .\Code\PowerShell\helper.ps1
New-Dir -Dir $path
$cave="http://www.pythonchallenge.com/pc/return/cave.jpg"
$filename=$path+"\\cave.jpg"
Get-FileWithAuth -Url $cave -Filename $filename -Username "huge" -Password "file"
[void][System.Reflection.Assembly]::LoadWithPartialName("System.Drawing")
$img=[System.Drawing.Image]::FromFile($filename)
$color=[System.Drawing.Color]::FromArgb(255,255,255)
for ($y = 0; $y -lt $img.Height; $y++) {
for ($x = 0; $x -lt $img.Width; $x++) {
if ($y % 2 -eq 0 -and $x % 2 -eq 1) {
$img.SetPixel($x, $y, $color)
} else {
if ($y % 2 -eq 1 -and $x % 2 -eq 0) {
$img.SetPixel($x, $y, $color)
}
}
}
}
Show-Image -Title "Challenge011" -Image $img
# $img.Save($path+"\\cave.info.jpg")
$img.Dispose()PS src\static> .\Code\PowerShell\Challenge011.ps1package main
import(
"image"
"image/color"
)
func (c *Challenge) Challenge011() {
path:=".\\Data\\011"
EnsureDir(path)
url:="http://www.pythonchallenge.com/pc/return/cave.jpg"
filename:=path+"\\cave.jpg"
DownloadWithBasicAuth(url, filename, "huge", "file")
im:=OpenImage(filename)
bounds := im.Bounds()
whitecolor:=color.White
rgba:=image.NewRGBA(bounds)
for y := bounds.Min.Y; y < bounds.Max.Y; y++ {
for x := bounds.Min.X; x < bounds.Max.X; x++ {
if y%2==0 && x%2==1 {
rgba.Set(x,y,whitecolor)
} else if y%2==1 && x%2==0 {
rgba.Set(x,y,whitecolor)
} else {
rgba.Set(x,y,im.At(x,y))
}
}
}
jpgfile := path+"\\cave.info.jpg"
SaveImage(jpgfile, rgba, "jpeg")
ShowImage(jpgfile)
}PS src\static> .\Code\Go\Challenge.exe -l 011