Imports github.com/golang/freetype golang.org/x/image/draw golang.org/x/image/font Standard library imports bytes crypto/md5 crypto/rand encoding/base64 encoding/hex encoding/json errors fmt go-captcha/captcha/assets image image/color image/jpeg image/png io/ioutil math math/big math/rand os path/filepath regexp strconv strings sync sync/atomic time unicode unicode/utf8