Imports github.com/alexflint/go-arg github.com/h2non/bimg github.com/labstack/echo/v4 github.com/labstack/echo/v4/middleware github.com/labstack/gommon/log github.com/ultimate-guitar/go-imagequant Standard library imports encoding/hex fmt image/png io io/ioutil log net/http net/url os strconv strings time