这是什么编码解决思路

这是什么编码
dDw4NzEyMDk0MzQ7dDw7bDxpPDE%2BOz47bDx0PDtsPGk8Mj47aTw4Pjs%2BO2w8dDxwPHA8bDxUZXh0Oz47bDwyMDE0LTIwMTXnrKzkuIDlrabmnJ87Pj47Pjs7Pjt0PDtsPGk8MD47PjtsPHQ8O2w8aTwwPjtpPDE%2BO2k8Mj47PjtsPHQ8cDxwPGw8SG9yaXpvbnRhbEFsaWduO18hU0I7PjtsPFN5c3RlbS5XZWIuVUkuV2ViQ29udHJvbHMuSG9yaXpvbnRhbEFsaWduLCBTeXN0ZW0uV2ViLCBWZXJzaW9uPTEuMC41MDAwLjAsIEN1bHR1cmU9bmV1dHJhbCwgUHVibGljS2V5VG9rZW49YjAzZjVmN2YxMWQ1MGEzYTxSaWdodD47aTw2NTUzNj47Pj47Pjs7Pjt0PHA8cDxsPEhvcml6b250YWxBbGlnbjtfIVNCOz47bDw1MDxDZW50ZXI%2BO2k8NjU1MzY%2BOz4%2BOz47Oz47dDxwPHA8bDxIb3Jpem9udGFsQWxpZ247XyFTQjs%2BO2w8NTA8TGVmdD47aTw2NTUzNj47Pj47Pjs7Pjs%2BPjs%2BPjs%2BPjs%2BPjtsPDIxOzIyOzIzOzI0OzI1OzI2OzI3OzI4OzI5OzMwOzMxOzMyOzMzOzM0OzM1OzM2OzM3OzM4Oz4%2BzElOL0gk3AJyKWXnZbe4hXwMW3Y%3D  
------解决方案--------------------
echo base64_decode(urldecode($s));