You need Hikvision FIRMWARE TOOLS https://www.ipcamtalk.com/showthread.php/2733-Hikvision-FIRMWARE-TOOLS-change-language-extract-files-and-create-own-firmware
If you use this version, command in windows command promt (CMD) will be "hiktools05R1 lang digicap.dav 1" or "c:\folder\hiktools05R1...