I'm dealing with some dictionary files and find the IPA of the words are represented with ACSII characters. For example, the IPA of "boring" is /ˈbɔrɪŋ/ while in the dictionary file it's recorded as /5bC:rIN/. I referred to some ASCII-IPAs like Kirshenbaum and X-SAMPA, but they are not what I'm looking for. Do you have any idea what the representation system is? Thank you.
PS: more representation pairs:
fiesta->[fɪ'estə]->/fi5estE/
periphrasis->[pə'rɪfrəsɪs]->/pE5rIfrEsIs/
filmstrip->[ˈfɪlmˌstrɪp]->/5fIlm7strIp/
placement->[ˈpleɪsmənt]->/5pleIsmEnt/