this time is difficult for me to explain problem i was facing. i realize that R/S signature in DER signature is not match to the 1 in bitcoin signed message? Ok below is my say signed message.
-----BEGIN BITCOIN SIGNED MESSAGE-----
-----END BITCOIN SIGNED MESSAGE-----
my working way is $decoded_content = bin2hex(base64_decode(IPnTEOU713+XclrBrUEfTLeP0A7QIR4lObzQjBjyxGQExPwkalrQK1JOggIWk4xrfWIjHEC0RKGv3vtguDfto0o=))
then i manage to get R/S signature from $decoded_content. after that, i use R/S signature to generate DER signature. I realized that this DER signature is fail in signature verification.
shortly to say,
my program check valid signature using function in https://github.com/tuaris/CryptoCurrencyPHP/blob/master/Wallet.class.php#L225
if another party send me DER signature, how do i convert it into base64_encoded string? so end up i am able to use function i mention just now.
I try alot of methods but no luck, are R/S signature in both signed message and DER signature means to same?