@param out buffer for encoded data
@param out_size size in bytes of the out buffer (including the
null terminator), must be at least AV_BASE64_SIZE(in_size)
@param in input buffer containing the data to encode
@param in_size size in bytes of the in buffer
@return out or NULL in case of error
Encode data to base64 and null-terminate.
@param out buffer for encoded data @param out_size size in bytes of the out buffer (including the null terminator), must be at least AV_BASE64_SIZE(in_size) @param in input buffer containing the data to encode @param in_size size in bytes of the in buffer @return out or NULL in case of error