No, that's not the case. Decompilers are not the same as Disassemblers.
As "Assemnly Language" is just another representation of machine code instructions of a given Processor, a Disassembler just makes machine code more readable.
A Decompiler tries to translate machine code back to a high level programming language wich is not bound to a given Processor. The result of even the most advanced Decompiler most likely won't be exactly the same as the source code.

 

Last edited: Sep 1, 2019

The decompiler translates in a high level code the disassembled code. Not the machine code itself. But we can say that assembler is a readable machine code. Translating the assembly to the machine code and vice versa is usually trivial.

Why have you called disassembler "decompiler"? In the picture you've posted I see DISASSEMBLER. It's an assembly. The program that outputs the assembly only is a disassembler