test.asm

  unsigned char* bitmap = img -> informacion;                    //Se solicita el apuntador a los componentes de la imagen.
  int word_size = CHAR_SIZE;                                     //Tamaño inicial de palabra
  int cant_char = 0;                                             //Cantidad de caracteres extraídos
  int bitmap_pos = 0;                                            //Índice del componente actual de la imagen
  int extracted_chunks = 0;                                      //Paquetes recuperados por componente
  int num_chunks = CHAR_SIZE / n;                                //Número de paquetes que se pueden extraer de acuerdo al tamaño n solicitado
  int offset = CHAR_SIZE % n;                                    //Sobrante sujeto al número de paquetes por n.

;Salvaguarda
push eax
push ebx
push ecx
push edx
push edi

mov esi, [bitmap] ; Char*
lea edi, msg
mov ebx, 0 ; Máscara de zeros → bl
;cl → Caracter actual
procesar_imagen:
    mov ecx, [l]
    cmp [cant_char], ecx
    jge fin_procesar
    mov [extracted_chunks], 0
    mov eax, [word_size]
    mov ecx, [n]
    mov edx, 0
    div ecx
    mov [num_chunks], eax
    mov [offset], edx
    extract_chunks:
       cmp [extracted_chunks], eax
       jle fin_extract
       mov edx, [bitmap_pos]
       mov cl, [esi + edx]
       mov edx, 0
       mov edx, 8
       sub edx, [n]
       shl cl, dl
       shr cl, dl
       or bl, cl
       inc [bitmap_pos]
       mov edx, [num_chunks]
       sub edx, 1
       cmp [extracted_chunks], edx
       je fin_extract
       mov edx, [n]
       shl bl, dl
       inc [extracted_chunks]
       jmp extract_chunks
    fin_extract:
       cmp [offset], 0
       je no_offset
       mov edx, [bitmap_pos]
       mov cl, [esi + edx]
       mov edx, 0
       mov edx, 8
       sub edx, [n]
       shl cl, dl
       shr cl, dl
       mov edx, [offset]
       shl bl, dl
       push ecx
       neg edx
       add edx, [n]
       shr cl, dl
       or bl, cl
       mov edx, [bitmap_pos]
       mov byte ptr[edi + edx], bl
       mov ebx, 0
       mov edx, 8
       add edx, [offset]
       sub edx, [n]
       mov [word_size], edx
       mov edx, 0
       mov eax, [word_size]
       push ecx
       mov ecx, [n]
       div ecx
       mov [offset], edx
       inc [bitmap_pos]
       pop ecx
       mov edx, 8
       sub edx, [offset]
       cmp edx, [n]
       jge cond_2
       or bl, cl
       jmp pre_proc
       cond_2:
         mov dl, cl
         shl dl, byte ptr [n]
         or bl, dl
       jmp pre_proc
    no_offset:
      mov edx, [cant_char]
      mov byte ptr [edi + edx], bl
      mov ebx, 0
      push ecx
      mov ecx, [n]
      mov edx, 0
      div ecx
      mov [offset], edx
      mov [word_size], 8
      pop ecx
    pre_proc:
       inc [cant_char]
       mov [extracted_chunks], 0  
       jmp procesar_imagen

fin_procesar:
    pop edi
    pop edx
    pop ecx
    pop ebx
    pop eax