How to convert a data type file to blob in ionic

hi team, I bring you this query as the matter says.

  <ion-header>
  <ion-toolbar color="asid">
    <ion-buttons slot="start">
      <ion-back-button defaultHref="/listar-checklist"></ion-back-button>
    </ion-buttons>
    <ion-title>Nuevo Checklist</ion-title>
  </ion-toolbar>
</ion-header>

<ion-content>
  <div id="container">
    <form [formGroup]="checkForm" (ngSubmit)="submit()">


      <ion-card style="background-color: rgb(170, 196, 245)">
        <ion-card-header style="text-align: center">

            <!--SELECCION DE OPERARIO-->

            <ion-select placeholder="Seleccione Operario" #C (ionChange)="onSelectOperario($event.detail.value)">
              <ion-select-option
                *ngFor="let usuario of operarioArray"
                [value]="usuario">
                {{usuario.$$title}}
              </ion-select-option>
            </ion-select>

            <!--SELECCION DE vehiculo-->

            <ion-select placeholder="Seleccione Vehiculo" #C (ionChange)="onSelectVehiculo($event.detail.value)">
              <ion-select-option
                *ngFor="let dominio of vehiculoArray"
                [value]="dominio">
                {{dominio.$$title}}
              </ion-select-option>
            </ion-select>


          <!-- </ion-card-title> -->
        </ion-card-header>
      </ion-card>
      <ion-card>

        <ion-item>
          <ion-icon name="medkit" slot="start"></ion-icon>
          Identificacion: &nbsp;
          <ion-input type="text" formControlName="identificacion"></ion-input>
        </ion-item>

        <ion-item>
          <ion-icon name="medkit" slot="start"></ion-icon>
          Destino: &nbsp;
          <ion-input type="text" formControlName="destino"></ion-input>
        </ion-item>

        <ion-item>
          <ion-icon name="medkit" slot="start"></ion-icon>
          <ion-label>Fecha de Salida</ion-label>
          <ion-datetime
            value="03-06-2021"
            formControlName="fechaDeSalida"
            displayFormat="DD/MM/YYYY"
            pikerFormat="YYYY MM DD"
            placeholder="Seleccione Fecha"
            cancelText="Cancelar"
            doneText="OK"
          ></ion-datetime>
        </ion-item>


        <ion-item>
          <ion-icon name="medkit" slot="start"></ion-icon>
          <ion-label>Documentacion</ion-label>
          <ion-select interface="popover" formControlName="documentacion">
            <ion-select-option>Habilitado</ion-select-option>
            <ion-select-option>NoHabilitado</ion-select-option>
          </ion-select>
        </ion-item>


        <ion-item>
          <ion-icon name="medkit" slot="start"></ion-icon>
          <ion-label>Tablero</ion-label>
          <ion-select interface="popover" formControlName="tablero">
            <ion-select-option>Habilitado</ion-select-option>
            <ion-select-option>NoHabilitado</ion-select-option>
          </ion-select>
        </ion-item>


        <ion-item>
          <ion-icon name="medkit" slot="start"></ion-icon>
          <ion-label>Laterales</ion-label>
          <ion-select interface="popover" formControlName="laterales">
            <ion-select-option>Habilitado</ion-select-option>
            <ion-select-option>NoHabilitado</ion-select-option>
          </ion-select>
        </ion-item>


        <ion-item>
          <ion-icon name="medkit" slot="start"></ion-icon>
          <ion-label>Seccion Trasera</ion-label>
          <ion-select interface="popover" formControlName="seccionTrasera">
            <ion-select-option>Habilitado</ion-select-option>
            <ion-select-option>NoHabilitado</ion-select-option>
          </ion-select>
        </ion-item>


        <ion-item>
          <ion-icon name="medkit" slot="start"></ion-icon>
          <ion-label>Frente</ion-label>
          <ion-select interface="popover" formControlName="frente">
            <ion-select-option>Habilitado</ion-select-option>
            <ion-select-option>NoHabilitado</ion-select-option>
          </ion-select>
        </ion-item>

        <ion-item>
          <ion-icon name="medkit" slot="start"></ion-icon>
          Comentarios: &nbsp;
          <ion-input type="text" formControlName="comentarios"></ion-input>
        </ion-item>
        
        **<ion-item>
          <ion-icon name="medkit" slot="start"></ion-icon>
          Fotos: &nbsp;
          <ion-input type="file" formControlName="fotos"></ion-input>
        </ion-item>**

      </ion-card>

      <ion-button
        type="submit"
        style="background-color: rgb(170, 196, 245)"
      >
        Guardar
      </ion-button>
    </form>
  </div>
</ion-content>


This is the error that I am getting now when I try to upload a photo


 https://i.stack.imgur.com/IdrC9.jpg


I await answers
best regards