I know this may require some javascript but how can I tell the input inside my form to reject images with size different than 64 x 64 without pressing the submit button.
<div class="form-group">
<label for="plat_img">Icono</label>
<input type="file"
accept="image/*"
class="form-control"
id="plat_img">
The verification should happen as soon as the image is selected and if rejected, notify the user via an alert.