How to edit the size of image while rotating?

Question

I have a gear image rotating using keyframe spin of CSS. but I want to resize the width of the image less than the height like in the image (see gear image below).

Demo gear rotating

.gear {
  position: absolute;
  top: 10%;
  left: 10%;
  width: 120px;
  height: 120px;
  -webkit-animation: spin 4s linear infinite;
  -moz-animation: spin 4s linear infinite;
  animation: spin 4s linear infinite;
}

@-moz-keyframes spin {
  100% {
    -moz-transform: rotate(360deg);
  }
}

@-webkit-keyframes spin {
  100% {
    -webkit-transform: rotate(360deg);
  }
}

@keyframes spin {
  100% {
    -webkit-transform: rotate(360deg);
    transform: rotate(360deg);
  }
}

<img class="gear" src="https://i.imgur.com/v1eydp4.png">

Answer 1

You can make use of the ScaleX transform value at various keyframe steps. It resizes at the last step to show you the difference in the size of it.

.gear {
  position: absolute;
  top: 10%;
  left: 10%;
  width: 120px;
  height: 120px;
  -webkit-animation: spin 4s linear infinite;
  -moz-animation: spin 4s linear infinite;
  animation: spin 4s linear infinite;
}

@-moz-keyframes spin {
  100% {
    -moz-transform: rotate(360deg);
  }
}

@-webkit-keyframes spin {
  100% {
    -webkit-transform: rotate(360deg);
  }
}

@keyframes spin {
  0% {
    transform: scaleX(0.5) rotate(360deg);
  }
  50% {
    transform: scaleX(0.5) rotate(0deg);
  }
  100% {
    -webkit-transform: rotate(360deg);
    transform: rotate(360deg);
  }
}

<img class="gear" src="https://i.imgur.com/v1eydp4.png">