Changing the size of an embedded video

Testing the best embed code for a video if I want to change the size.

Directly from You Tube:
<iframe width="560" height="315" src="https://www.youtube.com/embed/rzeW741NLPY" frameborder="0" allowfullscreen></iframe>

I have  changed code to make the video smaller. The aspect ratio has been changed. I now get black lines on the top and bottom of the video.
<iframe width="320" height="266" src="https://www.youtube.com/embed/rzeW741NLPY" frameborder="0" allowfullscreen></iframe>

<iframe width="320" height="180" src="https://www.youtube.com/embed/rzeW741NLPY" frameborder="0" allowfullscreen></iframe>

The embed code has been altered but the aspect ratio kept the same by using an aspect ratio calculator.

Thanks to Anushika for the video.
https://phsanushikap.blogspot.co.nz/2017/04/tagimoucia-video-video-is-made-in.html?showComment=1493178347953#c6484729830277199045

Test Photo Peach

Teacher Learning on PhotoPeach

All About Me

We are learning how to do a blog post.

Sped Up Sea Creature Animation

We have been learning about using google drawing and then creating an animation using google slides. My next step is to add audio by using screencastify.

Once the slides are published to the web I copy the embed code as normal. When I paste it into the HTML on my blog I change the timing to speed up the slides when they play.

Original speed:

Change the speed to 300ms: