If the width and height attributes are not set, the browser shows a small placeholder element resized to the dimensions of the video when the metadata becomes available.
If you do set the width and height attributes, the browser preserves the video's aspect ratio.
The following code shows the usage of the width and height attributes.
<!DOCTYPE HTML> <html> <head> <title>Example</title> <style> video { /*from w w w . ja v a2 s .co m*/ background-color: lightgrey; border: medium double black; } </style> </head> <body> <video src="http://java2s.com/style/demo/your.webm" controls preload="auto" width="600" height="240"> Video cannot be displayed </video> </body> </html>