DVD vs Blu-ray

This post is about the differences of DVD and Blu-ray. I am going to look at their meaning and qualities.

DVD - Digital Versatile Disc or Digital Video Disc

DVD was invented in 1995 and it holds more data than regular CD-s, being able to store full movies at higher qualities. DVD is starting to lose its job to Blu-ray, because of the need of bigger information storage capacaty.

• Capacaties vary from 4.7 to 17.08 GB, can be either single or dual-layered.
• Requires a DVD reader in order to read the disk.
• Allows to store any kind of data.
• Relatively small cost of drives and discs.

Blu-ray

The name comes from the blue laser that reads the disc, the laser works at short wavelength and the data on the disc can be stored at a greater density. Blu-ray came after DVD, in fact, it was actually the successor to DVD. The first prototype was relesed in Japan 2003, but it continued in 2006 when they released it officially. Blu-ray is still in development but it's growing fast and coming more popular every day, especially in the movie and gaming industry.

• Capacaties vary from 25 to 128 GB, can be either single or dual-layered.
• Requires a BluRay reader in order to read the disk.
• Allows to store any kind of data.
• High definition video and high quality audio.
• High cost of drives and discs.
• Supports newer audio/video codecs.

Movies on Blu-ray: 720p and 1080p explained

The number 720/1080 means that there are 720/1080 horizontal lines of vertical resolution, assuming a 16:9 ratio it means that the resolution is 1920x1080 pixels. The letter "p" behind it means "progressive scan", refering that the image is not interlaced ( frames are not displayed as separate frames, in this case lines ).

Movie image quality comparison

These comparison screenshots are taken from the movie "The Dark Knight Rises"

DVD

Blu-ray 720p

Blu-ray 1080p

A closer look at Bruce Wayne's head

Another example, taken from the same movie in a different scene

As you can see, the difference in image quality is noticeable. You may not think that it's much when zoomed in, but it sure makes a difference when watching a movie on bigger screens.