Video encoding for DVDs and Blu-ray Discs

Making a DVD or Blu-ray Disc involves encoding your video into the MPEG‑2 format or the H.264 format (Blu-ray only). Compression reduces your video and audio files to take up less storage space. For example, a 60‑minute video in Adobe Premiere Elements takes up approximately 13 GB. However, a single‑layer DVD holds only 4.7 GB. (Dual‑layer DVDs hold 8.5 GB.) To maintain maximum quality, Adobe Premiere Elements compresses the movie only as much as necessary to fit it on the disc. The shorter your movie, the less compression required, and the higher the quality of the video on the disc.

Note: The Blu-ray presets are suitable for exporting AVCHD-quality files.[Italics in original]

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Note: The Blu-ray format H.264 is computationally intensive and, hence, takes a long time to encode. However, the compression is high and allows more video data per MB. MPEG-2 is not as computationally intensive, so it is faster, but the amount of video information per MB is less.