compressing from dvd to dvdr what does it leave out?

[cs_exile]

You know when your copying a dvd, and the size is way to big to fit on ur dvdr and it says compressing and stuff, what exactly do u loose out on in the compression? does it lower the quality of the video? i cant honestly tell the difference however the filesizes are much smaller

[garryheather]

It depends how you do it - most people will strip out any extras and soundtracks they will not use in order to leave more space available for the main feature.

If it still doesn't fit, you either need to re-encode at a slower bitrate or transcode, which basically takes a hatchet to the video and takes away the "subtleties" that it doesn't think you will see in order to make the video smaller. Transcoding will generally leave the audio as is, but some people re-encode and convert say the 5.1 soundtrack into stereo and whack that along side as an MPEG audio track instead. Re-encoding is a time consuming process but will generally produce better results, although saying that I sometimes use DVD2ONE and that looks pretty good to my eyes for movie only titles.