What free software that can improve the quality of a media file or dvd?

Question

That improves quality, resolution and sharpness of the picture.

Answer 1

I'm sorry, but once a photo has been converted to a lower quality it is impossible to upgrade to a better quality. You see, when you take a raw photo in its native resolution, etc, and change it to a particular format, it is compressed. How much quality is lost depends on the format converted to. If somebody takes a photo and uses the "compress for smaller size" to send via email, or upload to a blog, etc, information is removed. How small the photo is reduced determines how much is removed. Some photo formats compress so little it is very difficult to tell the original from the new, while other formats remove so much quality is greatly reduced.

This is the same for video. In fact, it can be worse for video. When a video is formatted to be uploaded to YouTube a great deal is lost in the compression. Music files also are the same. Conversion from one format to another lessens the quality. For example, an MP3 is a conversion that keeps fidelity in many ways, making it difficult for the ear to tell quality has been reduced, but if you listen to the original and then the MP3 version you will be able to tell if you are not tone deaf. The lower the conversion the more loss in quality.

When these items are removed it is impossible to get them back. Please do not confuse video Codecs with conversion from format to format. A Codec compresses the video and music, but it doesn't rip anything out. It only compresses enough to squish the data there into smaller pieces, rather like squishing a piece of bread. The bread may be a ball, but all of the bread is there. This isn't true when changing format.

When you have a original multimedia file you wish to convert for another purpose be sure to use the Copy As command to keep an original. Work with the copy when altering formats. That way you never need worry about losing quality for other projects or purposes.

If I misunderstood your question I apologize. Good luck and have a nice day.