Lossy methods can provide high degrees of compression and result in smaller compressed files, but some number of the original pixels, sound waves or video frames are removed forever. Examples are ...

7xx voice formats are widely used "lossy" methods that analyze which pixels, video frames or sound waves can be removed forever without the average person noticing (see lossy compression).

For example, a question about ... and compression are the wrong way round. Compression is where the particles are more concentrated. Longitudinal waves change gradually and do not have bands.

It is also the time taken for one complete wave to pass by, for example the time from one compression to pass until the next. Displacement-distance graphs are diagrams that can be used to compare ...

For example, producing a long ... that are close to each other. Pulse compression uses a long transmission that varies in frequency. Reflected waves can be reconstituted to act more like a short ...