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 ...

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.

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).

sound waves cause air particles to vibrate back ... due to particles being spread further apart. In the diagram, the compression moved from left to right and energy is transferred from left ...

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 ...