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How to compress WAV files?
Learned Video Compression WaveOne, Inc. November 2018 [Media coverage: WSJ, MIT Technology Review, etc.] Video compression is a critically important problem: video content consumes more than 75% of all internet traffic, and video consumption on mobile doubles every 18 months. Improvements to compression lead to higher quality content, less ...
What is video compression and how does it work?
A compression is the part of the wave (or Slinky) that is pressed together -- this is like the crest or peak of the wave. A rarefaction is the part of the wave (or Slinky) that is the most spread ...
Why is a compression wave different from a transverse wave?
20/12/2019 · Video: Compression wave demonstration View. Elaboration “Good Vibrations” Students will be asked to plan and conduct an investigation to prove that vibrating materials can produce sound and transmit energy using the CER model (claim, evidence, reasoning) (credit Edutopia). Begin by showing students this video. Tuning Fork Resonance + Ping Pong Ball. …
What is wave on video?
19/01/2022 · A compressional wave moves through a medium in the form of a longitudinal wave compression, and this is the source of the name for this type of wave. Parts of a Compressional Wave There are ...
What is compression in wave?
Compression. A compression is a region in a longitudinal wave where the particles are closest together. Rarefaction. A rarefaction is a region in a longitudinal wave where the particles are furthest apart.
What does a compression wave sound like?
0:041:00AudioPedia 101: Sound Waves Hearing - 2. Compression RarefactionYouTubeStart of suggested clipEnd of suggested clipIt's important to remember that the use of the term compression to describe high pressure variationsMoreIt's important to remember that the use of the term compression to describe high pressure variations in an acoustic sound wave has nothing to do with audio compression.
What is an example of a compression wave?
A compressional wave is made up of compressions and rarefactions that flow through the medium of the wave. A wavelength is the distance from one compression to another compression, or rarefaction to another rarefaction. Some examples of compressional waves include sound and P-waves, which are from earthquakes.
What's the difference between a transverse and compression wave?
We call traveling compression waves in liquids “longitudinal waves,” in contrast to “transverse waves” typified by a vibrating string. The direction that the material moves, relative to the direction of wave propagation, makes the difference.
Why is a sound wave also called a compression wave?
Mechanical longitudinal waves are also called compressional or compression waves, because they produce compression and rarefaction when traveling through a medium, and pressure waves, because they produce increases and decreases in pressure.
What type of wave is a compressional wave?
longitudinal wavesCompressional waves are also known as a longitudinal waves because of the way in which they travel through a medium. Compressions and rarefactions occur in the direction of travel, which is often visualized as the snapping of a slinky (see figure below).
What does compression mean in physics?
compression, decrease in volume of any object or substance resulting from applied stress. Compression may be undergone by solids, liquids, and gases and by living systems.
What is lossy compression?
Lossy video compression. Lossy compression means that a compressed file will contain less data than the original one. It’s the most efficient way to compress your video files for a smaller size. The downside: it can cause image quality loss.
How to compress video in QuickTime?
Here’s how you can compress your video in Quicktime: Open a video file you want to compress. Go to File > Export As > Option you like.
What is FFMPEG software?
Many of online multimedia projects, including YouTube and Wave.video, use FFmpeg software as one of the most powerful collections of libraries, codecs, formats, and programs for handling video, audio, and other multimedia files and streams.
Can you send a video via messenger?
if you want to send a video via a messenger. the idea of the video is more important than the quality. For other purposes it’s always a good idea to try different parameters, compare the quality and the file size to choose the best one for your needs.
How to compress video frames?
The key idea behind video compression is that consecutive frames in video are similar, and so it is advantageous to compress the difference each frame has with the previous one. This is done with two steps: 1 Motion compensation: many differences between consecutive frames are due to objects moving (or the camera panning). So, it is useful, for each pixel, to encode its motion vector: that is, where its relative location was in the previous frame. Given these motion vectors, we don’t need to encode the color of each pixel — we can simply copy it from the right location in the previous frame, obtaining what is known as the motion-compensated frame. 2 Residual compression: the difference between the motion-compensated frame and the original, called the residual, is often compressed using plain image compression techniques.
Why is motion compensation important?
So, it is useful, for each pixel, to encode its motion vector: that is , where its relative location was in the previous frame.
What is video compression?
Video compression in a nutshell. The key idea behind video compression is that consecutive frames in video are similar , and so it is advantageous to compress the difference each frame has with the previous one. This is done with two steps: Motion compensation: many differences between consecutive frames are due to objects moving ...
How efficient are codecs in predicting the next frame?
Traditional codecs are very efficient in predicting the next frame when there is a simple constant movement, such as a car passing by. However, there are many common spatio-temporal patterns that are not easy to describe with simple movement of pixels, such as an animal turning its head or a person walking.
What is the purpose of propagation of a learned state?
Propagation of a learned state. Traditional codecs use the previous frame and motion vectors as a “prior knowledge” to help encode the next frame. For example, since motion vectors don’t change too much from frame to frame, it is common to encode their difference.
How are areas of uniform motion represented?
Areas of uniform motion are represented by large blocks, whereas complex motion is represented by subdividing into smaller blocks , as shown on the left side below. While this representation compresses well, it cannot capture complex and fine motion effectively.
What is the video standard for phones?
Today every phone and many edge devices have a hardware chip implementing a video standard, such as H.264. Since the video compression algorithms are hard-coded into the chip, it is critical that the set of algorithms be commonly accepted by the community into a video coding standard.
Why are waves important?
The Importance of Waves. Waves carry energy, and in the case of earthquake waves, they carry huge amounts of energy. The first thing you feel when an earthquake hits is a longitudinal wave, and every sound you hear is a longitudinal wave. Waves are everywhere in nature and understanding them is an important part of explaining the world as a whole. ...
What is a slinky wave?
Longitudinal waves, also known as compression waves when describing waves in mechanical terms, are waves where the vibration is parallel to the direction the wave is moving. That might be hard to picture, which is why we need some help from a Slinky. It looks something like this:
Which earthquake wave causes the least damage?
Although the P-wave is the fastest earthquake wave, it causes the least damage precisely because it is a longitudinal wave. If the ground is shook up and down or side to side, like a longitudinal wave, there tends to be less damage than if the ground is waving around like a transverse wave.
What is longitudinal wave?
A longitudinal wave is what you get if you push a Slinky along its length, sending a pulse down it. The other type of wave is called a transverse wave. A transverse wave looks something like this. A transverse wave is a wave where the vibration is at right angles to the direction the wave is moving.
What is the difference between compression and rarefaction?
A compression is the part of the wave (or Slinky) that is pressed together -- this is like the crest or peak of the wave. A rarefaction is the part of the wave (or Slinky) that is the most spread apart -- this is like the trough of the wave. You can see how these compressions and rarefactions can be considered as crests ...
What is the wavelength of a wave?
A wavelength is the distance from two similar parts of a wave— from a peak to the next peak or from a trough to the next trough. It is the length of one full wave, one full oscillation. Wherever you measure it, the number should come out the same.
What is the first wave you feel when an earthquake hits?
The first wave you feel when an earthquake hits is a longitudinal wave -- this is called the primary wave, or P-wave. Although the P-wave is the fastest earthquake wave, it causes the least damage precisely because it is ...
Compression Waves
After the completion of this module students will understand that sound travels in compression waves and must have a medium to travel. Sound also travels in liquids and gases. Students will also understand that sound waves are created by vibrations and capable of transmitting energy.
Introduction
After the completion of this module students will understand that sound travels in compression waves and must have a medium to travel. Sound also travels in liquids and gases. Students will also understand that sound waves are created by vibrations and capable of transmitting energy.
Engagement
While watching the video students should be writing down what they’re noticing and what they’re wondering. Students can use paper & pencil or a digital platform such as Padlet. If paper and pencil is used, the teacher should record their responses on chart paper.
Explanation
1. Allow time for students to share their experiences with each set of materials.
Elaboration
Students will be asked to plan and conduct an investigation to prove that vibrating materials can produce sound and transmit energy using the CER model (claim, evidence, reasoning) (credit Edutopia).
Evaluation
Once students have completed their investigation and have filled out the claim and evidence section of their recording document, the reasoning section should be completed on their own and used to determine their understanding of how sound is created and able to transfer energy.
Additional Resources
For more information about Virginia Commonwealth University's School of Education STEM initiatives, visit the Center for Innovation in STEM Education (CISTEME).