Sound and video

Questions 1 to 5 of 8

1. 1. A recording is made at 44100 Hz. What is the highest frequency it can keep?

   44100 Hz22050 Hz20000 Hz88200 Hz
2. 2. A recorder samples at 8000 Hz. Is a 6000 Hz tone kept without aliasing?

   True, because 6000 is less than 8000, so the rate is high enough to hold itFalse, because the highest frequency kept is half the rate, which is 4000 Hz, so the 6000 Hz tone comes back as a false, lower sound
3. 3. A WAV sample is stored with 16 bits. How many different levels can one sample take?

   1625665,53616,777,216
4. 4. Match each term from the lesson to what it means.

   Choose the matching item for each row.

   sample rateChoose…bits used to store each sampleone stream of sound, such as the left or the righta sound above half the sample rate comes back as a false, lower tonesamples taken per second, measured in hertzbit depthChoose…bits used to store each sampleone stream of sound, such as the left or the righta sound above half the sample rate comes back as a false, lower tonesamples taken per second, measured in hertzchannelChoose…bits used to store each sampleone stream of sound, such as the left or the righta sound above half the sample rate comes back as a false, lower tonesamples taken per second, measured in hertzaliasingChoose…bits used to store each sampleone stream of sound, such as the left or the righta sound above half the sample rate comes back as a false, lower tonesamples taken per second, measured in hertz
5. 5. A raw video is 320 by 240 pixels at 10 fps. If its frame rate is doubled to 20 fps, does the raw file size double?

   True, because each second holds twice as many frames of the same size, so the total doublesFalse, because a higher frame rate only makes the motion smoother and does not change the file size