FFTs are _________ techniques used to encode digital video and audio information and helps analyse the signal in ____________domain.
Compression, frequency
The Fast Fourier Transform (FFT) is an efficient algorithm, \(O(n \log n)\), for computing the discrete Fourier transform, which converts a sampled signal from the time domain into its frequency components.
In multimedia coding, transforming audio or video into the frequency domain separates important low-frequency content from high-frequency detail that the eye or ear barely notices. Those components can be quantised coarsely or discarded, which is the basis of transform-based compression (MP3 audio, the related DCT in JPEG and MPEG video).
So FFTs are used as compression techniques and they analyse the signal in the frequency domain.
FFT is not an encryption method: it is a reversible, publicly known transform with no key and gives no secrecy. And the signal is already in the time domain before the transform; the point of the FFT is to move it into the frequency domain.
Compression, frequency option is correct.
Similar Questions
Which of the following categories of languages do not refer to animation languages ?
Which of the following steps is/are not required for analog to digital conversion ?
(a) Sensing (b) Conversion (c) Amplification
(d) Conditioning (e) Quantization
Codes :
Which of the following is not a lossy compression technique ?
The process of dividing an analog signal into a string of discrete outputs, each of constant amplitude, is called :
From the given data below :
a b b a a b b a a b
which one of the following is not a word in the dictionary created by LZ-coding (the initial words are a, b) ?
Important Questions from Multimedia - Teaching
Which of the following categories of languages do not refer to animation languages ?
______ is used to reduce the size of multimedia files
- AIFF (.aif, .aiff, .aifc) file format is mainly used for _________.
Which of the following steps is/are not required for analog to digital conversion ?
(a) Sensing (b) Conversion (c) Amplification
(d) Conditioning (e) Quantization
Codes :
Which of the following is not a lossy compression technique ?
