Q&A for practitioners of the art and science of signal, image and video processing

178 "River" detection in text 2011-10-05T18:03:44.260

134 Why is the Fourier transform so important? 2011-08-19T04:40:06.970

122 What does frequency domain denote in case of images? 2012-03-06T04:16:59.280

95 What is the physical significance of negative frequencies? 2011-10-15T19:41:15.793

94 Why is it a bad idea to filter by zeroing out FFT bins? 2012-12-09T05:21:02.790

86 Why should I zero-pad a signal before taking the Fourier transform? 2011-11-30T20:54:11.180

84 What is the difference between a Fourier transform and a cosine transform? 2011-08-16T22:08:10.157

78 What is meant by a system's "impulse response" and "frequency response?" 2011-10-29T15:43:34.497

73 What are some free alternatives to SIFT/ SURF that can be used in commercial applications? 2012-01-31T13:40:26.297

69 Why do we use the HSV colour space so often in vision and image processing? 2012-06-22T13:41:40.963

65 How do I implement cross-correlation to prove two audio files are similar? 2010-10-29T07:04:47.807

62 If humans can only hear up to 20 kHz frequency sound, why is music audio sampled at 44.1 kHz? 2017-03-05T03:55:45.867

62 Why is TV static noise always black and white? 2018-01-15T02:25:37.297

61 Is deep learning killing image processing/computer vision? 2015-10-27T17:33:03.827

59 Why so many methods of computing PSD? 2012-04-18T10:09:20.330

57 What Is the Relationship Between a Kalman Filter and Polynomial Regression? 2012-05-13T15:46:07.340

57 What is the physical meaning of the convolution of two signals? 2012-10-20T18:52:01.683

56 What are some good signal and image processing blogs worth following? 2011-10-21T15:36:31.460

56 What is the distinction between ergodic and stationary? 2012-01-17T18:10:08.833

56 Algorithm(s) to mix audio signals without clipping 2012-10-07T09:01:48.737

54 Analogous Library to OpenCV for Audio Processing / Analysis 2011-12-07T17:33:24.150

52 What is the difference between convolution and cross-correlation? 2012-06-19T21:07:32.373

51 Best way of segmenting veins in leaves? 2012-03-14T14:02:43.800

49 What is the sparse Fourier transform? 2012-05-08T10:08:32.480

48 What is the difference between phase delay and group delay? 2011-09-12T16:14:22.720

47 Point Pattern Recognition 2011-10-27T07:41:43.300

47 What is the least JPG-compressible pattern? (camera shooting piece of cloth, scale/angle/lighting may vary) 2012-04-11T10:40:48.833

46 What algorithm does Google use for its "Search By Image" site? 2012-11-14T21:35:53.983

46 Meaning of Hilbert Transform 2015-09-15T14:33:06.950

45 What Resources Are Recommended for an Introduction to Signal Processing (DSP)? 2011-10-15T04:50:26.053

44 Simplest way of detecting where audio envelopes start and stop 2012-02-21T12:58:24.203

42 How to flatten the image of a label on a food jar? 2012-05-16T23:44:19.533

42 Why is the FFT "mirrored"? 2012-10-28T16:37:15.483

41 What Properties Make Certain Wavelets "Better" Than Others In Image Compression? 2011-09-27T19:06:52.943

39 What are the most common algorithms for adaptive thresholding? 2012-05-18T14:47:54.343

36 What's the difference between the Hough and Radon transforms? 2011-10-21T14:49:53.113

36 Does the autocorrelation function completely describe a stochastic process? 2011-10-24T17:49:11.250

36 The difference between convolution and cross-correlation from a signal-analysis point of view 2015-12-02T13:45:37.383

35 Determining the mean and standard deviation in real time 2011-12-03T05:11:29.650

35 Is there an algorithm for finding a frequency without DFT or FFT? 2012-02-02T04:00:35.523

34 What are good ways to detect signal clipping in a recording? 2011-08-18T19:37:44.083

34 What is the most lucid, intuitive explanation for the various FTs - CFT, DFT, DTFT and the Fourier Series? 2011-11-14T17:22:07.760

34 What is the true meaning of a minimum phase system? 2012-05-02T02:21:47.340

34 Finding squares in Image 2012-10-04T09:16:02.743

34 Understanding the Matched Filter 2013-05-12T02:52:53.490

33 What factors should I consider in choosing an edge detection algorithm? 2011-08-19T13:19:25.280

33 What Are the Best Algorithms for Document Image Thresholding (Example Inside)? 2012-04-04T08:19:28.063

32 Hilbert transform to compute signal envelope? 2011-10-14T19:07:44.707

32 Why are Gaussian filters used as low pass filters in image processing? 2012-07-31T19:22:02.817

32 What is the advantage of MATLAB's filtfilt 2013-06-05T09:36:47.667