Questions tagged [motion-estimation]
11 questions
17
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3 answers
How do the motion vectors work in predictive coding for MPEG?
In MPEG, there is a process where an image is broken up into macroblocks and a motion vector is computed for each of those macro blocks. You then transmit these vectors, along with the prediction errors, to reconstruct the next image in the video…
Wallet
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4
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2 answers
Does Gamma Correction Interfere with Sub Pixel Motion Estimation?
Advanced Video Coding (AVC) and High Efficiency Video Coding (HEVC) work on gamma corrected, non linear, colors.
When interpolating the value at subpixels, a multi tap algorithm processes the gamma corrected values of the original pixels directly,…
Bruno Martinez
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3
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What motion estimation techniques that could estimate the motion of every pixel?
I'm trying to estimate a motion from a video, however based on my finding, those methods usually meant for large motion and sparse in nature.
Optical flow: Sparse and fail to detect sub-pixel motion
Phase-based: Only applicable to global shutter…
Gregor Isack
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3
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4 answers
Create images with sub-pixel shift
I want to test some motion estimation algorithms which compute motion with sub-pixel accuracy. I can create images shifted by the order of pixel (e.g. [2,2]) using MATLAB or OpenCV but I am not clear on how can I shift images with sub-pixel (e.g.…
Saikat Das
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1
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2 answers
Does a gyroscope get impacted by gravity?
When processing IMU data, does the gyroscope get impacted by gravity? Linear accelerometers need to have gravity compensation but nothing is said of IMU.
FourierFlux
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Producing images with subpixel shift in region of interest
Let's say for a zebra image, and at certain pixel location, I would like to makes it "vibrate/warp" to and fro in horizontal direction at a certain frequencies in a sequence of images of time t, with subpixel shift. The circled area is the most…
Gregor Isack
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Obtaining Correct (Least Squares Sense) Affine Transform Parameters Between Two Images
I have two images that I want to compute the affine motion model parameters. The model that I use is $$x' = a_1x+a_2y+a_3$$ $$y' = a_4x+a_5y+a_6$$
To calculate those 6 parameters, I picked 6 points (overdetermined system) between two images, and…
Canberk
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Extraction of reference frame information and motion vector from H.264 video files
I'm looking for tools/code for the extraction of motion vectors and information regarding the reference frame used by each macroblock with which its motion vector is calculated.
I have tried 2 tools based on FFmpeg :
MV-Tractus
mv-extractor
Both…
0
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0 answers
How do I derive complicated robotic motion models easily?
I have a filter that tracks a robot. I want it to use a 2D coordinated turn polar velocity motion model (from page 15 here):
But I want to expand on this motion model: I want an additional velocity state that is orthogonal to the heading, and I…
blåblomma
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Possible ways to determine the direction of moving object?
I'm trying to determine the moving direction of an object in x-axis only. Figure below shows part of my effort.
However, I got stuck. As you can see from the middle image, the green represent the dot moved to right (positive x), the black represent…
Gregor Isack
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Classify type of motion using decision trees and features
Consider a decision tree for separating between the following activities: Sitting, Driving, Running, Walking. Assume that you are given the following features: Dominant frequency (F1), meanX, meanY, and meanZ (mean acceleration along the three…
Shivangi Singh
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