# Tagged Questions

Algorithms for processing video signals i.e. sequence of images either for enhancements, conversions or analysis of objects within it.

62 views

### Calculate sum of absolute difference per pixel

I am trying to implement a research paper just to verify my results. I have shared the code (written by me) and the description of the process given in the research paper. Unfortunately my results are ...
32 views

### Hardware advice for machine vision project

I am working in facial feature detection in video images. I was hoping to get some general advice about camera/lens technologies to determine if I can upgrade my camera/lens. Basically, the problem ...
18 views

### Projector image subtraction

Imagine you have a projector and camera pointed at a wall, with people walking in front of the wall (between projector and wall). Is there a standard way to robustly obtain silhouettes of the people ...
60 views

### How to get dct coefficients in libav

I want to implement an LSB-steganography algorithm for h264-encoded video. According to this paper, I need to modify the quantized coefficients in encoder, and translate video (via vlc-media player). ...
52 views

### Count the vehicles flow that pass over one bridge

I live in an apartment near a bridge. From my window I can see the cars traveling over the bridge as you can see below: Is there a relatively simple manner to count each car pass over the bridge? ...
87 views

### Identifying license plate number of a thief's car from a video

Motivation: I recently had my laptop stolen, with lots of pictures of my family, research work and other very important stuff. Of course the theft has been reported, but I think people here are more ...
11 views

### Calculate SSIM or PSNR of video file with lost packets

I am encoding my video using JM and with packetization mode RTP. I want to test effect of different videos under different packet loss ratios. But unfortunately only videos with 1% packet loss ratios ...
38 views

### How to specify 2-D coordinates of an object in matlab?

This is the scenario: I marked two axes (figure below) on a board and a camera(global vision system) sees the board. I want to make the vision system to recognize $X$ and $Y$ axes and specify ...
17 views

### Controlling the pursuit path of the human eye?

The human eye scans images by panning focus along a certain path. I've read that eye tracking studies have revealed that there is a feedback process involved in moving ocular focus along a path that ...
100 views

### Real-time depth estimation in MATLAB

I want to estimate depth from live video stream with two calibrated webcams in MATLAB but has no results. I have Webcam Support Package and Image Acquisition Toolbox but I don't know how to use live ...
19 views

### Depth estimation from live video stream [duplicate]

I have two calibrated cameras and webcam support package and image acquisition toolbox. in this post depth is estimated from two recorded videos but my application is real-time and I want to estimate ...
122 views

### Depth estimation from live video stream in matlab

I want to estimate depth from live video stream with two calibrated webcams in matlab but has no results. In this post depth is estimated with two recorded video files. how can I estimate depth in ...
74 views

### Extracting DCT coefficients from H.264/AVC bitstream

Is it possible to extract DCT coefficients from H.264/AVC bitstream without doing a full-decoding of the video? There are a lot of papers on compressed domain video processing which are based on the ...
25 views

### Is there a way to see video after applying packet loss

I have encoded a video stream using JM using RTP. Then i have applied rtp_loss on it but after that i am unable to decode video. Like in this example a video with different packet loss percentages are ...
67 views

### How to convert lut to 3d lut?

I have a lookup texture below which i got from some website(seems to be 8x8 2d LUT). I want to apply this LUT on a video. ￼ Final cut pro/adobe premiere supports 3d LUT but I dont know to recreate ...
177 views

### Simulate packet loss in internet video streaming

i have encoded H.264 video using ffmpeg . I want to apply packet loss model like Gilbert Eliot model to depict video transmission over unreliable network. Like in this thread TV noise is simulated. ...
82 views

### Which softwares can process 2D Lookup table?

I have a look up table like this... I would like to know which video and image editors can process 2D LUTs.
26 views

### Apply noise in H.264 Stream

I have Encoded H.264 bitstream using JM. I want to pass this stream to the common noisy channel or packet loss models. So that i can check effect of packet loss on perceptual video quality. My ...
182 views

### Detect ending of frame in H.264 video stream

I am using JM reference software for encoding and decoding of video. What I want to do is to add Redundant bits using RS codes to the encoded video so that if some bits get lost during transmission we ...
26 views

### Designing 2D DFT filter that works with cycle per degree

Here is my question regarding 2d dft. I know how to do 2d-dft and convolution and filtering. However, I still have a basic question. Maybe I have not understand the concept, and that's why I don't ...
35 views

### Comparing AR coefficients derived from different sampling rates

I'm interested in comparing the coefficients of AR processes computed from different dynamic texture videos. That is, $A_1$ and $A_2$ are the $d \times d$ coefficients for dynamic texture videos 1 and ...
135 views

### Live Video processing using hadoop?

How can I process a live video stream using hadoop? Case in point is Opencv, how it processes a live video frame by frame. Can it be done in hadoop? Else, can a mechanism be made in which opencv ...
30 views

### Accurate measurement of object's position on a bayer-filtered and grayscaled images

This is an experience-related question about cameras and image processing. I have a laboratory setup. Under some simplifications it looks like a red ball rolling on a white table (the real setup is ...
34 views

### Matching two video conversations

I have two video where two person having conversation. They begin recording different times. I want to match these two videos' frame numbers, i.e. By matching audio. How can I do that?
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### Difference between video mosaicing and video stitching

What is the difference between video mosaicing and video stitching ,is this both are similar or is there any methodology difference?
67 views

### How to increase the resolution of a video from a sequence of photos?

I have a video filmed in a relatively low quality and resolution and a sequence of photos of higher quality taken of the same scene at the rate of about one image every two seconds or so. Could those ...
105 views

### HEVC Deblocking filter algorithm

I'm doing research on block noise caused by video compression (especially in newer codecs) and I've read the IEEE article about the HEVC deblocking filter (here). However, when reading the algorithm ...
64 views

### Optical Flow Problems

I was wondering if any of you guys could help me with the next 3 problems. They're about estimating the lamda on the Optical Flow equation $E = E_s + λE_c$, for different situations that try to ...
115 views

### Image processing for eye movements

I have series of images extracted from a eye tracker video for both eyes. is there any image processing algorithm/method/technique available to find the following from those images: Horizontal eye ...
105 views

### Difference Between monocular video and stereo video?

What is the difference between monocular video and stereo video ,as i am studying about motion tracking i need to know the meaning of these two things.
183 views

### Why does cel-shading sometimes look similar to rotoscoping?

Why does cel-shading sometimes look similar to rotoscoping? Rotoscoping: A Scanner Darkly: Cel-shading: Wikipedia: Cel-shading, Teapot Example:
643 views

### Is it possible to have negative PSNR?

I have been working on image processing. I have an image and then add it a Gaussian noise with standard deviation=0.005. then using averaging filter to denoise it (I know it is not a good idea). then ...
47 views

### Noise modeling and reduction in Video when we have just noisy video

We would like to send a video (sequence of images), we have limit bandwidth. If there is a lot of noise, the required bandwidth (bitrate) is needed to send the video+noise becomes high that is not ...
25 views

### Find large distinctions in Video

Assume you have 77777 pictures that are mostly noise. They are about magnetic anisotropy. There is one picture among these pictures which has high contrast difference between two large areas (some ...
36 views

### Is it correct to call this Gaussian Mixture Model?

Some poeple claim their background subtraction algorithms use Gaussian Mixture Model, but when I read the code, I find they actually use only one component, and as a result EM algorithm (or its ...
64 views

### Equivalent of the Shepp-Logan phantom for video denoising

The Shepp-Logan phantom is a standard test image used in reconstruction algorithms as well as image denoising. Does an equivalent image sequence exist for testing video denoising algorithms? I know ...
77 views

### Video: Detecting a digital timer and when it ticks

Input: A video with a digital timer, possibly several hours long, such as this video. The timer might use any font or color, and might be located anywhere on the video, but it probably won't fill the ...
71 views

### How are video thumbnails chosen?

Of the thousands to millions of frames that a video might have, how is a particular representative frame chosen to be the thumbnail?
68 views

### Detecting characters in high contrast/oversaturated regions

I'm currently tagging insects with reflective tags and filming them in night-mode on my camera which has an infrared light. I have some markings on the tags which I need to catch on film. ...
228 views

### Map time difference between two similar videos

Question: Is there any software, source-code, or well documented and easily implementable research (I am not afraid for a little bit of Python) to do the following: Take two similar videos from ...
314 views

### .ptw Video conversion

On Video recording with IR camera, a file in .ptw is obtained. I want to analyze the file using standard software, like MATLAB. However, video processing in MATLAB requires the file to be converted to ...
34 views

### Detecting inset images/videos from a video

I want to detect multiple rectangles in a video, each of which features a different content, but running simultaneously. This is typically seen during debates on news channels. For example, in the ...
84 views

### Image and video processing in matlab

I have been working on Digital signal processing since Feb-2013. I have good command over it. Now I want to expand work in field of IMAGE and Video processing. Please suggest me best practical guide ...
31 views

### Please suggest me good algorithm for video segmentation based on changing background?

Iam having 1 min video.I need to cut the video into 5 segments depending on changing background.Please suggest me good algorithm which can be easily implemented in matlab.Please provide me helpful ...
332 views

### Counting human movement of exercise using ROI or pre-set passing line with OpenCV

I'm currently doing my final year Degree in computing studies. The project I'm working on is a video of a webcam or computer webcam to have 2 pre-defined ROI (Region of Interest) on top and bottom ...
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### Why do we observe band when recording CRT monitors or Flouroscent lamp via video recorder?

I understand that this has something to do with difference between refresh rate of monitor (or line frequency used by the ballast in case of Fluoroscent lamp) and frame capture rate of video recorder. ...
38 views

### Hashing a video file

Bit of a long post, but this is a complex topic: I want to hash of a series of video files so that they can be quickly checked for duplication. I know that any amount of data can be reduced to a hash,...
79 views

### Is there a way to evaluate block size when doing image processing or video processing

I am currently doing foreground segmentation in image sequences. A DCT 8 by 8 feature is extracted for each pixel. Now i want to explore dynamic block size for different scenes. Is there any rules ...