칼만 필터를 사용하여 비디오에서 배경을 전경에서 분리해야합니다. 누군가 제가 따라야 할 리소스 나 코드 예제를 줄 수 있습니까?배경 빼기 칼만 필터를 사용한 전경 검출
업데이트 : 여기에 좋은 예제가 있습니다. Traffic detection. 트래픽 탐지에 탁월하게 작용했지만 사람 추출을 위해 다시 적용하고 싶습니다.
다음1. alpha = learning constant
2. K= #of guassians in the mixture
3. T = min. portion of background
4. initVariance = initial variance
5. pixelThresh = threshold condition for computing adaptive process on pixel
이 주 파일의 개요입니다 (경우에 당신이 개요를 원하는)
function foregroundEstimation(movie)
%Load video into memory and prepare output video for writing
v = VideoReader(movie);
numFrames = 150;
foregroundVideo = VideoWriter('foreground.avi');
open(foregroundVideo);
%video constants
initFrame = read(v,1);
global height;
global width;
height = size(initFrame,1);
width = size(initFrame,2);
%initialize GMM parameters: (based upon Stauffer notation)
%http://www.ai.mit.edu/projects/vsam/Publications/stauffer_cvpr98_track.pdf
% alpha = learning constant
% K= #of guassians in the mixture
% T = min. portion of background
% initVariance = initial variance
% pixelThresh = threshold condition for computing adaptive process on pixel
alpha=0.05; % 0.05
K=5; % 5
global T; % T = 0.8
T=0.8;
global initVariance;
initVariance=75; % 75
pixelThresh=45; % 45
referenceDistance = 40; % 40 %shortcut to speed up processing time. Compare current pixel to pixel referenceDistance frames back and skip adaptive process if similar. Downside is doesn't collect background evidence as well.
sideWeight = (K-1)/(1-T);
global matchThres;
matchThres = sqrt(3);
global ccThreshold;
ccThreshold = 9000; % 5000
global deltaT;
deltaT = 1;
global numParticles;
numParticles = 100;
trackingOn = 0; % will superimpose tracking color marker on detected vehicles in output video. tackingOn should equal 1 or 0
prevCentSize = 0;
%structures to pass information between frames for detection purposes.
field = 'f';
filterValue = {[];[];};
prevFilter = struct(field,filterValue);
modelValue = {[];prevFilter};
prevModel = struct(field,modelValue);
%initiailze video process components
initColorBoxes();
foreFrame = zeros(height,width,3);
backFrame = zeros(height,width,3);
%map represents pixels at a given frame to perform adaptive process
pixThreshMap = ones(height,width);
%individual pixel process components
pixel = zeros(3,1);
pixMean = zeros(3,1,K);
pixVar = ones(1,K);
pixWeight = zeros(1,K);
%global pixel process components
globalWeight = (ones(height,width,K)/sideWeight);
globalWeight(:,:,1) = T;
%globalWeight = (ones(height,width,K)/K);
globalMean = zeros(height,width,3,K);
globalVar = ones(height,width,K);
%=====================================================
%Extract Foreground and Background by K-mixture model
%=====================================================
%initialize g-mixture model
globalVar = globalVar*initVariance;
for k=1:K
globalMean(:,:,1,k)=initFrame(:,:,1);
globalMean(:,:,2,k)=initFrame(:,:,2);
globalMean(:,:,3,k)=initFrame(:,:,3);
end;
distVec = zeros(numFrames,1);
%adaptive g-mixture background segmentation
for frameIndex=2:numFrames
%get current frame and the refernece frame
%tic;
frameIndex
currentFrame = double(read(v,frameIndex));
if (frameIndex<=referenceDistance)
referenceFrame= double(read(v,1));
else
referenceFrame= double(read(v,frameIndex-referenceDistance));
end;
frameDifference = abs(currentFrame - referenceFrame);
%creates map of pixel locations where we will perform adaptive process. Based
%upon threshold that detects low change regions based on previous frame in
%order to save computation.
pixThreshMap = min(sum(+(frameDifference(:,:,:)>pixelThresh),3),1);
for index=1:3
backFrame(:,:,index)=(+(pixThreshMap(:,:)==0)).*currentFrame(:,:,index);
end;
%extract the parts considered "stable background" from current frame
%reset foreground frame
foreFrame = ones(height,width,3)*255;
%gaussian mixture matching & model updating
[i,j]=find(pixThreshMap(:,:)==1);
%loop through every pixel location where adaptive process should be performed
for k = 1:size(i,1)
pixel = reshape(currentFrame(i(k),j(k),:),3,1);
pixMean = reshape(globalMean(i(k),j(k),:,:),3,1,K);
pixVar = reshape(globalVar(i(k),j(k),:,:),1,K);
pixWeight=reshape(globalWeight(i(k),j(k),:),1,K);
%update gaussian mixture according to new pix value
match=matchingCriterion(pixMean,pixVar,pixel);
matchWeight = 0;
if(match>0)
%match found so update weights/normalize
pixWeight = (1-alpha)*pixWeight;
pixWeight(match)= pixWeight(match) + alpha;
pixWeight = pixWeight/sum(pixWeight);
matchWeight = pixWeight(1,match);
%NOTE ALPHA SHOULD BE REPACED WITH SOME KIND OF RHO EVENTUALLY
%WHERE RHO IS PRODUCT OF ALPHA AND CONDITIONAL PROBABILITY MEASURE
%update variance
pixVar(:,match) = (1-alpha)*pixVar(:,match) + ...
alpha*(pixel - pixMean(:,:,match))'*(pixel-pixMean(:,:,match));
%update mean
pixMean(:,:,match) = (1-alpha)*pixMean(:,:,match) + alpha*pixel;
else
%no match currently found.
%replace one with lowest sigma value
rankVector = pixWeight./sqrt(pixVar(1,:));
[mini minIndex] = min(rankVector);
pixMean(:,:,minIndex) = pixel;
pixVar(:,minIndex) = initVariance;
end
%rerank all pixel components
rankCriterionVector = pixWeight./sqrt(pixVar(1,1,:));
[rankSort rankIndex] = sort(rankCriterionVector);
pixMean = pixMean(rankIndex);
pixVar = pixVar(rankIndex);
pixWeight = pixWeight(rankIndex);
%repopulate global structures with updated values
globalWeight(i(k),j(k),:) = pixWeight(:,1);
globalMean(i(k),j(k),:,:) = pixMean(:,1,:);
globalVar(i(k),j(k),:,:) = pixVar(:,:,:);
%now need to perform the background segmentation based upon weight
%threshold
bgIndex = segmentBackground(pixWeight);
if(ismember(matchWeight, pixWeight))
matchIndex = find(pixWeight == matchWeight,1);
else
matchIndex = 0;
end
if((matchIndex>=bgIndex) || (matchIndex == 0))
%also check against initFrame for match
%NOTE CHANGE
if(initMatch(initFrame(i(k),j(k),:),pixel) == 0)
foreFrame(i(k),j(k),:) = pixel;
end
end
end
%Now write foreground frame to foreground estimation video
contrastFrame = foreFrame/max(abs(foreFrame(:)));
%remove all connected components associated with foreground objects that are smaller than what we expect a vehicle should be.
[cleanFrame centroids]= connectedComponentCleanup(contrastFrame);
if(trackingOn == 1)
if(size(centroids,1) > prevCentSize)
prevModel = addModel(prevModel, centroids, height, width);
elseif (size(centroids,1) < prevCentSize)
prevModel = removeModel(prevModel, centroids, height, width);
end
if(size(centroids,1) > 0)
%implies there is a car in frame for tracking
[curModel orderedCentroids] = vehicleTracking(centroids, prevModel);
prevModel = curModel;
trackFrame = colorBox(cleanFrame, curModel,orderedCentroids, height, width);
else
trackFrame = cleanFrame;
end
else
trackFrame = cleanFrame;
end
writeVideo(foregroundVideo,trackFrame);
prevCentSize = size(centroids,1);
end
: 나는의 예를 들어 적응해야 할 몇 가지 변수를 발견했습니다
감사합니다.
** 관련 예를 들어 볼 수 있었다, 프레임 사이의 객체를 추적하는 그 후 사용할 수 있습니다 : - ** http://www.mathworks.com/help/vision/examples/using -kalman-filter-for-object-tracking.html –