keyframe1.m

本源码为利用光流法提取视频关键帧的matlab程序实现

%%关键帧提取
clear all;
clc;
tic;%start time
shot=mmread('video\\polar-bear.mpg',1:150);%读取视频
axis off
movie(shot.frames,1,30,[45 50 0 0]);%%%播放视频
axis on
%%%%%%%%%%%%%HSoptflow(shot,n)
f=size(shot.frames,2);
flow=zeros(f);
for i=1:f-1
 [x1,y1,hs,ws]=HSoptflow(shot,i);
 for j=1:hs-1
     for k=1:ws-1
         flow(i)=flow(i)+abs(x1(j,k))+abs(y1(j,k));
     end
 end
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
figure,plot(flow),xlabel('帧号'),ylabel('视频帧光流变化曲线');%%变化曲线

[sortflow,index]=sort(flow);
for i=f:-1:1
    if sortflow(i)>=150&&abs(index(i)-index(i-1))>10
        %%%%%%%提取关键帧%%%%%%%%% 
        figure,imshow(shot.frames(1,index(i)).cdata),xlabel(strcat('第',int2str(index(i)),'关键帧'));
    end
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%