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【MATLAB】读取视频，提取视频每一帧特征值并存成EXCEL，并保存个别图像

news 2026/6/4 8:24:03

1、读取视频
2、对视频尺寸进行预处理到4K
3、分析每帧特征
4、将每帧特征存储到Excel表格
5、将特殊画面存进对应文件夹里

clear;close all;clc;%初始化fileName='grayscale.mp4';%视频名称filepath=strcat('./input/',fileName);obj=VideoReader(filepath);numFrames=obj.NumFrames;% 帧的总数h=obj.Width;v=obj.Height;vh_th=0.7;%16：9差异设置，abs(h/v-16/9)<vh_th不加黑框frame_UD=zeros(2160,3840,3,'uint8');YCbCr=zeros(2160,3840,'double');frame_Falg=zeros(numFrames,4,'double');APL=zeros(1,1,'double');savepath=strcat('./output/',fileName(1:end-4));if~exist(savepath,'dir')savepath_status=mkdir(savepath);%如果路径不存在则新建一个endfork=1:numFrames% 读取数据frame=read(obj,k);%视频大小预处理ifabs(h/v-16/9)<vh_th frame_UD=imresize(frame,[2160,3840],'bilinear');%16:9插值到4Kblack_add=0;elseifh>v frame_new_h=imresize(frame,[v,3840],'bilinear');start=fix((2160-v)/2);frame_UD(start:start+v-1,:,:)=frame_new_h;black_add=(2160-v)*3840;elseframe_new_v=imresize(frame,[2160,h],'bilinear');start=fix((3840-h)/2);frame_UD(:,start:start+h-1,:)=frame_new_v;black_add=(3840-h)*2160;endend%APL generateYCbCr=0.299*frame_UD(:,:,1)+0.587*frame_UD(:,:,2)+0.114*frame_UD(:,:,3);APL=mean2(YCbCr)/255;%0~4pixel countifAPL>=0&&APL<0.2Gray_range=4;elseifAPL>=0.2&&APL<0.4Gray_range=5;elseifAPL>=0.4&&APL<0.6Gray_range=6;elseifAPL>=0.6&&APL<0.8Gray_range=8;elseifAPL>=0.8&&APL<=1Gray_range=10;elseray_range=10;endGray_cnt=fix(sum(sum(sum(frame_UD<Gray_range)))/3);ifGray_cnt>(8295+black_add)grayscale_gradient_Flag=1;elsegrayscale_gradient_Flag=0;endframe_Falg(k,1)=k;frame_Falg(k,2)=APL;frame_Falg(k,3)=Gray_cnt;frame_Falg(k,4)=grayscale_gradient_Flag;% imshow(frame_UD);%显示帧ifgrayscale_gradient_Flag==1WritePath=strcat('./output/',fileName(1:end-4),'/',num2str(k),'.bmp');imwrite(frame_UD,WritePath);% 保存帧endendWritepath_excel=strcat('./output/',fileName(1:end-4),'_analysis.xlsx');%方式1，速度慢%Writdetail_excel = {'Frame num', 'APL', 'Gray count','grayscale_like' };% for k=1:numFrames% Writdetail_excel (k+1,:)={frame_Falg(k,1),frame_Falg(k,2),frame_Falg(k,3),frame_Falg(k,4)};% end%方式2，矩阵操作加速Writdetail_excel(1,:)={'Frame num','APL','Gray count','grayscale_like'};Writdetail_excel(2:numFrames+1,:)=num2cell(frame_Falg(:,:));writecell(Writdetail_excel,Writepath_excel);disp('Analysis Done!');