Image_Processing

opencv中感兴趣区域以及mask的使用

不规则区域提取

使用预先定义的ROI Matlab进行图像裁剪

CV2

RGB =(height, width, 3)

图片读取cv2.imread()第一个参数是文件路径，第二个参数指定读取方式

import numpy as np
import cv2
# 以灰度模式读取图片
img = cv2.imread('lena.jpg',0)   //  cv2.IMREAD_GRAYSCALE

• cv2.IMREAD_COLOR：加载彩色图片，这个是默认参数。
• cv2.IMREAD_GRAYSCALE：以灰度模式加载图片。
• cv2.IMREAD_UNCHANGED：包括alpha。
• 上面三个flag分别对应的值为1，0，-1

使用cv2.imshow()显示一个图像窗口，窗口大小根据图像自动调整。第一个参数是窗口名称，第二个参数是图片。

使用函数cv2.imwrite()保存图像到文件,第一个参数是文件名，第二个参数是你要保存的文件

使用cv2.resize(img,(width, height))来改变图像大小。

VIDEOS

从视频中提取帧 ref

# coding=utf-8

# 全局变量
VIDEO_PATH = './1.avi' # 视频地址
EXTRACT_FOLDER = './extract_folder' # 存放帧图片的位置
EXTRACT_FREQUENCY = 100 # 帧提取频率


def extract_frames(video_path, dst_folder, index):
    # 主操作
    import cv2
    video = cv2.VideoCapture()
    if not video.open(video_path):
        print("can not open the video")
        exit(1)
    count = 1
    while True:
        _, frame = video.read()
        if frame is None:
            break
        if count % EXTRACT_FREQUENCY == 0:
            save_path = "{}/{:>03d}.jpg".format(dst_folder, index)
            cv2.imwrite(save_path, frame)
            index += 1
        count += 1
    video.release()
    # 打印出所提取帧的总数
    print("Totally save {:d} pics".format(index-1))


def main():
    # 递归删除之前存放帧图片的文件夹，并新建一个
    import shutil
    try:
        shutil.rmtree(EXTRACT_FOLDER)
    except OSError:
        pass
    import os
    os.mkdir(EXTRACT_FOLDER)
    # 抽取帧图片，并保存到指定路径
    extract_frames(VIDEO_PATH, EXTRACT_FOLDER, 1)


if __name__ == '__main__':
    main()

import cv2
import shutil
import os

dataset = "handwaving"
inpath = "/Users/daniel/Desktop/%s/"%dataset
outpath = "/Users/daniel/Downloads/Nutstore/PythonFile/DATASET/KTH/%s/"%dataset

def extract_frames(video_path,dst_folder,index):
    video = cv2.VideoCapture()
    if not video.open(video_path):
        print("can not open the video")
        exit(1)
    success = True
    while success:
        success, frame = video.read()
        save_path = dst_folder+"%d.png"%index
        cv2.imwrite(save_path, frame)
        index += 1
    video.release()
    # 打印出所提取帧的总数
    print("Totally save {:d} pics".format(index-1))
    return index

def main():
    index = 1
    try:
        shutil.rmtree(outpath)
    except OSError:
        pass
    if not os.path.exists(outpath):
        os.makedirs(outpath)
    for i in range(1, 21):
        for j in range(1, 5):
            video_path = inpath + "person%02d_handwaving_d%d_uncomp.avi" % (i, j)
            index = extract_frames(video_path,outpath,index)

if __name__=="__main__":
    main()

Depth Images

rgbd images processing

Loading and Visualizing Kinect Depth images in Matlab

MSR3D-Daily Activities Dataset

clear;close all;clc;
binPath = '/Users/daniel/Downloads/Nutstore/PythonFile/DATASET/msr3d/Depth/';
output_path = '/Users/daniel/Downloads/Nutstore/PythonFile/DATASET/msr3d/Depth_Image/';
idx = 0;
for si = 1:1
    for ai = 1:1
        for ei = 1:1
            %%%%%%%%%%%%%
            %%%%%%%%%%%%%
            acsr = num2str(ai,'%02d');
            susr = num2str(si,'%02d');
            exsr = num2str(ei,'%02d');
            %%%%%% getsr(ai,si,ei) convert ai,si,ei to double bits
            %%%%%% for example, if ai=3, acsr is 03
            %%%%%%%%%%%

            binfile = [binPath,'a',acsr,'_s',susr,'_e',exsr,'_depth.bin']; 
            if ~exist(binfile,'file')
                disp('error');
                continue;
            end

            fileread = fopen(binfile);      
            if fileread<0
               disp('no such file.');
               return;
            end

       
            header = fread(fileread,3,'uint=>uint');
            nnof = header(1); ncols = header(2); nrows = header(3);
            

            depths = zeros(ncols, nrows, nnof);
            for f = 1:nnof
                idx = idx+1;
                fprintf('Processing %d/10, %d/16, %d/2, %d/%d\n',si,ai,ei,f,nnof);
                frame = zeros( ncols, nrows);
                for row = 1:nrows
                    tempRow = fread(fileread, ncols, 'uint=>uint');
                    tempRowID = fread(fileread, ncols, 'uint8');%%%%%
                    frame(:,row) = tempRow;
                end
                depth(:,:,f) = frame;
                [m,n] = size(depth(:,:,f));
                
                pic_name = [output_path,num2str(idx),'.jpg'];
                pic = imrotate(depth(:,:,f),270);
                %imshow(depth(:,:,f));
                %imwrite(uint8(pic),pic_name);
                
                
                %plot3k(depth(:,:,1));
                
                
%                 fig = imagesc(depth(:,:,1)); axis off; % truesize;
%                 title('Depth in color map');
%                 colormap parula;
%                 c = colorbar; c.Label.String = 'Distance in mm';
%                 clear tempRow tempRowID;
                
                
%                 [counts,binLocations] = imhist(depth(:,:,1),4000);
%                 binLocations = binLocations(1:4000,1);
%                 bar( binLocations,counts); xlim([450 4000])
%                 title('Histogram of depth values');
            end


            fclose(fileread);
        end
    end
end