图片压缩兼修改md5

概述

一个桌面程序，能修改图片的尺寸和质量，并且通过加水印的方式修改图片的md5等值。

详细

代码下载：http://www.demodashi.com/demo/13498.html

一、程序截图

TIM截图20180629143904.jpg

二、实现过程

实现思路：

1、编写界面

2、编写具体的按钮事件

3、重点是图片处理方法，然后将这些方法连接到按钮事件上面

4、测试运行。

具体代码如下：

1、入口是两个开始按钮的监听事件方法

//选择图片所在目录
private void button1_Click(object sender, EventArgs e)
{
    FolderBrowserDialog dialog = new FolderBrowserDialog();
    dialog.Description = "请选择图片所在文件夹";
    if (dialog.ShowDialog() == DialogResult.OK)
    {
        if (string.IsNullOrEmpty(dialog.SelectedPath))
        {
            label3.Text = "文件夹路径不能为空";
            return;
        }
        label1.Text = dialog.SelectedPath;
        source = dialog.SelectedPath;
        }
}
//选择图片所在目录
private void button2_Click(object sender, EventArgs e)
{
    FolderBrowserDialog dialog = new FolderBrowserDialog();
    dialog.Description = "请选择输出文件夹";
    if (dialog.ShowDialog() == DialogResult.OK)
    {
        if (string.IsNullOrEmpty(dialog.SelectedPath))
        {
            label3.Text = "文件夹路径不能为空";
            return;
        }
        label2.Text = dialog.SelectedPath;
        output = dialog.SelectedPath;
    }
}
 
//单层目录开始按钮监听
//按方法用于选择单个目录下的所有图片文件，并调用ApplyWaterMark方法进行图像处理
private void btnOk_Click(object sender, EventArgs e)
{
    label3.ForeColor = Color.Black;
    if (string.IsNullOrEmpty(source))
    {
        label3.ForeColor = Color.Red;
        label3.Text = "请选择原文件夹";
        return;
    }
    if (string.IsNullOrEmpty(output))
    {
        label3.ForeColor = Color.Red;
        label3.Text = "请选择输出文件夹";
        return;
    }
    var files = Directory.GetFiles(source);
    foreach (var file in files)
    {
        ApplyWaterMark(file, output);
        label3.Text = "正在修改" + file;
    }
    label3.ForeColor = Color.Red;
    label3.Text = "完成";
    source = string.Empty;
    output = string.Empty;
}
 
//双层目录开始按钮监听
//该方法用于父目录下还有一层子目录，子目录下才是图片文件的情况。可以批量修改多个文件夹的图片
private void btnOk2_Click(object sender, EventArgs e)
{
    label3.ForeColor = Color.Black;
    if (string.IsNullOrEmpty(source))
    {
        label3.ForeColor = Color.Red;
        label3.Text = "请选择原文件夹";
        return;
    }
    if (string.IsNullOrEmpty(output))
    {
        label3.ForeColor = Color.Red;
        label3.Text = "请选择输出文件夹";
        return;
    }
    var dirs = Directory.GetDirectories(source); //先打开父目录
    foreach (var dir in dirs) //遍历子目录
    {
        foreach (var file in Directory.GetFiles(dir))
        {
            var dirInfo = new DirectoryInfo(dir);
            var dirName = dirInfo.Name;
            var outputDirName = Path.Combine(output, dirName);
            ApplyWaterMark(file, outputDirName);
            label3.Text = "正在修改" + file;
        }
    }
    label3.ForeColor = Color.Red;
    label3.Text = "完成";
    source = string.Empty;
    output = string.Empty;
}

2、图像处理的核心代码

private void ApplyWaterMark(string file, string dir)
{
    try
    {
        var info = new FileInfo(file);
        var name = info.Name;
        Image Im = Image.FromFile(file);
        var rate = (int)compressRate.Value == 0 ? 1 : (int)compressRate.Value;//读取图片压缩控件设置的倍数，最大值10
        var newImage = new Bitmap(Im,Im.Width/rate,Im.Height/rate);//源图片长宽除以该倍数，缩放图片
        Graphics g = Graphics.FromImage(newImage);
        // 创建 solid brush 往图片写水印
        Brush myBrush = new SolidBrush(Color.FromArgb(1, Color.LightSteelBlue));
        var f = new Font(FontFamily.GenericSerif, 1);
        var x = (int)(coX.Value); //读取水印坐标设置的X轴值
        var y = (int)(coY.Value); //读取水印坐标设置的Y轴值
        g.DrawString(".", f, myBrush, new Point(x, y));
        if (!Directory.Exists(dir)) //创建图片的输出目录
        {
            Directory.CreateDirectory(dir);
        }
        //初始化jpg图片解码器
        ImageCodecInfo jpgEncoder = GetEncoder(ImageFormat.Jpeg);
        Encoder myEncoder = Encoder.Quality;
        EncoderParameters myEncoderParameters = new EncoderParameters(1);
         
        var qualityNum = quality.Value; //读取图片质量控件设置的值，最大值为100
        EncoderParameter myEncoderParameter = new EncoderParameter(myEncoder, (long)qualityNum);
        myEncoderParameters.Param[0] = myEncoderParameter;
        newImage.Save(Path.Combine(dir, name), jpgEncoder, myEncoderParameters);
         
        Im.Dispose();
        newImage.Dispose();
        g.Dispose();
        myBrush.Dispose();
    }
    catch (Exception ex)
    {
        File.AppendAllText("error.txt", dir + "," + ex.Message);
    }
}
 
private ImageCodecInfo GetEncoder(ImageFormat format)
{
    ImageCodecInfo[] codecs = ImageCodecInfo.GetImageDecoders();
    foreach (ImageCodecInfo codec in codecs)
    {
        if (codec.FormatID == format.Guid)
    {
        return codec;
    }
}
    return null;
}