UI优化：改名文档扫描王、去掉质量选项、预览放大、智能文件名

- 软件名称改为"文档扫描王"
- 去掉JPEG质量选项，改用PNG无损写入PDF
- 预览区域从685x190放大到710x440
- 窗口高度从600增到820
- 输出文件名：图片输入→时间戳.pdf，PDF输入→modify_原名.pdf
- 删除GetJpegCodec等不再需要的代码

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

CamScanner.cs

@@ -548,7 +548,7 @@ public static class PdfHelper
     /// <summary>
     /// 将多张图像保存为单个PDF
     /// </summary>
-    public static void SaveImagesToPdf(List<Bitmap> images, string outputPath, int jpegQuality)
+    public static void SaveImagesToPdf(List<Bitmap> images, string outputPath)
     {
         Document doc = null;
         PdfWriter writer = null;
@@ -573,11 +573,7 @@ public static class PdfHelper
                 byte[] imgBytes;
                 using (MemoryStream ms = new MemoryStream())
                 {
-                    EncoderParameters ep = new EncoderParameters(1);
-                    ep.Param[0] = new EncoderParameter(
-                        System.Drawing.Imaging.Encoder.Quality, (long)jpegQuality);
-                    ImageCodecInfo codec = GetJpegCodec();
-                    bmp.Save(ms, codec, ep);
+                    bmp.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
                     imgBytes = ms.ToArray();
                 }
 
@@ -595,15 +591,6 @@ public static class PdfHelper
         }
     }
 
-    private static ImageCodecInfo GetJpegCodec()
-    {
-        ImageCodecInfo[] codecs = ImageCodecInfo.GetImageDecoders();
-        for (int i = 0; i < codecs.Length; i++)
-        {
-            if (codecs[i].FormatID == ImageFormat.Jpeg.Guid) return codecs[i];
-        }
-        return null;
-    }
 }
 
 /// <summary>
@@ -614,7 +601,6 @@ public class ScannerForm : Form
     private ListBox lstFiles;
     private Button btnAddImages, btnAddPdf, btnRemove, btnClear;
     private Button btnMoveUp, btnMoveDown, btnProcess;
-    private NumericUpDown nudQuality;
     private ProgressBar progressBar;
     private Label lblStatus;
     private PictureBox picPreview;
@@ -629,8 +615,8 @@ public class ScannerForm : Form
 
     private void InitUI()
     {
-        this.Text = "文档扫描增强工具 v2";
-        this.Size = new System.Drawing.Size(720, 600);
+        this.Text = "文档扫描王";
+        this.Size = new System.Drawing.Size(750, 820);
         this.StartPosition = FormStartPosition.CenterScreen;
         this.FormBorderStyle = FormBorderStyle.FixedDialog;
         this.MaximizeBox = false;
@@ -731,47 +717,26 @@ public class ScannerForm : Form
         };
         this.Controls.Add(btnMoveDown);
 
-        // JPEG质量
-        GroupBox grp = new GroupBox();
-        grp.Text = "输出设置";
-        grp.Location = new System.Drawing.Point(15, 222);
-        grp.Size = new System.Drawing.Size(685, 55);
-        grp.Font = new System.Drawing.Font("微软雅黑", 9f);
-        this.Controls.Add(grp);
+        // 提示
+        Label lblHint = new Label();
+        lblHint.Text = "（自动执行：透视矫正 → 倾斜校正 → 增强美化，一步到位）";
+        lblHint.Location = new System.Drawing.Point(15, 225);
+        lblHint.AutoSize = true;
+        lblHint.ForeColor = System.Drawing.Color.FromArgb(100, 100, 100);
+        lblHint.Font = new System.Drawing.Font("微软雅黑", 8f);
+        this.Controls.Add(lblHint);
 
-        Label lblQ = new Label();
-        lblQ.Text = "PDF图像质量：";
-        lblQ.Location = new System.Drawing.Point(15, 23);
-        lblQ.AutoSize = true;
-        grp.Controls.Add(lblQ);
-
-        nudQuality = new NumericUpDown();
-        nudQuality.Location = new System.Drawing.Point(110, 20);
-        nudQuality.Size = new System.Drawing.Size(60, 25);
-        nudQuality.Minimum = 50;
-        nudQuality.Maximum = 100;
-        nudQuality.Value = 92;
-        grp.Controls.Add(nudQuality);
-
-        Label lblQH = new Label();
-        lblQH.Text = "（自动执行：透视矫正 → 倾斜校正 → 增强美化，一步到位）";
-        lblQH.Location = new System.Drawing.Point(180, 23);
-        lblQH.AutoSize = true;
-        lblQH.ForeColor = System.Drawing.Color.FromArgb(100, 100, 100);
-        lblQH.Font = new System.Drawing.Font("微软雅黑", 8f);
-        grp.Controls.Add(lblQH);
-
-        // 预览
+        // 预览（正方形）
         Label lblPrev = new Label();
         lblPrev.Text = "预览：";
-        lblPrev.Location = new System.Drawing.Point(15, 285);
+        lblPrev.Location = new System.Drawing.Point(15, 248);
         lblPrev.AutoSize = true;
         lblPrev.Font = new System.Drawing.Font("微软雅黑", 9f, System.Drawing.FontStyle.Bold);
         this.Controls.Add(lblPrev);
 
         picPreview = new PictureBox();
-        picPreview.Location = new System.Drawing.Point(15, 308);
-        picPreview.Size = new System.Drawing.Size(685, 190);
+        picPreview.Location = new System.Drawing.Point(15, 270);
+        picPreview.Size = new System.Drawing.Size(710, 440);
         picPreview.SizeMode = PictureBoxSizeMode.Zoom;
         picPreview.BorderStyle = BorderStyle.FixedSingle;
         picPreview.BackColor = System.Drawing.Color.White;
@@ -779,20 +744,20 @@ public class ScannerForm : Form
 
         // 底部
         progressBar = new ProgressBar();
-        progressBar.Location = new System.Drawing.Point(15, 510);
-        progressBar.Size = new System.Drawing.Size(480, 25);
+        progressBar.Location = new System.Drawing.Point(15, 722);
+        progressBar.Size = new System.Drawing.Size(510, 25);
         this.Controls.Add(progressBar);
 
         lblStatus = new Label();
         lblStatus.Text = "就绪 - 添加文件后点击处理";
-        lblStatus.Location = new System.Drawing.Point(15, 538);
-        lblStatus.Size = new System.Drawing.Size(480, 20);
+        lblStatus.Location = new System.Drawing.Point(15, 752);
+        lblStatus.Size = new System.Drawing.Size(510, 20);
         lblStatus.ForeColor = System.Drawing.Color.DarkGray;
         this.Controls.Add(lblStatus);
 
         btnProcess = new Button();
         btnProcess.Text = "一键处理并导出PDF";
-        btnProcess.Location = new System.Drawing.Point(510, 508);
+        btnProcess.Location = new System.Drawing.Point(540, 720);
         btnProcess.Size = new System.Drawing.Size(190, 35);
         btnProcess.Font = new System.Drawing.Font("微软雅黑", 10f, System.Drawing.FontStyle.Bold);
         btnProcess.BackColor = System.Drawing.Color.FromArgb(0, 120, 215);
@@ -867,14 +832,24 @@ public class ScannerForm : Form
             return;
         }
 
+        // 默认输出文件名
+        string defaultName;
+        if (isPdfInput)
+        {
+            defaultName = "modify_" + Path.GetFileName(inputFiles[0]);
+        }
+        else
+        {
+            defaultName = DateTime.Now.ToString("yyyyMMddHHmmss") + ".pdf";
+        }
+
         SaveFileDialog sfd = new SaveFileDialog();
         sfd.Title = "保存处理后的PDF";
         sfd.Filter = "PDF|*.pdf";
-        sfd.FileName = "scanned_output.pdf";
+        sfd.FileName = defaultName;
         if (sfd.ShowDialog() != DialogResult.OK) return;
 
         string outputPath = sfd.FileName;
-        int quality = (int)nudQuality.Value;
         SetUI(false);
 
         try
@@ -927,7 +902,7 @@ public class ScannerForm : Form
             // 生成PDF
             lblStatus.Text = "正在生成PDF...";
             Application.DoEvents();
-            PdfHelper.SaveImagesToPdf(results, outputPath, quality);
+            PdfHelper.SaveImagesToPdf(results, outputPath);
 
             // 清理
             foreach (Bitmap b in sourceImages) b.Dispose();