支持GZip自动解压

src/N_m3u8DL-RE/DownloadManager/SimpleDownloadManager.cs

@@ -11,10 +11,7 @@ using N_m3u8DL_RE.Parser;
 using N_m3u8DL_RE.Parser.Mp4;
 using N_m3u8DL_RE.Util;
 using Spectre.Console;
-using Spectre.Console.Rendering;
 using System.Collections.Concurrent;
-using System.Collections.Generic;
-using System.IO;
 using System.Text;
 
 namespace N_m3u8DL_RE.DownloadManager
@@ -48,12 +45,12 @@ namespace N_m3u8DL_RE.DownloadManager
 
         private string? ReadInit(string output)
         {
+            var header = new byte[4096]; //4KB
             using (var fs = File.OpenRead(output))
             {
-                var header = new byte[4096]; //4KB
                 fs.Read(header);
-                return ReadInit(header);
             }
+            return ReadInit(header);
         }
 
         //从文件读取KEY
@@ -173,8 +170,7 @@ namespace N_m3u8DL_RE.DownloadManager
                 //读取mp4信息
                 if (result != null && result.Success) 
                 {
-                    var data = File.ReadAllBytes(result.ActualFilePath);
-                    currentKID = ReadInit(data);
+                    currentKID = ReadInit(result.ActualFilePath);
                     //从文件读取KEY
                     await SearchKeyAsync(currentKID);
                     //实时解密

src/N_m3u8DL-RE/Downloader/SimpleDownloader.cs

@@ -67,6 +67,11 @@ namespace N_m3u8DL_RE.Downloader
                 {
                     await ImageHeaderUtil.ProcessAsync(dResult.ActualFilePath);
                 }
+                //Gzip解压
+                if (dResult.GzipHeader)
+                {
+                    await OtherUtil.DeGzipFileAsync(dResult.ActualFilePath);
+                }
             }
             return dResult;
         }

src/N_m3u8DL-RE/Entity/DownloadResult.cs

@@ -13,6 +13,7 @@ namespace N_m3u8DL_RE.Entity
         public long? RespContentLength { get; set; }
         public long? ActualContentLength { get; set; }
         public bool ImageHeader { get; set; } = false; //图片伪装
+        public bool GzipHeader { get; set; } = false; //GZip压缩
         public required string ActualFilePath { get; set; }
     }
 }

src/N_m3u8DL-RE/Util/DownloadUtil.cs

@@ -108,11 +108,13 @@ namespace N_m3u8DL_RE.Util
                 var buffer = new byte[16 * 1024];
                 var size = 0;
 
-                //检测imageHeader
                 size = await responseStream.ReadAsync(buffer, cancellationTokenSource.Token);
                 speedContainer.Add(size);
                 await stream.WriteAsync(buffer, 0, size);
+                //检测imageHeader
                 bool imageHeader = ImageHeaderUtil.IsImageHeader(buffer);
+                //检测GZip（For DDP Audio）
+                bool gZipHeader = buffer.Length > 2 && buffer[0] == 0x1f && buffer[1] == 0x8b;
 
                 while ((size = await responseStream.ReadAsync(buffer, cancellationTokenSource.Token)) > 0)
                 {
@@ -125,7 +127,8 @@ namespace N_m3u8DL_RE.Util
                     ActualContentLength = stream.Length,
                     RespContentLength = contentLength,
                     ActualFilePath = path,
-                    ImageHeader= imageHeader
+                    ImageHeader= imageHeader,
+                    GzipHeader = gZipHeader
                 };
             }
             catch (OperationCanceledException oce) when (oce.CancellationToken == cancellationTokenSource.Token)

src/N_m3u8DL-RE/Util/OtherUtil.cs

@@ -2,6 +2,7 @@
 using N_m3u8DL_RE.Common.Log;
 using N_m3u8DL_RE.Enum;
 using System.CommandLine;
+using System.IO.Compression;
 using System.Text;
 
 namespace N_m3u8DL_RE.Util
@@ -110,5 +111,29 @@ namespace N_m3u8DL_RE.Util
             }
             SafeDeleteDir(parent);
         }
+
+        /// <summary>
+        /// 解压并替换原文件
+        /// </summary>
+        /// <param name="filePath"></param>
+        public static async Task DeGzipFileAsync(string filePath)
+        {
+            string deGzipFile = Path.ChangeExtension(filePath, ".tmp");
+            try
+            {
+                using (var fileToDecompressAsStream = File.OpenRead(filePath))
+                {
+                    using var decompressedStream = File.Create(deGzipFile);
+                    using var decompressionStream = new GZipStream(fileToDecompressAsStream, CompressionMode.Decompress);
+                    await decompressionStream.CopyToAsync(decompressedStream);
+                }
+                File.Delete(filePath);
+                File.Move(deGzipFile, filePath);
+            }
+            catch 
+            {
+                if (File.Exists(deGzipFile)) File.Delete(deGzipFile);
+            }
+        }
     }
 }