当环境变量RE_KEEP_IMAGE_SEGMENTS=1时, 跳过字幕转换为PNG后删除原始文件的逻辑 (#625)

Author: nilaoda

src/N_m3u8DL-RE/CommandLine/CommandInvoker.cs

@@ -17,7 +17,7 @@ namespace N_m3u8DL_RE.CommandLine;
 
 internal static partial class CommandInvoker
 {
-    public const string VERSION_INFO = "N_m3u8DL-RE (Beta version) 20241216";
+    public const string VERSION_INFO = "N_m3u8DL-RE (Beta version) 20250311";
 
     [GeneratedRegex("((best|worst)\\d*|all)")]
     private static partial Regex ForStrRegex();

src/N_m3u8DL-RE/Config/EnvConfigKey.cs

@@ -0,0 +1,22 @@
+namespace N_m3u8DL_RE.Config;
+
+/// <summary>
+/// 通过配置环境变量来实现更细节地控制某些逻辑
+/// </summary>
+public static class EnvConfigKey
+{
+    /// <summary>
+    /// 当此值为1时, 在图形字幕处理逻辑中PNG生成后不再删除m4s文件
+    /// </summary>
+    public const string ReKeepImageSegments = "RE_KEEP_IMAGE_SEGMENTS";
+    
+    /// <summary>
+    /// 控制启用PipeMux时, 具体ffmpeg命令行
+    /// </summary>
+    public const string ReLivePipeOptions = "RE_LIVE_PIPE_OPTIONS";
+    
+    /// <summary>
+    /// 控制启用PipeMux时, 非Windows环境下命名管道文件的生成目录
+    /// </summary>
+    public const string ReLivePipeTmpDir = "RE_LIVE_PIPE_TMP_DIR";
+}

src/N_m3u8DL-RE/DownloadManager/SimpleDownloadManager.cs

@@ -454,7 +454,9 @@ await Parallel.ForEachAsync(segments, options, async (seg, _) =>
             // 处理图形字幕
             await SubtitleUtil.TryWriteImagePngsAsync(finalVtt, tmpDir);
 
-            foreach (var item in files) File.Delete(item);
+            var keepSegments = OtherUtil.GetEnvironmentVariable(EnvConfigKey.ReKeepImageSegments);
+            if (keepSegments != "1")
+                foreach (var item in files) File.Delete(item);
             FileDic.Clear();
             var index = 0;
             var path = Path.Combine(tmpDir, index.ToString(pad) + ".fix.vtt");
@@ -506,7 +508,9 @@ await Parallel.ForEachAsync(segments, options, async (seg, _) =>
             // 处理图形字幕
             await SubtitleUtil.TryWriteImagePngsAsync(finalVtt, tmpDir);
 
-            foreach (var item in files) File.Delete(item);
+            var keepSegments = OtherUtil.GetEnvironmentVariable(EnvConfigKey.ReKeepImageSegments);
+            if (keepSegments != "1")
+                foreach (var item in files) File.Delete(item);
             FileDic.Clear();
             var index = 0;
             var path = Path.Combine(tmpDir, index.ToString(pad) + ".fix.vtt");

src/N_m3u8DL-RE/Util/PipeUtil.cs

@@ -3,6 +3,7 @@
 using System.Diagnostics;
 using System.IO.Pipes;
 using System.Text;
+using N_m3u8DL_RE.Config;
 
 namespace N_m3u8DL_RE.Util;
 
@@ -43,11 +44,11 @@ public static async Task<bool> StartPipeMuxAsync(string binary, string[] pipeNam
 
     public static bool StartPipeMux(string binary, string[] pipeNames, string outputPath)
     {
-        string dateString = DateTime.Now.ToString("o");
-        StringBuilder command = new StringBuilder("-y -fflags +genpts -loglevel quiet ");
+        var dateString = DateTime.Now.ToString("o");
+        var command = new StringBuilder("-y -fflags +genpts -loglevel quiet ");
 
-        string customDest = OtherUtil.GetEnvironmentVariable("RE_LIVE_PIPE_OPTIONS");
-        string pipeDir = OtherUtil.GetEnvironmentVariable("RE_LIVE_PIPE_TMP_DIR", Path.GetTempPath());
+        var customDest = OtherUtil.GetEnvironmentVariable(EnvConfigKey.ReLivePipeOptions);
+        var pipeDir = OtherUtil.GetEnvironmentVariable(EnvConfigKey.ReLivePipeTmpDir, Path.GetTempPath());
 
         if (!string.IsNullOrEmpty(customDest))
         {
@@ -63,7 +64,7 @@ public static bool StartPipeMux(string binary, string[] pipeNames, string output
                 command.Append($" -i \"{Path.Combine(pipeDir, item)}\" ");
         }
 
-        for (int i = 0; i < pipeNames.Length; i++)
+        for (var i = 0; i < pipeNames.Length; i++)
         {
             command.Append($" -map {i} ");
         }