优化图形字幕处理 #109

src/N_m3u8DL-RE/CommandLine/CommandInvoker.cs

@@ -18,7 +18,7 @@ namespace N_m3u8DL_RE.CommandLine
 {
     internal partial class CommandInvoker
     {
-        public const string VERSION_INFO = "N_m3u8DL-RE (Beta version) 20230111";
+        public const string VERSION_INFO = "N_m3u8DL-RE (Beta version) 20230323";
 
         [GeneratedRegex("((best|worst)\\d*|all)")]
         private static partial Regex ForStrRegex();

src/N_m3u8DL-RE/DownloadManager/SimpleDownloadManager.cs

@@ -106,7 +106,7 @@ namespace N_m3u8DL_RE.DownloadManager
             ConcurrentDictionary<MediaSegment, DownloadResult?> FileDic = new();
 
             var segments = streamSpec.Playlist?.MediaParts.SelectMany(m => m.MediaSegments);
-            if (segments == null) return false;
+            if (segments == null || !segments.Any()) return false;
             if (segments.Count() == 1) speedContainer.SingleSegment = true;
 
             var type = streamSpec.MediaType ?? Common.Enum.MediaType.VIDEO;
@@ -441,19 +441,7 @@ namespace N_m3u8DL_RE.DownloadManager
                 var files = FileDic.OrderBy(s => s.Key.Index).Select(s => s.Value).Select(v => v!.ActualFilePath).ToArray();
 
                 //处理图形字幕
-                if (finalVtt.Cues.All(v => v.Payload.StartsWith("Base64::")))
+                await SubtitleUtil.TryWriteImagePngsAsync(finalVtt, tmpDir);
-                {
-                    Logger.WarnMarkUp(ResString.processImageSub);
-                    var _pad = "0".PadLeft(finalVtt.Cues.Count().ToString().Length, '0');
-                    var _i = 0;
-                    foreach (var img in finalVtt.Cues)
-                    {
-                        var base64 = img.Payload[8..];
-                        var name = _i++.ToString(_pad) + ".png";
-                        await File.WriteAllBytesAsync(Path.Combine(tmpDir, name), Convert.FromBase64String(base64));
-                        img.Payload = name;
-                    }
-                }
 
                 foreach (var item in files) File.Delete(item);
                 FileDic.Clear();
@@ -504,19 +492,7 @@ namespace N_m3u8DL_RE.DownloadManager
                 var files = FileDic.OrderBy(s => s.Key.Index).Select(s => s.Value).Select(v => v!.ActualFilePath).ToArray();
 
                 //处理图形字幕
-                if (finalVtt.Cues.All(v => v.Payload.StartsWith("Base64::")))
+                await SubtitleUtil.TryWriteImagePngsAsync(finalVtt, tmpDir);
-                {
-                    Logger.WarnMarkUp(ResString.processImageSub);
-                    var _pad = "0".PadLeft(finalVtt.Cues.Count().ToString().Length, '0');
-                    var _i = 0;
-                    foreach (var img in finalVtt.Cues)
-                    {
-                        var base64 = img.Payload[8..];
-                        var name = _i++.ToString(_pad) + ".png";
-                        await File.WriteAllBytesAsync(Path.Combine(tmpDir, name), Convert.FromBase64String(base64));
-                        img.Payload = name;
-                    }
-                }
 
                 foreach (var item in files) File.Delete(item);
                 FileDic.Clear();

src/N_m3u8DL-RE/DownloadManager/SimpleLiveRecordManager2.cs

@@ -122,7 +122,7 @@ namespace N_m3u8DL_RE.DownloadManager
             {
                 name = GetUnixTimestamp(segment.DateTime!.Value).ToString();
             }
-            else if (hls && segment.Index > 10)
+            else if (hls)
             {
                 name = segment.Index.ToString();
             }
@@ -200,6 +200,7 @@ namespace N_m3u8DL_RE.DownloadManager
                 //TryReceiveAll可以稍微缓解一下
                 source.TryReceiveAll(out IList<List<MediaSegment>>? segmentsList);
                 var segments = segmentsList!.SelectMany(s => s);
+                if (segments == null || !segments.Any()) continue;
                 var segmentsDuration = segments.Sum(s => s.Duration);
                 Logger.DebugMarkUp(string.Join(",", segments.Select(sss => GetSegmentName(sss, false, false))));
 
@@ -594,6 +595,10 @@ namespace N_m3u8DL_RE.DownloadManager
                                 File.Delete(inputFilePath);
                             }
                         }
+
+                        //处理图形字幕
+                        await SubtitleUtil.TryWriteImagePngsAsync(currentVtt, tmpDir);
+
                         var subText = currentVtt.ToVtt();
                         if (outputExt == ".srt")
                         {

src/N_m3u8DL-RE/Util/SubtitleUtil.cs

@@ -0,0 +1,40 @@
+using N_m3u8DL_RE.Common.Entity;
+using N_m3u8DL_RE.Common.Log;
+using N_m3u8DL_RE.Common.Resource;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace N_m3u8DL_RE.Util
+{
+    internal class SubtitleUtil
+    {
+        /// <summary>
+        /// 写出图形字幕PNG文件
+        /// </summary>
+        /// <param name="finalVtt"></param>
+        /// <param name="tmpDir">临时目录</param>
+        /// <returns></returns>
+        public static async Task<bool> TryWriteImagePngsAsync(WebVttSub? finalVtt, string tmpDir)
+        {
+            if (finalVtt != null && finalVtt.Cues.Any(v => v.Payload.StartsWith("Base64::")))
+            {
+                Logger.WarnMarkUp(ResString.processImageSub);
+                var _i = 0;
+                foreach (var img in finalVtt.Cues.Where(v => v.Payload.StartsWith("Base64::")))
+                {
+                    var name = $"{_i++}.png";
+                    var dest = "";
+                    for (; File.Exists(dest = Path.Combine(tmpDir, name)); name = $"{_i++}.png") ;
+                    var base64 = img.Payload[8..];
+                    await File.WriteAllBytesAsync(dest, Convert.FromBase64String(base64));
+                    img.Payload = name;
+                }
+                return true;
+            }
+            else return false;
+        }
+    }
+}