Esempio n. 1
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 public Track(TrackInfo trackInfo)
 {
     this.TrackInfo = trackInfo;
       this.DownloadedChunkCount = 0;
 }
Esempio n. 2
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 // Modifies track in place, and appends to mediaSamples.
 // Returns null on network failure or empty file, otherwise it returns a non-empty array.
 // The chunk file contents are returned, and are not saved to disk.
 internal static byte[] DownloadChunk(TrackInfo trackInfo, IList<MediaSample> mediaSamples, ulong chunkStartTime,
     string manifestParentPath, bool isLive, out ulong nextStartTime)
 {
     nextStartTime = 0;  // Set even if null is returned.
       string chunkUrl = trackInfo.Stream.GetChunkUrl(trackInfo.Bitrate, chunkStartTime);
       // TODO: Move TrackInfo away from Track, keep only fields necessary here, excluding ChunkList.
       byte[] downloadedBytes;  // Will be set below.
       if (manifestParentPath != null) {  // It was a local manifest, so read the chunk from a local file.
     if (!chunkUrl.StartsWith(LOCAL_URL_PREFIX)) {
       throw new Exception("ASSERT: Missing local URL prefix.");
     }
     // Example chunk URL: "http://local/QualityLevels(900000)/Fragments(video=0)".
     // TODO: Maybe this needs some further unescaping of %5A etc. (can be tested locally).
     string chunkDownloadedPath = manifestParentPath + Path.DirectorySeparatorChar +
     chunkUrl.Substring(LOCAL_URL_PREFIX.Length).Replace('/', Path.DirectorySeparatorChar);
     using (FileStream fileStream = new FileStream(chunkDownloadedPath, FileMode.Open)) {
       downloadedBytes = ReadFileStream(fileStream);
     }
     if (downloadedBytes.Length == 0) {
       Console.WriteLine();
       Console.WriteLine("Local chunk file empty: " + chunkDownloadedPath);
       return null;
     }
       } else {  // Download from the web.
     WebClient webClient = new WebClient();
     try {
       // TODO: What's the timeout on this?
       downloadedBytes = webClient.DownloadData(chunkUrl);
     } catch (WebException) {
       Thread.Sleep(isLive ? 4000 : 2000);
       try {
     downloadedBytes = webClient.DownloadData(chunkUrl);
       } catch (WebException) {
     Thread.Sleep(isLive ? 6000 : 3000);
     try {
       downloadedBytes = webClient.DownloadData(chunkUrl);
     } catch (WebException) {
       // It's an acceptable behavior to stop downloading live streams after 10 seconds.
       // If it's really live, there should be a new chunk update available every 10 seconds.
       Console.WriteLine();
       Console.WriteLine("Error downloading chunk " + chunkUrl);
       return null;
     }
       }
     }
       }
       if (downloadedBytes.Length == 0) {
     Console.WriteLine();
     Console.WriteLine("Chunk empty: " + chunkUrl);
     return null;
       }
       Fragment fragment = new Fragment(downloadedBytes, 0, downloadedBytes.Length);
       // This appends to mediaSamples.
       nextStartTime = ParseFragment(fragment, mediaSamples, trackInfo.Stream.Type, chunkStartTime);
       if (nextStartTime <= chunkStartTime) {
     throw new Exception("Found empty chunk.");
       }
       return downloadedBytes;
 }