Пример #1
0
        private TimeSpan CalculateDownloadTimeout(Segment segment)
        {
            if (!IsDynamic)
            {
                return(TimeSpan.MaxValue);
            }
            var timeout           = timeBufferDepthDefault;
            var averageThroughput = throughputHistory.GetAverageThroughput();

            if (averageThroughput > 0 && currentRepresentation.Bandwidth.HasValue && segment.Period != null)
            {
                var bandwidth            = currentRepresentation.Bandwidth.Value;
                var duration             = segment.Period.Duration.TotalSeconds;
                var segmentSize          = bandwidth * duration;
                var calculatedTimeNeeded = TimeSpan.FromSeconds(segmentSize / averageThroughput * 1.5);
                var docParams            = currentStreams.GetDocumentParameters();
                if (docParams == null)
                {
                    throw new ArgumentNullException("currentStreams.GetDocumentParameters() returns null");
                }
                var manifestMinBufferDepth =
                    docParams.Document.MinBufferTime ?? TimeSpan.Zero;
                timeout = calculatedTimeNeeded > manifestMinBufferDepth ? calculatedTimeNeeded : manifestMinBufferDepth;
            }

            return(timeout);
        }
Пример #2
0
        public void AdaptToNetConditions()
        {
            // Treat adaptive streaming as "non critical". If cannot be processed now due to lock, attempt
            // will be done at next iteration.
            if (!Monitor.TryEnter(switchStreamLock))
            {
                return;
            }

            try
            {
                if (DisableAdaptiveStreaming)
                {
                    return;
                }

                if (currentStream == null && pendingStream == null)
                {
                    return;
                }

                var streamToAdapt = pendingStream ?? currentStream;
                if (streamToAdapt.Representation.Bandwidth.HasValue == false)
                {
                    return;
                }

                var currentThroughput = throughputHistory.GetAverageThroughput();
                if (Math.Abs(currentThroughput) < 0.1)
                {
                    return;
                }

                Logger.Debug("Adaptation values:");
                Logger.Debug("  current throughput: " + currentThroughput);
                Logger.Debug("  current stream bandwidth: " + streamToAdapt.Representation.Bandwidth.Value);

                // availableStreams is sorted array by descending bandwidth
                var stream = availableStreams.FirstOrDefault(o =>
                                                             o.Representation.Bandwidth <= currentThroughput) ?? availableStreams.Last();

                if (stream.Representation.Bandwidth == streamToAdapt.Representation.Bandwidth)
                {
                    return;
                }

                Logger.Info("Changing stream to bandwidth: " + stream.Representation.Bandwidth);
                pendingStream = stream;
            }
            finally
            {
                Monitor.Exit(switchStreamLock);
            }
        }
Пример #3
0
        public void AdaptToNetConditions()
        {
            if (DisableAdaptiveStreaming)
            {
                return;
            }

            if (currentStream == null && pendingStream == null)
            {
                return;
            }

            var streamToAdapt = pendingStream ?? currentStream;

            if (streamToAdapt.Representation.Bandwidth.HasValue == false)
            {
                return;
            }

            var currentThroughput = throughputHistory.GetAverageThroughput();

            if (Math.Abs(currentThroughput) < 0.1)
            {
                return;
            }

            Logger.Debug("Adaptation values:");
            Logger.Debug("  current throughput: " + currentThroughput);
            Logger.Debug("  current stream bandwidth: " + streamToAdapt.Representation.Bandwidth.Value);

            // availableStreams is sorted array by descending bandwidth
            var stream = availableStreams.FirstOrDefault(o =>
                                                         o.Representation.Bandwidth <= currentThroughput) ?? availableStreams.Last();

            if (stream.Representation.Bandwidth == streamToAdapt.Representation.Bandwidth)
            {
                return;
            }

            Logger.Info("Changing stream to bandwidth: " + stream.Representation.Bandwidth);
            pendingStream = stream;
        }