/// <summary>
/// Continually decodes the available packet buffer to have as
/// many frames as possible in each frame queue and
/// up to the MaxFrames on each component
/// </summary>
internal void RunFrameDecodingWorker()
{
try
{
// State variables
var decodedFrameCount = 0;
var wallClock = TimeSpan.Zero;
var rangePercent = 0d;
var isInRange = false;
// Holds the main media type
var main = Container.Components.Main.MediaType;
// Holds the auxiliary media types
var auxs = Container.Components.MediaTypes.Where(x => x != main).ToArray();
// Holds all components
var all = Container.Components.MediaTypes.ToArray();
var isBuffering = false;
var resumeClock = false;
var hasPendingSeeks = false;
MediaComponent comp = null;
MediaBlockBuffer blocks = null;
while (IsTaskCancellationPending == false)
{
#region 1. Setup the Decoding Cycle
// Singal a Seek starting operation
hasPendingSeeks = Commands.PendingCountOf(MediaCommandType.Seek) > 0;
if (IsSeeking == false && hasPendingSeeks)
{
IsSeeking = true;
RaiseSeekingStartedEvent();
}
// Execute the following command at the beginning of the cycle
Commands.ProcessNext();
// Signal a Seek ending operation
hasPendingSeeks = Commands.PendingCountOf(MediaCommandType.Seek) > 0;
if (IsSeeking == true && hasPendingSeeks == false)
{
SnapVideoPosition(Clock.Position);
IsSeeking = false;
// Call the seek method on all renderers
foreach (var kvp in Renderers)
{
kvp.Value.Seek();
}
RaiseSeekingEndedEvent();
}
// Wait for a seek operation to complete (if any)
// and initiate a frame decoding cycle.
SeekingDone?.WaitOne();
// Initiate the frame docding cycle
FrameDecodingCycle?.Reset();
// Set initial state
wallClock = Clock.Position;
decodedFrameCount = 0;
#endregion
#region 2. Main Component Decoding
// Capture component and blocks for easier readability
comp = Container.Components[main];
blocks = Blocks[main];
// Handle the main component decoding; Start by checking we have some packets
if (comp.PacketBufferCount > 0)
{
// Detect if we are in range for the main component
isInRange = blocks.IsInRange(wallClock);
if (isInRange == false)
{
// Signal the start of a sync-buffering scenario
HasDecoderSeeked = true;
isBuffering = true;
resumeClock = Clock.IsRunning;
Clock.Pause();
Logger.Log(MediaLogMessageType.Debug, $"SYNC-BUFFER: Started.");
// Read some frames and try to get a valid range
do
{
// Try to get more packets by waiting for read cycles.
if (CanReadMorePackets && comp.PacketBufferCount <= 0)
{
PacketReadingCycle?.WaitOne();
}
// Decode some frames and check if we are in reange now
decodedFrameCount += AddBlocks(main);
isInRange = blocks.IsInRange(wallClock);
// Break the cycle if we are in range
if (isInRange || CanReadMorePackets == false)
{
break;
}
}while (decodedFrameCount <= 0 && blocks.IsFull == false);
// Unfortunately at this point we will need to adjust the clock after creating the frames.
// to ensure tha mian component is within the clock range if the decoded
// frames are not with range. This is normal while buffering though.
if (isInRange == false)
{
// Update the wall clock to the most appropriate available block.
if (blocks.Count > 0)
{
wallClock = blocks[wallClock].StartTime;
}
else
{
resumeClock = false; // Hard stop the clock.
}
// Update the clock to what the main component range mandates
Clock.Position = wallClock;
// Call seek to invalidate renderer
Renderers[main].Seek();
}
}
else
{
// Check if we need more blocks for the current components
rangePercent = blocks.GetRangePercent(wallClock);
// Read as many blocks as we possibly can
while (comp.PacketBufferCount > 0 &&
((rangePercent > 0.75d && blocks.IsFull) || blocks.IsFull == false))
{
decodedFrameCount += AddBlocks(main);
rangePercent = blocks.GetRangePercent(wallClock);
}
}
}
#endregion
#region 3. Auxiliary Component Decoding
foreach (var t in auxs)
{
if (IsSeeking)
{
continue;
}
// Capture the current block buffer and component
// for easier readability
comp = Container.Components[t];
blocks = Blocks[t];
isInRange = blocks.IsInRange(wallClock);
// Invalidate the renderer if we don't have the block.
if (isInRange == false)
{
Renderers[t].Seek();
}
// wait for component to get there if we only have furutre blocks
// in auxiliary component.
if (blocks.Count > 0 && blocks.RangeStartTime > wallClock)
{
continue;
}
// Try to catch up with the wall clock
while (blocks.Count == 0 || blocks.RangeEndTime <= wallClock)
{
// Wait for packets if we don't have enough packets
if (CanReadMorePackets && comp.PacketBufferCount <= 0)
{
PacketReadingCycle?.WaitOne();
}
if (comp.PacketBufferCount <= 0)
{
break;
}
else
{
decodedFrameCount += AddBlocks(t);
}
}
isInRange = blocks.IsInRange(wallClock);
// Move to the next component if we don't meet a regular conditions
if (isInRange == false || isBuffering || comp.PacketBufferCount <= 0)
{
continue;
}
// Read as much as we can for this cycle.
while (comp.PacketBufferCount > 0)
{
rangePercent = blocks.GetRangePercent(wallClock);
if (blocks.IsFull == false || (blocks.IsFull && rangePercent > 0.75d && rangePercent < 1d))
{
decodedFrameCount += AddBlocks(t);
}
else
{
break;
}
}
}
#endregion
#region 4. Detect End of Media
// Detect end of block rendering
if (isBuffering == false &&
IsSeeking == false &&
CanReadMoreFramesOf(main) == false &&
Blocks[main].IndexOf(wallClock) == Blocks[main].Count - 1)
{
if (HasMediaEnded == false)
{
// Rendered all and nothing else to read
Clock.Pause();
Clock.Position = NaturalDuration.HasTimeSpan ?
NaturalDuration.TimeSpan : Blocks[main].RangeEndTime;
wallClock = Clock.Position;
HasMediaEnded = true;
MediaState = MediaState.Pause;
RaiseMediaEndedEvent();
}
}
else
{
HasMediaEnded = false;
}
#endregion
#region 6. Finish the Cycle
// complete buffering notifications
if (isBuffering)
{
// Reset the buffering flag
isBuffering = false;
// Resume the clock if it was playing
if (resumeClock)
{
Clock.Play();
}
// log some message
Logger.Log(
MediaLogMessageType.Debug,
$"SYNC-BUFFER: Finished. Clock set to {wallClock.Format()}");
}
// Complete the frame decoding cycle
FrameDecodingCycle?.Set();
// After a seek operation, always reset the has seeked flag.
HasDecoderSeeked = false;
// Give it a break if there was nothing to decode.
// We probably need to wait for some more input
if (decodedFrameCount <= 0 && Commands.PendingCount <= 0)
{
Task.Delay(1).GetAwaiter().GetResult();
}
#endregion
}
}
catch (ThreadAbortException)
{
}
finally
{
// Always exit notifying the cycle is done.
FrameDecodingCycle?.Set();
}
}
/// <summary>
/// Continually decodes the available packet buffer to have as
/// many frames as possible in each frame queue and
/// up to the MaxFrames on each component
/// </summary>
internal void RunFrameDecodingWorker()
{
try
{
// State variables
var decodedFrameCount = 0;
var wallClock = TimeSpan.Zero;
var rangePercent = 0d;
var isInRange = false;
var playAfterSeek = false;
// Holds the main media type
var main = Container.Components.Main.MediaType;
// Holds the auxiliary media types
var auxs = Container.Components.MediaTypes.ExcludeMediaType(main);
// Holds all components
var all = Container.Components.MediaTypes.DeepCopy();
var isBuffering = false;
var resumeClock = false;
var hasPendingSeeks = false;
MediaComponent comp = null;
MediaBlockBuffer blocks = null;
while (IsTaskCancellationPending == false)
{
#region 1. Setup the Decoding Cycle
// Singal a Seek starting operation
hasPendingSeeks = Commands.PendingCountOf(MediaCommandType.Seek) > 0;
if (State.IsSeeking == false && hasPendingSeeks)
{
playAfterSeek = State.IsPlaying;
State.IsSeeking = true;
SendOnSeekingStarted();
}
// Execute the following command at the beginning of the cycle
Commands.ProcessNext();
// Wait for a seek operation to complete (if any)
// and initiate a frame decoding cycle.
SeekingDone.WaitOne();
// Set initial state
wallClock = WallClock;
decodedFrameCount = 0;
// Signal a Seek ending operation
// TOD: Maybe this should go on the block rendering worker?
hasPendingSeeks = Commands.PendingCountOf(MediaCommandType.Seek) > 0;
if (State.IsSeeking && hasPendingSeeks == false)
{
// Detect a end of seek cycle and update to the final position
wallClock = SnapToFramePosition(WallClock);
Clock.Update(wallClock);
State.UpdatePosition(wallClock);
// Call the seek method on all renderers
foreach (var kvp in Renderers)
{
LastRenderTime[kvp.Key] = TimeSpan.MinValue;
kvp.Value.Seek();
}
SendOnSeekingEnded();
State.IsSeeking = false;
if (playAfterSeek)
{
Clock.Play();
State.UpdateMediaState(PlaybackStatus.Play);
}
else
{
State.UpdateMediaState(PlaybackStatus.Pause);
}
}
else if (State.IsSeeking == false)
{
// Notify position changes
State.UpdatePosition(wallClock);
}
// Initiate the frame docding cycle
FrameDecodingCycle.Reset();
#endregion
#region 2. Main Component Decoding
// Capture component and blocks for easier readability
comp = Container.Components[main];
blocks = Blocks[main];
// Handle the main component decoding; Start by checking we have some packets
while (comp.PacketBufferCount <= 0 && CanReadMorePackets)
{
PacketReadingCycle.WaitOne(Constants.Interval.LowPriority);
}
if (comp.PacketBufferCount > 0)
{
// Detect if we are in range for the main component
isInRange = blocks.IsInRange(wallClock);
if (isInRange == false)
{
// Signal the start of a sync-buffering scenario
HasDecoderSeeked = true;
isBuffering = true;
resumeClock = Clock.IsRunning;
Clock.Pause();
Log(MediaLogMessageType.Debug, $"SYNC-BUFFER: Started.");
// Read some frames and try to get a valid range
do
{
// Try to get more packets by waiting for read cycles.
if (CanReadMorePackets && comp.PacketBufferCount <= 0)
{
PacketReadingCycle.WaitOne();
}
// Decode some frames and check if we are in reange now
decodedFrameCount += AddBlocks(main);
isInRange = blocks.IsInRange(wallClock);
// Break the cycle if we are in range
if (isInRange || CanReadMorePackets == false)
{
break;
}
}while (decodedFrameCount <= 0 && blocks.IsFull == false);
// Unfortunately at this point we will need to adjust the clock after creating the frames.
// to ensure tha mian component is within the clock range if the decoded
// frames are not with range. This is normal while buffering though.
if (isInRange == false)
{
// Update the wall clock to the most appropriate available block.
if (blocks.Count > 0)
{
wallClock = blocks[wallClock].StartTime;
}
else
{
resumeClock = false; // Hard stop the clock.
}
// Update the clock to what the main component range mandates
Clock.Update(wallClock);
// Call seek to invalidate renderer
LastRenderTime[main] = TimeSpan.MinValue;
Renderers[main].Seek();
// Try to recover the regular loop
isInRange = true;
while (CanReadMorePackets && comp.PacketBufferCount <= 0)
{
PacketReadingCycle.WaitOne();
}
}
}
if (isInRange)
{
// Check if we need more blocks for the current components
rangePercent = blocks.GetRangePercent(wallClock);
// Read as much as we can for this cycle.
while (comp.PacketBufferCount > 0)
{
rangePercent = blocks.GetRangePercent(wallClock);
if (blocks.IsFull == false || (blocks.IsFull && rangePercent > 0.75d && rangePercent < 1d))
{
decodedFrameCount += AddBlocks(main);
}
else
{
break;
}
}
}
}
#endregion
#region 3. Auxiliary Component Decoding
foreach (var t in auxs)
{
if (State.IsSeeking)
{
continue;
}
// Capture the current block buffer and component
// for easier readability
comp = Container.Components[t];
blocks = Blocks[t];
isInRange = blocks.IsInRange(wallClock);
// Invalidate the renderer if we don't have the block.
if (isInRange == false)
{
LastRenderTime[t] = TimeSpan.MinValue;
Renderers[t].Seek();
}
// wait for component to get there if we only have furutre blocks
// in auxiliary component.
if (blocks.Count > 0 && blocks.RangeStartTime > wallClock)
{
continue;
}
// Try to catch up with the wall clock
while (blocks.Count == 0 || blocks.RangeEndTime <= wallClock)
{
// Wait for packets if we don't have enough packets
if (CanReadMorePackets && comp.PacketBufferCount <= 0)
{
PacketReadingCycle.WaitOne();
}
if (comp.PacketBufferCount <= 0)
{
break;
}
else
{
decodedFrameCount += AddBlocks(t);
}
}
isInRange = blocks.IsInRange(wallClock);
// Move to the next component if we don't meet a regular conditions
if (isInRange == false || isBuffering || comp.PacketBufferCount <= 0)
{
continue;
}
// Read as much as we can for this cycle.
while (comp.PacketBufferCount > 0)
{
rangePercent = blocks.GetRangePercent(wallClock);
if (blocks.IsFull == false || (blocks.IsFull && rangePercent > 0.75d && rangePercent < 1d))
{
decodedFrameCount += AddBlocks(t);
}
else
{
break;
}
}
}
#endregion
#region 4. Detect End of Media
// Detect end of block rendering
// TODO: Maybe this detection should be performed on the BlockRendering worker?
if (isBuffering == false &&
State.IsSeeking == false &&
CanReadMoreFramesOf(main) == false &&
Blocks[main].IndexOf(wallClock) == Blocks[main].Count - 1)
{
if (State.HasMediaEnded == false)
{
// Rendered all and nothing else to read
Clock.Pause();
if (State.NaturalDuration != null && State.NaturalDuration != TimeSpan.MinValue)
{
wallClock = State.NaturalDuration.Value;
}
else
{
wallClock = Blocks[main].RangeEndTime;
}
Clock.Update(wallClock);
State.HasMediaEnded = true;
State.UpdateMediaState(PlaybackStatus.Pause, wallClock);
SendOnMediaEnded();
}
}
else
{
State.HasMediaEnded = false;
}
#endregion
#region 6. Finish the Cycle
// complete buffering notifications
if (isBuffering)
{
// Reset the buffering flag
isBuffering = false;
// Resume the clock if it was playing
if (resumeClock)
{
Clock.Play();
}
// log some message
Log(
MediaLogMessageType.Debug,
$"SYNC-BUFFER: Finished. Clock set to {wallClock.Format()}");
}
// Complete the frame decoding cycle
FrameDecodingCycle.Set();
// After a seek operation, always reset the has seeked flag.
HasDecoderSeeked = false;
// If not already set, guess the 1-second buffer length
State.GuessBufferingProperties();
// Give it a break if there was nothing to decode.
// We probably need to wait for some more input
if (decodedFrameCount <= 0 && Commands.PendingCount <= 0)
{
Task.Delay(1).GetAwaiter().GetResult();
}
#endregion
}
}
catch (ThreadAbortException) { /* swallow */ }
catch { if (!IsDisposed)
{
throw;
}
}
finally
{
// Always exit notifying the cycle is done.
FrameDecodingCycle.Set();
}
}
