/// <summary>
/// Initializes a new instance of the <see cref="MediaFrame" /> class.
/// </summary>
/// <param name="pointer">The pointer.</param>
/// <param name="component">The component.</param>
/// <param name="mediaType">Type of the media.</param>
private MediaFrame(void *pointer, MediaComponent component, MediaType mediaType)
{
InternalPointer = new IntPtr(pointer);
StreamTimeBase = component.Stream->time_base;
StreamIndex = component.StreamIndex;
MediaType = mediaType;
}
/// <summary>
/// Initializes a new instance of the <see cref="MediaFrame"/> class.
/// </summary>
/// <param name="pointer">The pointer.</param>
/// <param name="component">The component.</param>
protected MediaFrame(AVSubtitle *pointer, MediaComponent component)
: this(pointer, component, MediaType.Subtitle)
{
// TODO: Compressed size is simply an estimate
CompressedSize = (int)pointer->num_rects * 256;
PresentationTime = Convert.ToInt64(pointer->start_display_time);
DecodingTime = pointer->pts;
}
/// <summary>
/// Initializes a new instance of the <see cref="MediaFrame" /> class.
/// </summary>
/// <param name="pointer">The pointer.</param>
/// <param name="component">The component.</param>
/// <param name="mediaType">Type of the media.</param>
protected MediaFrame(AVFrame *pointer, MediaComponent component, MediaType mediaType)
: this((void *)pointer, component, mediaType)
{
var packetSize = pointer->pkt_size;
CompressedSize = packetSize > 0 ? packetSize : 0;
PresentationTime = pointer->pts;
DecodingTime = pointer->pkt_dts;
}
internal void AddComponent(MediaComponent component)
{
lock (ComponentSyncLock)
{
if (component == null)
{
throw new ArgumentNullException(nameof(component));
}
var errorMessage = $"A component for '{component.MediaType}' is already registered.";
switch (component.MediaType)
{
case MediaType.Audio:
if (m_Audio != null)
{
throw new ArgumentException(errorMessage);
}
m_Audio = component as AudioComponent;
break;
case MediaType.Video:
if (m_Video != null)
{
throw new ArgumentException(errorMessage);
}
m_Video = component as VideoComponent;
break;
case MediaType.Subtitle:
if (m_Subtitle != null)
{
throw new ArgumentException(errorMessage);
}
m_Subtitle = component as SubtitleComponent;
break;
default:
throw new NotSupportedException($"Unable to register component with {nameof(MediaType)} '{component.MediaType}'");
}
UpdateComponentBackingFields();
}
}
/// <summary>
/// Initializes a new instance of the <see cref="AudioFrame" /> class.
/// </summary>
/// <param name="frame">The frame.</param>
/// <param name="component">The component.</param>
internal AudioFrame(AVFrame *frame, MediaComponent component)
: base(frame, component, MediaType.Audio)
{
// Compute the start time.
frame->pts = frame->best_effort_timestamp;
HasValidStartTime = frame->pts != ffmpeg.AV_NOPTS_VALUE;
StartTime = frame->pts == ffmpeg.AV_NOPTS_VALUE ?
TimeSpan.FromTicks(0) :
TimeSpan.FromTicks(frame->pts.ToTimeSpan(StreamTimeBase).Ticks);
// Compute the audio frame duration
Duration = frame->pkt_duration > 0 ?
frame->pkt_duration.ToTimeSpan(StreamTimeBase) :
TimeSpan.FromTicks(Convert.ToInt64(TimeSpan.TicksPerMillisecond * 1000d * frame->nb_samples / frame->sample_rate));
// Compute the audio frame end time
EndTime = TimeSpan.FromTicks(StartTime.Ticks + Duration.Ticks);
}
/// <summary>
/// Initializes a new instance of the <see cref="SubtitleFrame" /> class.
/// </summary>
/// <param name="frame">The frame.</param>
/// <param name="component">The component.</param>
internal SubtitleFrame(AVSubtitle *frame, MediaComponent component)
: base(frame, component)
{
// Extract timing information (pts for Subtitles is always in AV_TIME_BASE units)
HasValidStartTime = frame->pts != ffmpeg.AV_NOPTS_VALUE;
var timeOffset = frame->pts.ToTimeSpan(ffmpeg.AV_TIME_BASE);
// start_display_time and end_display_time are relative to timeOffset
StartTime = TimeSpan.FromMilliseconds(timeOffset.TotalMilliseconds + frame->start_display_time);
EndTime = TimeSpan.FromMilliseconds(timeOffset.TotalMilliseconds + frame->end_display_time);
Duration = TimeSpan.FromMilliseconds(frame->end_display_time - frame->start_display_time);
// Extract text strings
TextType = AVSubtitleType.SUBTITLE_NONE;
for (var i = 0; i < frame->num_rects; i++)
{
var rect = frame->rects[i];
if (rect->type == AVSubtitleType.SUBTITLE_TEXT)
{
if (rect->text == null)
{
continue;
}
Text.Add(Utilities.PtrToStringUTF8(rect->text));
TextType = AVSubtitleType.SUBTITLE_TEXT;
break;
}
if (rect->type == AVSubtitleType.SUBTITLE_ASS)
{
if (rect->ass == null)
{
continue;
}
Text.Add(Utilities.PtrToStringUTF8(rect->ass));
TextType = AVSubtitleType.SUBTITLE_ASS;
break;
}
TextType = rect->type;
}
}
private unsafe void UpdateComponentBackingFields()
{
var allComponents = new List <MediaComponent>(4);
var allMediaTypes = new List <MediaType>(4);
// assign allMediaTypes. IMPORTANT: Order matters because this
// establishes the priority in which playback measures are computed
if (m_Video != null)
{
allComponents.Add(m_Video);
allMediaTypes.Add(MediaType.Video);
}
if (m_Audio != null)
{
allComponents.Add(m_Audio);
allMediaTypes.Add(MediaType.Audio);
}
if (m_Subtitle != null)
{
allComponents.Add(m_Subtitle);
allMediaTypes.Add(MediaType.Subtitle);
}
m_All = allComponents;
m_MediaTypes = allMediaTypes;
m_Count = allComponents.Count;
// Find Start time, duration and end time
UpdatePlaybackTimingProperties();
// Try for the main component to be the video (if it's not stuff like audio album art, that is)
if (m_Video != null && m_Audio != null && m_Video.StreamInfo.IsAttachedPictureDisposition == false)
{
m_Main = m_Video;
m_MainMediaType = MediaType.Video;
return;
}
// If it was not video, then it has to be audio (if it has audio)
if (m_Audio != null)
{
m_Main = m_Audio;
m_MainMediaType = MediaType.Audio;
return;
}
// Set it to video even if it's attached pic stuff
if (m_Video != null)
{
m_Main = m_Video;
m_MainMediaType = MediaType.Video;
return;
}
// As a last resort, set the main component to be the subtitles
if (m_Subtitle != null)
{
m_Main = m_Subtitle;
m_MainMediaType = MediaType.Subtitle;
return;
}
// We should never really hit this line
m_Main = null;
m_MainMediaType = MediaType.None;
}
