/// <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)
{
m_Pointer = (AVSubtitle *)InternalPointer;
// Extract timing information (pts for Subtitles is always in AV_TIME_BASE units)
HasValidStartTime = frame->pts != FFmpegEx.AV_NOPTS;
var timeOffset = TimeSpan.FromTicks(frame->pts.ToTimeSpan(ffmpeg.AV_TIME_BASE).Ticks - component.Container.MediaStartTimeOffset.Ticks);
StartTime = TimeSpan.FromTicks(timeOffset.Ticks + ((long)frame->start_display_time).ToTimeSpan(StreamTimeBase).Ticks);
EndTime = TimeSpan.FromTicks(timeOffset.Ticks + ((long)frame->end_display_time).ToTimeSpan(StreamTimeBase).Ticks);
Duration = TimeSpan.FromTicks(EndTime.Ticks - StartTime.Ticks);
// 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)
{
Text.Add(Utils.PtrToStringUTF8(rect->text));
TextType = AVSubtitleType.SUBTITLE_TEXT;
break;
}
}
else if (rect->type == AVSubtitleType.SUBTITLE_ASS)
{
if (rect->ass != null)
{
Text.Add(Utils.PtrToStringUTF8(rect->ass));
TextType = AVSubtitleType.SUBTITLE_ASS;
break;
}
}
else
{
TextType = rect->type;
}
}
}
/// <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)
{
m_Pointer = (AVFrame *)InternalPointer;
// Compute the timespans.
// We don't use for Audio frames: frame->pts = ffmpeg.av_frame_get_best_effort_timestamp(frame);
HasValidStartTime = frame->pts != FFmpegEx.AV_NOPTS;
StartTime = frame->pts == FFmpegEx.AV_NOPTS ?
TimeSpan.FromTicks(component.Container.MediaStartTimeOffset.Ticks) :
TimeSpan.FromTicks(frame->pts.ToTimeSpan(StreamTimeBase).Ticks - component.Container.MediaStartTimeOffset.Ticks);
// Compute the audio frame duration
if (frame->pkt_duration != 0)
{
Duration = frame->pkt_duration.ToTimeSpan(StreamTimeBase);
}
else
{
Duration = TimeSpan.FromTicks((long)Math.Round(TimeSpan.TicksPerMillisecond * 1000d * frame->nb_samples / frame->sample_rate, 0));
}
EndTime = TimeSpan.FromTicks(StartTime.Ticks + Duration.Ticks);
}
/// <summary>
/// Initializes a new instance of the <see cref="VideoFrame" /> class.
/// </summary>
/// <param name="frame">The frame.</param>
/// <param name="component">The component.</param>
internal VideoFrame(AVFrame *frame, MediaComponent component)
: base(frame, component)
{
const int AV_TIMECODE_STR_SIZE = 16 + 1;
m_Pointer = (AVFrame *)InternalPointer;
var repeatFactor = 1d + (0.5d * frame->repeat_pict);
var timeBase = ffmpeg.av_guess_frame_rate(component.Container.InputContext, component.Stream, frame);
Duration = repeatFactor.ToTimeSpan(new AVRational {
num = timeBase.den, den = timeBase.num
});
// for video frames, we always get the best effort timestamp as dts and pts might
// contain different times.
frame->pts = ffmpeg.av_frame_get_best_effort_timestamp(frame);
HasValidStartTime = frame->pts != FFmpegEx.AV_NOPTS;
StartTime = frame->pts == FFmpegEx.AV_NOPTS ?
TimeSpan.FromTicks(component.Container.MediaStartTimeOffset.Ticks) :
TimeSpan.FromTicks(frame->pts.ToTimeSpan(StreamTimeBase).Ticks - component.Container.MediaStartTimeOffset.Ticks);
EndTime = TimeSpan.FromTicks(StartTime.Ticks + Duration.Ticks);
DisplayPictureNumber = frame->display_picture_number == 0 ?
(int)Math.Round((double)StartTime.Ticks / Duration.Ticks, 0) : 0;
CodedPictureNumber = frame->coded_picture_number;
// SMTPE timecode calculation
var timeCodeInfo = (AVTimecode *)ffmpeg.av_malloc((ulong)Marshal.SizeOf(typeof(AVTimecode)));
var startFrameNumber = (int)Math.Round((double)component.StartTimeOffset.Ticks / Duration.Ticks, 0);
ffmpeg.av_timecode_init(timeCodeInfo, timeBase, 0, startFrameNumber, null);
var isNtsc = timeBase.num == 30000 && timeBase.den == 1001;
var frameNumber = isNtsc ?
ffmpeg.av_timecode_adjust_ntsc_framenum2(DisplayPictureNumber, (int)timeCodeInfo->fps) :
DisplayPictureNumber;
var timeCode = ffmpeg.av_timecode_get_smpte_from_framenum(timeCodeInfo, DisplayPictureNumber);
var timeCodeBuffer = (byte *)ffmpeg.av_malloc(AV_TIMECODE_STR_SIZE);
ffmpeg.av_timecode_make_smpte_tc_string(timeCodeBuffer, timeCode, 1);
SmtpeTimecode = Marshal.PtrToStringAnsi(new IntPtr(timeCodeBuffer));
ffmpeg.av_free(timeCodeInfo);
ffmpeg.av_free(timeCodeBuffer);
// Process side data such as CC packets
for (var i = 0; i < frame->nb_side_data; i++)
{
var sideData = frame->side_data[i];
// Get the Closed-Caption packets
if (sideData->type == AVFrameSideDataType.AV_FRAME_DATA_A53_CC)
{
// Parse 3 bytes at a time
for (var p = 0; p < sideData->size; p += 3)
{
var packet = new ClosedCaptionPacket(StartTime, sideData->data[p + 0], sideData->data[p + 1], sideData->data[p + 2]);
if (packet.PacketType == CCPacketType.NullPad || packet.PacketType == CCPacketType.Unrecognized)
{
continue;
}
// at this point, we have valid CC data
ClosedCaptions.Add(packet);
}
continue;
}
}
}
#pragma warning restore SA1401 // Fields must be private
#endregion
#region Constructor
/// <summary>
/// Initializes a new instance of the <see cref="MediaFrame" /> class.
/// </summary>
/// <param name="pointer">The pointer.</param>
/// <param name="component">The component.</param>
internal MediaFrame(void *pointer, MediaComponent component)
{
InternalPointer = pointer;
StreamTimeBase = component.Stream->time_base;
StreamIndex = component.StreamIndex;
}
