jellyfin/MediaBrowser.Api/Playback/Dash/ManifestBuilder.cs
2015-03-16 10:40:44 -04:00

225 lines
7.8 KiB
C#

using System;
using System.Globalization;
using System.Security;
using System.Text;
namespace MediaBrowser.Api.Playback.Dash
{
public class ManifestBuilder
{
protected readonly CultureInfo UsCulture = new CultureInfo("en-US");
public string GetManifestText(StreamState state, string playlistUrl)
{
var builder = new StringBuilder();
var time = TimeSpan.FromTicks(state.RunTimeTicks.Value);
var duration = "PT" + time.Hours.ToString("00", UsCulture) + "H" + time.Minutes.ToString("00", UsCulture) + "M" + time.Seconds.ToString("00", UsCulture) + ".00S";
builder.Append("<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
builder.AppendFormat(
"<MPD xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns=\"urn:mpeg:dash:schema:mpd:2011\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" xsi:schemaLocation=\"urn:mpeg:DASH:schema:MPD:2011 http://standards.iso.org/ittf/PubliclyAvailableStandards/MPEG-DASH_schema_files/DASH-MPD.xsd\" profiles=\"urn:mpeg:dash:profile:isoff-live:2011\" type=\"static\" mediaPresentationDuration=\"{0}\" minBufferTime=\"PT5.0S\">",
duration);
builder.Append("<ProgramInformation>");
builder.Append("</ProgramInformation>");
builder.Append("<Period start=\"PT0S\">");
builder.Append(GetVideoAdaptationSet(state, playlistUrl));
builder.Append(GetAudioAdaptationSet(state, playlistUrl));
builder.Append("</Period>");
builder.Append("</MPD>");
return builder.ToString();
}
private string GetVideoAdaptationSet(StreamState state, string playlistUrl)
{
var builder = new StringBuilder();
builder.Append("<AdaptationSet id=\"video\" segmentAlignment=\"true\" bitstreamSwitching=\"true\">");
builder.Append(GetVideoRepresentationOpenElement(state));
AppendSegmentList(state, builder, "0", playlistUrl);
builder.Append("</Representation>");
builder.Append("</AdaptationSet>");
return builder.ToString();
}
private string GetAudioAdaptationSet(StreamState state, string playlistUrl)
{
var builder = new StringBuilder();
builder.Append("<AdaptationSet id=\"audio\" segmentAlignment=\"true\" bitstreamSwitching=\"true\">");
builder.Append(GetAudioRepresentationOpenElement(state));
builder.Append("<AudioChannelConfiguration schemeIdUri=\"urn:mpeg:dash:23003:3:audio_channel_configuration:2011\" value=\"6\" />");
AppendSegmentList(state, builder, "1", playlistUrl);
builder.Append("</Representation>");
builder.Append("</AdaptationSet>");
return builder.ToString();
}
private string GetVideoRepresentationOpenElement(StreamState state)
{
var codecs = GetVideoCodecDescriptor(state);
var mime = "video/mp4";
var xml = "<Representation id=\"0\" mimeType=\"" + mime + "\" codecs=\"" + codecs + "\"";
if (state.OutputWidth.HasValue)
{
xml += " width=\"" + state.OutputWidth.Value.ToString(UsCulture) + "\"";
}
if (state.OutputHeight.HasValue)
{
xml += " height=\"" + state.OutputHeight.Value.ToString(UsCulture) + "\"";
}
if (state.OutputVideoBitrate.HasValue)
{
xml += " bandwidth=\"" + state.OutputVideoBitrate.Value.ToString(UsCulture) + "\"";
}
xml += ">";
return xml;
}
private string GetAudioRepresentationOpenElement(StreamState state)
{
var codecs = GetAudioCodecDescriptor(state);
var mime = "audio/mp4";
var xml = "<Representation id=\"1\" mimeType=\"" + mime + "\" codecs=\"" + codecs + "\"";
if (state.OutputAudioSampleRate.HasValue)
{
xml += " audioSamplingRate=\"" + state.OutputAudioSampleRate.Value.ToString(UsCulture) + "\"";
}
if (state.OutputAudioBitrate.HasValue)
{
xml += " bandwidth=\"" + state.OutputAudioBitrate.Value.ToString(UsCulture) + "\"";
}
xml += ">";
return xml;
}
private string GetVideoCodecDescriptor(StreamState state)
{
// https://developer.apple.com/library/ios/documentation/networkinginternet/conceptual/streamingmediaguide/FrequentlyAskedQuestions/FrequentlyAskedQuestions.html
// http://www.chipwreck.de/blog/2010/02/25/html-5-video-tag-and-attributes/
var level = state.TargetVideoLevel ?? 0;
var profile = state.TargetVideoProfile ?? string.Empty;
if (profile.IndexOf("high", StringComparison.OrdinalIgnoreCase) != -1)
{
if (level >= 4.1)
{
return "avc1.640028";
}
if (level >= 4)
{
return "avc1.640028";
}
return "avc1.64001f";
}
if (profile.IndexOf("main", StringComparison.OrdinalIgnoreCase) != -1)
{
if (level >= 4)
{
return "avc1.4d0028";
}
if (level >= 3.1)
{
return "avc1.4d001f";
}
return "avc1.4d001e";
}
if (level >= 3.1)
{
return "avc1.42001f";
}
return "avc1.42E01E";
}
private string GetAudioCodecDescriptor(StreamState state)
{
// https://developer.apple.com/library/ios/documentation/networkinginternet/conceptual/streamingmediaguide/FrequentlyAskedQuestions/FrequentlyAskedQuestions.html
if (string.Equals(state.OutputAudioCodec, "mp3", StringComparison.OrdinalIgnoreCase))
{
return "mp4a.40.34";
}
// AAC 5ch
if (state.OutputAudioChannels.HasValue && state.OutputAudioChannels.Value >= 5)
{
return "mp4a.40.5";
}
// AAC 2ch
return "mp4a.40.2";
}
private void AppendSegmentList(StreamState state, StringBuilder builder, string type, string playlistUrl)
{
var extension = ".m4s";
var seconds = TimeSpan.FromTicks(state.RunTimeTicks ?? 0).TotalSeconds;
var queryStringIndex = playlistUrl.IndexOf('?');
var queryString = queryStringIndex == -1 ? string.Empty : playlistUrl.Substring(queryStringIndex);
var index = 0;
var duration = 1000000 * state.SegmentLength;
builder.AppendFormat("<SegmentList timescale=\"1000000\" duration=\"{0}\" startNumber=\"1\">", duration.ToString(CultureInfo.InvariantCulture));
while (seconds > 0)
{
var filename = index == 0
? "init"
: (index - 1).ToString(UsCulture);
var segmentUrl = string.Format("dash/{3}/{0}{1}{2}",
filename,
extension,
SecurityElement.Escape(queryString),
type);
if (index == 0)
{
builder.AppendFormat("<Initialization sourceURL=\"{0}\"/>", segmentUrl);
}
else
{
builder.AppendFormat("<SegmentURL media=\"{0}\"/>", segmentUrl);
}
seconds -= state.SegmentLength;
index++;
}
builder.Append("</SegmentList>");
}
}
}