gecko-dev/netwerk/dash/mpd/IMPDManager.h

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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts =2 et sw =2 tw =80: */
/*
* IMPDManager.h
*****************************************************************************
* Copyrigh(C) 2010 - 2011 Klagenfurt University
*
* Created on: Aug 10, 2010
* Authors: Christopher Mueller <christopher.mueller@itec.uni-klu.ac.at>
* Christian Timmerer <christian.timmerer@itec.uni-klu.ac.at>
* Contributors:
* Steve Workman <sworkman@mozilla.com>
*
* This Source Code Form Is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/.
*****************************************************************************/
/* DASH - Dynamic Adaptive Streaming over HTTP.
*
* DASH is an adaptive bitrate streaming technology where a multimedia file is
* partitioned into one or more segments and delivered to a client using HTTP.
*
* (see DASHDecoder.cpp for info on DASH interaction with the media engine).
*
* Media Presentation Description (MPD) Manager.
*
* Interface to MPD classes, populated with data from MPD XML manifest.
* Employs adaptation algorithm to determine best representation of media to
* download.
* Adaptation algorithm is separate and passed into manager.
* Interface aims to be an abstracted API for all DASH MPD Profiles
* (e.g. DASH WebM On Demand Profile).
*/
#ifndef IMPDMANAGER_H_
#define IMPDMANAGER_H_
#include "nsTArray.h"
#include "nsIURI.h"
#include "nsIDOMElement.h"
namespace mozilla {
namespace net {
// DASH MPD Profile Type
enum DASHMPDProfile
{
WebMOnDemand,
NotValid
// Extend this for other types.
};
class Period;
class Representation;
class Segment;
class IMPDManager
{
public:
// Describes the media type (audio/video) of the |AdaptationSet|.
enum AdaptationSetType {
DASH_ASTYPE_INVALID = 0,
DASH_VIDEO_STREAM,
DASH_AUDIO_STREAM,
DAHS_AUDIO_VIDEO_STREAM
};
IMPDManager()
{
MOZ_COUNT_CTOR(IMPDManager);
}
virtual ~IMPDManager()
{
MOZ_COUNT_DTOR(IMPDManager);
}
// Used to get the first |Period| in the presentation.
virtual Period const * GetFirstPeriod() const = 0;
// Gets the total number of |AdaptationSet|s in the first |Period|.
// Usually, this should be 2 for audio and video.
// XXX Future versions may require a |Period| index.
// XXX Future versions may have multiple tracks for audio.
virtual uint32_t GetNumAdaptationSets() const = 0;
// Returns the media type for the given |AdaptationSet|, audio/video.
virtual AdaptationSetType
GetAdaptationSetType(uint32_t const aAdaptSetIdx) const = 0;
// Gets the number of media |Representation|s for the given |AdaptationSet|.
// e.g how many bitrate encodings are there of the audio stream?
virtual uint32_t
GetNumRepresentations(uint32_t const aAdaptSetIdx) const = 0;
// Gets the specified |Representation| from the specified |AdaptationSet|,
// e.g. get metadata about the 64Kbps encoding of the video stream.
virtual Representation const *
GetRepresentation(uint32_t const aAdaptSetIdx,
uint32_t const aRepIdx) const = 0;
// Gets the URL of the first media |Segment| for the specific media
// |Representation|, e.g. the url of the first 64Kbps video segment.
virtual nsresult GetFirstSegmentUrl(uint32_t const aAdaptSetIdx,
uint32_t const aRepIdx,
nsAString &aUrl) const = 0;
// Returns the start time of the presentation in seconds.
virtual double GetStartTime() const = 0;
// Returns the duration of the presentation in seconds.
virtual double GetDuration() const = 0;
// Gets index of the |Representation| with next highest bitrate to the
// estimated bandwidth passed in. Returns true if there is at least one
// |Representation| with a bitrate lower than |aBandwidth|; otherwise returns
// false. Depends on |mRepresentations| being an ordered list.
virtual bool GetBestRepForBandwidth(uint32_t aAdaptSetIdx,
uint64_t aBandwidth,
uint32_t &aRepIdx) const = 0;
public:
// Factory method.
static IMPDManager* Create(DASHMPDProfile Profile, nsIDOMElement* aRoot);
private:
// Used by factory method.
static IMPDManager* CreateWebMOnDemandManager(nsIDOMElement* aRoot);
};
}//namespace net
}//namespace mozilla
#endif /* IMPDMANAGER_H_ */