Playback Using AVPlay
This topic describes how your application can play media content using the AVPlay API.
Related Info
In general, common media formats can be played using the HTML5 <video>
and <audio>
elements. To play media content with features not supported in HTML5, such as adaptive streaming, additional subtitle formats, and 4K UHD video, use the Samsung Product AVPlay API.
For information on the supported media containers, streaming format and DRM combinations, and network protocols, see the General Specifications.
AVPlay Life-cycle
An AVPlay
instance has various states, which determine the actions you can take. You must also pay attention to the state limitations for the AVPlay API methods.
The following table lists the possible AVPlay
instance states.
State | Description |
---|---|
NONE | Before the instance is created, or after it is removed with the close() method.
|
IDLE | After the instance is created by opening the media with the open() method.
|
READY | During and after media buffering. In this state you can, for example, use the getDuration() method to retrieve the duration of the media.
|
PLAYING | When playback is in progress. In this state you can, for example, use the getCurrentTime() method to retrieve the current time of the media.
|
PAUSED | When playback is paused with the pause() method.
|
Table 1. AVPlay instance states
The following figure shows the state changes and life-cycle of an AVPlay
instance, and the playback control operations that drive state transitions.
Prerequisites
To enable your application to use the functionalities of the AVPlay API:
-
To use the AVPlay API, include the WebAPI library in the “index.html” file:
<head> ... <script type="text/javascript" src="$WEBAPIS/webapis/webapis.js"></script> ... </head>
-
To access external network resources through the application, set the appropriate content security policy (CSP) in the “config.xml” file.
ImportantSince 2015 models, thehttp://developer.samsung.com/privilege/avplay
privilege is not used in TV Web applications.
Playing Media
To play media using the AVPlay API:
-
Create an element for media playback, using an
object
element with the "application/avplayer"type
attribute:var objElem = document.createElement('object'); objElem.type = 'application/avplayer'; /* //Adjust the size and position of the media display area //by changing the CSS style attribute objElem.style.left = 100 + 'px'; objElem.style.top = 200 + 'px'; objElem.style.width = 600 + 'px'; objElem.style.height = 400 + 'px'; */ //Append the object element to your document document.body.appendChild(objElem);
-
Open a media file using the
open()
method.
The AVPlay API supports absolute local paths and remote network URIs. Relative local paths are not supported.webapis.avplay.open('yourMediaURI');
After the media file is successfully opened, the
AVPlay
instance is created in the IDLE state. -
Define the event handlers using the
setListener()
method. The following table lists the available event handlers.Event Handler Description onbufferingstart()
Media data buffering has started. onbufferingprogress()
Media data buffering progress percentage. onbufferingcomplete()
Media data buffering has completed. onstreamcompleted()
Media playback has completed. oncurrentplaytime()
Current playback time in the PLAYING state, in milliseconds. onerror()
An error has occurred during media playback. onevent()
Some other event is received by the player. onsubtitlechange()
Subtitle text has changed. ondrmevent()
DRM information is detected by the player. Table 2. Event methods
var listener = { onbufferingstart: function() { console.log("Buffering start."); }, onbufferingprogress: function(percent) { console.log("Buffering progress data : " + percent); }, onbufferingcomplete: function() { console.log("Buffering complete."); }, onstreamcompleted: function() { console.log("Stream Completed"); webapis.avplay.stop(); }, oncurrentplaytime: function(currentTime) { console.log("Current playtime: " + currentTime); }, onerror: function(eventType) { console.log("event type error : " + eventType); }, onevent: function(eventType, eventData) { console.log("event type: " + eventType + ", data: " + eventData); }, onsubtitlechange: function(duration, text, data3, data4) { console.log("subtitleText: " + text); }, ondrmevent: function(drmEvent, drmData) { console.log("DRM callback: " + drmEvent + ", data: " + drmData); } }; webapis.avplay.setListener(listener);
-
For video media, set the media display area using the
setDisplayRect()
method.
ThesetDisplayRect()
method takes 4 parameters: the position from the left side of the screen, the position from the top of the screen, the width, and the height. For the purpose of thesetDisplayRect()
method parameters, the TV screen resolution is always treated as 1920x1080 px, regardless of the application resolution or viewport size.
If the application resolution is 1920x1080 px, simply set the same position values as defined in theobject
elementstyle
attribute. Otherwise, you must calculate the values for thesetDisplayRect()
method parameters.// For example, video positon is // left: 100 px / top: 200 px / width: 600 px / height: 400 px // Case 1: Application resolution 1920x1080 px webapis.avplay.setDisplayRect(100,200,600,400); // Case 2: Other application resolution // Base resolution of avplay var avplayBaseWidth = 1920; // Calculate ratio to base resolution var ratio = avplayBaseWidth / window.document.documentElement.clientWidth; // Convert rectangle to base resolution var newLeft = 100 * ratio; var newTop = 200 * ratio; var newWidth = 600 * ratio; var newHeight = 400 * ratio; webapis.avplay.setDisplayRect(newLeft,newTop,newWidth,newHeight);
NoteIf you use thesetDisplayRect()
method to change the media display area size or position during media playback, theobject
elementstyle
attribute must also be changed correspondingly.By default, video is displayed full screen within the media display area. To fit the video to the media display area:
webapis.avplay.setDisplayMethod('PLAYER_DISPLAY_MODE_LETTER_BOX')
-
Prepare the media for playback, synchronously or asynchronously:
- To prepare the media synchronously, use the
prepare()
method.
Because preparation can involve fetching and decoding media data, theprepare()
method can take a long time to execute. Do not call it from your application’s UI thread, as it causes the UI to hang until execution is finished.webapis.avplay.prepare();
- To prepare the media asynchronously, use the
prepareAsync()
method.
This method starts preparing in the background and returns immediately. When the media is finished preparing, thesuccessCallback()
method is invoked.var successCallback = function() { console.log('The media has finished preparing'); } var errorCallback = function() { console.log('The media has failed to prepare'); } webapis.avplay.prepareAsync(successCallback,errorCallback);
When the
AVPlay
instance starts preparing the media, theonbufferingstart()
event handler is invoked, and theAVPlay
instance enters the READY state. - To prepare the media synchronously, use the
-
To manage starting and stopping playback:
-
Start playback using the
play()
method:webapis.avplay.play();
When playback starts, the
oncurrentplaytime()
event handler is invoked, and theAVPlay
instance enters the PLAYING state. -
Pause playback using the
pause()
method:webapis.avplay.pause();
The
AVPlay
instance enters the PAUSED state. Playback can be resumed using theplay()
method. -
When playback is complete, stop the player:
webapis.avplay.stop();
The
AVPlay
instance enters the IDLE state. The instance retains its configuration, such as the media URI, display area, and event methods. To replay the media, you can simply call theprepare()
andplay()
methods again.NoteFailure to stop playback after the media has finished playing causes the media player window to show the final frame continuously.
-
-
To remove the
AVPlay
instance, call theclose()
method.
Managing Media Playback
Using the AVPlay API, you can implement functionalities such as jumping to a specific time in the media, adjusting the playback rate, and switching audio tracks.
Media Seek
You can jump to a specific time in the media based on an absolute time or relative time:
-
To jump based on an absolute time, use the
seekTo()
method:- Retrieve the current playback time using the
getCurrentTime()
method. - Set the time to jump to. The new time must be a positive value, which is less than the duration of the media.
//Media seek during playback var successCallback = function() { console.log('Media seek successful'); } var errorCallback = function() { console.log('Media seek failed'); } //Jump forward by 5000 ms var currentTime = webapis.avplay.getCurrentTime(); var newTime = currentTime + 5000; webapis.avplay.seekTo(newTime,successCallback,errorCallback);
You can also set the start position for media playback by calling the
seekTo()
method when theAVPlay
instance is in the IDLE state.//Change playback start time var successCallback = function() { console.log('Media seek successful'); } var errorCallback = function() { console.log('Media seek failed'); } webapis.avplay.open('yourMediaURI'); ... //Move the playback start time to 10 minutes webapis.avplay.seekTo(600000,successCallback,errorCallback); ... webapis.avplay.prepare();
- Retrieve the current playback time using the
-
To jump based on a relative time, use the
jumpForward()
andjumpBackward()
methods://Media seek during playback var successCallback = function() { console.log('Media seek successful'); } var errorCallback = function() { console.log('Media seek failed'); } //Case 1 Fast-forward by 5000 ms webapis.avplay.jumpFoward(5000,successCallback,errorCallback); //Case 2 Rewind by 5000 ms webapis.avplay.jumpBackward(5000,successCallback,errorCallback);
NoteYou must check that the value of the parameter is within the valid range, based on the current playback time.
Playback Rate Control (Trick Play)
You can control the playback rate of the media using the setSpeed()
method to set a multiplier for the playback rate. Positive parameter values play the media forwards, while negative values cause the media to play in reverse.
For example, to play the media at double speed:
webapis.avplay.setSpeed(2);
The maximum playback rate depends on the streaming format.
Streaming Format | Playback Rate Range |
---|---|
Smooth Streaming | -16x ~ +16x |
HTTP(S) | -8x ~ +8x |
MPEG-DASH | -16x ~ +16x |
HTTP Live Streaming (HLS) | Since 2017 models: -16x ~ +16x for content with EXT-X-I-FRAME-STREAM_INF tag only
|
Table 3. Playback rates for streaming formats
Audio Track Switching
To switch between multiple audio tracks during media playback:
-
Retrieve the audio track list.
ThegetTotalTrackInfo()
method of the AVPlay API can only be called when theAVPlay
instance is in the READY, PLAYING, or PAUSED states. It returns an array of objects for all tracks in the media.
Each object has 3 properties:type
: TheAUDIO
value identifies the track as an audio track.index
: The index number for the track.extra_info
: Additional information about the track, such as language information and number of channels.
var totalTrackInfo = webapis.avplay.getTotalTrackInfo(); for (var i=0; i<totalTrackInfo.length;i++) { if (totalTrackInfo.type =='AUDIO') { console.log('Find audio track.'); console.log('audio track index is ' + totalTrackInfo.index); console.log('audio track language is ' + totalTrackInfo.extra_info.language); } }
-
Select the audio track.
Call thesetSelectTrack()
method with the track type and index number as parameters:// Select audio track with index 2 webapis.avplay.setSelectTrack('AUDIO',2);
DRM Contents Playback Sequence
You can play drm contents as setting drm properties for each drm case properly using setDrm()
method in IDLE
state.
And, as using ondrmevent()
callback function, you can handle errors caused by incorrect drm settings or environments, and in the PlayReady GenChallenge case or Widevine Modular case, you can get the challenge data from AVPlay
and get the license data from the license server through the corresponding the challenge data.
Below figures are sequence diagram for each drm case, you can refer to the detailed information at the link.
- drm support in streaming contents
- setDrm() method
- ondrmevent() callback
- drm version
- MSE/EME
-
PlayReady getrights case
This method is driven by theAVPlay
creation of challenge data and acquiring license data directly from license server and performing install it self. If license server require addition properties for acquiring license data(e.g. HTTP header, User agent, Cookie, etc.), application should callsetDrm("PLAYREADY", "SetProperties", json_object)
method with setting additional data corresponding to key and value of json object as the example code below. To execute this case, either set the value for "GetChallenge" into false or do not set "GetChallenge" property for "SetProperties" drmOperation insetDrm()
AVPlay API.- Sample code
function drmEventCallback(event, data) { if(data.name == "DrmError") { // error handling } } function prepareCallback() { webapi.avplay.play(); } var json = { "DeleteLicenseAfterUse" : true, // Optional field "Cookie":"Your Cookie", "LicenseServer" : "License server url", "HttpHeader" : "HTTP Header which license server required.", "UserAgent" : "Your User Agent" }; var properties = JSON.stringify(json); webapi.avplay.open(url); webapi.avplay.setListener({ondrmevent:drmEventCallback}); webapi.avplay.setDrm("PLAYREADY", "SetProperties", properties); webapi.avplay.setDisplayRect(0, 0, 1920, 1080); webapi.avplay.prepareAsync(prepareCallback); webapi.avplay.stop(); webapi.avplay.close();
- Sequence Diagram
- Sample code
-
PlayReady genchallenge case (Since Tizen 2018)
AVPlay
passes the challenge data to theondrmevent()
callback function. The application should acquire and install the license data usingsetDrm("PLAYREADY", "InstallLicense", license_data)
directly from the license server by usingjquery.ajax()
method,XMLHttpReuqest
class, etc. To execute this case, "GetChallenge" property for "SetProperties" drmOperation should set to true viasetDrm()
AVPlay API.- Sample code
function drmEventCallback(event, data) { // Challenge case if(data.name == "Challenge") { // request license data from license server (via HTTP POST) $.ajax({ url: license_server_url, data: atob(data.challenge), headers: { "Content-Type": "text/xml", }, type: 'POST', dataType: 'text', cache: false, processData: false }).success(function(msg, status) { webapi.avplay.setDrm("PLAYREADY", "InstallLicense", btoa(msg)); }); } else if(data.name == "DrmError") { // error handling } } function prepareCallback() { webapi.avplay.play(); } var json = { "DeleteLicenseAfterUse" : true, "GetChallenge" : true }; var properties = JSON.stringify(json); webapi.avplay.open(url); webapi.avplay.setListener({ondrmevent:drmEventCallback}); webapi.avplay.setDrm("PLAYREADY", "SetProperties", properties); webapi.avplay.setDisplayRect(0, 0, 1920, 1080); webapi.avplay.prepareAsync(prepareCallback); webapi.avplay.stop(); webapi.avplay.close();
- Sequence Diagram
- Sample code
-
Verimatrix case
- Sample code
function drmEventCallback(event, data) { if(data.name == "DrmError") { // error handling } } function prepareCallback() { webapi.avplay.play(); } var json = { "CompanyName" : YourCompany, "IPTV" : public2.example.verimatrix.com, Web : public-ott-nodrm.example.verimatrix.com:8080 }; var properties = JSON.stringify(json); webapi.avplay.open(url); webapi.avplay.setListener({ondrmevent:drmEventCallback}); webapi.avplay.setDrm("VERIMATRIX", "SetProperties", properties); webapi.avplay.setDisplayRect(0, 0, 1920, 1080); webapi.avplay.prepareAsync(prepareCallback); webapi.avplay.stop(); webapi.avplay.close();
- Sequence Diagram
- Sample code
-
Widevine Modular case
As withPlayReady genchallenge
scenario, the application should acquirelicense data
as challenge data to the license server and install usingsetDrm("WIDEVINE_CDM", "widevine_license_data", license_data)
.
When sending a request, the application should set the license server information (wvJson.license_server). And if necessary, the application can set the extra information (such as wvJson.wvheader).- Sample code
function drmEventCallback(event, data) { // Challenge case if(data.name == "Challenge") { // request license data from license server (via HTTP POST) var message = atob(data.challenge); // The challenge data is base64 encoded type. // <--The application should follow the server interface guide when acquiring license data --> var xmlhttp = new XMLHttpRequest(); xmlhttp.responseType = "arraybuffer"; xmlhttp.open("POST", wvJson.license_server, true); xmlhttp.setRequestHeader("pallycon-customdata", wvJson.wvheader); xmlhttp.onload = function(e) { if (this.status == 200) { if(this.response) { var licenseParam = data.session_id + "PARAM_START_POSITION" + btoa(this.response) + "PARAM_START_POSITION"; webapi.avplay.setDrm("WIDEVINE_CDM", "widevine_license_data", licenseParam); } } }; xmlhttp.send(message); //<-- server interface guide --> } else if(data.name == "DrmError") { // error handling } } function prepareCallback() { webapi.avplay.play(); } var json = { "AppSession" : YourAppSession, "DataType" : "matroska_webm" // The application should set DataType when the value is 'matroska_webm'. }; var properties = JSON.stringify(json); webapi.avplay.open(url); webapi.avplay.setListener({ondrmevent:drmEventCallback}); webapi.avplay.setDrm("WIDEVINE_CDM", "SetProperties", properties); webapi.avplay.setDisplayRect(0, 0, 1920, 1080); webapi.avplay.prepareAsync(prepareCallback); webapi.avplay.stop(); webapi.avplay.close();
- Sequence Diagram
- Sample code
State Limitations for AVPlay API Methods
The following table lists the AVPlay API methods and their valid states. Unless otherwise specified, calling the method does not change the state of the AVPlay
instance.
Method | Valid States | Notes |
---|---|---|
getVersion()
|
any | - |
open()
|
NONE, IDLE | After a successful call during a valid state, the instance enters the IDLE state. |
prepare()
|
IDLE, READY | After a successful call during a valid state, the instance enters the READY state. |
prepareAsync()
|
||
play()
|
READY, PLAYING, PAUSED | After a successful call during a valid state, the instance enters the PLAYING state. |
pause()
|
PLAYING, PAUSED | After a successful call during a valid state, the instance enters the PAUSED state. |
stop()
|
any | After a successful call, the instance enters the IDLE state. |
close()
|
After a successful call, the instance is removed and enters the NONE state. | |
setDisplayRect()
|
IDLE, READY, PLAYING, PAUSED | - |
seekTo()
|
||
jumpForward()
|
READY, PLAYING, PAUSED | |
jumpBackward()
|
||
getState()
|
any | |
getDuration()
|
||
getCurrentTime()
|
||
setListener()
|
||
setSpeed()
|
READY, PLAYING, PAUSED | |
setDrm()
|
NONE, IDLE | NONE state is supported for Verimatrix "GetUID" operation only |
setExternalSubtitlePath()
|
IDLE, READY, PLAYING, PAUSED | - |
setSubtitlePosition()
|
PLAYING, PAUSED | |
setSilentSubtitle()
|
IDLE, READY, PLAYING, PAUSED | |
setDisplayMethod()
|
||
setSelectTrack()
|
READY, PLAYING, PAUSED | READY state is supported for Smooth Streaming only |
getTotalTrackInfo()
|
READY state is supported for synchronous prepare method only | |
getCurrentStreamInfo()
|
- | |
setStreamingProperty()
|
IDLE | |
getStreamingProperty()
|
READY, PLAYING, PAUSED | |
setBufferingParam()
|
IDLE | |
suspend()
|
READY, PLAYING, PAUSED | |
restore()
|
PLAYING, PAUSED |
Table 4. AVPlay API method state limitations