Flex:还原火花VideoDisplay流

Question

编辑如果有人至少可以告诉我如何接收一个事件时，流断开，这将是很好的。

该控件的文档非常糟糕。我有一个具有实时视频流的应用程序，我正在寻找一种方法，使VideoDisplay控件恢复其连接，以防出现上述任何特定场景：

1. 应用程序启动，流尚未联机。
2. 应用程序正在流，用户与互联网断开连接。
3. ，应用程序正在流，视频服务器崩溃并重新启动。

我正在使用和Wirecast对此进行测试。1和3不起作用，我不确定2号有用。我添加了一段很有问题的代码，从而使第一条代码工作起来：

    protected function onMediaPlayerStateChange(event:MediaPlayerStateChangeEvent):void
    {
        if (event.state == MediaPlayerState.PLAYBACK_ERROR)
        {
            var videoSource:DynamicStreamingVideoSource = this.videoDisplay.source as DynamicStreamingVideoSource;

            try
            {
                this.videoDisplay.source = null;
                this.videoDisplay.source = videoSource;
            }
            catch (any:*) {}
        }
    }

正如您所看到的，我需要一个try/catch块，因为对源的两个调用都会导致异常，但是在这些异常之前发生的任何事情似乎都会修复问题#1。这并不能修复问题#3，因为当您停止视频服务器时，显然不会发生媒体状态更改事件。

这是我的控制声明：

<s:VideoDisplay id="videoDisplay" click="onVideoStreamClick(event)" mediaPlayerStateChange="onMediaPlayerStateChange(event)" muted="{this.videoMuted}" top="10" width="280" height="220" autoPlay="true" horizontalCenter="0">
    <s:source>
        <s:DynamicStreamingVideoSource id="videoSource" streamType="live" host="{FlexGlobals.topLevelApplication.parameters.videoStreamURL}">
            <s:DynamicStreamingVideoItem id="videoItemLow" streamName="{FlexGlobals.topLevelApplication.parameters.videoLow}" bitrate="{FlexGlobals.topLevelApplication.parameters.videoLowBitrate}" />
            <s:DynamicStreamingVideoItem id="videoItemMedium" streamName="{FlexGlobals.topLevelApplication.parameters.videoMedium}" bitrate="{FlexGlobals.topLevelApplication.parameters.videoMediumBitrate}" />
            <s:DynamicStreamingVideoItem id="videoItemHigh" streamName="{FlexGlobals.topLevelApplication.parameters.videoHigh}" bitrate="{FlexGlobals.topLevelApplication.parameters.videoHighBitrate}" />
        </s:DynamicStreamingVideoSource>
    </s:source>
</s:VideoDisplay>

有人知道如何使VideoDisplay从这些问题中恢复吗？任何帮助都是非常感谢的，谢谢。

Answer 1

如果有人有这个问题，我就是这样解决的。为了停止流，您需要将视频源设置为空白图像，否则它永远不会停止。此解决方案适用于上述所有场景：

    private function resetVideo():void
    {           
        //save current source object
        this.videoEventsDisabled = true;
        var videoSource:DynamicStreamingVideoSource = this.videoDisplay.source as DynamicStreamingVideoSource;

        try //switch to blank image, only this will stop the video stream
        {
            this.videoDisplay.source = "assets/images/video_offline.png";
        }
        catch (any:*) {}

        //wait a few seconds and reset video source
        setTimeout(resetVideoSource, 2000, videoSource);
    }

    private function resetVideoSource(videoSource:DynamicStreamingVideoSource):void
    {
        this.videoEventsDisabled = false;
        this.videoDisplay.source = videoSource;
    }

    protected function onMediaPlayerStateChange(event:MediaPlayerStateChangeEvent):void
    {
        if (this.videoEventsDisabled)
        {
            return;
        }

        //something went wrong
        if (event.state == MediaPlayerState.PLAYBACK_ERROR)
        {
            resetVideo();
        }
    }

    protected function onCurrentTimeChange(event:TimeEvent):void
    {
        if (this.videoEventsDisabled)
        {
            return;
        }

        //if there was a number before, and its suddendly NaN, video is offline
        if (isNaN(event.time) && !isNaN(this.previousVideoTime))
        {
            resetVideo();
        }
        else //store event time for future comparisons
        {
            this.previousVideoTime = event.time;
        }
    }

MXML：

<s:VideoDisplay id="videoDisplay" click="onVideoStreamClick(event)" mediaPlayerStateChange="onMediaPlayerStateChange(event)" currentTimeChange="onCurrentTimeChange(event)" muted="{this.videoMuted}" top="10" width="280" height="220" autoPlay="true" horizontalCenter="0">
    <s:source>
        <s:DynamicStreamingVideoSource id="videoSource" streamType="live" host="{FlexGlobals.topLevelApplication.parameters.videoStreamURL}">
            <s:DynamicStreamingVideoItem id="videoItemLow" streamName="{FlexGlobals.topLevelApplication.parameters.videoLow}" bitrate="{FlexGlobals.topLevelApplication.parameters.videoLowBitrate}" />
            <s:DynamicStreamingVideoItem id="videoItemMedium" streamName="{FlexGlobals.topLevelApplication.parameters.videoMedium}" bitrate="{FlexGlobals.topLevelApplication.parameters.videoMediumBitrate}" />
            <s:DynamicStreamingVideoItem id="videoItemHigh" streamName="{FlexGlobals.topLevelApplication.parameters.videoHigh}" bitrate="{FlexGlobals.topLevelApplication.parameters.videoHighBitrate}" />
        </s:DynamicStreamingVideoSource>
    </s:source>
</s:VideoDisplay>

Answer 2

作为一个变体，您可以处理来自NetStream对象的NetStream。

var _source:DynamicStreamingResource;
_source = new DynamicStreamingResource("rtmp://...", StreamType.LIVE);

var streamItems:Vector.<DynamicStreamingItem> = new Vector.<DynamicStreamingItem>();
streamItems.push(new DynamicStreamingItem(streamName, 0));

_source.streamItems = streamItems;

_rtmpDynamicStreamingNetLoader = new RTMPDynamicStreamingNetLoader();
_rtmpDynamicStreamingNetLoader.addEventListener(LoaderEvent.LOAD_STATE_CHANGE, rtmpDynamicStreamingNetLoaderStateChangeHandler);

var cvp:VideoDisplay = new VideoDisplay();

_source.mediaType = MediaType.VIDEO;

var videoElement:MediaElement = new VideoElement(_source, _rtmpDynamicStreamingNetLoader);

cvp.source = videoElement;

private function rtmpDynamicStreamingNetLoaderStateChangeHandler(event:LoaderEvent):void
{
    var netStream:NetStream = event.loadTrait["netStream"] as NetStream;
    if (netStream != null && !netStream.hasEventListener(NetStatusEvent.NET_STATUS)) {
        netStream.addEventListener(NetStatusEvent.NET_STATUS, netStreamNetStatusHandler, false, 0, true);
    }
}

private function netStreamNetStatusHandler(event:NetStatusEvent):void
{
    if (event.info.code == "NetStream.Play.UnpublishNotify") {

    }
    if (event.info.code == "NetStream.Play.PublishNotify") {

    }
 }

Answer 3

我用Johnatan的代码和JayPea的想法来解决我的问题！

我使用了Johnatan给出的所有内容，并在netStreamNetStatusHandler()中做了以下小改动：

private function netStreamNetStatusHandler(event:NetStatusEvent):void
{
    trace(event.info.code);

    if (event.info.code == "NetStream.Play.PublishNotify")
    {
        try
        {
            cvp.source = ''; //Doesn't need to be a valid path. Empty string should suffice.
        }
        catch (error:Error)
        {
            trace('Video source error: ' + error.message);
        }

        cvp.source = videoElement;
    }
}

这将在流停止和重新启动时重置源，从而导致视频显示再次播放。

注意:视频显示的autoPlay属性需要设置为“true”。