Introduction
With the launch of Flash Player 11 (4th Ocotober 2011) Adobe introduced the H.264 video codec in Flash Player for video encoding. For those of you who don’t know yet what H.264 is, it is a standard for video compression, and is currently one of the most commonly used formats for the recording, compression, and distribution of high definition video. The final drafting work on the first version of the standard was completed in May 2003.
The Problems:
There are 3 major media servers on the market: FMIS, Red5 and Wowza. All three are supported by HDFVR, our video recording product.
From these three only FMIS and Wowza can produce mp4 files. Red5 can’t save the audio and video data in mp4 files.
None of them can produce MP4 files with AAC audio because the only audio encoding codecs available in Flash Player are NellyMoser’s ASAO and Speex and none of these audio codecs are recommended with MP4 containers.
In addition FMIS produces mp4 files using an industry-standard recording technology known as “fragments” or “moof atoms.” Some MPEG-4 compatible tools and players do not support moof atoms and therefore cannot recognize files recorded by Adobe Media Server unless they are post-processed with a tool called F4V Post Processor that can be downloaded from here.
The solution:
After digging deeper into the problem we’ve came across the Transcoder addon for Wowza. The Transcoder takes a live stream, decodes the video and audio and then re-encodes the data to suit your needs (delivery to iOS devices, etc.). It seems it works just as good for recording streams.
To produce mp4 files with H.264 video and AAC audio we need the Transcoder to
- take in the audio and video data coming from HDFVR,
- leave the video intact,
- decode the audio and re-encode it with AAC
- put everything back in an .mp4 file
With a few configurations tweaks for HDFVR we’ve managed to do that. Let’s see how we’ve done it.
Requirements
Here’s everything we need (download and install step by step):
When running Wowza on Windows you will also need:
- .NET Framework 3.5.1 Feature (download)
- Desktop Experience if you run Windows Server (details)
After installing everything, including the Transcoder you have to start Wowza in standalone mode. To do so you have to run startup.bat (on Windows) or startup.sh (on Linux) inside Wowza/bin folder.
Once Wowza is started, at the beginning of the log messages in the command line window you should see a message telling you that the Transcoder is available (at the beginning of the console screen). The message should look something like this: INFO server comment – Transcoder Streams Available.
In case your Transcoder appears as unavailable you should check the log messages in the console window that show the Java version. The correct line should look like this : : INFO server comment – Java Architecture: 64. If this is not correct you should try install Java again and set your Java path, details here.
Important note about Wowza Patch:
After testing with the latest Wowza (at the time of writing this article it was 3.0.3) and the Transcoder we’ve found that the recorded mp4 files could not be played with any external player. After researching a little bit we’ve came across a patch for Wowza that fixed this problem. The patch can be found here : http://www.wowza.com/downloads/WowzaMediaServer-3-0-3/WowzaMediaServer3.0.3-patch3.zip .
You will need to replace the files inside of your Wowza installation folder with the ones inside the patch (only the files contained inside the patch).
Wowza (3.1.1) even though is newer than the one we used does not contain this patch.
After getting everything above installed and running follow these steps to configure HDFVR and Wowza/Trnascoder addon for recording mp4 files with AAC audio and h.264 video.
Step 1 : Setting up HDFVR
1.1 Set the proper Audio Video Quality Profile in HDFRV
First we need to tell HDFVR we’re using Wowza + the Transcoder addon.
Set <vcodec> tag to h264_w_t in the video quality profile of your choice and the <snd> tag to speex10 as in the screenshot below.
By default HDFVR uses the following video quality profile files depending on the HTML page that embeds HDFVR:
- VideoRecorder.html -> audio_video_quality_profiles/320x240x30x90.xml
- VideoRecorder-api.html -> audio_video_quality_profiles/320x240x30x90.xml
- VideoRecorder-sd-16by9.html -> audio_video_quality_profiles/wide/640x360x30x90.xml
- VideoRecorder-hd.html -> audio_video_quality_profiles/wide/1280x720x30x90.xml
Here’s the <vcodec>tag properly set to h264_w_t in the 320x240x30x90.xml video quality profile file.
This will produce a stream with video encoded with h.264 and audio encoded with Speex or NellyMoser (the Transcoder can decode both so the sound codec choice does not matter) but upon reaching the media server Wowza will know that it has to transcode the audio.
speex10 will produce an audio stream containing 16khz audio at 42.2kbits/s.
According to the transcoder guide, Wowza does not know to decode NellyMoser’s ASAU audio codec so don’t use it, use Speex.
1.2 Configure Application.xml
The next step is configure the Application.xml file for HDFVR. The Application.xml file for HDFVR is found inside Wowza/conf/hdfvr directory. Here’s what you need to change from the default Application.xml with which HDFVR is delivered:
- set the <StreamType> tag to live-record.
- uncomment the <LiveStreamPacketizers> and make sure it’s set to cupertinostreamingpacketizer, smoothstreamingpacketizer, sanjosestreamingpacketizer
- uncomment the <Transcoder> and <HTTPStreamers> tags
- set the <LiveStreamTranscoder> tag to transcoder (this will enable the Transcoder addon)
- set the <HTTPStreamers> tag to cupertinostreaming,smoothstreaming,sanjosestreaming
If these options are not present in your Application.xml please add them. Make sure that they are not commented.
Your Application.xml should look like this:
<Root>
<Application>
<!-- Uncomment to set application level timeout values
<ApplicationTimeout>60000</ApplicationTimeout>
<PingTimeout>12000</PingTimeout>
<ValidationFrequency>8000</ValidationFrequency>
<MaximumPendingWriteBytes>0</MaximumPendingWriteBytes>
<MaximumSetBufferTime>60000</MaximumSetBufferTime>
<MaximumStorageDirDepth>25</MaximumStorageDirDepth>
-->
<Connections>
<AutoAccept>true</AutoAccept>
<AllowDomains></AllowDomains>
</Connections>
<!--
StorageDir path variables
${com.wowza.wms.AppHome} - Application home directory
${com.wowza.wms.ConfigHome} - Configuration home directory
${com.wowza.wms.context.VHost} - Virtual host name
${com.wowza.wms.context.VHostConfigHome} - Virtual host config directory
${com.wowza.wms.context.Application} - Application name
${com.wowza.wms.context.ApplicationInstance} - Application instance name
-->
<Streams>
<StreamType>live-record</StreamType>
<StorageDir>${com.wowza.wms.context.VHostConfigHome}/content</StorageDir>
<KeyDir>${com.wowza.wms.context.VHostConfigHome}/keys</KeyDir>
<LiveStreamPacketizers>cupertinostreamingpacketizer, smoothstreamingpacketizer, sanjosestreamingpacketizer</LiveStreamPacketizers>
<Properties>
</Properties>
</Streams>
<Transcoder>
<!-- To turn on transcoder set to: transcoder -->
<LiveStreamTranscoder>transcoder</LiveStreamTranscoder>
<!-- [templatename].xml or ${SourceStreamName}.xml -->
<Templates>hdfvr.xml</Templates>
<ProfileDir>${com.wowza.wms.context.VHostConfigHome}/transcoder/profiles</ProfileDir>
<TemplateDir>${com.wowza.wms.context.VHostConfigHome}/transcoder/templates</TemplateDir>
<Properties>
</Properties>
</Transcoder>
<HTTPStreamers>cupertinostreaming,smoothstreaming,sanjosestreaming</HTTPStreamers>
<SharedObjects>
<StorageDir></StorageDir>
</SharedObjects>
<Client>
<IdleFrequency>-1</IdleFrequency>
<Access>
<StreamReadAccess>*</StreamReadAccess>
<StreamWriteAccess>*</StreamWriteAccess>
<StreamAudioSampleAccess></StreamAudioSampleAccess>
<StreamVideoSampleAccess></StreamVideoSampleAccess>
<SharedObjectReadAccess>*</SharedObjectReadAccess>
<SharedObjectWriteAccess>*</SharedObjectWriteAccess>
</Access>
</Client>
<RTP>
<!-- RTP/Authentication/[type]Methods defined in Authentication.xml. Default setup includes; none, basic, digest -->
<Authentication>
<PublishMethod>digest</PublishMethod>
<PlayMethod>digest</PlayMethod>
</Authentication>
<!-- RTP/AVSyncMethod. Valid values are: senderreport, systemclock, rtptimecode -->
<AVSyncMethod>senderreport</AVSyncMethod>
<MaxRTCPWaitTime>12000</MaxRTCPWaitTime>
<IdleFrequency>75</IdleFrequency>
<RTSPSessionTimeout>90000</RTSPSessionTimeout>
<RTSPMaximumPendingWriteBytes>0</RTSPMaximumPendingWriteBytes>
<RTSPBindIpAddress></RTSPBindIpAddress>
<RTSPConnectionIpAddress>0.0.0.0</RTSPConnectionIpAddress>
<RTSPOriginIpAddress>127.0.0.1</RTSPOriginIpAddress>
<IncomingDatagramPortRanges>*</IncomingDatagramPortRanges>
<!-- Properties defined here will override any properties defined in conf/RTP.xml for any depacketizers loaded by this application -->
<Properties>
</Properties>
</RTP>
<Modules>
<Module>
<Name>base</Name>
<Description>Base</Description>
<Class>com.wowza.wms.module.ModuleCore</Class>
</Module>
<Module>
<Name>properties</Name>
<Description>Properties</Description>
<Class>com.wowza.wms.module.ModuleProperties</Class>
</Module>
<Module>
<Name>logging</Name>
<Description>Client Logging</Description>
<Class>com.wowza.wms.module.ModuleClientLogging</Class>
</Module>
<Module>
<Name>flvplayback</Name>
<Description>FLVPlayback</Description>
<Class>com.wowza.wms.module.ModuleFLVPlayback</Class>
</Module>
<Module>
<Name>customServerHDFVR</Name>
<Description>Server HDFVR</Description>
<Class>com.naicuandnaicu.server.MyModule</Class>
</Module>
</Modules>
<!-- Properties defined here will be added to the IApplication.getProperties() and IApplicationInstance.getProperties() collections -->
<Properties>
</Properties>
</Application>
</Root>
You can download the above Application.xml code/file from here: http://codeviewer.org/view/code:26eb.
1.3 Setting up a Wowza application for playback:
Now we are ready to record mp4 files on Wowza but how about playing them inside of HDFVR.
Because the <StreamType> tag is set to live-record inside Application.xml after you finish recording you will not be able to play back the file. The stream can only be played only while it’s being recorded because Wowza treats it as a live stream.
Not to worry though because we have a solution. Wowza is storing the recorded files inside a folder (Wowza/content) that is shared by all the applications so all we need to do now is set up another app with a different <StreamType> tag that will recognize the files as recorded streams and play them back properly.
On your Wowza media server you will have to copy the hdfr_play files (they’re in the HDFVR build 508 (beta version) archive) as a normal application and the rest is done automatically by HDFVR.
The Application.xml for the hdfr_play app (Wowza/conf/hdfvr_play) should have the <StreamType> tag set to record.
For those of you who do not use HDFVR and want a better understanding of how it works the principle is pretty straight forward: HDFVR connects to one application (hdfvr) with its set of settings and uses the Transcoder addon to record mp4 files. To play the files HDFVR connects to another application (hdfvr_play) with a different set of settings.
Step 2: Setting up the Transcoder
Inside Application.xml for the hdfvr app (Wowza/conf/hdfvr) mentioned the following things are specified:
- the <Transcoder> tag contains the information about where the configuration file for the addon can be found,
- the <TemplateDir> tag contains the path to the templates folder,
- the <Templates> tag contains the name of the template file to use and it has the following value hdfvr.xml .
Here’s the contents of hdfvr.xml, copy and paste it in a hdfvr.xml file inside your Wowza/transcoder/templates folder.
<Root>
<Transcode>
<Encodes>
<!-- Example Encode block for source, not required unless Member of StreamNameGroup. -->
<Encode>
<Enable>true</Enable>
<Name>aac</Name>
<StreamName>mp4:${SourceStreamName}</StreamName>
<Video>
<!-- H.264, PassThru, Disable -->
<Codec>PassThru</Codec>
<Bitrate>${SourceVideoBitrate}</Bitrate>
<Parameters>
</Parameters>
</Video>
<Audio>
<!-- AAC, PassThru, Disable -->
<Codec>AAC</Codec>
<Bitrate>48000</Bitrate>
</Audio>
<Properties>
</Properties>
</Encode>
</Encodes>
<Decode>
</Decode>
<StreamNameGroups>
</StreamNameGroups>
<Properties>
</Properties>
</Transcode>
</Root>
Here’s the above doe explained:
- The <StreamName> tag will tell the Transcoder to produce an mp4 file.
- The <Video> tag will leave the video untouched as the <Codec> tag is set to PassThru and the <Bitrate> tag is set to the maintain the source’s one.
- The <Audio> tag will encode audio as AAC set through the <Codec> tag and a bitrate of 48000 set through the <Bitrate> tag.
Results
After all this set up is time to run HDFVR in the browser. Press the record button and have fun. After you finished recording press play. If the recorded file does not play go back and see the section about the hdfvr_play app. To see the recorded mp4 files go to Wowza/content folder.
Conclusion
I m sure most of you know why mp4 files are useful but for those of you who can’t quite get why this is a major feature here it goes: Flash Player is not supported by iOS and Android Internet Browsers thus .flv files can not be played on these devices. With this feature you will now be able to play you recordings straight away on any type of OS.
There are many possibilities offered by the Transcoder add on not just recording mp4 files but saving different copies of your file with different quality settings , making playlists and so forth (the documentation is available here) , all you have to do is to configure the Transcoder configuration file hdfvr.xml to suit your needs.
Halloween is upon us again this year and we have some special prices this week for you guys.
) most probably our products will work with it out of the box (as always).
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