Have my blog theme changed

wordpress
I was using PageLines’s Platform theme for over 3 years, I really liked it.
It’s simple, fast, and easy to use.

The only problem is Platform theme does not mobile friendly, it’s sucked when you visit my blog by your smart phone. And this became the root reason of my decision of replacing it with a new theme.

And the new one is Customizr, designed by Press Customizr. Not so freshing as Platform, but seems good to me when I visit my blog by my phone. Wish you’d like it too.

Media Control(Video Picture Fast Update) mechanism for SIP

This question was origined from an experience of conferencing with different meeting terminals, including Polycom, Cisco, Tandburg, Huawei, etc.

In our current implementation of SIP conference, we are using a stream_id tag in the Video Fast Update command to  tell the peer we are requesting an Intra frame for a specific stream. And the stream_id tag value was recorded from the Label attribute of the SDP exchange process.
sip
However, this situation was:
1. Some of the vendors don’t have stream_id in the VideoFastUpdate command, such as CISCO and Tandburg, but if we send a VideoFastUpdate with stream_id tag in it, it doesn’t matter, it can response a 200 OK, only the stream_id value can not be zero, otherwise, it will reply with a 500 error.
2. Polycom does have a stream_id in it, but no matter what circumstances, the stream_id is alway 1.
3. Huawei seems have a same implementation with Kedacom, having a stream_id in it, and the value is coherence with the LABEL tag in the SDP.

Then I turned to the RFC document, RFC5168: XML Schema for Media Control, category: informational, developed by Microsoft, Polycom, Radvision.
The definition is placed in phase 5 of this document:
The Schema Definition

  <?xml version="1.0" encoding="utf-8" ?>

   <xs:schema id="TightMediaControl"
    elementFormDefault="qualified"
     xmlns:xs="http://www.w3.org/2001/XMLSchema">

           <xs:element name="media_control">
               <xs:complexType>
                  <xs:sequence>
                     <xs:element name="vc_primitive"
                                           type="vc_primitive"
                                           minOccurs="0"
                                           maxOccurs="unbounded" />
                     <xs:element name="general_error"
                                           type="xs:string"
                                           minOccurs="0"
                                           maxOccurs="unbounded" />
                  </xs:sequence>
               </xs:complexType>
           </xs:element>

           <!-- Video control primitive.  -->

           <xs:complexType name="vc_primitive">
                   <xs:sequence>
                     <xs:element name="to_encoder" type="to_encoder" />
                      <xs:element name="stream_id"
                                       type="xs:string"
                                       minOccurs="0"
                                       maxOccurs="unbounded" />
                           </xs:sequence>
           </xs:complexType>

           <!-- Encoder Command:
                Picture Fast Update
           -->

           <xs:complexType name="to_encoder">
                   <xs:choice>
                           <xs:element name="picture_fast_update"/>
                   </xs:choice>
           </xs:complexType>

   </xs:schema>

So, as you can see, there is actually a stream_id tag in it. But when I tried to find more about it, nothing was found. Weird enough for a RFC document.

After re-read the full document, found out there was a description which explains the situation:
New implementations are discouraged from using the method described except for backward compatibility purposes. New implementations are required to use the new Full Intra Request command in the RTP Control Protocol (RTCP) channel.

Failed to establish H.460 call through Polycom MCU issue

Details of the issue:

The situation is H600 can establish H.460 calls with most of the GKs around the world, but failed to a Polycom GK.
Allow me to explain the details of this issue:
1. Caller: Group500, callee: H600, GK/MCU: Polycom RMX 2000
2. Group500 sent a call to GK with callModel set to gatekeeperRouted, calling target: H600
3. GK sent H.460 SCI to H600
4. H600 replied SCR to GK
5. H600 established a H.225 TCP connection to the Polycom GK successfully
6. H600 sent facility to GK.
7. Polycom GK shutdown the H.225 TCP connection from H600 actively, and call terminated. Continue reading “Failed to establish H.460 call through Polycom MCU issue”

Students take VR to new heights with feedback-enabled gloves

vr-glovesA couple of engineering students from Rice University is taking virtual reality to the next level with a glove that lets you feel what you’re holding onto.

Much of the news regarding virtual reality is centered around our vision, but what makes reality better than virtual is that it tingles all five of our senses—not just our eyeballs.  Picking up a gun and firing it in real life is totally different from popping an alien in a video game.  The experience heightens when we get a true “3D” experience via gadgets like the Oculus, but that in itself is still an incomplete picture.

To make the VR experience even more exciting, some engineering students at Rice have developed a prototype glove that provide feedback when users interact with the virtual environment.  The glove is equipped with air bladders that expand and contract when fingers interact with the glove’s trigger mechanisms.  It weighs around 350 grams, but most of the glove’s weight is shoved towards the wrist area to give users the sense that it’s light enough to make it not noticeable.

The team says their underlying trigger mechanism is easily adaptable should programmers want to implement its protocol into games and other projects.

Source: Rice University

Nokia, Alcatel-Lucent merger arouses mixed feelings in Finland

Got the break/top news right after went back from the badminton field, what Should I say, Wow. Finally, eventually, Nokia is back, with this big move, looking forward to it’s next step to reveal the confuses in everyone’s mind.

Source: http://news.xinhuanet.com/english/2015-04/15/c_134154436.htm

Continue reading “Nokia, Alcatel-Lucent merger arouses mixed feelings in Finland”

Make VLC player to support play H.264 ES stream file

As I knew, H.264 ES stream file can be played back by CorePlayer(Commercial version of MPlayer).
But not VLC Player. But as I was told that someone did use VLC Player to player H.264 ES stream file.
So made some further dig into this issue, turned out the old version of VLC Player does support, while versions later than 1.0 doesn’t by default.
Continue reading “Make VLC player to support play H.264 ES stream file”

UniSVR is shutting down Shanghai office

April 1, 2015, a bright sunny day at Shanghai.
Today is supposed to be a kidding day, however, not got so much April Fool’s Day news as usual, but an astonishing news, UniSVR is going to shut down the Shanghai office in a month.

Sign, lament, or not, UniSVR Shanghai branch will be a history, finally annoncing and revealing the ending of a 15-year-old branch/office, where I participanted along with so much guys/gals there for more than ten years.

Sorry, regret, or not, life should and will go on. I talked with my previous boss, Mars Chen, VP of UniSVR, responsible for product and surveilance product line trategy, just minutes earlier. We did not talk about why, because we all knew it, it’s about business, it’s about life and living, and life always goes on.

Sad, pain, or not, let us all move on. Twelve years ago, the most shocking news was Leslie Cheung(张国荣) left us, it was really sad, and we could do nothing about it. Today, we moved on. One month later, UniSVR Shanghai will be closed, we can do nothing either, we will also move on. Besides this might leave UniSVR a clearer and brighter furture, I’m not saying this because I’m already left UniSVR, but truely from my heart.

And, I do care of UniSVR, although I resigned from UniSVR about two years ago.
I’m still keeping paying close attention to UniSVR.

And, lot’s of things happened in the almost two years.
In the two years, digital surveilance is no longer the tragical product for UniSVR.
In the two years, the bussiness in China mainland was keeping shrinking.
In the two years, lot’s of key employees left, new one came and left.
In the two years, developing work of IoT product, which is considered as the furture of UniSVR, was transfered from Shanghai to Beijing and Hsinchu.
Most importantly, some of us shared our youngness in UniSVR, especially, guys like Michael, Maggie, etc.

And we both knew
In the 15 years, UniSVR was once great not only in the global marketing, but also in China mainland.
In the 15 years, no matter where you sit in the orgnization chart, and no matter he/she worked hard or not, deep down in the heart, every UniSVRer kept fighting for a bright furture for both themself and UniSVR China.

I do feel sorry for myself that I didn’t get a chance to send my best wishes to UniSVR two years ago when I left UniSVR.
Back at that time, I planned myself a lot for the farewell, but the thing is not everything goes as you planned, so I choosed silience, only left a post on my blog, http://rg4.net/archives/455.html.
This time, allow me to speak it sincerely and loudly, God bless UniSVR, wish UniSVR a bright furture.

It seems today is even harder than the day I left UniSVR, it’s definitely a sleepless night for me, though I’m not know what I am thinking about, writing about.