The open source code live555 is the SDK used to implement the streaming media transmission function. Use the play Common.cpp in the teSTProgs folder in the SDK to design the transmission module of the IP TV set-top box, and together with the playback module constitute the streaming media player of the IPTV set-top box process. playCommon. cpp is a bridge connecting the server and the client. Its working principle is that when the client requests data from the server, it obtains the SDP description information from the server URL and creates a multimedia session based on the SDP, and finally plays the data stream.
introduced the design process of IPTV set-top box streaming media player, using the function of playCommON.cpp in live555 open source code, combined with the software structure design of IPTV set-top box, developed the transmission module of IPTV set-top box. Then the transmission module is connected with the middleware through the message queue, and at the same time is connected with the playback module through the entry function of the playback module, and finally constitutes the streaming media player of the IPTV set-top box. The player has been tested and has stable performance.
1 IPTV set-top box streaming media player design
1. 1 IPTV set-top box software structure
The software code of set-top box is divided into 4 parts: hardware driver, operating system, middleware, application layer.
1) The hardware driver connects the underlying hardware and the upper operating system. 2) Operating system The free open source code Linux is used here. 3) Middleware The software adaptation layer that isolates the upper application layer from the underlying operating system and hardware. The core modules of the middleware mainly include: (1) Browser: Obtain the URL from the server and display the corresponding EPG page. (2) Graphical user interface management: provide graphic functions such as user interface control (such as buttons, lists) and graphic image drawing for applications. 4) The application layer realizes the playback of audio and video media files.
1.2 IPTV set-top box streaming media player system structure
In the Live555 open source code, playCommon.cpp realizes the function of using a computer as a receiving terminal, receiving and playing with VLC software, and finally displaying it on the computer. The content of the research is to integrate playCommon.cpp into the software code of the set-top box, and finally realize the function of using the IPTV set-top box as the receiving terminal and playing it and displaying it on the TV. This puts forward new requirements for the design of the code: On the one hand, playCommon.cpp obtains the URL of the server by entering rtsp ://local IP address: port number/file name to be played in the RTSP column of VLC. Acquired. However, for the IPTV set-top box, the URL obtained by the transmission module is the corresponding URL when the user selects the program on the EPG through the remote control. This URL is read by the browser in the middleware, so it is necessary to connect the middleware and the transmission module stand up. On the other hand, the data stream sent by playCommon.cpp is received and played through VLC. For IPTV set-top boxes, the data stream sent by the transmission module is received and played through the playback module. Therefore, it is necessary to connect the transmission module and the playback module.
In order to connect the middleware, the output module and the playback module, a message queue is designed to realize the data communication between these three modules. In addition, pt hread create () is also designed in the program to create thread rt spmain() to realize the concurrency of the program.
1.3 Program structure analysis
1.3.1 Transmission module.
1) main function (1) void initMsgQ () initializes the message queue. dataQid represents the message queue of data, which contains some data transmitted on the network. Finally, the data in the message queue is sent to the player through the void send data to player () function. msgkeyQid represents the message queue of the message key value. The transmission module receives the remote control key value command obtained from the middleware and sends it to the player to realize fast forward, fast rewind, stop, and playback operations. fromeMiddleQid represents the message queue of the middleware. The transmission module receives the URL sent from the middleware as the destination address when the client player requests data from the server. playerStateQid represents the message queue of the playing state. The transmission module is used to send and receive the state of the player, and to control whether the player is on-demand, live or time shift. (2) phread_create(&g_session_thread_info ,&tattr,(void*(*)(void*))rtsp_main ,(void*)&urlInform); Create rtsp_main() thread. Ensure that the communication of the message queue and the transmission of the streaming media run simultaneously.
2) rtsp_main function. (1) recvMiddlewareMsg(fromeMiddleQid, url): The value of the url passed from the middleware is assigned to the variable url. (The definition of url is completed in the middleware, so it needs to be obtained from the middleware); (2) playCommon.cpp Function: When the client sends a request to the server, the server responds to the request, creates a media session and plays the data stream. (3) main_player_entry(gTrans. first Create): The client receives the stream and calls the player's entry function to initialize the player. (4) void send_data_to_player(): call the player, send the data received from the Internet to the player, and start playing.
|
|
|
|
How far(long) the transmitter cover?
The transmission range depends on many factors. The true distance is based on the antenna installing height , antenna gain, using environment like building and other obstructions , sensitivity of the receiver, antenna of the receiver . Installing antenna more high and using in the countryside , the distance will much more far.
EXAMPLE 5W FM Transmitter use in the city and hometown:
I have a USA customer use 5W fm transmitter with GP antenna in his hometown ,and he test it with a car, it cover 10km(6.21mile).
I test the 5W fm transmitter with GP antenna in my hometown ,it cover about 2km(1.24mile).
I test the 5W fm transmitter with GP antenna in Guangzhou city ,it cover about only 300meter(984ft).
Below are the approximate range of different power FM Transmitters. ( The range is diameter )
0.1W ~ 5W FM Transmitter ：100M ~1KM
5W ~15W FM Ttransmitter : 1KM ~ 3KM
15W ~ 80W FM Transmitter : 3KM ~10KM
80W ~500W FM Transmitter : 10KM ~30KM
500W ~1000W FM Transmitter : 30KM ~ 50KM
1KW ~ 2KW FM Transmitter : 50KM ~100KM
2KW ~5KW FM Transmitter : 100KM ~150KM
5KW ~10KW FM Transmitter : 150KM ~200KM
How to contact us for the transmitter?
Call me +8618078869184 OR
Email me [email protected]
1.How far you want to cover in diameter ?
2.How tall of you tower ?
3.Where are you from ?
And we will give you more professional advice.
About Us
FMUSER.ORG is a system integration company focusing on RF wireless transmission / studio video audio equipment / streaming and data processing .We are providing everything from advice and consultancy through rack integration to installation, commissioning and training.
We offer FM Transmitter, Analog TV Transmitter, Digital TV transmitter, VHF UHF Transmitter, Antennas, Coaxial Cable Connectors, STL, On Air Processing, Broadcast Products for the Studio, RF Signal Monitoring, RDS Encoders, Audio Processors and Remote Site Control Units, IPTV Products, Video / Audio Encoder / Decoder, designed to meet the needs of both large international broadcast networks and small private stations alike.
Our solution has FM Radio Station / Analog TV Station / Digital TV Station / Audio Video Studio Equipment / Studio Transmitter Link / Transmitter Telemetry System / Hotel TV System / IPTV Live Broadcasting / Streaming Live Broadcast / Video Conference / CATV Broadcasting system.
We are using advanced technology products for all the systems, because we know the high reliability and high performance are so important for the system and solution . At the same time we also have to make sure our products system with a very reasonable price.
We have customers of public and commercial broadcasters, telecom operators and regulation authorities , and we also offer solution and products to many hundreds of smaller, local and community broadcasters .
FMUSER.ORG has been exporting more than 15 years and have clients all over the world. With 13 years experience in this field ,we have a professional team to solve customer's all kinds of problems. We dedicated in supplying the extremely reasonable pricing of professional products & services. Contact email : [email protected]
Our Factory
We have modernization of the factory . You are welcome to visit our factory when you come to China.
At present , there are already 1095 customers around the world visited our Guangzhou Tianhe office . If you come to China , you are welcome to visit us .
At Fair
This is our participation in 2012 Global Sources Hong Kong Electronics Fair . Customers from all over the world finally have a chance to get together.
Where is Fmuser ?
You can search this numbers " 23.127460034623816,113.33224654197693 " in google map , then you can find our fmuser office .
FMUSER Guangzhou office is in Tianhe District which is the center of the Canton . Very near to the Canton Fair , guangzhou railway station, xiaobei road and dashatou , only need 10 minutes if take TAXI . Welcome friends around the world to visit and negotiate .
Contact: Sky Blue
Cellphone: +8618078869184
WhatsApp: +8618078869184
Wechat: +8618078869184
E-mail: [email protected]
QQ: 727926717
Skype: sky198710021
Address: No.305 Room HuiLan Building No.273 Huanpu Road Guangzhou China Zip:510620
|
|
|
|
English: We accept all payments , such as PayPal, Credit Card, Western Union, Alipay, Money Bookers, T/T, LC, DP, DA, OA, Payoneer, If you have any question , please contact me [email protected] or WhatsApp +8618078869184
-
PayPal.  www.paypal.com
We recommend you use Paypal to buy our items ,The Paypal is a secure way to buy on internet .
Every of our item list page bottom on top have a paypal logo to pay.
Credit Card.If you do not have paypal,but you have credit card,you also can click the Yellow PayPal button to pay with your credit card.
---------------------------------------------------------------------
But if you have not a credit card and not have a paypal account or difficult to got a paypal accout ,You can use the following:
Western Union.  www.westernunion.com
Pay by Western Union to me :
First name/Given name: Yingfeng
Last name/Surname/ Family name: Zhang
Full name: Yingfeng Zhang
Country: China
City: Guangzhou
|
---------------------------------------------------------------------
T/T . Pay by T/T (wire transfer/ Telegraphic Transfer/ Bank Transfer)
First BANK INFORMATION (COMPANY ACCOUNT):
SWIFT BIC: BKCHHKHHXXX
Bank name: BANK OF CHINA (HONG KONG) LIMITED, HONG KONG
Bank Address: BANK OF CHINA TOWER, 1 GARDEN ROAD, CENTRAL, HONG KONG
BANK CODE: 012
Account Name : FMUSER INTERNATIONAL GROUP LIMITED
Account NO. : 012-676-2-007855-0
---------------------------------------------------------------------
Second BANK INFORMATION (COMPANY ACCOUNT):
Beneficiary: Fmuser International Group Inc
Account Number: 44050158090900000337
Beneficiary's Bank: China Construction Bank Guangdong Branch
SWIFT Code: PCBCCNBJGDX
Address: NO.553 Tianhe Road, Guangzhou, Guangdong,Tianhe District, China
**Note: When you transfer money to our bank account, please DO NOT write anything in the remark area, otherwise we won't be able to receive the payment due to government policy on international trade business.
|
|
|
|
* It will be sent in 1-2 working days when payment clear.
* We will send it to your paypal address. If you want to change address, please send your correct address and phone number to my email [email protected]
* If the packages is below 2kg,we will be shipped via post airmail, it will take about 15-25days to your hand.
If the package is more than 2kg,we will ship via EMS , DHL , UPS, Fedex fast express delivery,it will take about 7~15days to your hand.
If the package more than 100kg , we will send via DHL or air freight. It will take about 3~7days to your hand.
All the packages are form China guangzhou.
* Package will be sent as a "gift" and declear as less as possible,buyer don't need to pay for "TAX".
* After ship, we will send you an E-mail and give you the tracking number.
|
|
|
For Warranty .
Contact US--->>Return the item to us--->>Receive and send another replace .
Name: Liu xiaoxia
Address: 305Fang HuiLanGe HuangPuDaDaoXi 273Hao TianHeQu Guangzhou China.
ZIP:510620
Phone: +8618078869184
Please return to this address and write your paypal address,name,problem on note: |
|
