Streaming media overview:
The so-called streaming media refers to the media format played on the Internet by means of streaming transmission.
Streaming media is also known as streaming media, it means that businesses use a video delivery server to send programs as data packets to the network.
After the user decompresses the data through the decompression device, the program will be displayed as before.
Streaming media transmits audio, video and multimedia files in the network by streaming.
Streaming media file format is a media format that supports streaming transmission and playback.
Streaming transmission mode is to divide multimedia files such as video and audio into compression packages through special compression mode,
Continuous and real-time transmission from the server to the user's computer. In the streaming system, users don't have to wait for the whole file like non streaming
Only after all the downloads are completed can we see the contents, but only after a few seconds or dozens of seconds of startup delay can we use them on the user's computer
The corresponding player will play the compressed video or audio and other streaming media files, and the rest will continue to download until the end of playing.
RTP :(Real-time Transport Protocol)
RTP is a transport layer protocol for multimedia data stream on Internet. RTP is used together with RTCP, and it is based on UDP protocol
Unlike HTTP and FTP, RTP can download the entire video file completely. It sends data on the network at a fixed data rate. The client also watches the video file at this speed. When
After the film and television picture is played, it can not be played again, unless the data is requested from the server again.
RTCP:Real-time Transport Control protocol or RTP (control protocol or RTCP)
RTCP is a sister protocol of RTP
Note: -: RTP protocol and RTCP are used together, and it is based on UDP protocol (generally used for video conference)
RTSP:(Real Time Streaming Protocol)
Real time streaming media session protocol, SDP (Session Description Protocol), RTP (real time Transport Protocol).
RTSP is a multimedia streaming protocol used to control sound or video. RTSP provides an extensible framework, which makes it possible to control and demand real-time data, such as audio and video.
Media data use RTP, RTCP protocol.
Generally, UDP is used as the transport layer. Suitable for IPTV scenes.
Data sources include field data and data stored in clips. The purpose of this protocol is to control multiple data transmission connections and provide a way to select transmission channels, such as UDP, multicast UDP and TCP
It also provides a method for selecting the transmission mechanism based on RTP
The network protocol used in transmission is not in the scope of its definition. The server can choose to use TCP or UDP to transmit the stream content, which is more tolerant of network delay
--->The biggest difference between RTSP and RTP is that RTSP is a two-way real-time data transmission protocol, which allows the client to send requests to the server, such as playback, fast forward, backward and so on. When
However, RTSP can transmit data based on RTP, and can also select TCP, UDP, multicast UDP and other channels to send data, which has good scalability. It is similar to the HTTP protocol
Network application layer protocol
WebRTC:
The protocol of streaming media is implemented on the web. When Google first launched webrtc, the giants either looked on coldly or resisted. RTP protocol is used for transmission.
RTMP(Real Time Messaging Protocol)
Macromedia developed a set of live video protocol, now belongs to adobe. Like HLS, it can be applied to live video, and it will not be lost based on TCP.
//The difference is that RTMP can't play in IOS browser based on flash, but its real-time performance is better than HLS.
Real time messaging protocol is an open protocol developed by Adobe Systems for audio, video and data transmission between flash player and server
//In IOS code, RTMP is commonly used to push streaming. You can use the third-party library librtmp IOS to push streaming. Librtmp encapsulates some core APIs for users to call
RTMP protocol also requires client and server to establish RTMP connection through "handshake", and then transmit control information on the connection. The RTMP protocol will format the data during transmission. In order to achieve better multiplexing, subcontracting and information fairness, the sender will divide the message into chunks with message ID, and each chunk may be a separate message,
It may also be a part of the message. The receiver will restore the chunk to a complete message according to the length of data, message ID and message contained in the chunk, so as to send and receive information.
HLS:HTTP Live Streaming(HLS)
It is an HTTP based streaming media transport protocol implemented by Apple Inc,
It can realize live and on-demand streaming media, mainly used in IOS system
To provide audio and video live and on-demand solutions for IOS devices (such as iPhone and iPad).
HLS on demand is basically a common segmented HTTP on demand. The difference is that its segments are very small.
Compared with the common live streaming protocols, such as RTMP protocol, RTSP protocol, MMS protocol and so on, the biggest difference of HLS live streaming is that what the live streaming client obtains is not a complete message
The whole data stream.
The HLS protocol stores the live data stream as continuous, short-term and long media files (mpeg-ts format) on the server side, while the client side continuously downloads and plays these small files,
Because the server always generates new small files from the latest live data, so as long as the client continuously plays the files obtained from the server in order, the live broadcast is realized.
It can be seen that, basically, HLS is based on > > on-demand technology to achieve live < <. Because the data is transmitted through HTTP protocol, there is no need to consider the firewall or proxy
Moreover, the length of segmented file is very short, so the client can quickly select and switch the code rate to adapt to the playback under different bandwidth conditions. However, this kind of technical characteristics of HLS determines its future development
Generally, the delay is always higher than the normal live streaming protocol.
//Both IOS and Android naturally support this protocol, and the configuration is simple. You can use the video tag directly
***VLS: is a kind of streaming server, which is specially used to solve various problems of streaming. It also has some characteristics of VLC. As a server, videolan can output HTTP, RTP and RTSP streams.
In principle, RTSP, RTMP and HTTP can be used for live and on-demand broadcasting, but generally RTSP and RTMP are used for live broadcasting and HTTP is used for on-demand broadcasting. We choose RTMP protocol.
Delay of various protocols and its causes
RTMP and httpflv: the data of these two protocols are roughly the same, so the reasons for delay are similar. It is reasonable to say that the delay of TCP streaming live broadcasting is very low. Why is there delay in RTMP and httpflv? The reason is that on h264, RTMP and httpflv are both transmitted flv tags. The data of video tag is usually H264 data. H264 decoding has an IBP. I is the key frame, which is a complete image. You must first have an I to decode the following BP. The number of BP frames can be as few as you like, but the number of I frames can't be less, so I frames must be in flv Tag transmission is the second transmission (the first one is h264spps). However, I-frames are not common in H264 streams. There is only one I-frame after another. This interval is commonly known as GOP. When encoding, GOP is set very short. When the client connects, the server will find the latest I-frame in the stream at the fastest speed and send live data from I-frame. However, when GOP is very long, I-frame interval is very long , or wait for the next I frame to start sending data to the new connection, or find the latest I frame in the cache to start sending. This is the key to the delay of RTMP and HLS protocols. In major CDN platforms, it is called "RTMP second on technology". The principle is to decode the streaming data twice and set a small GOP. In general, when GOP is set to 1s, regardless of the network transmission link delay, the maximum data delay is 1s. Fortunately, I frame is 0 delay!
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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
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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
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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.
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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
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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
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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.
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* 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.
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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: |
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