Voice Chat program implementation (INDY, ACM, DELPHI)

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The design, implementation and introduction of the chat program

Zhou Baofeng

Xi ' an Jiaotong University Software Institute MSE 2002

2005.01

Cable Primer

1 . Program Design ... 3

2 . Program Use ... 4

2.1 Use of the server ... 5

2.2 The use of the client ... 5

3. Reference Documents ... 6

1. Program Design

Programming Environment:

Using the Borland company Delphi 7 Enterprise Edition in the Windows 2000 Professional Edition development.

Other design Details:

TCP Server:

Use tidtcpserver <?xml:namespace prefix = v ns = "urn:schemas-microsoft-com:vml"/> implementation. The interaction for text.

For each client's TCP connection, start a threading process. The structure diagram is as follows:

Main thread

Listener Threads Accept Client 1 Accept Client 1 Accept Client 1 ...

Client1.thread

Client2.thread

Client3.thread

Thread management is managed with Tidthreadmgrdefault .

UDP Server:

Adopt the tidudpserver implementation in INDY. When the UDP packet is received, the Udpread event is triggered, where the sound data is played.

UDP client:

Adopt the Tidudpclient implementation in Indy. When the collected sound data exceeds the buffer
Size (2048 bytes), call its Sendbuffer method to emit the data.

Extraction of Sound:

Using the Tacmin control to collect sounds, the acmin control is primarily called the Windows API waveinopen function. function declaration:

function Waveinopen; External mmsyst name ' Waveinopen ';

(Mmsystem.pas)

Sound coding:

The default is GSM6.10 encoding, detailed coding support:

GSM 6.10 8kHz, mono– default

11.025kHz, Mono

22.050kHz, Mono

44.100 KHz, Mono

Micorsoft g.723.1 8 kHz Mono, 6400 bit/s

8 kHz Mono, 5333 bit/s

PCM 8/11/12/16/22/24/32/44/48 kHz, 8/16/bit, Mono

Mpet Layer–3

56/40/48/32/20/24/12/16/8 kbit/s, 24,000/22,000/16,000/8,000 Hz, Stereo

.....

Sound output:

When the UDP server receives the data, it plays with Acmout.

Adata.read (audioarray,adata.size);

If not audioout.active then BEGIN

With M_playaudioformat.format do begin

wFormatTag: = 1;

Nchannels: = 1;

Nsamplespersec: = 22050;

Navgbytespersec:= 22050;

Nblockalign:=1;

wBitsPerSample: = 8;

cbsize: = SizeOf (Tacmwaveformat);

End;

Adioout.open (Audioconvertor.formatin);

Audioout.open (M_playaudioformat);

End

Audioout.play (Audioarray, adata.size);

2. Program use

Note: Server programs and client programs cannot run on the same machine (avoid sound playback and collection conflicts), and a single machine can run only one server program or one client program at a time.
Server-side log files: CharSvr.log

Log file for client: ClientError.log

2.1 Use of the server

2.2 Use of clients

Select the online user before you can speak. 3. Reference documents

[1] Indy in Depth atozed Software