关于多媒体播放器VCD左右声道问题的BC代码

kmusttywyc

<>关于多媒体播放器在CB下声道转换的原代码！（DEPHI版的网上有）</P>
5 O: w: W5 R! p<>TSuperPlayerform *SuperPlayerform;
typedef struct
{
    DWORD dwCallback;
/ ]/ `. z7 p  x7 H0 b    DWORD dwItem;
" e* P) ^5 _+ Z4 M) r1 c    DWORD dwValue;
) w  k4 s) M; k2 O* ~    DWORD dwOver;
+ n; G/ N! q1 `# q4 k2 l    LPSTR lpstrAlgorithm;
9 i$ w. p' y) j. i7 S9 G    LPSTR lpstrQuality;
} MCI_DGV_SETAUDIO_PARMS;
   
7 J' {. v6 r7 [) |5 e const MCI_SETAUDIO = 0x873;
: p5 q& P- H& R4 B) p const MCI_SETVIDEO = 0x0876;
const MCI_DGV_SETAUDIO_SOURCE_LEFT=1;
const MCI_DGV_SETAUDIO_SOURCE_STEREO=0;
$ I3 k8 c% g  i' { const MCI_DGV_SETAUDIO_SOURCE_RIGHT=2;
const MCI_DGV_SETAUDIO_SOURCE=0x4004;
const MCI_DGV_SETAUDIO_VOLUME=0x4002;
! f) t1 \$ ?4 ?' V$ W1 L+ u3 b const MAX_VOLUME=65535;
: P& G; H$ H7 I" w: c3 e! |+ }' u const MIN_VOLUME=0;</P>
* }5 _5 D% v* ~+ ]( j# h  a# A<>void __fastcall TSuperPlayerform:RC(char &amp;S)
{
) Q& Y" {8 ~" K) l* F; H+ l  //char str;
  MCI_DGV_SETAUDIO_PARMS s;
  int err;
  char buf[1001];
/ ?5 {; c0 \0 n9 b  //str=''L'';
  if (MediaPlayer1-&gt;DeviceID&gt;0)
; M1 T6 a7 p/ Y9 s  {
    err=mciSendCommand(MediaPlayer1-&gt;DeviceID,MCI_SETAUDIO,MCI_SET_OFF,int(&amp;s));
    if (err!=0)
       mciGetErrorString(err,buf,sizeof(buf) );
    if (S=='C')
! r. ?3 i) p6 @) {1 V2 P) D* s       s.dwValue=MCI_DGV_SETAUDIO_SOURCE_STEREO;
/ y2 \* G3 ]+ d1 h; T. ?    if (S=='L')
* G" F1 P3 u: I2 E: v       s.dwValue=MCI_DGV_SETAUDIO_SOURCE_LEFT;
3 ]& a, J" c- X* M: A% ~4 a5 u8 E    if (S=='R') s.dwValue=MCI_DGV_SETAUDIO_SOURCE_RIGHT;
       s.dwItem=MCI_DGV_SETAUDIO_SOURCE;
, w+ P$ A# l9 O0 ?+ u- ]& C    const MCI_DGV_SETAUDIO_VALUE=0x01000000L;
* ?' s! p6 b' H$ t6 J- A2 `    const MCI_DGV_SETAUDIO_ITEM=0x00800000L;
    //(MCI_DGV_SETAUDIO_VALUE||MCI_DGV_SETAUDIO_ITEM)=0x01800000
    err=mciSendCommand(MediaPlayer1-&gt;DeviceID,MCI_SETAUDIO,0x01800000,int(&amp;s));
( F3 P5 N; U6 E    if (err!=0)
       mciGetErrorString(err,buf,sizeof(buf) );
    err=mciSendCommand(MediaPlayer1-&gt;DeviceID,MCI_SETAUDIO, MCI_SET_ON ,int(&amp;s));
$ \% e& g7 r7 u' B9 j( U    if (err!=0)
' z7 b. [6 n: t& F$ G: y6 R      mciGetErrorString(err,buf,sizeof(buf) );
+ U( p3 `. }& L   }
# n: @# k" ~6 l: u2 @8 j/ j }</P>
0 D9 d- k! E4 k" X<> void __fastcall TSuperPlayerform::popnosoundClick(TObject *Sender)
{
     LRC('L');
     Label3-&gt;Caption=“左声道 ";
     tempchannel='L';
}
//---------------------------------------------------------------------------</P>
<> void __fastcall TSuperPlayerform::popsoundClick(TObject *Sender)
2 Z$ C, P# Z1 v7 |/ z" {% z3 Q4 b {
     LRC('R');
  r: S( }, N4 Q1 r! h     Label3-&gt;Caption="右声道 ";
     tempchannel='R';
}
* p- Q1 C. B/ ]8 }: e3 Z, t//---------------------------------------------------------------------------</P>
<> void __fastcall TSuperPlayerform::steroClick(TObject *Sender)
! i$ o+ L$ V& C" c; L. |& Z# S, V {
8 d" b: A" L; O$ T7 t( D! u4 A     LRC('C');
     Label3-&gt;Caption="立体声 ";
+ g1 ^1 y1 K+ ]5 C, A& C1 o) E! h7 y6 W     tempchannel='C';
}</P>

ilikenba

<>左右声道的设置代码！从网上找到的！</P><>lReturn=mciSendString("set left off",sReturn,32,0)
0 `: j8 [) o  Q2 nlReturn=mciSendString("set right off",sReturn,32,0)
lReturn=mciSendString("setaudio left off",sReturn,32,0)
lReturn=mciSendString("setaudio right off",sReturn,32,0)
: K, `$ J+ L' l8 M& i* m确切地说，以上四句关闭的并不是左右声道，而是左右音箱。由于通常的多媒体音频流多是立体声的，并不是左音箱播放的完全是左声道的音频流，其中掺入轻微的右声道声音，以达到更好的立体效果。
+ S" q/ |0 R. i要想关闭左右声道可以这样：
7 u8 u: c# T/ qlReturn=mciSendString("setaudio source to left",sReturn,32,0) '仅开左声道
! y; m3 n& E- d; F* F: |  L3 I# elReturn=mciSendString("setaudio source to right",sReturn,32,0) '仅开右声道
lReturn=mciSendString("setaudio source to average",sReturn,32,0) '左右平均
; f. m2 y7 ]5 v8 p. ]# E9 NlReturn=mciSendString("setaudio source to stereo",sReturn,32,0) '立体声，这是默认设置</P>