如何判断一段avi的是多少侦？

Question

从视频采集卡上采集了一段视频保存成avi格式，如何知道这段视频是按每秒多少桢采集的呢？

Answer 1

unit UFm_Main;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ComCtrls, Buttons;function Hex(InChar:Char):String;Type TAVIMAINHEADER=Packed record
fcc:DWORD;
cb:DWORD;
dwMicroSecPerFrame:DWORD;
dwMaxBytesPerSec:DWORD;
dwPaddingGranularity:DWORD;
dwFlags:DWORD;
dwTotalFrames:DWORD;
dwInitialFrames:DWORD;
dwStreams:DWORD;
dwSuggestedBufferSize:DWORD;
dwWidth:DWORD;
dwHeight:DWORD;
dwReserved:array [0..3] of DWORD;
end;Type TAVISTREAMHEADER=Packed Record
fcc:DWORD;
cb:DWORD;
fccType:DWORD;
fccHandler:DWORD;
dwFlags:DWORD;
wPriority:DWORD;
wLanguage:DWORD;
dwInitialFrames:DWORD;
dwScale:DWORD;
dwRate:DWORD;
dwStart:DWORD;
dwLength:DWORD;
dwSuggestedBufferSize:DWORD;
dwQuality:DWORD;
dwSampleSize:DWORD;
left:ShortInt;
top:ShortInt;
right:ShortInt;
bottom:ShortInt;
end;type
  TFm_Main = class(TForm)
    BitBtn1: TBitBtn;
    RE_Info: TRichEdit;
    OD_AVI: TOpenDialog;
    procedure BitBtn1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;var
  Fm_Main: TFm_Main;
  AVIHeader:TAVIMAINHEADER;
  AVIStreamHeader:TAVISTREAMHEADER;implementation{$R *.dfm}
function DWToString(dwInput:DWORD):String;
begin
  Result:=Char(dwInput and $000000FF)
        +Char((dwInput shr 8) and $000000FF)
        +Char((dwInput shr 16) and $000000FF)
        +Char((dwInput shr 24) and $000000FF);
end;function GetAVIHeaderInfo():String;
var sTemp:String;
begin
  sTemp:='AVI Header Info:(64)*************************';
  sTemp:=sTemp+#13#10+'fcc:'+DWToString(AVIHeader.fcc);
  sTemp:=sTemp+#13#10+'cb:'+IntToStr(AVIHeader.cb);
  sTemp:=sTemp+#13#10+'dwMicroSecPerFrame:'+IntToStr(AVIHeader.dwMicroSecPerFrame);
  sTemp:=sTemp+#13#10+'dwMaxBytesPerSec:'+IntToStr(AVIHeader.dwMaxBytesPerSec);
  sTemp:=sTemp+#13#10+'dwPaddingGranularity:'+IntToStr(AVIHeader.dwPaddingGranularity);
  sTemp:=sTemp+#13#10+'dwFlags:'+IntToStr(AVIHeader.dwFlags);
  sTemp:=sTemp+#13#10+'dwTotalFrames:'+IntToStr(AVIHeader.dwTotalFrames);
  sTemp:=sTemp+#13#10+'dwInitialFrames:'+IntToStr(AVIHeader.dwInitialFrames);
  sTemp:=sTemp+#13#10+'dwStreams:'+IntToStr(AVIHeader.dwStreams);
  sTemp:=sTemp+#13#10+'dwSuggestedBufferSize:'+IntToStr(AVIHeader.dwSuggestedBufferSize);
  sTemp:=sTemp+#13#10+'dwWidth:'+IntToStr(AVIHeader.dwWidth);
  sTemp:=sTemp+#13#10+'dwHeight:'+IntToStr(AVIHeader.dwHeight);
  sTemp:=sTemp+#13#10+'dwReserved:'+IntToStr(AVIHeader.dwReserved[0])
                               +','+IntToStr(AVIHeader.dwReserved[1])
                               +','+IntToStr(AVIHeader.dwReserved[2])
                               +','+IntToStr(AVIHeader.dwReserved[3]);
  sTemp:=sTemp+#13#10+'AVI Header Info:(64)*************************';
  Result:=sTemp;
end;function GetAVIStreamHeaderInfo():String;
var sTemp:String;
begin
  sTemp:='AVI Stream Header Info:(64)***********************';
  sTemp:=sTemp+#13#10+'fcc:'+DWToString(AVIStreamHeader.fcc);
  sTemp:=sTemp+#13#10+'cb:'+IntToStr(AVIStreamHeader.cb);
  sTemp:=sTemp+#13#10+'fccType:'+IntToStr(AVIStreamHeader.fccType);
  sTemp:=sTemp+#13#10+'fccHandle:'+IntToStr(AVIStreamHeader.fccHandler);
  sTemp:=sTemp+#13#10+'dwFlags:'+IntToStr(AVIStreamHeader.dwFlags);
  sTemp:=sTemp+#13#10+'wPriority:'+IntToStr(AVIStreamHeader.wPriority);
  sTemp:=sTemp+#13#10+'wLanguage:'+IntToStr(AVIStreamHeader.wLanguage);
  sTemp:=sTemp+#13#10+'dwInitialFrames:'+IntToStr(AVIStreamHeader.dwInitialFrames);
  sTemp:=sTemp+#13#10+'dwScale:'+IntToStr(AVIStreamHeader.dwScale);
  sTemp:=sTemp+#13#10+'dwRate:'+IntToStr(AVIStreamHeader.dwRate);
  sTemp:=sTemp+#13#10+'dwStart:'+IntToStr(AVIStreamHeader.dwStart);
  sTemp:=sTemp+#13#10+'dwLength:'+IntToStr(AVIStreamHeader.dwLength);
  sTemp:=sTemp+#13#10+'dwSuggestedBufferSize:'+IntToStr(AVIStreamHeader.dwSuggestedBufferSize);
  sTemp:=sTemp+#13#10+'dwSampleSize:'+IntToStr(AVIStreamHeader.dwSampleSize);
  sTemp:=sTemp+#13#10+'Left:'+IntToStr(AVIStreamHeader.left);
  sTemp:=sTemp+#13#10+'Top:'+IntToStr(AVIStreamHeader.top);
  sTemp:=sTemp+#13#10+'Right:'+IntToStr(AVIStreamHeader.right);
  sTemp:=sTemp+#13#10+'Bottom:'+IntToStr(AVIStreamHeader.bottom);
  sTemp:=sTemp+#13#10+'AVI Stream Header Info:(64)*************************';
  Result:=sTemp;
end;

Answer 2

procedure TFm_Main.BitBtn1Click(Sender: TObject);
var
  iFileHandle: Integer;
  Buf: PChar;
  BufSize:DWORD;
  ChunkSize:DWORD;
  i,j,k:Integer;
  seqCount:Integer;
  sTemp:String;
  F: TextFile;
  SubCodePos:Integer;
  iDay,iMonth,iYear,iSec,iMin,iHour:Integer;
begin
  if not OD_AVI.Execute then Exit;
  iFileHandle := FileOpen(OD_AVI.FileName, fmOpenRead+fmShareDenyNone);
  //AVI文件关头信息
  BufSize:=4;
  Buf := PChar(AllocMem(BufSize + 1));
  sTemp:='';
  repeat
    FileRead(iFileHandle, Buf^, BufSize);
    sTemp:=Buf[0]+Buf[1]+Buf[2]+Buf[3];
  until sTemp='hdrl';
  FreeMem(Buf);
  FileRead(iFileHandle, AVIHeader, SizeOf(TAVIMAINHEADER));
  RE_Info.Lines.Add(GetAVIHeaderInfo());  //AVI文件流信
  BufSize:=4;
  Buf := PChar(AllocMem(BufSize + 1));
  sTemp:='';
  repeat
    FileRead(iFileHandle, Buf^, BufSize);
    sTemp:=Buf[0]+Buf[1]+Buf[2]+Buf[3];
  until sTemp='strl';
  FreeMem(Buf);
  FileRead(iFileHandle, AVIStreamHeader, SizeOf(TAVISTREAMHEADER));
  RE_Info.Lines.Add(GetAVIStreamHeaderInfo());  //找到AVI文件电影片段开始处
  BufSize:=4;
  Buf := PChar(AllocMem(BufSize + 1));
  sTemp:='';
  repeat
    FileRead(iFileHandle, Buf^, BufSize);
    sTemp:=Buf[0]+Buf[1]+Buf[2]+Buf[3];
  until sTemp='movi';
  FreeMem(Buf);  //开始处理帧
  BufSize:=4;
  Buf := PChar(AllocMem(BufSize + 1));
  sTemp:='';
  repeat
    FileRead(iFileHandle, Buf^, BufSize);
    sTemp:=Buf[0]+Buf[1]+Buf[2]+Buf[3];
  until sTemp='00db';
  //取段大小
  FileRead(iFileHandle, ChunkSize, BufSize);
  FreeMem(Buf);
  BufSize:=ChunkSize;
  Buf := PChar(AllocMem(BufSize + 1));
  FileRead(iFileHandle, Buf^, BufSize);  seqCount := 12;
  //  /* process all DIF sequences */
  for i:=0 to seqCount-1 do begin
    //* there are two DIF blocks in the subcode section */
    for j:=0 to 1 do begin
      //* each block has 6 packets */
      for k:=0 to 5 do begin
        {/* calculate address: 150 DIF blocks per sequence, 80 bytes
           per DIF block, subcode blocks start at block 1, block and
           packet have 3 bytes header, packet is 8 bytes long
           (including header) */}
         SubCodePos:=i * 150 * 80 + 1 * 80 + j * 80 + 3 + k * 8 + 3;
         if Hex(Buf[SubCodePos])='62' then begin//年月日
           iDay:=Ord(Buf[SubCodePos+2]);
           iMonth:=Ord(Buf[SubCodePos+3]);
           iYear:=Ord(Buf[SubCodePos+4]);
           iDay:=(iDay and $F)+10*((iDay shr 4) and $3);
           iMonth:=(iMonth and $F)+10*((iMonth shr 4) and $1);
           iYear:=(iYear and $F)+10*((iYear shr 4) and $F);
           if iYear<25 then
             iYear:=iYear+2000
           else
             iYear:=iYear+1900;
           RE_Info.Lines.Add(Hex(Buf[SubCodePos])+' '
                            +Hex(Buf[SubCodePos+1])+' '
                            +Hex(Buf[SubCodePos+2])+' '
                            +Hex(Buf[SubCodePos+3])+' '
                            +Hex(Buf[SubCodePos+4]));
           RE_Info.Lines.Add('Date:'+IntToStr(iYear)+'-'
                                    +IntToStr(iMonth)+'-'
                                    +IntToStr(iDay));
         end;
         if Hex(Buf[SubCodePos])='63' then begin//秒分时
           iSec:=Ord(Buf[SubCodePos+2]);
           iMin:=Ord(Buf[SubCodePos+3]);
           iHour:=Ord(Buf[SubCodePos+4]);
           iSec:=(iSec and $F)+10*((iSec shr 4) and $7);
           iMin:=(iMin and $F)+10*((iMin shr 4) and $7);
           iHour:=(iHour and $F)+10*((iHour shr 4) and $3);
           RE_Info.Lines.Add(Hex(Buf[SubCodePos])+' '
                            +Hex(Buf[SubCodePos+1])+' '
                            +Hex(Buf[SubCodePos+2])+' '
                            +Hex(Buf[SubCodePos+3])+' '
                            +Hex(Buf[SubCodePos+4]));
           RE_Info.Lines.Add('Time:'+IntToStr(iHour)+':'
                                    +IntToStr(iMin)+':'
                                    +IntToStr(iSec));
         end;
      end;//end for k
    end;//end for j
  end;//end for i  AssignFile(F, 'OffSet.txt');
  FileMode:=fmOpenReadWrite ;
  Reset(F);
  Append(F);
  //for i:=0 to BufSize-1 do
  //  WriteLn(F,IntToHex(Ord(Buf[i]),2));
  CloseFile(F);  FreeMem(Buf);  FileClose(iFileHandle);
end;function Hex(InChar:Char):String;
begin
  Result:=IntToHex(Ord(InChar),2);
end;end.

Answer 3

实际上它的信息是在头内
00000000 RIFF (103E2920) 'AVI '
0000000C     LIST (00000146) 'hdrl'
00000018         avih (00000038)
                     dwMicroSecPerFrame    : 33367
                     dwMaxBytesPerSec      : 3728000
                     dwPaddingGranularity  : 0
                     dwFlags               : 0x810 HASINDEX | TRUSTCKTYPE
                     dwTotalFrames         : 2192
                     dwInitialFrames       : 0
                     dwStreams             : 2
                     dwSuggestedBufferSize : 120000
                     dwWidth               : 720
                     dwHeight              : 480
                     dwReserved            : 0x0
00000058         LIST (00000094) 'strl'
00000064             strh (00000038)
                         fccType               : 'vids'
                         fccHandler            : 'dvsd'
                         dwFlags               : 0x0
                         wPriority             : 0
                         wLanguage             : 0x0 undefined
                         dwInitialFrames       : 0
                         dwScale               : 100 (29.970 Frames/Sec)
                         dwRate                : 2997
                         dwStart               : 0
                         dwLength              : 2192
                         dwSuggestedBufferSize : 120000
                         dwQuality             : 0
                         dwSampleSize          : 0
                         rcFrame               : 0,0,720,480
000000A4             strf (00000048)
                         biSize          : 40
                         biWidth         : 720
                         biHeight        : 480
                         biPlanes        : 1
                         biBitCount      : 24
                         biCompression   : 0x64737664 'dvsd'
                         biSizeImage     : 120000
                         biXPelsPerMeter : 0
                         biYPelsPerMeter : 0
                         biClrUsed       : 0
                         biClrImportant  : 0
                         dwDVAAuxSrc     : 0x........
                         dwDVAAuxCtl     : 0x........
                         dwDVAAuxSrc1    : 0x........
                         dwDVAAuxCtl1    : 0x........
                         dwDVVAuxSrc     : 0x........
                         dwDVVAuxCtl     : 0x........
                         dwDVReserved[2] : 0,0
000000F4         LIST (0000005E) 'strl'
00000100             strh (00000038)
                         fccType               : 'auds'
                         fccHandler            : '    '
                         dwFlags               : 0x0
                         wPriority             : 0
                         wLanguage             : 0x0 undefined
                         dwInitialFrames       : 0
                         dwScale               : 1 (32000.000 Samples/Sec)
                         dwRate                : 32000
                         dwStart               : 0
                         dwLength              : 2340474
                         dwSuggestedBufferSize : 4272
                         dwQuality             : 0
                         dwSampleSize          : 4
                         rcFrame               : 0,0,0,0
00000140             strf (00000012)
                         wFormatTag      : 1 PCM
                         nChannels       : 2
                         nSamplesPerSec  : 32000
                         nAvgBytesPerSec : 128000
                         nBlockAlign     : 4
                         wBitsPerSample  : 16
                         cbSize          : 0
00000814     LIST (103D0EF4) 'movi'
103D1710     idx1 (00011210)

Answer 4

你只要看取AVI头的部分就行了，其它是用来取拍摄时间的，还没完全写完

Answer 5

说明一下，拍摄时间只针对采集的DV AVI有效

Answer 6

谢谢，你belllab，不过如果是mpg4文件呢？可以再开个帖子给你分。谢谢！

Answer 7

mpeg我倒还没有研究过，我研究AVI是因为我想从DV中取拍摄时间，估计MPEG也应该有相关的资料吧

Answer 8

如果只是要mpg4的帧数的话，你看一下他的文件头，应该有的