Board index » delphi » Wav file format

2005-02-24 02:18:38 AM
delphi139
I get the following error when trying to play a .wav file "no wave device
that can play files in current format". Other wav files play fine. Are there
differences in wav formats and what type of "devices" are needed to play
them?
 

I am just guessing:
I know the basic structure of the *.wav header. The header allows *.wav to
have more then 2 channels (left and right). I never found a *.wav file with
more than 2 channels. But I wonder, what media player will do with such a
file on a familiar sound device, which supplies only 2 channels.
 

There are two types: Raw and compressed.
But 99.9% of aøø players support both types, especially if they call the
winapi or DirectShow to do the playing.
But more importantly than compression -is the wave sample format, and i get
the feeling this is your problem. I have a an expensive 24bit sound card for
harddisk recording, and it supports sampling at a wild range of frequencies.
If your card dont support the frequency the samples were recorded in - then
that would be the error message you get if you tried to play one of my wavs.
Most recordings exist in the 40 -/+ hz. area, but there are exceptions to
this rule.
Does it play in winamp or the standard windows player?
Try getting a wave-file editor and check out the samplerate and compression.
Kind regards
"George Kuasha" <XXXX@XXXXX.COM>writes

Check the header's contents of the wave file.
Here is the basic structure.
I do not know about compressions.
Const
WavePCM = 1;
type
{$IFDEF VER80}
LongWord = LongInt;
{$ENDIF}
{$IFDEF VER100}
LongWord = LongInt;
{$ENDIF}
tWaveHeader = packed Record
RiffID : Array[0 .. 3] of char; { 'RIFF' }
RiffLen : LongWord; { length of following data }
WaveID : Array[0 .. 3] of char; { 'WAVE' }
FmtID : Array[0 .. 3] of char; { 'fmt ' }
FmtLen : LongWord; { length of tFormat }
end;
tWaveFormat = packed Record
case Tag : Word of
WavePCM: (
PCMChannels : Word;
PCMSamplesPerSec : Word;
PCMAvgBytesPerSec : Word;
PCMBlockAlign : Word;
PCMUnKnown1 : Word;
PCMUnKnown2 : Word;
PCMBitsPerSample : Word;
PCMUnKnown3 : Array[1 .. 20] of Byte;
{ variable length } );
2: ( { and all other Tags }
OtherChannels : Word;
OtherSamplesPerSec : Word;
OtherAvgBytesPerSec : Word;
OtherBlockAlign : Word;
OtherUnKnown : Array[1 .. 20] of Byte;
{ variable length } );
end;
tWaveData = packed Record
ID : Array[0 .. 3] of char; { 'data' }
Len : LongWord; { length of following data }
end;
pWaveData = ^tWaveData;
tWaveBytes = Array[0 .. 0] of ShortInt;
tWaveWords = Array[0 .. 0] of SmallInt;
pWaveBytes = ^tWaveBytes;
pWaveWords = ^tWaveWords;
tWaveFile = Record
Header : tWaveHeader;
Format : tWaveFormat; { variable length }
{
Data : tWaveData;
left sample
right sample
left sample
right sample
...
}
end;
pWaveFile = ^tWaveFile;