|
unit uVoxToWave;
interface
uses
SysUtils;
type
TVoxFormat = (VF_ADPCM = 1, VF_MULAW = 2, VF_ALAW = 3);
TVoxRate = (VR_6K = 6000, VR_8K = 8000);
TVoxBitsPerSample = (VB_8 = 1, VB_16 = 2);
TWaveHead = packed record
cHead: array[0..3] of char; {'RIFF'}
nLength: longint;
cWaveTag: array[0..7] of char; {'WAVEfmt '}
nHeaderLength: LongInt; {16}
wFormatTag: Word; { format type 01 00}
nChannels: Word; { number of channels (i.e. mono, stereo, etc.) 01}
nSamplesPerSec: longint; { sample rate 8000}
nAvgBytesPerSec: longint; { for buffer estimation 8000}
nBlockAlign: Word; {1}
wBitsPerSample: word; {8}
end;
TDataHead = packed record
cDataTag: array[0..3] of char; {'data'}
nDatalen: longint;
end;
PWaveHead = ^TWaveHead;
TVox = class
private
FInFileName, FOutFileName: string;
FVoxFormat: TVoxFormat;
FVoxRate: TVoxRate;
FVoxBitsPerSample: TVoxBitsPerSample;
rate, bit_rate: integer;
sample: byte; // sample read from input file
buffer: array[0..9999] of byte; // a block of input data
SS: Word; // current step size for ADPCM
SSindex: Word; // current index into step size table
Sn: Smallint; // current 12-bit linear sample value
out_val: byte; // .WAV output value
out_int: Smallint; // linear output value
function decode(sample: byte; Sn: SmallInt; var SS: WORD; var SSindex: WORD): smallint;
procedure ConvertADPCM(infile, outfile: integer);
procedure ConvertMULAW(infile, outfile: integer);
procedure ConvertALAW(infile, outfile: integer);
published
property InFileName: string read FInFileName;
property OutFileName: string read FOutFileName;
public
constructor Create(InFileName: string; OutFileName: string = ''; VoxFormat: TVoxFormat = VF_ADPCM; VoxRate: TVoxRate = VR_6K; VoxBitsPerSample: TVoxBitsPerSample = VB_8);
function Convert: integer;
end;
const
SEEK_SET = 0;
SEEK_END = 2;
ResetValue = 48;
formats: array[0..2] of string = ('ADPCM', 'Mu-Law', 'A-Law');
mulaw: array[0..255] of smallint = (
-32124, -31100, -30076, -29052, -28028, -27004, -25980, -24956,
-23932, -22908, -21884, -20860, -19836, -18812, -17788, -16764,
-15996, -15484, -14972, -14460, -13948, -13436, -12924, -12412,
-11900, -11388, -10876, -10364, -9852, -9340, -8828, -8316,
-7932, -7676, -7420, -7164, -6908, -6652, -6396, -6140,
-5884, -5628, -5372, -5116, -4860, -4604, -4348, -4092,
-3900, -3772, -3644, -3516, -3388, -3260, -3132, -3004,
-2876, -2748, -2620, -2492, -2364, -2236, -2108, -1980,
-1884, -1820, -1756, -1692, -1628, -1564, -1500, -1436,
-1372, -1308, -1244, -1180, -1116, -1052, -988, -924,
-876, -844, -812, -780, -748, -716, -684, -652,
-620, -588, -556, -524, -492, -460, -428, -396,
-372, -356, -340, -324, -308, -292, -276, -260,
-244, -228, -212, -196, -180, -164, -148, -132,
-120, -112, -104, -96, -88, -80, -72, -64,
-56, -48, -40, -32, -24, -16, -8, 0,
32124, 31100, 30076, 29052, 28028, 27004, 25980, 24956,
23932, 22908, 21884, 20860, 19836, 18812, 17788, 16764,
15996, 15484, 14972, 14460, 13948, 13436, 12924, 12412,
11900, 11388, 10876, 10364, 9852, 9340, 8828, 8316,
7932, 7676, 7420, 7164, 6908, 6652, 6396, 6140,
5884, 5628, 5372, 5116, 4860, 4604, 4348, 4092,
3900, 3772, 3644, 3516, 3388, 3260, 3132, 3004,
2876, 2748, 2620, 2492, 2364, 2236, 2108, 1980,
1884, 1820, 1756, 1692, 1628, 1564, 1500, 1436,
1372, 1308, 1244, 1180, 1116, 1052, 988, 924,
876, 844, 812, 780, 748, 716, 684, 652,
620, 588, 556, 524, 492, 460, 428, 396,
372, 356, 340, 324, 308, 292, 276, 260,
244, 228, 212, 196, 180, 164, 148, 132,
120, 112, 104, 96, 88, 80, 72, 64,
56, 48, 40, 32, 24, 16, 8, 0
);
alaw: array[0..255] of smallint = (
-5504, -5248, -6016, -5760, -4480, -4224, -4992, -4736,
-7552, -7296, -8064, -7808, -6528, -6272, -7040, -6784,
-2752, -2624, -3008, -2880, -2240, -2112, -2496, -2368,
-3776, -3648, -4032, -3904, -3264, -3136, -3520, -3392,
-22016, -20992, -24064, -23040, -17920, -16896, -19968, -18944,
-30208, -29184, -32256, -31232, -26112, -25088, -28160, -27136,
-11008, -10496, -12032, -11520, -8960, -8448, -9984, -9472,
-15104, -14592, -16128, -15616, -13056, -12544, -14080, -13568,
-344, -328, -376, -360, -280, -264, -312, -296,
-472, -456, -504, -488, -408, -392, -440, -424,
-88, -72, -120, -104, -24, -8, -56, -40,
-216, -200, -248, -232, -152, -136, -184, -168,
-1376, -1312, -1504, -1440, -1120, -1056, -1248, -1184,
-1888, -1824, -2016, -1952, -1632, -1568, -1760, -1696,
-688, -656, -752, -720, -560, -528, -624, -592,
-944, -912, -1008, -976, -816, -784, -880, -848,
5504, 5248, 6016, 5760, 4480, 4224, 4992, 4736,
7552, 7296, 8064, 7808, 6528, 6272, 7040, 6784,
2752, 2624, 3008, 2880, 2240, 2112, 2496, 2368,
3776, 3648, 4032, 3904, 3264, 3136, 3520, 3392,
22016, 20992, 24064, 23040, 17920, 16896, 19968, 18944,
30208, 29184, 32256, 31232, 26112, 25088, 28160, 27136,
11008, 10496, 12032, 11520, 8960, 8448, 9984, 9472,
15104, 14592, 16128, 15616, 13056, 12544, 14080, 13568,
344, 328, 376, 360, 280, 264, 312, 296,
472, 456, 504, 488, 408, 392, 440, 424,
88, 72, 120, 104, 24, 8, 56, 40,
216, 200, 248, 232, 152, 136, 184, 168,
1376, 1312, 1504, 1440, 1120, 1056, 1248, 1184,
1888, 1824, 2016, 1952, 1632, 1568, 1760, 1696,
688, 656, 752, 720, 560, 528, 624, 592,
944, 912, 1008, 976, 816, 784, 880, 848
);
// stepsize adjustments per Dialogic Application Note 1366
SSadjust: array[0..7] of smallint = (-1, -1, -1, -1, 2, 4, 6, 8);
// Calculated stepsizes per Dialogic Application Note 1366
SStable: array[0..49] of smallint = (0, 16, 17, 19, 21, 23, 25, 28, 31,
34, 37, 41, 45, 50, 55, 60, 66, 73,
80, 88, 97, 107, 118, 130, 143, 157, 173,
190, 209, 230, 253, 279, 307, 337, 371, 408,
449, 494, 544, 598, 658, 724, 796, 876, 963,
1060, 1166, 1282, 1411, 1552);
implementation
constructor TVox.Create(InFileName: string; OutFileName: string = ''; VoxFormat: TVoxFormat = VF_ADPCM; VoxRate: TVoxRate = VR_6K; VoxBitsPerSample: TVoxBitsPerSample = VB_8);
begin
FInFileName := Trim(InFileName);
FOutFileName := Trim(OutFileName);
FVoxFormat := VoxFormat;
FVoxRate := VoxRate;
FVoxBitsPerSample := VoxBitsPerSample;
if (FOutFileName = '') then
FOutFileName := ChangeFileExt(FInFileName, '.wav');
rate := Integer(FVoxRate);
bit_rate := Integer(FVoxBitsPerSample);
end;
function TVox.decode(sample: byte; Sn: SmallInt; var SS: WORD; var SSindex: WORD): smallint;
var
Mn: SmallInt;
begin
//转换公式如下
//d(n) = (ss(n)*B2)+(ss(n)/2*B1)+(ss(n)/4*BO)+(ss(n)/8)
//if (B3 = 1)
//then d(n) = d(n) * (-1)
//X(n) = X(n-1) + d(n)
Mn := 0; // calculate the linear adjustment
if (sample and $4) <> 0 then Mn := SS;
if (sample and $2) <> 0 then Mn := Mn + (SS shr 1); //div 2
if (sample and $1) <> 0 then Mn := Mn + (SS shr 2); //div 4
Mn := Mn + (SS shr 3); //div 8
//取Sample的符号位，即最高位
if (sample and $8) <> 0 then //最高位为1，则符号位为负
Sn := Sn - Mn // ...subtract the adjustment
else // 符号位为正
Sn := Sn + Mn; // ...add the adjustment
if (Sn > 2047) then // adjust if sample too large...
Sn := 2047;
if (Sn < -2048) then // ...or too small
Sn := -2048;
// use as index into step size adjustment, adjust step size index
SSindex := SSIndex + SSadjust[sample and $7];
if (SSindex < 1) then // keep SSindex within bounds...
SSindex := 1;
if (SSindex > 49) then
SSindex := 49;
SS := SStable[SSindex]; // get new step size from table
Result := Sn;
end;
//----- Dialogc VOX语音格式说明，以6K/8Bits示例-----------------------------------------------------
//一个字节中包含两个SAMPLE，7-4位为Sample N,3-0位为Sample N+1
//每一个Sample都是以ADPCM(Adaptive Differential Pulse Code Modulation)
//进行编码，每4位(3,2,1,0)构成的Sample中，其中第3位为符号位 0-正 1-负，2-0位相对前一个Sample的变化量
//出现48个二进制的1000或0000，则需要复位ADPCM算法初始值
//---------------------------------------------------------------------------------------------------
procedure TVox.ConvertADPCM(infile, outfile: integer);
var
index: Integer; // index for misc. arrays
bytes: Integer; // number of bytes read into a buffer
outindex: Integer; //index for output arrays
outbytebuffer: array[0..19999] of byte; //output buffer
outintbuffer: array[0..19999] of Smallint; //output buffer
i: integer;//Reset Count
HighByte,LowByte:Byte;
begin
Sn := 0; // initialize the ADPCM variables
SS := 16; // initialize the Step
SSindex := 1;
i := 0;
// read a byte of ADPCM data
bytes := FileRead(infile, buffer, 10000);
while (bytes > 0) do
begin
outindex := 0;
for index := 0 to (bytes - 1) do
begin
sample := buffer[index];
HighByte := sample shr 4;
LowByte := sample and $F;
if (HighByte =0) or (HighByte=8) then
inc(i);
// 先解压缩一个字节中的高4位...
Sn := decode(WORD(sample shr 4), Sn, SS, SSindex);
if (bit_rate = 1) then // if 8 bits per sample...
begin
out_int := Sn shr 4; // rescale output from -128 thru 127
if (out_int > 127) then // clip if above or below WAV bounds
out_int := 127;
if (out_int < -128) then
out_int := -128;
out_val := byte(out_int - 128); // convert to .WAV format
outbytebuffer[outindex] := out_val; // write the output byte
Inc(outindex);
end
else
begin
out_int := Sn shl 4; // rescale to 16 bits
outintbuffer[outindex] := out_int; // write the output int
Inc(outindex);
end;
if i = ResetValue then //Reset ADPCM variables
begin
Sn := 0; // initialize the ADPCM variables
SS := 16; // initialize the Step
i := 0;
end;
if (LowByte=0) or (LowByte=8) then
inc(i);
// now decode the low nibble...
Sn := decode(WORD(sample and $F), Sn, SS, SSindex);
if (bit_rate = 1) then // if 8 bits per sample...
begin
out_int := Sn shr 4; // rescale output from -128 thru 127
if (out_int > 127) then // clip if above or below WAV bounds
out_int := 127;
if (out_int < -128) then
out_int := -128;
out_val := out_int - 128; // convert to .WAV format
outbytebuffer[outindex] := out_val; // write the output byte
Inc(outindex);
end
else
begin
out_int := Sn shl 4; // rescale to 16 bits
outintbuffer[outindex] := out_int; // write the output int
Inc(outindex);
end;
if i = ResetValue then //Reset ADPCM variables
begin
Sn := 0; // initialize the ADPCM variables
SS := 16; // initialize the Step
i := 0;
end;
end;
if (bit_rate = 1) then
FileWrite(outfile, outbytebuffer, bytes * 2)
else
FileWrite(outfile, outintbuffer, bytes * 4);
bytes := FileRead(infile, buffer, 10000);
end;
end;
procedure TVox.ConvertMULAW(infile, outfile: integer);
var
index: Integer; // index for misc. arrays
bytes: Integer; // number of bytes read into a buffer
outindex: Integer; //index for output arrays
outbytebuffer: array[0..19999] of byte; //output buffer
outintbuffer: array[0..19999] of SmallInt; //output buffer
begin
// read a block of mu-law data
bytes := FileRead(infile, buffer, 10000);
while (bytes > 0) do
begin
outindex := 0;
for index := 0 to bytes - 1 do
begin
out_int := mulaw[buffer[index]]; // convert mu-law to linear
if (bit_rate = 1) then // if 8 bits per sample...
begin
out_int := out_int shr 8; // rescale for 8 bit values
out_val := out_int + 128; // convert to .WAV format
outbytebuffer[outindex] := out_val; // write the output byte
Inc(outindex);
end
else
begin
outintbuffer[outindex] := out_int; // write the output int
Inc(outindex);
end;
end;
if (bit_rate = 1) then
FileWrite(outfile, outbytebuffer, bytes * 2)
else
FileWrite(outfile, outintbuffer, bytes * 4);
bytes := FileRead(infile, buffer, 10000);
end;
end;
procedure TVox.ConvertALAW(infile, outfile: integer);
var
index: Integer; // index for misc. arrays
bytes: Integer; // number of bytes read into a buffer
outindex: Integer; //index for output arrays
outbytebuffer: array[0..19999] of byte; //output buffer
outintbuffer: array[0..19999] of Smallint; //output buffer
begin
// read a block of a-law data
bytes := FileRead(infile, buffer, 10000);
while (bytes > 0) do
begin
outindex := 0;
for index := 0 to bytes - 1 do
begin
out_int := alaw[buffer[index]]; // convert a-law to linear
if (bit_rate = 1) then // if 8 bits per sample...
begin
out_int := out_int shr 8; // rescale for WAV file
out_val := out_int + 128; // convert to .WAV format
outbytebuffer[outindex] := out_val; // write the output byte
Inc(outindex);
end
else
begin
outintbuffer[outindex] := out_int; // write the output int
Inc(outindex);
end;
end;
if (bit_rate = 1) then
FileWrite(outfile, outbytebuffer, bytes * 2)
else
FileWrite(outfile, outintbuffer, bytes * 4);
bytes := FileRead(infile, buffer, 10000);
end;
end;
function TVox.Convert: integer;
var
infile, outfile, filesize: Integer;
WaveHead: TWaveHead;
DataHead: TDataHead;
begin
infile := FileOpen(FInFileName, $0040);
if (infile <= 0) then //If can't create Input File...
begin
Result := -2;
exit;
end;
outfile := FileCreate(FOutFileName);
if (outfile <= 0) then // If can't create Output File....
begin
FileClose(infile); //close Input File
Result := -3;
exit;
end;
filesize := FileSeek(infile, 0, SEEK_END); //get size of input file
if (FVoxFormat = VF_ADPCM) then // if using ADPCM input format...
filesize := filesize * 2; // change from bytes to samples
FileSeek(infile, 0, SEEK_SET); // seek back to beginning of input
//---------Create Wave File Head ---------------------------------------------
StrCopy(WaveHead.cHead, 'RIFF'); // .WAV begins with "RIFF"
WaveHead.nLength := (filesize * bit_rate) + sizeof(TWaveHead); // size of .WAV file (data+header)
StrCopy(WaveHead.cWaveTag, 'WAVEfmt ');
WaveHead.nHeaderLength := 16; // size of .WAV file header
WaveHead.wFormatTag := 1; // format tag (01 = Windows PCM)
WaveHead.nChannels := 1; // channels (1=mono, 2=stereo)
WaveHead.nSamplesPerSec := rate; // samples per second
WaveHead.nAvgBytesPerSec := rate * bit_rate; // bytes per second during play
WaveHead.nBlockAlign := bit_rate; // bytes per sample
WaveHead.wBitsPerSample := 8 * bit_rate; // bits per sample
StrCopy(DataHead.cDataTag, 'data'); // specify "data" follows
DataHead.nDatalen := filesize * bit_rate; // write size of .WAV data portion
FileWrite(outfile, WaveHead, sizeof(TWaveHead));
FileWrite(outfile, DataHead, sizeof(TDataHead));
case FVoxFormat of
VF_ADPCM: ConvertADPCM(infile, outfile);
VF_MULAW: ConvertMULAW(infile, outfile);
VF_ALAW: ConvertALAW(infile, outfile);
end;
FileClose(infile);
FileClose(outfile);
Result := 0;
end;
end.
|
客服电话
APP下载
官方微信
请发表评论