portaudio Pa_ReadStream and Pa_WriteStream的使用

使用portaudio 使用Pa_ReadStream and Pa_WriteStream，如下
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#include <stdio.h>
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#include <stdlib.h>
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#include "portaudio.h"
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/* #define SAMPLE_RATE (17932) /* Test failure to open with this value. */
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#define SAMPLE_RATE (44100)
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#define FRAMES_PER_BUFFER (1024)
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#define NUM_SECONDS (5)
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#define NUM_CHANNELS (2)
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/* #define DITHER_FLAG (paDitherOff) */
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#define DITHER_FLAG (0) /**/
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/* Select sample format. */
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#if 1
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#define PA_SAMPLE_TYPE paFloat32
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typedef float SAMPLE;
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#define SAMPLE_SILENCE (0.0f)
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#define PRINTF_S_FORMAT "%.8f"
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#elif 1
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#define PA_SAMPLE_TYPE paInt16
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typedef short SAMPLE;
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#define SAMPLE_SILENCE (0)
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#define PRINTF_S_FORMAT "%d"
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#elif 0
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#define PA_SAMPLE_TYPE paInt8
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typedef char SAMPLE;
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#define SAMPLE_SILENCE (0)
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#define PRINTF_S_FORMAT "%d"
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#else
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#define PA_SAMPLE_TYPE paUInt8
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typedef unsigned char SAMPLE;
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#define SAMPLE_SILENCE (128)
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#define PRINTF_S_FORMAT "%d"
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#endif
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#define FORMATID "fmt "
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#define DATAID "data"
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typedef struct {
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char chunkID[4];
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long chunkSize;
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short wFormatTag;
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unsigned short wChannels;
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unsigned long dwSamplesPerSec;
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unsigned long dwAvgBytesPerSec;
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unsigned short wBlockAlign;
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unsigned short wBitsPerSample;
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} FormatChunk;
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typedef struct {
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char chunkID[4];
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long chunkSize;
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} DataChunkHeader;
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int checkHeader(FILE *fid) {
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char riff[4];
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char wave[4];
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fread(riff, 4, sizeof(char), fid);
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/* throwaway 4 bytes */
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fread(wave, 4, sizeof(char), fid);
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fread(wave, 4, sizeof(char), fid);
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if (!((strncmp(riff, "RIFF", 4) == 0) &&
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(strncmp(wave, "WAVE", 4) == 0))) {
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return -1;
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}
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return 0;
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}
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int getData(FILE *fid, char **data) {
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DataChunkHeader dch;
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while (strncmp(dch.chunkID, DATAID, 4) != 0) {
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fread(&dch, sizeof(DataChunkHeader), 1, fid);
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if (feof(fid) || ferror(fid))
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return -1;
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}
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printf("Size of data: %d\n", dch.chunkSize);
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*data = (char *) malloc ( dch.chunkSize * sizeof(char) );
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fread(*data, sizeof(char), dch.chunkSize, fid);
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if (feof(fid) || ferror(fid)) {
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free(data);
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return -1;
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}
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return dch.chunkSize;
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}
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int getFormatChunk(FILE *fid, FormatChunk *formatChunk) {
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while (strncmp(formatChunk->chunkID, FORMATID, 4) != 0) {
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fread(formatChunk, sizeof(FormatChunk), 1, fid);
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if (feof(fid) || ferror(fid))
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return -1;
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}
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return 0;
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}
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/*******************************************************************/
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int main(int argc, char *argv[])
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{
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PaStreamParameters outputParameters;
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PaStream *stream;
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PaError err;
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/*int i;
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int totalFrames;
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int numSamples;
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int numBytes;
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*/
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/* read wave file */
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char *filename;
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FILE *fid;
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if (argc < 2) {
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printf("Usage: %s filename.wav\n", argv[0]);
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return -1;
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}
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/* filename */
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filename = argv[1];
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printf("Filename: %s\n", filename);
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/* open file */
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fid = fopen(filename, "rb");
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if (fid == NULL) {
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printf("Could not open file %s\n", filename);
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return -1;
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}
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/* check header */
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if (checkHeader(fid) < 0) {
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printf("Not a wave file!\n");
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return -1;
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}
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FormatChunk formatChunk;
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int data_size;
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char *data;
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if (getFormatChunk(fid, &formatChunk) < 0) {
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printf("Couldn't read header\n");
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return -1;
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}
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printf("Chunk Size : %d\n", formatChunk.chunkSize);
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printf("Compressed : %d\n", formatChunk.wFormatTag != 1);
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printf("Channels : %d\n", formatChunk.wChannels);
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printf("SamplesPerSecond : %d\n", formatChunk.dwSamplesPerSec);
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printf("dwAvgBytesPerSec : %d\n", formatChunk.dwAvgBytesPerSec);
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printf("wBlockAlign : %d\n", formatChunk.wBlockAlign);
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printf("wBitsPerSample : %d\n", formatChunk.wBitsPerSample);
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if ((data_size = getData(fid, &data)) < 0) {
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printf("Couldn't read data\n");
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return -1;
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}
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int total_frames = data_size / formatChunk.wBlockAlign;
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printf("Total Frames : %d\n", total_frames);
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/* fclose(fid); */
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err = Pa_Initialize();
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if( err != paNoError ) goto error;
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/* Playback recorded data. -------------------------------------------- */
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outputParameters.device = Pa_GetDefaultOutputDevice(); /* default output device */
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outputParameters.channelCount = formatChunk.wChannels;
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outputParameters.sampleFormat = paInt16;
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outputParameters.suggestedLatency = Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency;
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printf("YO YO\n"); fflush(stdout);
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outputParameters.hostApiSpecificStreamInfo = NULL;
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printf("Begin playback.\n"); fflush(stdout);
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err = Pa_OpenStream(
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&stream,
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NULL, /* no input */
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&outputParameters,
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formatChunk.dwSamplesPerSec,
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0, /*FRAMES_PER_BUFFER, */
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paClipOff, /* we won't output out of range samples so don't bother clipping them */
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NULL, /* no callback, use blocking API */
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NULL ); /* no callback, so no callback userData */
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if( err != paNoError ) goto error;
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if( stream )
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{
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err = Pa_StartStream( stream );
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if( err != paNoError ) goto error;
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printf("Waiting for playback to finish.\n"); fflush(stdout);
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err = Pa_WriteStream( stream, data, total_frames );
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if( err != paNoError ) goto error;
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err = Pa_CloseStream( stream );
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if( err != paNoError ) goto error;
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printf("Done.\n"); fflush(stdout);
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}
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free( data );
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Pa_Terminate();
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return 0;
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error:
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Pa_Terminate();
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fprintf( stderr, "An error occured while using the portaudio stream\n" );
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fprintf( stderr, "Error number: %d\n", err );
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fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
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return -1;
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}