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// rresample.h #ifndef __RRESAMPLE_H_ #define __RRESAMPLE_H_ int init_PCM_resample(int output_channels, int input_channels, int output_rate, int input_rate); int start_PCM_resample(short *output, short *input, int in_len); int uninit_PCM_resample(); int bit_wide_transform(int flag,int in_len,unsigned char* in_buf,unsigned char* out_buf); int volume_control(short* out_buf,short* in_buf,int in_len, float in_vol); #endif //========================================================================//rresample.c #include "rresample.h" #include <math.h> #include <stdlib.h> #include <stdio.h> #include <string.h> #define FRAC_BITS 16 #define FRAC (1 << FRAC_BITS) #define av_free(p) {if(p) free(p);} #define av_malloc(size) malloc(size) #define UINT unsigned int typedef struct { /* fractional resampling */ UINT incr; /* fractional increment */ UINT frac; int last_sample; /* integer down sample */ int iratio; /* integer divison ratio */ int icount, isum; int inv; } ReSampleChannelContext; typedef struct ReSampleContext { ReSampleChannelContext channel_ctx[2]; float ratio; /* channel convert */ int input_channels, output_channels, filter_channels; } ReSampleContext; ReSampleContext *m_context; //////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// void init_mono_resample(ReSampleChannelContext *s, float ratio) { ratio = (float)(1.0 / ratio); s->iratio = (int)floorf(ratio); if (s->iratio == 0) s->iratio = 1; s->incr = (int)((ratio / s->iratio) * FRAC); s->frac = FRAC; s->last_sample = 0; s->icount = s->iratio; s->isum = 0; s->inv = (FRAC / s->iratio); } /* fractional audio resampling */ int fractional_resample(ReSampleChannelContext *s, short *output, short *input, int nb_samples) { unsigned int frac, incr; int l0, l1; short *q, *p, *pend; l0 = s->last_sample; incr = s->incr; frac = s->frac; p = input; pend = input + nb_samples; q = output; l1 = *p++; for(;;) { /* interpolate */ *q++ = (l0 * (FRAC - frac) + l1 * frac) >> FRAC_BITS; frac = frac + s->incr; while (frac >= FRAC) { frac -= FRAC; if (p >= pend) goto the_end; l0 = l1; l1 = *p++; } } the_end: s->last_sample = l1; s->frac = frac; return q - output; } int integer_downsample(ReSampleChannelContext *s, short *output, short *input, int nb_samples) { short *q, *p, *pend; int c, sum; p = input; pend = input + nb_samples; q = output; c = s->icount; sum = s->isum; for(;;) { sum += *p++; if (--c == 0) { *q++ = (sum * s->inv) >> FRAC_BITS; c = s->iratio; sum = 0; } if (p >= pend) break; } s->isum = sum; s->icount = c; return q - output; } /* n1: number of samples */ void stereo_to_mono(short *output, short *input, int n1) { short *p, *q; int n = n1; p = input; q = output; while (n >= 4) { q[0] = (p[0] + p[1]) >> 1; q[1] = (p[2] + p[3]) >> 1; q[2] = (p[4] + p[5]) >> 1; q[3] = (p[6] + p[7]) >> 1; q += 4; p += 8; n -= 4; } while (n > 0) { q[0] = (p[0] + p[1]) >> 1; q++; p += 2; n--; } } /* n1: number of samples */ void mono_to_stereo(short *output, short *input, int n1) { short *p, *q; int n = n1; int v; p = input; q = output; while (n >= 4) { v = p[0]; q[0] = v; q[1] = v; v = p[1]; q[2] = v; q[3] = v; v = p[2]; q[4] = v; q[5] = v; v = p[3]; q[6] = v; q[7] = v; q += 8; p += 4; n -= 4; } while (n > 0) { v = p[0]; q[0] = v; q[1] = v; q += 2; p += 1; n--; } } /* XXX: should use more abstract 'N' channels system */ void stereo_split(short *output1, short *output2, short *input, int n) { int i; for(i=0;i<n;i++) { *output1++ = *input++; *output2++ = *input++; } } void stereo_mux(short *output, short *input1, short *input2, int n) { int i; for(i=0;i<n;i++) { *output++ = *input1++; *output++ = *input2++; } } void ac3_5p1_mux(short *output, short *input1, short *input2, int n) { int i; short l,r; for(i=0;i<n;i++) { l=*input1++; r=*input2++; *output++ = l; /* left */ *output++ = (l/2)+(r/2); /* center */ *output++ = r; /* right */ *output++ = 0; /* left surround */ *output++ = 0; /* right surroud */ *output++ = 0; /* low freq */ } } int mono_resample(ReSampleChannelContext *s, short *output, short *input, int nb_samples) { short *buf1; short *buftmp; buf1= (short*)av_malloc( nb_samples * sizeof(short) ); /* first downsample by an integer factor with averaging filter */ if (s->iratio > 1) { buftmp = buf1; nb_samples = integer_downsample(s, buftmp, input, nb_samples); } else { buftmp = input; } /* then do a fractional resampling with linear interpolation */ if (s->incr != FRAC) { nb_samples = fractional_resample(s, output, buftmp, nb_samples); } else { memcpy(output, buftmp, nb_samples * sizeof(short)); } av_free(buf1); return nb_samples; } //========================================================================================================== int init_PCM_resample(int output_channels, int input_channels, int output_rate, int input_rate) { int i; if ( input_channels > 2) { printf("Resampling with input channels greater than 2 unsupported."); return -1; } m_context = (ReSampleContext *)malloc(sizeof(ReSampleContext)); memset(m_context, 0, sizeof(ReSampleContext)); m_context->ratio = (float)output_rate / (float)input_rate; m_context->input_channels = input_channels; m_context->output_channels = output_channels; m_context->filter_channels = m_context->input_channels; if (m_context->output_channels < m_context->filter_channels) m_context->filter_channels = m_context->output_channels; /* * ac3 output is the only case where filter_channels could be greater than 2. * input channels can't be greater than 2, so resample the 2 channels and then * expand to 6 channels after the resampling. */ if(m_context->filter_channels>2) m_context->filter_channels = 2; for(i=0;i<m_context->filter_channels;i++) { init_mono_resample(&m_context->channel_ctx[i], m_context->ratio); } return 0; } /* resample audio. 'nb_samples' is the number of input samples */ /* XXX: optimize it ! */ /* XXX: do it with polyphase filters, since the quality here is HORRIBLE. Return the number of samples available in output */ // 重采样 // output para1:重采样后输出的数据 // input para2:输入数据 // para3:此帧音频的采样点数 // 注:44100的采样点数固定为1024，其他采样率不固定，需要通道此帧长度，通道数，位宽，计算采样点数 int start_PCM_resample(short *output, short *input, int in_len) { int i, nb_samples1; short *bufin[2]; short *bufout[2]; short *buftmp2[2], *buftmp3[2]; int lenout; int nb_samples = in_len/(m_context->input_channels * sizeof(short)); if (m_context->input_channels == m_context->output_channels && m_context->ratio == 1.0) { /* nothing to do */ memcpy(output, input, nb_samples * m_context->input_channels * sizeof(short)); return nb_samples; } /* XXX: move those malloc to resample init code */ bufin[0]= (short*) av_malloc( nb_samples * sizeof(short) ); bufin[1]= (short*) av_malloc( nb_samples * sizeof(short) ); /* make some zoom to avoid round pb */ lenout= (int)(nb_samples * m_context->ratio) + 16; bufout[0]= (short*) av_malloc( lenout * sizeof(short) ); bufout[1]= (short*) av_malloc( lenout * sizeof(short) ); if (m_context->input_channels == 2 && m_context->output_channels == 1) { buftmp2[0] = bufin[0]; buftmp3[0] = output; stereo_to_mono(buftmp2[0], input, nb_samples); } else if (m_context->output_channels >= 2 && m_context->input_channels == 1) { buftmp2[0] = input; buftmp3[0] = bufout[0]; } else if (m_context->output_channels >= 2) { buftmp2[0] = bufin[0]; buftmp2[1] = bufin[1]; buftmp3[0] = bufout[0]; buftmp3[1] = bufout[1]; stereo_split(buftmp2[0], buftmp2[1], input, nb_samples); } else { buftmp2[0] = input; buftmp3[0] = output; } /* resample each channel */ nb_samples1 = 0; /* avoid warning */ for(i=0;i<m_context->filter_channels;i++) { nb_samples1 = mono_resample(&m_context->channel_ctx[i], buftmp3[i], buftmp2[i], nb_samples); } if (m_context->output_channels == 2 && m_context->input_channels == 1) { mono_to_stereo(output, buftmp3[0], nb_samples1); } else if (m_context->output_channels == 2) { stereo_mux(output, buftmp3[0], buftmp3[1], nb_samples1); } else if (m_context->output_channels == 6) { ac3_5p1_mux(output, buftmp3[0], buftmp3[1], nb_samples1); } av_free(bufin[0]); av_free(bufin[1]); av_free(bufout[0]); av_free(bufout[1]); return nb_samples1*m_context->output_channels*sizeof(short); } // 去初始化 int uninit_PCM_resample() { if(NULL == m_context) { free(m_context); m_context = NULL; } return 0; } // 16bit_to_8bit(注意输出数据是有符号的还是无符号的) // output: para 1: 8bit的数据 // input: para 2: 16bit数据 // para 3: 要转换数据的次数，为原数据长度的一半，因为一次转换2个字节 int mono_16bit_to_8bit(unsigned char* lp8bits, short* lp16bits, int len) { int i=0; for(i=0; i<len; i++) { *lp8bits++ = ((*lp16bits++) >> 8) + 128; } return i>>1; } // 8bit_to_16bit(注意:输出数据是有符号的还是无符号的) // output: para 1: 16bit的数据 // input: para 2: 8bit数据 // para 3: 要转换数据的次数，为原数据长度， //注:因为一次转换1个字节变两个字节，所以转换后数据的总长度为8位数据的两倍 int mono_8bit_to_16bit(short* lp16bits, unsigned char* lp8bits, int len) { int i=0; for(i=0; i<len; i++) { *lp16bits++ = ((*lp8bits++) -128) << 8; } return i<<1; } // 位宽转换 // input : para1 重采样对象 // para2 flag : [8]--16位转8位 ,[16]--8位转16位 // para3 输入数据长度 // para4 输入数据 // output: para5 输出数据 // return 输出数据长度 int bit_wide_transform(int flag,int in_len,unsigned char* in_buf,unsigned char* out_buf) { // 转换次数，转换单位是源数据一次采样， // 即8位转16位:源数据是一次转换一个字节 // 即16位转8位:源数据是一次转换两个字节 int ns_sample = 0; if(8 == flag) { ns_sample = in_len/2; mono_16bit_to_8bit(out_buf, (short *)in_buf, ns_sample); return ns_sample*1; } else if(16 == flag) { ns_sample = in_len; mono_8bit_to_16bit((short*)out_buf, in_buf, ns_sample); return ns_sample*2; } } // 音量控制 // output: para1 输出数据 // input : para2 输入数据 // para3 输入长度 // para4 音量控制参数,有效控制范围[0,100] int volume_control(short* out_buf,short* in_buf,int in_len, float in_vol) { int i,tmp; // in_vol[0,100] float vol = in_vol - 98; if(-98 < vol && vol <0 ) { vol = 1/(vol*(-1)); } else if(0 <= vol && vol <= 1) { vol = 1; } /*else if(1 < vol && vol <= 2) { vol = vol; }*/ else if(vol <= -98) { vol = 0; } else if(2 <= vol) { vol = 2; } for(i=0; i<in_len/2; i++) { tmp = in_buf[i]*vol; if(tmp > 32767) { tmp = 32767; } else if( tmp < -32768) { tmp = -32768; } out_buf[i] = tmp; } return 0; } //=========================================================================
========================================================================= //test.c #include <stdio.h> #include <stdlib.h> #include <errno.h> #include "rresample.h" int openFileWrite(FILE** fp,char *name) { *fp = fopen(name,"w+"); if(NULL == *fp) { return -1; } else { return 0; } } int openFileRead(FILE** fp,char *name) { *fp = fopen(name,"r+"); if(NULL == *fp) { return -1; } else { return 0; } } int overreadFile(FILE *fp, unsigned char *buf,int *len_t) { if(NULL == fp || NULL == buf) { return -1; } int len = 0; int len1 = 0; len1 = ftell(fp); fseek(fp, 0, SEEK_END); len = ftell(fp); fseek(fp, 0, SEEK_SET); printf("len[%d]--len1[%d]\n",len,len1); *len_t = len; int i=0; while(1) { if(len < 1024) { //printf("66666666666666\n"); if(1!= fread(buf+1024*i, len, 1, fp)) { perror("read error---111[]\n"); printf("read error---111[i:%d]\n",i); return -1; } } else { //printf("999999999999999\n"); if(1 != fread(buf+1024*i, 1024, 1, fp)) { perror("read error---222[\n"); printf("read error---222[i:%d]\n",i); return -1; } } //printf("22223323333333333\n"); i++; //printf("111111111111\n"); len -= 1024; //printf("2222222222222\n"); if(len <= 0) { break; } } printf("read file successful\n"); printf("1111111111\n"); printf("2222222222222---*len_t[%d]\n",*len_t); return 0; } int writeAllFile(FILE *fp, unsigned char *buf, int len) { if(NULL == fp || NULL == buf || 0 == len) { printf("NULL == fp || NULL == buf || 0 == len write \n"); return -1; } printf("write error---len[%d]\n",len); int i=0; while(1) { if(len < 1024) { if(1!= fwrite(buf+1024*i, len, 1, fp)) { perror("\n"); printf("write error-len[%d]--111[i:%d]\n",len,i); return -1; } } else { if(1 != fwrite(buf+1024*i, 1024, 1, fp)) { perror("write error---222[\n"); printf("write error---222[i:%d]\n",i); return -1; } } i++; len -= 1024; if(len <= 0) { break; } } printf("write file successful\n"); return 0; } #define MAX_BUF_SIZE 1024*1024*120 int main(int argc, char *argv[]) { #if 1 FILE *fp1 = NULL; FILE *fp2 = NULL; FILE *fp3 = NULL; int len = 0; unsigned char *read_buf = (unsigned char *)malloc(MAX_BUF_SIZE); unsigned char *write_buf = (unsigned char *)malloc(MAX_BUF_SIZE); if(NULL == read_buf || NULL == write_buf) { printf("malloc fail\n"); return -1; } if(0 != openFileRead(&fp1,argv[1])) { printf("open [%s] fail\n",argv[1]); return -1; } if(0 != openFileWrite(&fp2,argv[2])) { printf("open [%s] fail\n",argv[2]); return -1; } if(0 != overreadFile(fp1, (unsigned char *)read_buf, &len)) { printf("overreadFile fail\n"); return -1; } int ns_sample = 1024; int ns_sample1 = 0; int i = 0; int len_t = len; int in_len = 0; int out_len = 0; int n =0; unsigned char *p1 = write_buf; unsigned char *p2 = read_buf; int ret =-1; #if 1 init_PCM_resample(2, 1, 44100, 11025); while(1) { if(len_t > 4096) { in_len = 4096; } else { in_len = len_t; } //volume_control((short*)p1,(short*)p2,in_len, 80); //n = bit_wide_transform(16,in_len, p2, p1); n = start_PCM_resample((short *)p1, (short *)p2,in_len); out_len += n; p2 += in_len; p1 += n; len_t -= 4096; if(len_t <= 0) { printf("I break---3233333333---\n"); break; } } #endif uninit_PCM_resample(); if(0 != writeAllFile(fp2, (unsigned char *)write_buf, out_len)) { printf("writeAllFile fail\n"); return -1; } printf("complete resample================\n"); free(write_buf); write_buf = NULL; free(read_buf); read_buf = NULL; #endif return 0; } |
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