musicin.c

MPEG 2的音频编码软件。喜欢多媒体的开发人员可以看看。

    if(info->copyright) printf(">>> Copyrighted material\n");
    else                printf(">>> Material not copyrighted\n");
 
    printf("Is this the original? (y/<n>): ");
    gets(t);
    if (*t == 'y' || *t == 'Y') info->original = 1;
    else                        info->original = 0;
    if(info->original) printf(">>> Original material\n");
    else               printf(">>> Material not original\n");
 
    printf("Do you wish to exit (last chance before encoding)? (y/<n>): ");
    gets(t);
    if (*t == 'y' || *t == 'Y') exit(0);
}

/************************************************************************
*
* parse_args
*
* PURPOSE:  Sets encoding parameters to the specifications of the
* command line.  Default settings are used for parameters
* not specified in the command line.
*
* SEMANTICS:  The command line is parsed according to the following
* syntax:
*
* -l  is followed by the layer number
* -m  is followed by the mode
* -p  is followed by the psychoacoustic model number
* -s  is followed by the sampling rate
* -b  is followed by the total bitrate, irrespective of the mode
* -d  is followed by the emphasis flag
* -c  is followed by the copyright/no_copyright flag
* -o  is followed by the original/not_original flag
* -e  is followed by the error_protection on/off flag
*
* If the input file is in AIFF format, the sampling frequency is read
* from the AIFF header.
*
* The input and output filenames are read into #inpath# and #outpath#.
*
************************************************************************/
 
void
parse_args(argc, argv, fr_ps, psy, num_samples, inPath, outPath)
int     argc;
char    **argv;
frame_params  *fr_ps;
int     *psy;
unsigned long *num_samples;
char    inPath[MAX_NAME_SIZE];
char    outPath[MAX_NAME_SIZE];
{
   FLOAT srate;
   int   brate;
   layer *info = fr_ps->header;
   int   err = 0, i = 0;
   IFF_AIFF pcm_aiff_data;
   long samplerate;
   long soundPosition;
 
   /* preset defaults */
   inPath[0] = '\0';   outPath[0] = '\0';
   info->lay = DFLT_LAY;
   switch(DFLT_MOD) {
      case 's': info->mode = MPG_MD_STEREO; info->mode_ext = 0; break;
      case 'd': info->mode = MPG_MD_DUAL_CHANNEL; info->mode_ext=0; break;
      case 'j': info->mode = MPG_MD_JOINT_STEREO; break;
      case 'm': info->mode = MPG_MD_MONO; info->mode_ext = 0; break;
      default:
         fprintf(stderr, "%s: Bad mode dflt %c\n", programName, DFLT_MOD);
         abort();
   }
   *psy = DFLT_PSY;
   if((info->sampling_frequency = SmpFrqIndex((long)(1000*DFLT_SFQ), &info->version)) < 0) {
      fprintf(stderr, "%s: bad sfrq default %.2f\n", programName, DFLT_SFQ);
      abort();
   }
  info->bitrate_index = 14;
  brate = 0;
   switch(DFLT_EMP) {
      case 'n': info->emphasis = 0; break;
      case '5': info->emphasis = 1; break;
      case 'c': info->emphasis = 3; break;
      default: 
         fprintf(stderr, "%s: Bad emph dflt %c\n", programName, DFLT_EMP);
         abort();
   }
   info->copyright = 0; info->original = 0; info->error_protection = FALSE;
 
   /* process args */
   while(++i<argc && err == 0) {
      char c, *token, *arg, *nextArg;
      int  argUsed;
 
      token = argv[i];
      if(*token++ == '-') {
         if(i+1 < argc) nextArg = argv[i+1];
         else           nextArg = "";
         argUsed = 0;
         while( (c = *token++) ) {
            if(*token /* NumericQ(token) */) arg = token;
            else                             arg = nextArg;
            switch(c) {
               case 'l':        info->lay = atoi(arg); argUsed = 1;
                  if(info->lay<1 || info->lay>3) {
                     fprintf(stderr,"%s: -l layer must be 1, 2, or 3, not %s\n",
                          programName, arg);
                     err = 1;
                  }
                  break;
               case 'm':        argUsed = 1;
                  if (*arg == 's')
                    { info->mode = MPG_MD_STEREO; info->mode_ext = 0; }
                  else if (*arg == 'd')
                    { info->mode = MPG_MD_DUAL_CHANNEL; info->mode_ext=0; }
                  else if (*arg == 'j')
                    { info->mode = MPG_MD_JOINT_STEREO; }
                  else if (*arg == 'm')
                    { info->mode = MPG_MD_MONO; info->mode_ext = 0; }
                  else {
                    fprintf(stderr,"%s: -m mode must be s/d/j/m not %s\n",
                            programName, arg);
                    err = 1;
                  }
                  break;
               case 'p':        *psy = atoi(arg); argUsed = 1;
                  if(*psy<1 || *psy>2) {
                     fprintf(stderr,"%s: -p model must be 1 or 2, not %s\n",
                             programName, arg);
                     err = 1;
                  }
                  break;

               case 's':
                  argUsed = 1;
                  srate = atof( arg );
                  /* samplerate = rint( 1000.0 * srate ); $A  */
                  samplerate = (long) (( 1000.0 * srate ) + 0.5);
                  if( (info->sampling_frequency =
          SmpFrqIndex((long) samplerate, &info->version)) < 0 )
                      err = 1;
                  break;
                  
               case 'b':        
        argUsed = 1;
      brate = atoi(arg); 
      break;
               case 'd':        argUsed = 1;
                  if (*arg == 'n')                    info->emphasis = 0;
                  else if (*arg == '5')               info->emphasis = 1;
                  else if (*arg == 'c')               info->emphasis = 3;
                  else {
                     fprintf(stderr,"%s: -d emp must be n/5/c not %s\n",
                             programName, arg);
                     err = 1;
                  }
                  break;
                case 'c':       info->copyright = 1; break;
                case 'o':       info->original  = 1; break;
                case 'e':       info->error_protection = TRUE; break;
                default:        fprintf(stderr,"%s: unrec option %c\n",
                                        programName, c);
                                err = 1; break;
            }
            if(argUsed) {
               if(arg == token)    token = "";   /* no more from token */
               else                ++i;          /* skip arg we used */
               arg = ""; argUsed = 0;
            }
         }
      }
      else {
         if(inPath[0] == '\0')       strcpy(inPath, argv[i]);
         else if(outPath[0] == '\0') strcpy(outPath, argv[i]);
         else {
            fprintf(stderr,"%s: excess arg %s\n", programName, argv[i]);
            err = 1;
         }
      }
   }

   if(err || inPath[0] == '\0') usage();  /* never returns */
 
   if(outPath[0] == '\0') {
#ifdef MS_DOS
      /* replace old extension with new one, 1992-08-19, 1995-06-12 shn */
      new_ext(inPath, DFLT_EXT, outPath);
#else
      strcpy(outPath, inPath);
      strcat(outPath, DFLT_EXT);
#endif
   }

   if ((musicin = fopen(inPath, "rb")) == NULL) {
      printf("Could not find \"%s\".\n", inPath);
      exit(1);
   }
 
   open_bit_stream_w(&bs, outPath, BUFFER_SIZE);

   if ((soundPosition = aiff_read_headers(musicin, &pcm_aiff_data)) != -1) {

      printf(">>> Using Audio IFF sound file headers\n");

      aiff_check(inPath, &pcm_aiff_data, &info->version);

      if (fseek(musicin, soundPosition, SEEK_SET) != 0) {
         printf("Could not seek to PCM sound data in \"%s\".\n", inPath);
         exit(1);
      }

      info->sampling_frequency = SmpFrqIndex((long)pcm_aiff_data.sampleRate, &info->version);
      printf(">>> %f Hz sampling frequency selected\n",
             pcm_aiff_data.sampleRate);

      /* Determine number of samples in sound file */
#ifndef MS_DOS
      *num_samples = pcm_aiff_data.numChannels *
                     pcm_aiff_data.numSampleFrames;
#else
      *num_samples = (long)(pcm_aiff_data.numChannels) *
                     (long)(pcm_aiff_data.numSampleFrames);
#endif
      if ( pcm_aiff_data.numChannels == 1 ) {
        info->mode = MPG_MD_MONO;
        info->mode_ext = 0;
      }
   }
   else {    /* Not using Audio IFF sound file headers. */

      if (fseek(musicin, 0, SEEK_SET) != 0) {
         printf("Could not seek to PCM sound data in \"%s\".\n", inPath);
         exit(1);
      }
 
      /* Declare sound file to have "infinite" number of samples. */
      *num_samples = MAX_U_32_NUM;

   }
   if ( brate == 0 )
    brate = bitrate[info->version][info->lay-1][14];
   if( (info->bitrate_index = BitrateIndex(info->lay, brate, info->version)) < 0) err=1;
   if(err || inPath[0] == '\0') usage();  /* never returns */

}

/************************************************************************
*
* print_config
*
* PURPOSE:  Prints the encoding parameters used
*
************************************************************************/
 
void print_config( frame_params *fr_ps, int *psy, char *inPath, char *outPath)
{
 layer *info = fr_ps->header;
 
   printf("Encoding configuration:\n");
   printf("Algorithm=%s\n", version_names[info->version]);
   if(info->mode != MPG_MD_JOINT_STEREO)
      printf("Layer=%s   mode=%s   extn=%d   psy model=%d\n",
             layer_names[info->lay-1], mode_names[info->mode],
             info->mode_ext, *psy);
   else printf("Layer=%s   mode=%s   extn=data dependant   psy model=%d\n",
               layer_names[info->lay-1], mode_names[info->mode], *psy);
   printf("samp frq=%.1f kHz   total bitrate=%d kbps\n",
          s_freq[info->version][info->sampling_frequency],
          bitrate[info->version][info->lay-1][info->bitrate_index]);
   printf("de-emph=%d   c/right=%d   orig=%d   errprot=%s\n",
          info->emphasis, info->copyright, info->original,
          ((info->error_protection) ? "on" : "off"));
   printf("input file: '%s'   output file: '%s'\n", inPath, outPath);
}




 
/************************************************************************
*
* main
*
* PURPOSE:  MPEG I Encoder supporting layers 1 and 2, and 3, with
* psychoacoustic models 1 (MUSICAM) and 2 (AT&T)
*
* SEMANTICS:  One overlapping frame of audio of up to 2 channels are
* processed at a time in the following order:
* (associated routines are in parentheses)
*
* 1.  Filter sliding window of data to get 32 subband
* samples per channel.
* (window_subband,filter_subband)
*
* 2.  If joint stereo mode, combine left and right channels
* for subbands above #jsbound#.
* (*_combine_LR)
*
* 3.  Calculate scalefactors for the frame, and if layer 2,
* also calculate scalefactor select information.
* (*_scale_factor_calc)
*
* 4.  Calculate psychoacoustic masking levels using selected
* psychoacoustic model.
* (*_Psycho_One, psycho_anal)
*
* 5.  Perform iterative bit allocation for subbands with low
* mask_to_noise ratios using masking levels from step 4.
* (*_main_bit_allocation)
*
* 6.  If error protection flag is active, add redundancy for
* error protection.
* (*_CRC_calc)
*
* 7.  Pack bit allocation, scalefactors, and scalefactor select
* information (layer 2) onto bitstream.
* (*_encode_bit_alloc,*_encode_scale,II_transmission_pattern)
*
* 8.  Quantize subbands and pack them into bitstream
* (*_subband_quantization, *_sample_encoding)
*
************************************************************************/

int frameNum=0;

void main(argc, argv)
int     argc;
char    **argv;
{
    typedef double SBS[2][3][SCALE_BLOCK][SBLIMIT];
    SBS  FAR        *sb_sample;
    L3SBS  FAR        *l3_sb_sample;
    typedef double JSBS[3][SCALE_BLOCK][SBLIMIT];
    JSBS FAR        *j_sample;
    typedef double IN[2][HAN_SIZE];
    IN   FAR        *win_que;
    typedef unsigned int SUB[2][3][SCALE_BLOCK][SBLIMIT];
    SUB  FAR        *subband;
    
    frame_params fr_ps;
    layer info;
    char original_file_name[MAX_NAME_SIZE];
    char encoded_file_name[MAX_NAME_SIZE];
    short FAR **win_buf;
    static short FAR buffer[2][1152];
    static unsigned int bit_alloc[2][SBLIMIT], scfsi[2][SBLIMIT];
    static unsigned int scalar[2][3][SBLIMIT], j_scale[3][SBLIMIT];
    static double FAR ltmin[2][SBLIMIT], lgmin[2][SBLIMIT], max_sc[2][SBLIMIT];
    FLOAT snr32[32];
    short sam[2][1344]; /* was [1056]; */
    int whole_SpF, extra_slot = 0;
    double avg_slots_per_frame, frac_SpF, slot_lag;
    int model, stereo, error_protection;
    static unsigned int crc;
    int i, j, k, adb;
    unsigned long bitsPerSlot, samplesPerFrame;
    unsigned long frameBits, sentBits = 0;
    unsigned long num_samples;
    
#ifdef  MACINTOSH
    argc = ccommand( &argv );
#endif
    

    /* Most large variables are declared dynamically to ensure
       compatibility with smaller machines */
    
    sb_sample = (SBS FAR *) mem_alloc(sizeof(SBS), "sb_sample");
    l3_sb_sample = (L3SBS FAR *) mem_alloc(sizeof(SBS), "l3_sb_sample");
    j_sample = (JSBS FAR *) mem_alloc(sizeof(JSBS), "j_sample");
    win_que = (IN FAR *) mem_alloc(sizeof(IN), "Win_que");
    subband = (SUB FAR *) mem_alloc(sizeof(SUB),"subband");
    win_buf = (short FAR **) mem_alloc(sizeof(short *)*2, "win_buf");
 
    /* clear buffers */
    memset((char *) buffer, 0, sizeof(buffer));
    memset((char *) bit_alloc, 0, sizeof(bit_alloc));
    memset((char *) scalar, 0, sizeof(scalar));
    memset((char *) j_scale, 0, sizeof(j_scale));
    memset((char *) scfsi, 0, sizeof(scfsi));
    memset((char *) ltmin, 0, sizeof(ltmin));
    memset((char *) lgmin, 0, sizeof(lgmin));
    memset((char *) max_sc, 0, sizeof(max_sc));