Wav_Support_File.cpp

00001 /* Wav File Support */
00002 /* **************** */
00003 
00004 #include "mbed.h"
00005 //#include "misra_types.h"
00006 //#include "Wav_Support_File.h"
00007 
00008 #define DEBUG 0
00009 
00010 /* Function Prototypes */
00011 unsigned char wave_file_check(unsigned char *wave_array, FILE *open_file);
00012 
00013 
00014 /* Global Variables */
00015 struct wave_header_construction
00016                 {    char  identification_block[5];
00017                     unsigned int length_of_file;
00018                     char  identifier1[5];
00019                     char  identifier2[5];
00020                     unsigned int position_of_data;
00021                     unsigned short format_tag;
00022                     unsigned short number_of_channels;
00023                     unsigned int samples_per_second;                    
00024                     unsigned int bytes_per_second;
00025                     unsigned short bytes_per_sample;
00026                     unsigned short bits_per_sample;
00027                     char  marker[5];
00028                     unsigned int number_of_bits_in_sample;
00029                 } wave_file_info;
00030 
00031 
00032 
00033 
00034 
00035 /* Wave File Checker */
00036 unsigned char wave_file_check(unsigned char *wave_array, FILE *open_file)
00037     {
00038         unsigned char brk_flag = 0u;
00039         unsigned char x = 0u;
00040         unsigned char valid_sample = 0u;
00041         short ch = 0;
00042         
00043         if(DEBUG)  printf("\n\rPrinting out.WAV file header...\n\r");    
00044 
00045         for (x = 0; x < 0x2bu; x++)                                                /* Read the first 0x2b bytes of the file as this is the haeder informtation relating to sample rate etc. */
00046             {
00047                 ch = fgetc(open_file);                                            /* Get the first byte from the file */
00048                 if (ch == EOF)                                                  /* Check for eof */
00049                     {
00050                         if(DEBUG)  printf("   File too short to be a wave file\n\r");    /* If we have less than 0x2b then file is not a wave file. */
00051                         valid_sample = 0u;
00052                         brk_flag = 1u;
00053                     }
00054                 else{
00055                         wave_array[x] = ch;                                           /* Load data in to header file array */
00056                     }
00057                     
00058                 if (brk_flag == 1u) 
00059                     {
00060                         break;
00061                     }
00062             }
00063             
00064         if (brk_flag == 0u)                                                     /* OK we have downloaded the header into an Array. Lets check to see if its a valid file */
00065             {
00066                 if(DEBUG)  printf("   Identification block (4 ASCII bytes)= ");                                /* First 4 bytes are header block */
00067                 for (x = 0u; x < 4; x++) 
00068                     {
00069                         //putc(wave_array[x]);                                                       /* and write them on the screen */
00070                         wave_file_info.identification_block[x] = wave_array[x];
00071                     }
00072                 wave_file_info.identification_block[4] = 0;                                            /* add the string terminator on the end */
00073                 if(DEBUG)  printf(" '%s'\n\r", wave_file_info.identification_block);
00074     
00075                 
00076                 if(DEBUG)  printf("   Length of file (4 bytes) = ");                                        /* Length of file. */
00077                 for (x = 4u; x < 8u; x++) 
00078                     {
00079                         if(DEBUG)  printf("%d ",wave_array[x]);
00080                     }
00081                 wave_file_info.length_of_file =  ( ((unsigned int) wave_array[7] << 24) 
00082                                                  + ((unsigned int) wave_array[6] << 16) 
00083                                                  + ((unsigned int) wave_array[5] << 8) 
00084                                                  + ((unsigned int) wave_array[4]) ); 
00085                 if(DEBUG)  printf(" = %d bytes\n\r", wave_file_info.length_of_file);
00086 
00087             
00088                 if(DEBUG)  printf("   Identifier (4 ASCII bytes) = ");                                        /* indentifier string1 */
00089                 for (x = 8u; x < 12u; x++) 
00090                     {
00091                         //putc(wave_array[x]);                                                       /* and write them on the screen */
00092                         wave_file_info.identifier1[x-8] = wave_array[x];
00093                     }
00094                 wave_file_info.identification_block[4] = 0;                                            /* add the string terminator on the end */
00095                 if(DEBUG)  printf(" '%s'\n\r", wave_file_info.identifier1);
00096     
00097                 
00098                 if(DEBUG)  printf("   Identifier (4 ASCII bytes) = ");                                        /* Identifier String 2 */
00099                 for (x = 12; x < 16u; x++) 
00100                     {
00101                         //putc(wave_array[x]);                                                       /* and write them on the screen */
00102                         wave_file_info.identifier2[x-12] = wave_array[x];
00103                     }
00104                 wave_file_info.identifier2[4] = 0;                                                    /* add the string terminator on the end */
00105                 if(DEBUG)  printf(" '%s'\n\r", wave_file_info.identifier2);
00106                         
00107 
00108                 if(DEBUG)  printf("   Position of data (4 bytes) = ");                                        /* Position of data */
00109                 for (x = 16u; x < 20u; x++) 
00110                     {
00111                         if(DEBUG)  printf("%d ",wave_array[x]);
00112                     }
00113                 wave_file_info.position_of_data =  ( ((unsigned int) wave_array[19] << 24) 
00114                                                    + ((unsigned int) wave_array[18] << 16) 
00115                                                    + ((unsigned int) wave_array[17] << 8) 
00116                                                    + ((unsigned int) wave_array[16]) ); 
00117                 if(DEBUG)  printf(" = %d\n\r", wave_file_info.position_of_data);
00118 
00119             
00120                 if(DEBUG)  printf("   Format Tag - Always 1 for Wave PCM (2 bytes) = ");                    /* format tag */
00121                 for (x = 20u; x < 22u; x++) 
00122                     {
00123                         if(DEBUG)  printf("%d ",wave_array[x]);
00124                     }
00125                 wave_file_info.format_tag = ( ((unsigned int) wave_array[21] << 8) 
00126                                             + ((unsigned int) wave_array[20]) ); 
00127                 if(DEBUG)  printf(" = %d\n\r", wave_file_info.format_tag);
00128 
00129                         
00130                 if(DEBUG)  printf("   Number of channels (2 bytes) = ");                                    /* Number of channels, mono or steroeo */
00131                 for (x = 22u; x < 24u; x++) 
00132                     {
00133                         if(DEBUG)  printf("%d ",wave_array[x]);
00134                     }
00135                 wave_file_info.number_of_channels = ( ((unsigned int) wave_array[23] << 8) 
00136                                                     + ((unsigned int) wave_array[22]) ); 
00137                 if(DEBUG)  printf(" = %d channel(s)\n\r", wave_file_info.number_of_channels);
00138 
00139                     
00140                 if(DEBUG)  printf("   Samples per second (4 bytes) = ");                                     /* Samples per second */
00141                 for (x = 24u; x < 28u; x++) 
00142                     {
00143                         if(DEBUG)  printf("%d ",wave_array[x]);
00144                     }
00145                 wave_file_info.samples_per_second =( ((unsigned int) wave_array[27] << 24) 
00146                                                    + ((unsigned int) wave_array[26] << 16) 
00147                                                    + ((unsigned int) wave_array[25] << 8) 
00148                                                    + ((unsigned int) wave_array[24]) ); 
00149                 if(DEBUG)  printf(" = %d samples per sec\n\r", wave_file_info.samples_per_second);
00150 
00151                                 
00152                 if(DEBUG)  printf("   Bytes Per Second (4 bytes) = ");                                         /* Bytes per second */
00153                 for (x = 28u; x < 32u; x++) 
00154                     {
00155                         if(DEBUG)  printf("%d ",wave_array[x]);
00156                     }
00157                 wave_file_info.bytes_per_second =  ( ((unsigned int) wave_array[31] << 24) 
00158                                                    + ((unsigned int) wave_array[30] << 16) 
00159                                                    + ((unsigned int) wave_array[29] << 8) 
00160                                                    + ((unsigned int) wave_array[28]) ); 
00161                 if(DEBUG)  printf(" = %d bytes per sec\n\r", wave_file_info.bytes_per_second);
00162 
00163             
00164                 if(DEBUG)  printf("   Bytes Per Sample (2 bytes) = ");                                       /* Bytes per sample */
00165                 for (x = 32u; x < 34u; x++) 
00166                     {
00167                         if(DEBUG)  printf("%d ",wave_array[x]);
00168                     }
00169                 wave_file_info.bytes_per_sample =     ( ((unsigned int) wave_array[33] << 8) 
00170                                                     + ((unsigned int) wave_array[32]) ); 
00171                 if(DEBUG)  printf(" = %d bytes\n\r", wave_file_info.bytes_per_sample);
00172 
00173                     
00174                 if(DEBUG)  printf("   Bits Per Sample (2 bytes) = ");                                        /* Bits per sample */
00175                 for (x = 34u; x < 36u; x++) 
00176                     {
00177                         if(DEBUG)  printf("%d ",wave_array[x]);
00178                     }
00179                 wave_file_info.bits_per_sample = ( ((unsigned int) wave_array[35] << 8) 
00180                                                     + ((unsigned int) wave_array[34]) ); 
00181                 if(DEBUG)  printf(" = %d bits\n\r", wave_file_info.bits_per_sample);
00182 
00183                         
00184                 if(DEBUG)  printf("   Marker (4 ASCII bytes) = ");                                            /* Marker */
00185                 for (x = 36u; x < 40u; x++) 
00186                     {
00187                         //putc(wave_array[x]);
00188                         wave_file_info.marker[x-36] = wave_array[x];                        
00189                     }
00190                 wave_file_info.marker[4] = 0;
00191                 if(DEBUG)  printf(" '%s'\n\r", wave_file_info.marker);
00192                         
00193 
00194                 if(DEBUG)  printf("   The number of bits in the sample (4 bytes) = ");                         /* Number of bits per sample. */
00195                 for (x = 40u; x < 44u; x++) 
00196                     {
00197                         if(DEBUG)  printf("%d ",wave_array[x]);
00198                     }
00199                 wave_file_info.number_of_bits_in_sample =  (  ((unsigned int) wave_array[43] << 24) 
00200                                                                + ((unsigned int) wave_array[42] << 16) 
00201                                                                + ((unsigned int) wave_array[41] << 8) 
00202                                                                + ((unsigned int) wave_array[40]) ); 
00203                 if(DEBUG)  printf(" = %d bits\n\r", wave_file_info.number_of_bits_in_sample);
00204                     
00205             
00206                 /* Check for valid Wave file */
00207                 if (((wave_array[0] == 'R') && (wave_array[1] == 'I') && (wave_array[2] == 'F') && (wave_array[3] == 'F'))
00208                 &&  ((wave_array[8] == 'W') && (wave_array[9] == 'A') && (wave_array[0x0a] == 'V') && (wave_array[0x0b] == 'E'))
00209                 && ((wave_array[0x0c] == 'f') && (wave_array[0x0d] == 'm') && (wave_array[0x0e] == 't') && (wave_array[0x0f] == ' '))
00210                 && (wave_array[0x14] == 0x01)) valid_sample = 1u;
00211                 }
00212 
00213         if(DEBUG)  printf("Finished examining the .WAV file header\n\r");
00214         if (valid_sample == 1)
00215             {
00216                 if(DEBUG)  printf("Sample is a valid .WAV sample file\n\n\r");
00217             }
00218         else{
00219                 if(DEBUG)  printf("Sample is a NOT a valid .WAV sample file\n\n\r");    
00220             }    
00221 
00222         return valid_sample;
00223     }