示例#1
0
void CODEC2_WIN32SUPPORT codec2_decode(struct CODEC2 *c2, short speech[], const unsigned char *bits)
{
    codec2_decode_ber(c2, speech, bits, 0.0);
}
示例#2
0
文件: c2dec.c 项目: avesus/codec2
int main(int argc, char *argv[])
{
    int            mode;
    void          *codec2;
    FILE          *fin;
    FILE          *fout;
    FILE          *fber = NULL;
    short         *buf;
    unsigned char *bits;
    float         *softdec_bits;
    int            nsam, nbit, nbyte, i, byte, frames, bits_proc, bit_errors, error_mode;
    int            nstart_bit, nend_bit, bit_rate;
    int            state, next_state;
    float          ber, r, burst_length, burst_period, burst_timer, ber_est;
    unsigned char  mask;
    int            natural, dump, softdec, bit, ret;

    char* opt_string = "h:";
    struct option long_options[] = {
        { "ber", required_argument, NULL, 0 },
        { "startbit", required_argument, NULL, 0 },
        { "endbit", required_argument, NULL, 0 },
        { "berfile", required_argument, NULL, 0 },
        { "natural", no_argument, &natural, 1 },
        { "softdec", no_argument, &softdec, 1 },
        #ifdef DUMP
        { "dump", required_argument, &dump, 1 },
        #endif
        { "help", no_argument, NULL, 'h' },
        { NULL, no_argument, NULL, 0 }
    };
    int num_opts=sizeof(long_options)/sizeof(struct option);
 
    if (argc < 4)
        print_help(long_options, num_opts, argv);
    
    if (strcmp(argv[1],"3200") == 0)
	mode = CODEC2_MODE_3200;
    else if (strcmp(argv[1],"2400") == 0)
	mode = CODEC2_MODE_2400;
    else if (strcmp(argv[1],"1600") == 0)
	mode = CODEC2_MODE_1600;
    else if (strcmp(argv[1],"1400") == 0)
	mode = CODEC2_MODE_1400;
    else if (strcmp(argv[1],"1300") == 0)
	mode = CODEC2_MODE_1300;
    else if (strcmp(argv[1],"1200") == 0)
	mode = CODEC2_MODE_1200;
    else if (strcmp(argv[1],"700") == 0)
	mode = CODEC2_MODE_700;
    else {
	fprintf(stderr, "Error in mode: %s.  Must be 3200, 2400, 1600, 1400, 1300, 1200, or 700\n", argv[1]);
	exit(1);
    }
    bit_rate = atoi(argv[1]);

    if (strcmp(argv[2], "-")  == 0) fin = stdin;
    else if ( (fin = fopen(argv[2],"rb")) == NULL ) {
	fprintf(stderr, "Error opening input bit file: %s: %s.\n",
         argv[2], strerror(errno));
	exit(1);
    }

    if (strcmp(argv[3], "-") == 0) fout = stdout;
    else if ( (fout = fopen(argv[3],"wb")) == NULL ) {
	fprintf(stderr, "Error opening output speech file: %s: %s.\n",
         argv[3], strerror(errno));
	exit(1);
    }

    error_mode = NONE;
    ber = 0.0;
    burst_length = burst_period = 0.0;
    burst_timer = 0.0;
    dump = natural = softdec = 0;

    codec2 = codec2_create(mode);
    nsam = codec2_samples_per_frame(codec2);
    nbit = codec2_bits_per_frame(codec2);
    buf = (short*)malloc(nsam*sizeof(short));
    nbyte = (nbit + 7) / 8;
    bits = (unsigned char*)malloc(nbyte*sizeof(char));
    softdec_bits = (float*)malloc(nbit*sizeof(float));
    frames = bit_errors = bits_proc = 0;
    nstart_bit = 0;
    nend_bit = nbit-1;

    while(1) {
        int option_index = 0;
        int opt = getopt_long(argc, argv, opt_string, 
                    long_options, &option_index);
        if (opt == -1)
            break;

        switch (opt) {
        case 0:
            if(strcmp(long_options[option_index].name, "ber") == 0) {
                ber = atof(optarg);
                error_mode = UNIFORM;
            } else if(strcmp(long_options[option_index].name, "startbit") == 0) {
	        nstart_bit = atoi(optarg);
            } else if(strcmp(long_options[option_index].name, "endbit") == 0) {
	        nend_bit = atoi(optarg);
             } else if(strcmp(long_options[option_index].name, "berfile") == 0) {
	        if ((fber = fopen(optarg,"wt")) == NULL) {
	            fprintf(stderr, "Error opening BER file: %s %s.\n",
                            optarg, strerror(errno));
                    exit(1);
                }
            
            } 
            #ifdef DUMP
            else if(strcmp(long_options[option_index].name, "dump") == 0) {
                if (dump) 
	            dump_on(optarg);
            }
            #endif
            break;

        case 'h':
            print_help(long_options, num_opts, argv);
            break;

        default:
            /* This will never be reached */
            break;
        }
    }
    assert(nend_bit <= nbit);
    codec2_set_natural_or_gray(codec2, !natural);
    //printf("%d %d\n", nstart_bit, nend_bit);
 
    //fprintf(stderr, "softdec: %d natural: %d\n", softdec, natural);
    if (softdec)
        ret = (fread(softdec_bits, sizeof(float), nbit, fin) == (size_t)nbit);
    else
        ret = (fread(bits, sizeof(char), nbyte, fin) == (size_t)nbyte);
      
    while(ret) {
	frames++;

        // apply bit errors, MSB of byte 0 is bit 0 in frame, only works in packed mode
        
	if ((error_mode == UNIFORM) || (error_mode == UNIFORM_RANGE)) {
            assert(softdec == 0);
	    for(i=nstart_bit; i<nend_bit+1; i++) {
		r = (float)rand()/RAND_MAX;
		if (r < ber) {
		    byte = i/8;
		    //printf("nbyte %d nbit %d i %d byte %d bits[%d] 0x%0x ", nbyte, nbit, i, byte, byte, bits[byte]);
		    mask = 1 << (7 - i + byte*8);
                    bits[byte] ^= mask;
		    //printf("shift: %d mask: 0x%0x bits[%d] 0x%0x\n", 7 - i + byte*8, mask, byte, bits[byte] );
		    bit_errors++;
 		}
                bits_proc++;
	    }
	}

	if (error_mode == TWO_STATE) {
            assert(softdec == 0);
            burst_timer += (float)nbit/bit_rate;
            fprintf(stderr, "burst_timer: %f  state: %d\n", burst_timer, state);

            next_state = state;
            switch(state) {
            case 0:

                /* clear channel state - no bit errors */

                if (burst_timer > (burst_period - burst_length))
                    next_state = 1;
                break;

            case 1:
                
                /* burst error state - 50% bit error rate */

                for(i=nstart_bit; i<nend_bit+1; i++) {
                    r = (float)rand()/RAND_MAX;
                    if (r < 0.5) {
                        byte = i/8;
                        bits[byte] ^= 1 << (7 - i + byte*8);
                        bit_errors++;
                    }
                    bits_proc++;
		}

                if (burst_timer > burst_period) {
                    burst_timer = 0.0;
                    next_state = 0;
                }
                break;

	    }
               
            state = next_state;
        }

        if (fber != NULL) {
            if (fread(&ber_est, sizeof(float), 1, fber) != 1) {
                fprintf(stderr, "ran out of BER estimates!\n");
                exit(1);
            }
            //fprintf(stderr, "ber_est: %f\n", ber_est);
        }
        else
            ber_est = 0.0;
            
        if (softdec) {
            /* pack bits, MSB received first  */

            bit = 7; byte = 0;
            memset(bits, 0, nbyte);
            for(i=0; i<nbit; i++) {
                bits[byte] |= ((softdec_bits[i] < 0.0) << bit);
                bit--;
                if (bit < 0) {
                    bit = 7;
                    byte++;
                }
            }
            codec2_set_softdec(codec2, softdec_bits);
        }

	codec2_decode_ber(codec2, buf, bits, ber_est);
 	fwrite(buf, sizeof(short), nsam, fout);

	//if this is in a pipeline, we probably don't want the usual
        //buffering to occur

        if (fout == stdout) fflush(stdout);
        if (fin == stdin) fflush(stdin);         

        if (softdec)
            ret = (fread(softdec_bits, sizeof(float), nbit, fin) == (size_t)nbit);
        else
            ret = (fread(bits, sizeof(char), nbyte, fin) == (size_t)nbyte);
    }

    if (error_mode)
	fprintf(stderr, "actual BER: %1.3f\n", (float)bit_errors/bits_proc);

    codec2_destroy(codec2);

    free(buf);
    free(bits);
    free(softdec_bits);
    fclose(fin);
    fclose(fout);

    return 0;
}