1 /* libSoX lpc-10 format.
17  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
33   Write the bits in bits[0] through bits[len-1] to file f, in "packed"
36   bits is expected to be an array of len integer values, where each
39   several 8 bit characters. If len is not a multiple of 8, then the
40   last character is padded with 0 bits -- the padding is in the least
41   significant bits of the last byte. The 8 bit characters are "filled"
44 static void write_bits(sox_format_t * ft, INT32 *bits, int len)  in write_bits()  argument
49   uint8_t data; /* The contents of the next byte to place in the  in write_bits()
54    * bit of the byte, so initialize mask to 0x80.  The next byte of  in write_bits()
61   for (i = 0; i < len; i++) {  in write_bits()
67      * If the byte data is full, determined by mask becoming 0,  in write_bits()
68      * then write the byte to the output file, and reinitialize  in write_bits()
69      * data and mask for the next output byte.  Also add the byte  in write_bits()
70      * if (i == len-1), because if len is not a multiple of 8,  in write_bits()
73     if ((mask == 0) || (i == len-1)) {  in write_bits()
82   Read bits from file f into bits[0] through bits[len-1], in "packed"
85   Read ceiling(len/8) characters from file f, if that many are
89   fill bits[8] through bits[15], and so on. If ceiling(len/8)
90   characters are available to read, and len is not a multiple of 8,
96   the range 0 to len, inclusive. If it is less than len, it will
99 static int read_bits(sox_format_t * ft, INT32 *bits, int len)  in read_bits()  argument
105   for (i = 0; i < len; i++) {  in read_bits()
118   return (len);  in read_bits()
123   priv_t * lpc = (priv_t *)ft->priv;  in startread()
125   if ((lpc->decst = create_lpc10_decoder_state()) == NULL) {  in startread()
129   lpc->samples = LPC10_SAMPLES_PER_FRAME;  in startread()
135   priv_t * lpc = (priv_t *)ft->priv;  in startwrite()
137   if ((lpc->encst = create_lpc10_encoder_state()) == NULL) {  in startwrite()
141   lpc->samples = 0;  in startwrite()
146 static size_t read_samples(sox_format_t * ft, sox_sample_t *buf, size_t len)  in read_samples()  argument
148   priv_t * lpc = (priv_t *)ft->priv;  in read_samples()
151   while (nread < len) {  in read_samples()
154     if (lpc->samples == LPC10_SAMPLES_PER_FRAME) {  in read_samples()
160       lpc10_decode(bits, lpc->speech, lpc->decst);  in read_samples()
161       lpc->samples = 0;  in read_samples()
164     while (nread < len && lpc->samples < LPC10_SAMPLES_PER_FRAME)  in read_samples()
165       buf[nread++] = SOX_FLOAT_32BIT_TO_SAMPLE(lpc->speech[lpc->samples++], ft->clips);  in read_samples()
171 static size_t write_samples(sox_format_t * ft, const sox_sample_t *buf, size_t len)  in write_samples()  argument
173   priv_t * lpc = (priv_t *)ft->priv;  in write_samples()
176   while (len > 0) {  in write_samples()
177     while (len > 0 && lpc->samples < LPC10_SAMPLES_PER_FRAME) {  in write_samples()
179       lpc->speech[lpc->samples++] = SOX_SAMPLE_TO_FLOAT_32BIT(buf[nwritten++], ft->clips);  in write_samples()
180       len--;  in write_samples()
183     if (lpc->samples == LPC10_SAMPLES_PER_FRAME) {  in write_samples()
186       lpc10_encode(lpc->speech, bits, lpc->encst);  in write_samples()
188       lpc->samples = 0;  in write_samples()
197   priv_t * lpc = (priv_t *)ft->priv;  in stopread()
199   free(lpc->decst);  in stopread()
206   priv_t * lpc = (priv_t *)ft->priv;  in stopwrite()
208   free(lpc->encst);  in stopwrite()