FreeCalypso > hg > freecalypso-tools
diff tchtools/efr2dsp.c @ 906:94890123a74f
tchtools: new program fc-efr2tch
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Wed, 28 Dec 2022 10:05:46 +0000 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/tchtools/efr2dsp.c Wed Dec 28 10:05:46 2022 +0000 @@ -0,0 +1,75 @@ +/* + * The utility function implemented in this module constructs a 33-byte + * frame for loading into Calypso DSP TCH UL buffer from a standard + * 244-bit EFR codec frame in the RTP encoding format of ETSI TS 101 318. + */ + +#include <sys/types.h> +#include <string.h> +#include <strings.h> + +static const u_short efr_to_tidsp_table[244] = { + 50, 24, 25, 37, 38, 43, 44, 26, 42, 27, 39, 40, + 45, 51, 52, 41, 46, 28, 29, 47, 53, 77, 78, 30, + 54, 55, 79, 56, 80, 109, 110, 111, 112, 113, 114, 115, + 180, 181, 0, 1, 2, 3, 4, 5, 20, 31, 32, 16, + 73, 105, 157, 81, 118, 138, 165, 82, 119, 139, 166, 83, + 120, 140, 167, 84, 121, 141, 168, 85, 122, 186, 200, 204, + 224, 244, 205, 225, 245, 206, 226, 246, 207, 227, 247, 208, + 228, 248, 17, 61, 101, 153, 161, 12, 13, 22, 35, 48, + 116, 18, 74, 106, 158, 86, 123, 142, 169, 87, 124, 143, + 170, 88, 125, 144, 171, 89, 126, 145, 172, 90, 127, 189, + 201, 209, 229, 249, 210, 230, 250, 211, 231, 251, 212, 232, + 252, 213, 233, 253, 19, 62, 102, 154, 162, 6, 7, 8, + 9, 10, 11, 21, 33, 34, 57, 75, 107, 159, 91, 128, + 146, 173, 92, 129, 147, 174, 93, 130, 148, 175, 94, 131, + 149, 176, 95, 132, 192, 202, 214, 234, 254, 215, 235, 255, + 216, 236, 256, 217, 237, 257, 218, 238, 258, 59, 63, 103, + 155, 163, 14, 15, 23, 36, 49, 117, 58, 76, 108, 160, + 96, 133, 150, 177, 97, 134, 198, 199, 98, 135, 151, 178, + 99, 136, 152, 179, 100, 137, 195, 203, 219, 239, 259, 220, + 240, 260, 221, 241, 261, 222, 242, 262, 223, 243, 263, 60, + 64, 104, 156, 164 +}; + +static int +msb_get_bit(buf, bn) + u_char *buf; +{ + int pos_byte = bn >> 3; + int pos_bit = 7 - (bn & 7); + + return (buf[pos_byte] >> pos_bit) & 1; +} + +static void +msb_set_bit(buf, bn) + u_char *buf; +{ + int pos_byte = bn >> 3; + int pos_bit = 7 - (bn & 7); + + buf[pos_byte] |= (1 << pos_bit); +} + +void +efr_std_to_tidsp(inbytes, outbytes) + u_char *inbytes, *outbytes; +{ + int i; + + bzero(outbytes, 33); + for (i = 0; i < 244; i++) { + if (msb_get_bit(inbytes, i + 4)) + msb_set_bit(outbytes, efr_to_tidsp_table[i]); + } + /* set repetition bits */ + if (outbytes[23] & 0x20) + outbytes[23] |= 0x18; + if (outbytes[23] & 0x04) + outbytes[23] |= 0x03; + if (outbytes[24] & 0x80) + outbytes[24] |= 0x60; + if (outbytes[24] & 0x10) + outbytes[24] |= 0x0C; +}