FreeCalypso > hg > gsm-codec-lib
view amrconv/ietf-parse.c @ 427:357d1faad55d
libtwamr: implement decoder top level
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Tue, 07 May 2024 21:45:47 +0000 |
parents | 934cf92a1c45 |
children |
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/* * This program reads an AMR recording in IETF RFC 4867 format and parses it * into a human-readable form. */ #include <stdio.h> #include <stdint.h> #include <stdlib.h> #include <string.h> #include <strings.h> #include "amr_defs.h" extern char *amr_mode_names[16]; extern const char amr_file_hdr[IETF_HDR_LEN]; extern const uint8_t extra_bytes_per_ft[9]; main(argc, argv) char **argv; { char *infname; FILE *inf; uint8_t frm_in[MAX_IF1_BYTES]; unsigned frame_no, mode, qbit, sti, sid_mode; uint8_t ser_bits[MAX_SERIAL_SIZE]; uint16_t params[MAX_PRM_SIZE]; int rc; if (argc != 2) { fprintf(stderr, "usage: %s amr_file\n", argv[0]); exit(1); } infname = argv[1]; inf = fopen(infname, "r"); if (!inf) { perror(infname); exit(1); } if (fread(frm_in, 1, IETF_HDR_LEN, inf) != IETF_HDR_LEN || bcmp(frm_in, amr_file_hdr, IETF_HDR_LEN)) { fprintf(stderr, "error: %s is not in IETF AMR format\n", infname); exit(1); } for (frame_no = 0; ; frame_no++) { rc = getc(inf); if (rc < 0) break; mode = (rc & 0x78) >> 3; qbit = (rc & 4) >> 2; printf("#%u: FT=%u (%s) Q=%u\n", frame_no, mode, amr_mode_names[mode], qbit); if (mode == MODE_NO_DATA) continue; if (mode > MRDTX) { fprintf(stderr, "error in frame #%u: invalid FT=%u\n", frame_no, mode); exit(1); } rc = fread(frm_in, 1, extra_bytes_per_ft[mode], inf); if (rc != extra_bytes_per_ft[mode]) { fprintf(stderr, "error: short read from %s on frame #%u\n", infname, frame_no); exit(1); } amr_if1_unpack(frm_in, ser_bits, mode); reassemble_amr_params(ser_bits, params, mode); dump_amr_params(params, mode); if (mode == MRDTX) { sti = (frm_in[4] & 0x10) >> 4; sid_mode = 0; if (frm_in[4] & 0x08) sid_mode |= 1; if (frm_in[4] & 0x04) sid_mode |= 2; if (frm_in[4] & 0x02) sid_mode |= 4; printf(" SID_%s Mode=%u\n", sti ? "UPDATE" : "FIRST", sid_mode); } } exit(0); }