FreeCalypso > hg > gsm-codec-lib
view miscutil/amrts-pcm8-compact.c @ 477:4c9222d95647
libtwamr encoder: always emit frame->mode = mode;
In the original implementation of amr_encode_frame(), the 'mode' member
of the output struct was set to 0xFF if the output frame type is TX_NO_DATA.
This design was made to mimic the mode field (16-bit word) being set to
0xFFFF (or -1) in 3GPP test sequence format - but nothing actually depends
on this struct member being set in any way, and amr_frame_to_tseq()
generates the needed 0xFFFF on its own, based on frame->type being equal
to TX_NO_DATA.
It is simpler and more efficient to always set frame->mode to the actual
encoding mode in amr_encode_frame(), and this new behavior has already
been documented in doc/AMR-library-API description in anticipation of
the present change.
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Sat, 18 May 2024 22:30:42 +0000 |
parents | 7c50864deaff |
children |
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/* * The set of AMR test sequences shipped by 3GPP as TS 26.074 includes * not only linear PCM (13-bit left-justified) and AMR-encoded files, * but also 8-bit PCM sequences in both A-law and mu-law. However, * those PCM8 sequences are shipped in a stupid and inconvenient format: * each 8-bit PCM sample is expanded to a 16-bit word, written in LE * byte order. This utility converts a PCM8 test sequence file * from this weird format into sane PCM8 format with one byte per sample. * For this conversion, it does not matter whether the PCM8 test sequence * in question is A-law or mu-law. */ #include <stdio.h> #include <stdlib.h> main(argc, argv) char **argv; { FILE *inf, *outf; int cdat, cpad; if (argc != 3) { fprintf(stderr, "usage: %s in-file out-file\n", argv[0]); exit(1); } inf = fopen(argv[1], "r"); if (!inf) { perror(argv[1]); exit(1); } outf = fopen(argv[2], "w"); if (!outf) { perror(argv[2]); exit(1); } for (;;) { cdat = getc(inf); if (cdat < 0) break; cpad = getc(inf); if (cpad < 0) { fprintf(stderr, "error: %s has odd length\n", argv[1]); exit(1); } if (cpad != 0) { fprintf(stderr, "error: presumed padding byte in %s is not 0\n", argv[1]); exit(1); } putc(cdat, outf); } fclose(outf); exit(0); }