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-rw-r--r--src/libmad/minimad.c222
1 files changed, 0 insertions, 222 deletions
diff --git a/src/libmad/minimad.c b/src/libmad/minimad.c
index ac412ae4..e69de29b 100644
--- a/src/libmad/minimad.c
+++ b/src/libmad/minimad.c
@@ -1,222 +0,0 @@
-/*
- * libmad - MPEG audio decoder library
- * Copyright (C) 2000-2004 Underbit Technologies, Inc.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
- * $Id: minimad.c,v 1.4 2004/01/23 09:41:32 rob Exp $
- */
-
-# include <stdio.h>
-# include <unistd.h>
-# include <sys/stat.h>
-# include <sys/mman.h>
-
-# include "mad.h"
-
-/*
- * This is perhaps the simplest example use of the MAD high-level API.
- * Standard input is mapped into memory via mmap(), then the high-level API
- * is invoked with three callbacks: input, output, and error. The output
- * callback converts MAD's high-resolution PCM samples to 16 bits, then
- * writes them to standard output in little-endian, stereo-interleaved
- * format.
- */
-
-static int decode(unsigned char const *, unsigned long);
-
-int main(int argc, char *argv[])
-{
- struct stat stat;
- void *fdm;
-
- if (argc != 1)
- return 1;
-
- if (fstat(STDIN_FILENO, &stat) == -1 ||
- stat.st_size == 0)
- return 2;
-
- fdm = mmap(0, stat.st_size, PROT_READ, MAP_SHARED, STDIN_FILENO, 0);
- if (fdm == MAP_FAILED)
- return 3;
-
- decode(fdm, stat.st_size);
-
- if (munmap(fdm, stat.st_size) == -1)
- return 4;
-
- return 0;
-}
-
-/*
- * This is a private message structure. A generic pointer to this structure
- * is passed to each of the callback functions. Put here any data you need
- * to access from within the callbacks.
- */
-
-struct buffer {
- unsigned char const *start;
- unsigned long length;
-};
-
-/*
- * This is the input callback. The purpose of this callback is to (re)fill
- * the stream buffer which is to be decoded. In this example, an entire file
- * has been mapped into memory, so we just call mad_stream_buffer() with the
- * address and length of the mapping. When this callback is called a second
- * time, we are finished decoding.
- */
-
-static
-enum mad_flow input(void *data,
- struct mad_stream *stream)
-{
- struct buffer *buffer = data;
-
- if (!buffer->length)
- return MAD_FLOW_STOP;
-
- mad_stream_buffer(stream, buffer->start, buffer->length);
-
- buffer->length = 0;
-
- return MAD_FLOW_CONTINUE;
-}
-
-/*
- * The following utility routine performs simple rounding, clipping, and
- * scaling of MAD's high-resolution samples down to 16 bits. It does not
- * perform any dithering or noise shaping, which would be recommended to
- * obtain any exceptional audio quality. It is therefore not recommended to
- * use this routine if high-quality output is desired.
- */
-
-static inline
-signed int scale(mad_fixed_t sample)
-{
- /* round */
- sample += (1L << (MAD_F_FRACBITS - 16));
-
- /* clip */
- if (sample >= MAD_F_ONE)
- sample = MAD_F_ONE - 1;
- else if (sample < -MAD_F_ONE)
- sample = -MAD_F_ONE;
-
- /* quantize */
- return sample >> (MAD_F_FRACBITS + 1 - 16);
-}
-
-/*
- * This is the output callback function. It is called after each frame of
- * MPEG audio data has been completely decoded. The purpose of this callback
- * is to output (or play) the decoded PCM audio.
- */
-
-static
-enum mad_flow output(void *data,
- struct mad_header const *header,
- struct mad_pcm *pcm)
-{
- unsigned int nchannels, nsamples;
- mad_fixed_t const *left_ch, *right_ch;
-
- /* pcm->samplerate contains the sampling frequency */
-
- nchannels = pcm->channels;
- nsamples = pcm->length;
- left_ch = pcm->samples[0];
- right_ch = pcm->samples[1];
-
- while (nsamples--) {
- signed int sample;
-
- /* output sample(s) in 16-bit signed little-endian PCM */
-
- sample = scale(*left_ch++);
- putchar((sample >> 0) & 0xff);
- putchar((sample >> 8) & 0xff);
-
- if (nchannels == 2) {
- sample = scale(*right_ch++);
- putchar((sample >> 0) & 0xff);
- putchar((sample >> 8) & 0xff);
- }
- }
-
- return MAD_FLOW_CONTINUE;
-}
-
-/*
- * This is the error callback function. It is called whenever a decoding
- * error occurs. The error is indicated by stream->error; the list of
- * possible MAD_ERROR_* errors can be found in the mad.h (or stream.h)
- * header file.
- */
-
-static
-enum mad_flow error(void *data,
- struct mad_stream *stream,
- struct mad_frame *frame)
-{
- struct buffer *buffer = data;
-
- fprintf(stderr, "decoding error 0x%04x (%s) at byte offset %u\n",
- stream->error, mad_stream_errorstr(stream),
- stream->this_frame - buffer->start);
-
- /* return MAD_FLOW_BREAK here to stop decoding (and propagate an error) */
-
- return MAD_FLOW_CONTINUE;
-}
-
-/*
- * This is the function called by main() above to perform all the decoding.
- * It instantiates a decoder object and configures it with the input,
- * output, and error callback functions above. A single call to
- * mad_decoder_run() continues until a callback function returns
- * MAD_FLOW_STOP (to stop decoding) or MAD_FLOW_BREAK (to stop decoding and
- * signal an error).
- */
-
-static
-int decode(unsigned char const *start, unsigned long length)
-{
- struct buffer buffer;
- struct mad_decoder decoder;
- int result;
-
- /* initialize our private message structure */
-
- buffer.start = start;
- buffer.length = length;
-
- /* configure input, output, and error functions */
-
- mad_decoder_init(&decoder, &buffer,
- input, 0 /* header */, 0 /* filter */, output,
- error, 0 /* message */);
-
- /* start decoding */
-
- result = mad_decoder_run(&decoder, MAD_DECODER_MODE_SYNC);
-
- /* release the decoder */
-
- mad_decoder_finish(&decoder);
-
- return result;
-}