linx-simulator2/node_modules/lame/deps/mpg123/doc/examples/extract_frames.c
2019-09-18 11:11:16 +03:00

93 lines
2.5 KiB
C

/*
extract_frams: utlize the framebyframe API and mpg123_framedata to extract the MPEG frames out of a stream (strip off anything else).
copyright 2011 by the mpg123 project - free software under the terms of the LGPL 2.1
see COPYING and AUTHORS files in distribution or http://mpg123.org
initially written by Thomas Orgis
*/
#include <mpg123.h>
/* unistd.h is not available under MSVC,
io.h defines the read and write functions */
#ifndef _MSC_VER
#include <unistd.h>
#else
#include <io.h>
#endif
#include <stdio.h>
int do_work(mpg123_handle *m);
int main(int argc, char **argv)
{
int ret = 0;
mpg123_handle *m;
mpg123_init();
m = mpg123_new(NULL, &ret);
if(m == NULL)
{
fprintf(stderr, "Cannot create handle: %s", mpg123_plain_strerror(ret));
}
else
{
fprintf(stderr, "I'll take your dirty MPEG audio from standard input and will write the extrated pure MPEG data to stadard output.\n");
if(argc > 1 && strcmp(argv[1], "--noinfo") == 0)
{
fprintf(stderr, "Enabling parsing/consuming of the Info frame so that it will not appear in output.\n");
ret = mpg123_param(m, MPG123_REMOVE_FLAGS, MPG123_IGNORE_INFOFRAME, 0.);
}
else
{
fprintf(stderr, "If you'd have given --noinfo as argument, I would omit a LAME/Xing info frame.\n");
ret = mpg123_param(m, MPG123_ADD_FLAGS, MPG123_IGNORE_INFOFRAME, 0.);
}
if(ret == 0) ret = do_work(m);
if(ret != 0) fprintf(stderr, "Some error occured: %s\n", mpg123_strerror(m));
mpg123_delete(m); /* Closes, too. */
}
mpg123_exit();
return ret;
}
int do_work(mpg123_handle *m)
{
int ret;
size_t count = 0;
ret = mpg123_open_fd(m, STDIN_FILENO);
if(ret != MPG123_OK) return ret;
while( (ret = mpg123_framebyframe_next(m)) == MPG123_OK || ret == MPG123_NEW_FORMAT )
{
unsigned long header;
unsigned char *bodydata;
size_t bodybytes;
if(mpg123_framedata(m, &header, &bodydata, &bodybytes) == MPG123_OK)
{
/* Need to extract the 4 header bytes from the native storage in the correct order. */
unsigned char hbuf[4];
int i;
for(i=0; i<4; ++i) hbuf[i] = (unsigned char) ((header >> ((3-i)*8)) & 0xff);
/* Now write out both header and data, fire and forget. */
write(STDOUT_FILENO, hbuf, 4);
write(STDOUT_FILENO, bodydata, bodybytes);
fprintf(stderr, "%zu: header 0x%08x, %zu body bytes\n", ++count, header, bodybytes);
}
}
if(ret != MPG123_DONE)
fprintf(stderr, "Some error occured (non-fatal?): %s\n", mpg123_strerror(m));
fprintf(stderr, "Done with %zu MPEG frames.\n", count);
return 0;
}