1 /*
2 extract_frams: utlize the framebyframe API and mpg123_framedata to extract the MPEG frames out of a stream (strip off anything else).
3
4 copyright 2011-2013 by the mpg123 project - free software under the terms of the LGPL 2.1
5 see COPYING and AUTHORS files in distribution or http://mpg123.org
6 initially written by Thomas Orgis
7 */
8
9 #include "config.h"
10 #include "compat.h"
11 #include <mpg123.h>
12
13 #include "getlopt.h"
14
15
16 static struct
17 {
18 int info;
19 long icy_interval;
20 int verbose;
21 } param =
22 {
23 TRUE
24 ,0
25 ,0
26 };
27
28 static const char* progname;
29
usage(int err)30 static void usage(int err)
31 {
32 FILE* o = stdout;
33 if(err)
34 {
35 o = stderr;
36 fprintf(o, "You made some mistake in program usage... let me briefly remind you:\n\n");
37 }
38 fprintf(o, "Extract only MPEG frames from a stream using libmpg123 (stdin to stdout)\n");
39 fprintf(o, "\tversion %s; written and copyright by Thomas Orgis and the mpg123 project\n", PACKAGE_VERSION);
40 fprintf(o,"\nusage: %s [option(s)] < input > output\n", progname);
41 fprintf(o,"\noptions:\n");
42 fprintf(o," -h --help give usage help\n");
43 fprintf(o," -i <n> --icy-interval <n> stream has ICY metadata present with this interval\n");
44 fprintf(o," -n --no-info also strip info frame at beginning\n");
45 fprintf(o," -v[*] --verbose increase verbosity level\n");
46 exit(err);
47 }
48
want_usage(char * bla)49 static void want_usage(char* bla)
50 {
51 usage(0);
52 }
53
set_verbose(char * arg)54 static void set_verbose (char *arg)
55 {
56 param.verbose++;
57 }
58
59 static topt opts[] =
60 {
61 {'h', "help", 0, want_usage, 0, 0}
62 ,{'i', "icy-interval", GLO_ARG|GLO_LONG, 0, ¶m.icy_interval, 0}
63 ,{'n', "no-info", GLO_INT, 0, ¶m.info, FALSE}
64 ,{'v', "verbose", 0, set_verbose, 0, 0}
65 ,{0, 0, 0, 0, 0, 0}
66 };
67
68 int do_work(mpg123_handle *m);
69
main(int argc,char ** argv)70 int main(int argc, char **argv)
71 {
72 int ret = 0;
73 mpg123_handle *m;
74
75 progname = argv[0];
76
77 while ((ret = getlopt(argc, argv, opts)))
78 switch (ret) {
79 case GLO_UNKNOWN:
80 fprintf (stderr, "%s: Unknown option \"%s\".\n",
81 progname, loptarg);
82 usage(1);
83 case GLO_NOARG:
84 fprintf (stderr, "%s: Missing argument for option \"%s\".\n",
85 progname, loptarg);
86 usage(1);
87 }
88
89 mpg123_init();
90 m = mpg123_new(NULL, &ret);
91
92 if(m == NULL)
93 {
94 fprintf(stderr, "Cannot create handle: %s", mpg123_plain_strerror(ret));
95 }
96 else
97 {
98 ret = mpg123_param(m, MPG123_VERBOSE, param.verbose, 0.);
99 if(ret == MPG123_OK)
100 {
101 if(param.verbose)
102 fprintf(stderr, "Info frame handling: %s\n",
103 param.info ? "pass-through" : "remove");
104 ret = param.info /* If info frame is ignored, it is treated as MPEG data. */
105 ? mpg123_param(m, MPG123_ADD_FLAGS, MPG123_IGNORE_INFOFRAME, 0.)
106 : mpg123_param(m, MPG123_REMOVE_FLAGS, MPG123_IGNORE_INFOFRAME, 0.);
107 }
108 if(ret == MPG123_OK && param.icy_interval > 0)
109 {
110 if(param.verbose) fprintf(stderr, "ICY interval: %li\n", param.icy_interval);
111 ret = mpg123_param(m, MPG123_ICY_INTERVAL, param.icy_interval, 0);
112 }
113
114 if(ret == MPG123_OK) ret = do_work(m);
115
116 if(ret != MPG123_OK) fprintf(stderr, "Some error occured: %s\n", mpg123_strerror(m));
117
118 mpg123_delete(m); /* Closes, too. */
119 }
120 mpg123_exit();
121
122 return ret;
123 }
124
do_work(mpg123_handle * m)125 int do_work(mpg123_handle *m)
126 {
127 int ret;
128 size_t count = 0;
129 ret = mpg123_open_fd(m, STDIN_FILENO);
130 if(ret != MPG123_OK) return ret;
131
132 while( (ret = mpg123_framebyframe_next(m)) == MPG123_OK || ret == MPG123_NEW_FORMAT )
133 {
134 unsigned long header;
135 unsigned char *bodydata;
136 size_t bodybytes;
137 if(mpg123_framedata(m, &header, &bodydata, &bodybytes) == MPG123_OK)
138 {
139 /* Need to extract the 4 header bytes from the native storage in the correct order. */
140 unsigned char hbuf[4];
141 int i;
142 for(i=0; i<4; ++i) hbuf[i] = (unsigned char) ((header >> ((3-i)*8)) & 0xff);
143
144 /* Now write out both header and data, fire and forget. */
145 write(STDOUT_FILENO, hbuf, 4);
146 write(STDOUT_FILENO, bodydata, bodybytes);
147 if(param.verbose)
148 fprintf(stderr, "%"SIZE_P": header 0x%08lx, %"SIZE_P" body bytes\n"
149 , (size_p)++count, header, (size_p)bodybytes);
150 }
151 }
152
153 if(ret != MPG123_DONE)
154 fprintf(stderr, "Some error occured (non-fatal?): %s\n", mpg123_strerror(m));
155
156 if(param.verbose) fprintf(stderr, "Done with %"SIZE_P" MPEG frames.\n"
157 , (size_p)count);
158
159 return MPG123_OK;
160 }
161