First execute LTIB (./ltib -c) and select these packages: all gstreamer plugin, alsa-utils and libmad. Create your file code (i.e.: playmp3.c):
#include <gst/gst.h>
#include <glib.h>
static gboolean bus_call (GstBus *bus, GstMessage *msg, gpointer data) { GMainLoop *loop = (GMainLoop *) data; switch (GST_MESSAGE_TYPE (msg)) { case GST_MESSAGE_EOS: g_print ("End of stream\n"); g_main_loop_quit (loop); break; case GST_MESSAGE_ERROR: { gchar *debug; GError *error; gst_message_parse_error (msg, &error, &debug); g_free (debug); g_printerr ("Error: %s\n", error->message); g_error_free (error); g_main_loop_quit (loop); break; } default: break; } return TRUE; } int main (int argc, char *argv[]) { GMainLoop *loop; GstElement *pipeline, *source, *decoder, *conv, *resample, *sink; GstBus *bus; /* Initialisation */ gst_init (&argc, &argv); loop = g_main_loop_new (NULL, FALSE); /* Check input arguments */ if (argc != 2) { g_printerr ("Usage: %s <MP3 filename>\n", argv[0]); return -1; } /* Create gstreamer elements */ pipeline = gst_pipeline_new ("audio-player"); source = gst_element_factory_make ("filesrc", "file-source"); decoder = gst_element_factory_make ("mad", "mp3-decoder"); conv = gst_element_factory_make ("audioconvert", "converter"); resample = gst_element_factory_make ("audioresample", "audio-resample"); sink = gst_element_factory_make ("autoaudiosink", "audio-output"); if (!pipeline || !source || !decoder || !conv || !resample || !sink) { g_printerr ("One element could not be created. Exiting.\n"); return -1; } /* Set up the pipeline */ /* we set the input filename to the source element */ g_object_set (G_OBJECT (source), "location", argv[1], NULL); /* we add a message handler */ bus = gst_pipeline_get_bus (GST_PIPELINE (pipeline)); gst_bus_add_watch (bus, bus_call, loop); gst_object_unref (bus); /* we add all elements into the pipeline */ /* file-source | mp3-decoder | converter | resample | alsa-output */ gst_bin_add_many (GST_BIN (pipeline), source, decoder, conv, resample, sink, NULL); /* we link the elements together */ /* file-source -> mp3-decoder -> converter -> resample -> alsa-output */ gst_element_link_many (source, decoder, conv, sink, NULL); /* Set the pipeline to "playing" state*/ g_print ("Now playing: %s\n", argv[1]); gst_element_set_state (pipeline, GST_STATE_PLAYING); /* Iterate */ g_print ("Running...\n"); g_main_loop_run (loop); /* Out of the main loop, clean up nicely */ g_print ("Returned, stopping playback\n"); gst_element_set_state (pipeline, GST_STATE_NULL); g_print ("Deleting pipeline\n"); gst_object_unref (GST_OBJECT (pipeline)); return 0; }
Create a directory inside your ltib directory to compile your source code: $ mkdir ~/your-ltib-dir/rpm/BUILD/gst
Enter on LTIB shell mode: $ ./ltib -m shell
Entering ltib shell mode, type 'exit' to quit LTIB>
Enter in your application dir: LTIB> cd rpm/BUILD/gst/
Compile your application: LTIB> gcc -Wall $(pkg-config --cflags --libs gstreamer-0.10) playmp3.c -o playmp3
If everything worked file you will get a "playmp3" arm binary:
LTIB> file playmp3 playmp3: ELF 32-bit LSB executable, ARM, version 1 (SYSV), for GNU/Linux 2.6.14, dynamically linked (uses shared libs), not stripped
Now just copy it to ~/your-ltib-dir/rootfs/home. Start your board using this rootfs and execute:
root@freescale ~$ cd /home/ root@freescale /home$ ./playmp3 your-file.mp3 Now playing: your-file.mp3 Running...
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