GStreamer application to convert a .ogg file to an .mp4 file

Stefan Kost ensonic at hora-obscura.de
Sun Jun 5 14:18:55 PDT 2011


Am 03.06.2011 23:41, schrieb William Metcalf:
> I am writing an application to convert a .ogg file to an .mp4 file.  My code is
> below.  I already have the terminal pipeline for completing this task, and I am
> just trying to convert the terminal pipeline into an actual c program.  The
> pipeline seems correct to be, but when I run the application I get an error
> "Internal data stream error".  Does anyone have any suggestions as to what is
> wrong with my code?  Thank you in advance.

Have a look at the debug log. You could also add a:
GST_DEBUG_BIN_TO_DOT_FILE(pipeline, GST_DEBUG_GRAPH_SHOW_ALL, "myconverter") to
the GST_MESSAGE_ERROR handler below and run your app using
GST_DEBUG_DUMP_DOT_DIR=c:\\ myconverter
This should get you a pipeline graph in dot formant, taht you can render to
svg/png/.. using graphviz dot tool. There you can e.g. see easily between which
elements pads are not negotiated, not linked, etc.

Stefan

> 
> #include<gst\gst.h>
> #include<glib-2.0\glib.h>
> #include<string.h>
> #include"Encode_File_Test.h"
> #include"Preprocessor_Defines.h"
> 
> /* Handle messages from the pipeline bus */
> 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;
> }
> 
> /* Handles when a pad is added to the demuxer */
> static void on_pad_added(GstElement *element, GstPad *pad, gpointer data)
> {
>     guint result;
>     GstPad *sinkpad;
>     gchar* name;
>     name = gst_pad_get_name(pad);
> 
>     result = g_strcasecmp(name, "serial_1fa82364");
>     /* This is the audio pad of the demuxer we need to link it to the decoder's
> audio output in the queue */
>     if(!result)
>     {
>         /* We can now link this pad with the audio decoder's sink pad */
>         g_print("Dynamic pad created, linking the demuxer to the audio decoder\n");
> 
>         sinkpad = gst_element_get_pad(audio_queue, "sink");
> 
>         gst_pad_link(pad, sinkpad);
> 
>         gst_object_unref(sinkpad);
>     }
> 
>     result = g_strcasecmp(name, "serial_0f0678e1");
>     /* This is the video pad of the demuxer we need to link it to the decoder's
> video output in the queue */
>     if(!result)
>     {
> 
>         /* We can now link this pad with the video decoder's sink pad */
>         g_print("Dynamic pad created, linking the demuxer to the video decoder\n");
> 
>         sinkpad = gst_element_get_static_pad(video_queue, "sink");
> 
>         gst_pad_link(pad, sinkpad);
> 
>         gst_object_unref(sinkpad);
>     }
> }
> 
> /* Connects the src pad of the audio out queue to the audio sink pad of the
> mxuer */
> static void link_audio_to_multiplexer(GstElement *audio_output, GstElement *muxer)
> {
>     GstPad *pad, *link_pad;
> 
>     link_pad = gst_element_get_static_pad(audio_output, "src");
> 
>     pad = gst_element_get_request_pad(muxer, "audio_%d");
> 
>     gst_pad_link(link_pad, pad);
> 
>     gst_object_unref(pad);
> }
> 
> /* Connects the src pad of the video out queue to the video sink pad of the
> muxer */
> static void link_video_to_multiplexer(GstElement *video_output, GstElement *muxer)
> {
>     GstPad *pad, *link_pad;
> 
>     link_pad = gst_element_get_static_pad(video_output, "src");
> 
>     pad = gst_element_get_request_pad(muxer, "video_%d");
> 
>     gst_pad_link(link_pad, pad);
> 
>     gst_object_unref(pad);
> }
> 
> int main (int argc, char *argv[])
> {
>     gst_init(&argc, &argv);
> 
>     loop = g_main_loop_new(NULL, FALSE);
> 
>     /* Create elements */
>     pipeline            = gst_pipeline_new("audio-player");
> 
>     /* Element for reading in a file */
>     source                = gst_element_factory_make("filesrc", "file-source");
> 
>     /* OGG elements */
>     oggdemuxer            = gst_element_factory_make("oggdemux", "ogg-demuxer");
>     vorbis_decoder        = gst_element_factory_make("vorbisdec",
> "vorbis-decoder");
>     theora_decoder        = gst_element_factory_make("theoradec",
> "theora-decoder");
> 
>     /* MP4 elements */
>     audio_encoder        = gst_element_factory_make("faac", "aac-encoder");
>     video_encoder        = gst_element_factory_make("ffenc_mpeg4", "avc-encoder");
>     mp4_muxer            = gst_element_factory_make("qtmux", "mp4-muxer");
> 
>     /* Audio Video elements */
>     audio_converter        = gst_element_factory_make("audioconvert",
> "audio-converter");
>     video_converter        = gst_element_factory_make("ffmpegcolorspace",
> "video-converter");
>     audio_resample        = gst_element_factory_make("audioresample",
> "audio-resample");
>     audio_rate            = gst_element_factory_make("audiorate", "audio-rate");
>     videosink            = gst_element_factory_make("autovideosink", "video-sink");
>     audiosink            = gst_element_factory_make("autoaudiosink", "audio-sink");
> 
>     /* Queues */
>     video_queue            = gst_element_factory_make("queue", "video-queue");
>     audio_queue            = gst_element_factory_make("queue", "audio-queue");
>     video_out_queue        = gst_element_factory_make("queue", "video-out-queue");
>     audio_out_queue        = gst_element_factory_make("queue", "audio-out-queue");
> 
>     /* Element to write to the file */
>     filesink                = gst_element_factory_make("filesink", "file-sink");
> 
>     /* Make sure we were able to create all of the elements*/
>     if(!pipeline || !source || !oggdemuxer || !vorbis_decoder || !theora_decoder
> || !audio_encoder || !video_encoder || !mp4_muxer || !audio_converter ||
> !video_converter || !audio_resample || !audio_rate || !videosink || !audiosink
> || !video_queue || !audio_queue || !video_out_queue || !audio_out_queue ||
> !filesink )
>     {
>         g_printerr("One ore more elements could not be created. Exiting.\n");
>         return -1;
>     }
> 
>     /* Input file */
>     g_object_set(G_OBJECT(source), "location", "c:\\video.ogg", NULL);
>     g_object_set(G_OBJECT(filesink), "location", "c:\\video(encoded from
> ogg).mp4", NULL);
> 
>     /* Add a message handler from pipeline bus */
>     bus = gst_pipeline_get_bus(GST_PIPELINE(pipeline));
>     gst_bus_add_watch(bus, bus_call, loop);
>     gst_object_unref(bus);
> 
>     /* add elements to the pipeline */
>     gst_bin_add_many(GST_BIN(pipeline), source, oggdemuxer, video_queue,
> theora_decoder, video_converter, video_encoder, video_out_queue, audio_queue,
> vorbis_decoder, audio_converter, audio_encoder, audio_out_queue, mp4_muxer,
> filesink, NULL);
> 
>     /* link the elements together */
>     gst_element_link(source, oggdemuxer);
> 
>     /* video_queue -> theoradec -> ffmpegcolorspace -> ffenc_mpeg4 ->
> video_out_queue ~> qtmux */
>     res = gst_element_link_many(video_queue, theora_decoder, video_converter,
> video_encoder, video_out_queue, NULL);
>     if(!res)
>     {
>         g_printerr("There was a problem linking video elements.\n");
>         return 1;
>     }
> 
>     /* queue_audio -> vorbisdec -> audioconvert -> faac -> audio_out_queue ~>
> qtmux */
>     res = gst_element_link_many(audio_queue, vorbis_decoder, audio_converter,
> audio_encoder, audio_out_queue, NULL);
>     if(!res)
>     {
>         g_printerr("There was a problem linking elements.\n");
>         return 1;
>     }
>     g_signal_connect(oggdemuxer, "pad-added", G_CALLBACK(on_pad_added), NULL);
> 
>     /* qtmux -> filesink */
>     res = gst_element_link(mp4_muxer, filesink);
> 
>     link_video_to_multiplexer(video_out_queue, mp4_muxer);
>     link_audio_to_multiplexer(audio_out_queue, mp4_muxer);
> 
> 
>     /* Set the pipeline stat to play and start the main loop*/
>     g_print("Starting the pipeline\n");
>     gst_element_set_state(pipeline, GST_STATE_PLAYING);
>     g_main_loop_run(loop);
> 
>     /* We are done now, do a little bit of cleaning up */
>     g_print("Stopping the pipeline.\n");
>     gst_element_set_state(pipeline, GST_STATE_NULL);
>     gst_object_unref(GST_OBJECT(pipeline));
> 
>     return 0;
> }
> _______________________________________________
> gstreamer-devel mailing list
> gstreamer-devel at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel



More information about the gstreamer-devel mailing list