| /* GStreamer |
| * |
| * appsrc-seekable.c: example for using appsrc in seekable mode. |
| * |
| * Copyright (C) 2008 Wim Taymans <wim.taymans@gmail.com> |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Library General Public |
| * License as published by the Free Software Foundation; either |
| * version 2 of the License, or (at your option) any later version. |
| * |
| * This library 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 |
| * Library General Public License for more details. |
| * |
| * You should have received a copy of the GNU Library General Public |
| * License along with this library; if not, write to the |
| * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, |
| * Boston, MA 02110-1301, USA. |
| */ |
| |
| #ifdef HAVE_CONFIG_H |
| #include "config.h" |
| #endif |
| |
| #include <gst/gst.h> |
| |
| #include <stdio.h> |
| #include <string.h> |
| #include <stdlib.h> |
| |
| GST_DEBUG_CATEGORY (appsrc_playbin_debug); |
| #define GST_CAT_DEFAULT appsrc_playbin_debug |
| |
| /* |
| * an example application of using appsrc in seekable mode. When the |
| * appsrc requests data with the need-data signal, we retrieve a buffer and |
| * push it to appsrc. We can also use the method as demonstrated in |
| * appsrc-stream.c, ie. pushing buffers when we can. |
| * |
| * This is a good example how one would deal with a remote http server that |
| * supports range requests. |
| * |
| * Appsrc in seekable mode needs seeking support and we must thus connect |
| * to the seek signal to perform any seeks when requested. |
| * |
| * In seekable mode we should set the size of the source material. |
| */ |
| typedef struct _App App; |
| |
| struct _App |
| { |
| GstElement *playbin; |
| GstElement *appsrc; |
| |
| GMainLoop *loop; |
| |
| GMappedFile *file; |
| guint8 *data; |
| gsize length; |
| guint64 offset; |
| }; |
| |
| App s_app; |
| |
| #define CHUNK_SIZE 4096 |
| |
| /* This method is called by the need-data signal callback, we feed data into the |
| * appsrc with an arbitrary size. |
| */ |
| static void |
| feed_data (GstElement * appsrc, guint size, App * app) |
| { |
| GstBuffer *buffer; |
| guint len; |
| GstFlowReturn ret; |
| |
| if (app->offset >= app->length) { |
| /* we are EOS, send end-of-stream */ |
| g_signal_emit_by_name (app->appsrc, "end-of-stream", &ret); |
| return; |
| } |
| |
| /* read any amount of data, we are allowed to return less if we are EOS */ |
| buffer = gst_buffer_new (); |
| |
| len = CHUNK_SIZE; |
| if (app->offset + len > app->length) |
| len = app->length - app->offset; |
| |
| gst_buffer_append_memory (buffer, |
| gst_memory_new_wrapped (GST_MEMORY_FLAG_READONLY, |
| app->data, app->length, app->offset, len, NULL, NULL)); |
| |
| GST_DEBUG ("feed buffer %p, offset %" G_GUINT64_FORMAT "-%u", buffer, |
| app->offset, len); |
| g_signal_emit_by_name (app->appsrc, "push-buffer", buffer, &ret); |
| gst_buffer_unref (buffer); |
| |
| app->offset += len; |
| |
| return; |
| } |
| |
| /* called when appsrc wants us to return data from a new position with the next |
| * call to push-buffer. */ |
| static gboolean |
| seek_data (GstElement * appsrc, guint64 position, App * app) |
| { |
| GST_DEBUG ("seek to offset %" G_GUINT64_FORMAT, position); |
| app->offset = position; |
| |
| return TRUE; |
| } |
| |
| /* this callback is called when playbin has constructed a source object to read |
| * from. Since we provided the appsrc:// uri to playbin, this will be the |
| * appsrc that we must handle. We set up some signals to push data into appsrc |
| * and one to perform a seek. */ |
| static void |
| found_source (GObject * object, GObject * orig, GParamSpec * pspec, App * app) |
| { |
| /* get a handle to the appsrc */ |
| g_object_get (orig, pspec->name, &app->appsrc, NULL); |
| |
| GST_DEBUG ("got appsrc %p", app->appsrc); |
| |
| /* we can set the length in appsrc. This allows some elements to estimate the |
| * total duration of the stream. It's a good idea to set the property when you |
| * can but it's not required. */ |
| g_object_set (app->appsrc, "size", (gint64) app->length, NULL); |
| /* we are seekable in push mode, this means that the element usually pushes |
| * out buffers of an undefined size and that seeks happen only occasionally |
| * and only by request of the user. */ |
| gst_util_set_object_arg (G_OBJECT (app->appsrc), "stream-type", "seekable"); |
| |
| /* configure the appsrc, we will push a buffer to appsrc when it needs more |
| * data */ |
| g_signal_connect (app->appsrc, "need-data", G_CALLBACK (feed_data), app); |
| g_signal_connect (app->appsrc, "seek-data", G_CALLBACK (seek_data), app); |
| } |
| |
| static gboolean |
| bus_message (GstBus * bus, GstMessage * message, App * app) |
| { |
| GST_DEBUG ("got message %s", |
| gst_message_type_get_name (GST_MESSAGE_TYPE (message))); |
| |
| switch (GST_MESSAGE_TYPE (message)) { |
| case GST_MESSAGE_ERROR: |
| g_error ("received error"); |
| g_main_loop_quit (app->loop); |
| break; |
| case GST_MESSAGE_EOS: |
| g_main_loop_quit (app->loop); |
| break; |
| default: |
| break; |
| } |
| return TRUE; |
| } |
| |
| int |
| main (int argc, char *argv[]) |
| { |
| App *app = &s_app; |
| GError *error = NULL; |
| GstBus *bus; |
| |
| gst_init (&argc, &argv); |
| |
| GST_DEBUG_CATEGORY_INIT (appsrc_playbin_debug, "appsrc-playbin", 0, |
| "appsrc playbin example"); |
| |
| if (argc < 2) { |
| g_print ("usage: %s <filename>\n", argv[0]); |
| return -1; |
| } |
| |
| /* try to open the file as an mmapped file */ |
| app->file = g_mapped_file_new (argv[1], FALSE, &error); |
| if (error) { |
| g_print ("failed to open file: %s\n", error->message); |
| g_error_free (error); |
| return -2; |
| } |
| /* get some vitals, this will be used to read data from the mmapped file and |
| * feed it to appsrc. */ |
| app->length = g_mapped_file_get_length (app->file); |
| app->data = (guint8 *) g_mapped_file_get_contents (app->file); |
| app->offset = 0; |
| |
| /* create a mainloop to get messages */ |
| app->loop = g_main_loop_new (NULL, TRUE); |
| |
| app->playbin = gst_element_factory_make ("playbin", NULL); |
| g_assert (app->playbin); |
| |
| bus = gst_pipeline_get_bus (GST_PIPELINE (app->playbin)); |
| |
| /* add watch for messages */ |
| gst_bus_add_watch (bus, (GstBusFunc) bus_message, app); |
| |
| /* set to read from appsrc */ |
| g_object_set (app->playbin, "uri", "appsrc://", NULL); |
| |
| /* get notification when the source is created so that we get a handle to it |
| * and can configure it */ |
| g_signal_connect (app->playbin, "deep-notify::source", |
| (GCallback) found_source, app); |
| |
| /* go to playing and wait in a mainloop. */ |
| gst_element_set_state (app->playbin, GST_STATE_PLAYING); |
| |
| /* this mainloop is stopped when we receive an error or EOS */ |
| g_main_loop_run (app->loop); |
| |
| GST_DEBUG ("stopping"); |
| |
| gst_element_set_state (app->playbin, GST_STATE_NULL); |
| |
| /* free the file */ |
| g_mapped_file_unref (app->file); |
| |
| gst_object_unref (bus); |
| g_main_loop_unref (app->loop); |
| |
| return 0; |
| } |