Linux/AM5728: GStreamer application development

Prerak Patel

Part Number: AM5728

Tool/software: Linux

Hi,

My pipeline is

gst-launch-1.0 -e v4l2src device=/dev/video1 ! 'video/x-raw, format=(string)YUY2, width=(int)640, height=(int)720, framerate=10/1' ! ducatijpegdec ! tee name=t ! queue ! videocrop left = 2016 right=1008 ! videoscale ! video/x-raw , format=NV12 , height=240 , width=320 ! videoconvert ! video/x-raw , format=Y444 ! plugin1 ! fakesink t. ! queue min-threshold-buffers=2 ! ducatih264enc hrd-buffer-size=4064256 rate-preset=1 ! plugin2 ! fakesink

This pipeline works fine. I am going to make application based on this pipeline but it gives segmentation fault while adding elements.

Fullscreen GstApp.c Download

#include <stdio.h>
#include <gst/gst.h>


/* BUS function for ERROR */

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;
 }

/* Main function does atual processing */

int main (int argc , char *argv[])
{
    GstElement *pipeline, *video_source, *filter_source, *ducatijpegdec, *tee, *rtsp_queue, *ducatih264enc, *plugin2, *rtsp_sink;    
    GstElement *ovready_queue, *video_crop, *video_scale, *filter_scale, *video_convert, *filter_convert, *plugin1, *ovready_sink; 
    GstBus *bus;
    GstMessage *msg;
    GstPadTemplate *tee_src_pad_template;
    GstPad *tee_rtsp_pad, *tee_ovready_pad;
    GstPad *queue_rtsp_pad, *queue_ovready_pad;
    GstCaps *source_caps, *convert_caps, *scale_caps;

    gst_init (&argc, &argv);

    /* Create the elements */
    video_source = gst_element_factory_make ("v4l2src", "video_source");
    filter_source = gst_element_factory_make ("capsfilter", "filter_source");
    ducatijpegdec = gst_element_factory_make ("ducatijpegdec", "ducatijpegdec");
    
    tee = gst_element_factory_make ("tee", "tee");

    /* ovready thread */    
    ovready_queue = gst_element_factory_make ("queue", "ovready_queue"); 
    video_crop = gst_element_factory_make ("videocrop", "video_crop");
    video_scale = gst_element_factory_make ("videoscale", "video_scale");
    filter_scale = gst_element_factory_make ("capsfilter", "filter_scale");
    video_convert = gst_element_factory_make ("videoconvert", "video_convert");
    filter_convert= gst_element_factory_make ("capsfilter", "filter_convert");
    plugin1 = gst_element_factory_make ("plugin1", "plugin1");
    ovready_sink = gst_element_factory_make ("fakesink", "ovready_sink");

    /* rtsp thread */
    rtsp_queue = gst_element_factory_make ("queue", "rtsp_queue"); 
    ducatijpegdec = gst_element_factory_make ("ducatih264enc", "ducatih264enc");
    plugin2 = gst_element_factory_make ("plugin2", "plugin2");
    rtsp_sink = gst_element_factory_make ("fakesink", "rtsp_sink");



    /* source_caps*/
    source_caps = gst_caps_new_simple ("video/x-raw",
    "format", G_TYPE_STRING, "YUY2",
    "width", G_TYPE_INT, 640,
    "height", G_TYPE_INT, 720,
    "framerate", G_TYPE_FLOAT, 15/1,
     NULL);

    /* Set up elements for source_caps*/
    g_object_set (G_OBJECT (filter_source), "caps", source_caps, NULL);
    gst_caps_unref (source_caps);
    g_object_set (G_OBJECT (video_source), "device", "/dev/video1", NULL);


    /* scale_caps */
    scale_caps = gst_caps_new_simple ("video/x-raw",
    "format", G_TYPE_STRING, "NV12",
    "width", G_TYPE_INT, 320,
    "height", G_TYPE_INT, 240,
     NULL);

    /* Set up elements for scale_caps*/
    g_object_set (G_OBJECT (filter_scale), "caps", scale_caps, NULL);
    gst_caps_unref (scale_caps);
    

    /* convert_caps */
    convert_caps = gst_caps_new_simple ("video/x-raw",
    "format", G_TYPE_STRING, "Y444",
    "width", G_TYPE_INT, 320,
    "height", G_TYPE_INT, 240,
     NULL);

    /* Set up elements for convert_caps */
    g_object_set (G_OBJECT (filter_convert), "caps", convert_caps, NULL);
    gst_caps_unref (convert_caps);


    /* Set up elements for rtsp_queue */
    g_object_set (G_OBJECT (rtsp_queue), "min-threshold-buffers", 2, NULL);

    /* Set up elements for ducatih264enc */
    g_object_set (G_OBJECT (ducatih264enc), "rate-preset", 1, NULL);


    /* Set up elements for video_crop */
    g_object_set (G_OBJECT (video_crop), "left", 2016, NULL);

    
    /* Set up elements for video_crop */
    g_object_set (G_OBJECT (video_crop), "right", 1008, NULL);


    /* Create the empty pipeline */
    pipeline = gst_pipeline_new ("test-pipeline");

    if (!pipeline || !video_source || !filter_source || !ducatijpegdec || !tee || !ovready_queue || !video_crop || !video_scale || !filter_scale || !video_convert || !filter_convert || !plugin1 || !ovready_sink || !rtsp_queue || !ducatih264enc || !plugin2 || !rtsp_sink) 
    {
        g_printerr ("Not all elements could be created.\n");
        return -1;
    }

    /* Link all elements that can be automatically linked because they have "Always" pads */
     gst_bin_add_many (GST_BIN (pipeline), video_source, ducatijpegdec, tee, ovready_queue, video_crop, video_scale, video_convert, plugin1, ovready_sink, rtsp_queue, ducatih264enc, plugin2, rtsp_sink, NULL);
  
    if (gst_element_link_many (video_source, ducatijpegdec, tee, NULL) != TRUE ||gst_element_link_many (ovready_queue, video_crop, video_scale, video_convert, plugin1, ovready_sink, NULL) != TRUE || gst_element_link_many (rtsp_queue, ducatih264enc, plugin2, rtsp_sink, NULL) != TRUE) 
    {
        g_printerr ("Elements could not be linked.\n");
        gst_object_unref (pipeline);
        return -1;
    }


    /* Manually link the Tee, which has "Request" pads */
    tee_src_pad_template = gst_element_class_get_pad_template (GST_ELEMENT_GET_CLASS (tee), "src_%d");
    tee_ovready_pad = gst_element_request_pad (tee, tee_src_pad_template, NULL, NULL);
    g_print ("Obtained request pad %s for audio branch.\n", gst_pad_get_name (tee_ovready_pad));
    queue_ovready_pad = gst_element_get_static_pad (ovready_queue, "sink");
    tee_rtsp_pad = gst_element_request_pad (tee, tee_src_pad_template, NULL, NULL);
    g_print ("Obtained request pad %s for video branch.\n", gst_pad_get_name (tee_rtsp_pad));
    queue_rtsp_pad = gst_element_get_static_pad (rtsp_queue, "sink");
    if (gst_pad_link (tee_ovready_pad, queue_ovready_pad) != GST_PAD_LINK_OK || gst_pad_link (tee_rtsp_pad, queue_rtsp_pad) != GST_PAD_LINK_OK) 
    {
        g_printerr ("Tee could not be linked.\n");
        gst_object_unref (pipeline);
        return -1;
    }
    gst_object_unref (queue_ovready_pad);
    gst_object_unref (queue_rtsp_pad);


    /* Start playing the pipeline */
    gst_element_set_state (pipeline, GST_STATE_PLAYING);

    /* Wait until error or EOS */
    bus = gst_element_get_bus (pipeline);
    msg = gst_bus_timed_pop_filtered (bus, GST_CLOCK_TIME_NONE, GST_MESSAGE_ERROR | GST_MESSAGE_EOS);

    /* Release the request pads from the Tee, and unref them */
    gst_element_release_request_pad (tee, tee_ovready_pad);
    gst_element_release_request_pad (tee, tee_rtsp_pad);
    gst_object_unref (tee_ovready_pad);
    gst_object_unref (tee_rtsp_pad);

    /* Free resources */
    if (msg != NULL)
    {
        gst_message_unref (msg);
    }
    gst_object_unref (bus);
    gst_element_set_state (pipeline, GST_STATE_NULL);

    gst_object_unref (pipeline);
    return 0;
}

Attached my application. Give me some solution regarding issue.

Regards,

Prerak

over 8 years ago