UxPlay/renderers/video_renderer_gstreamer.c

/**
 * RPiPlay - An open-source AirPlay mirroring server for Raspberry Pi
 * Copyright (C) 2019 Florian Draschbacher
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
 */

#include "video_renderer.h"
#include <assert.h>
#include <gst/gst.h>
#include <gst/app/gstappsrc.h>

#ifdef X_DISPLAY_FIX
#include "x_display_fix.h"
#endif

struct video_renderer_s {
    logger_t *logger;
    GstElement *appsrc, *pipeline, *sink;
    GstBus *bus;
};

static gboolean check_plugins (void)
{
    int i;
    gboolean ret;
    GstRegistry *registry;
    const gchar *needed[] = { "app", "libav", "playback", "autodetect", NULL};

    registry = gst_registry_get ();
    ret = TRUE;
    for (i = 0; i < g_strv_length ((gchar **) needed); i++) {
        GstPlugin *plugin;
        plugin = gst_registry_find_plugin (registry, needed[i]);
        if (!plugin) {
            g_print ("Required gstreamer plugin '%s' not found\n", needed[i]);
            ret = FALSE;
            continue;
        }
        gst_object_unref (plugin);
    }
    return ret;
}

static void append_videoflip (GString *launch, const videoflip_t *flip, const videoflip_t *rot) {
    /* videoflip image transform */
    switch (*flip) {
    case INVERT:
        switch (*rot)  {
        case LEFT:
	    g_string_append(launch, "videoflip method=clockwise ! ");
	    break;
        case RIGHT:
            g_string_append(launch, "videoflip method=counterclockwise ! ");
            break;
        default:
	    g_string_append(launch, "videoflip method=rotate-180 ! ");
	    break;
        }
        break;
    case HFLIP:
        switch (*rot) {
        case LEFT:
            g_string_append(launch, "videoflip method=upper-left-diagonal ! ");
            break;
        case RIGHT: 
            g_string_append(launch, "videoflip method=upper-right-diagonal ! ");
            break;
        default:
            g_string_append(launch, "videoflip method=horizontal-flip ! ");
            break;
        }
        break;
    case VFLIP:
        switch (*rot) {
        case LEFT:
            g_string_append(launch, "videoflip method=upper-right-diagonal ! ");
            break;
        case RIGHT: 
            g_string_append(launch, "videoflip method=upper-left-diagonal ! ");
            break;
        default:
            g_string_append(launch, "videoflip method=vertical-flip ! ");
	  break;
	}
        break;
    default:
        switch (*rot) {
        case LEFT:
            g_string_append(launch, "videoflip method=counterclockwise ! ");
            break;
        case RIGHT: 
            g_string_append(launch, "videoflip method=clockwise ! ");
            break;
        default:
            break;
        }
        break;
    }
}	

video_renderer_t *video_renderer_init(logger_t *logger, const char *server_name, videoflip_t videoflip[2], const char *videosink) {
    video_renderer_t *renderer;
    GError *error = NULL;

#ifdef X_DISPLAY_FIX
    get_x_display_root();
#endif

    /* this call to g_set_application_name makes server_name appear in the display window title bar, */
    /* (instead of the program name uxplay taken from (argv[0]). It is only set one time. */

    if (!g_get_application_name()) g_set_application_name(server_name);

    renderer = calloc(1, sizeof(video_renderer_t));
    assert(renderer);

    gst_init(NULL, NULL);

    renderer->logger = logger;
 
    assert(check_plugins ());

    GString *launch = g_string_new("-e appsrc name=video_source stream-type=0 format=GST_FORMAT_TIME is-live=true !"
                     "queue ! decodebin ! videoconvert ! ");
    append_videoflip(launch, &videoflip[0], &videoflip[1]);
    /* replace "autovideosink" with "fpsdisplaysink" (from gstreamer-plugins-bad) to display framerate */
    if (videosink) {
        g_string_append(launch, videosink);
    } else {
        g_string_append(launch, "autovideosink");
    }
    g_string_append(launch, " name=video_sink sync=false");
    renderer->pipeline = gst_parse_launch(launch->str,  &error);
    g_assert (renderer->pipeline);

    renderer->appsrc = gst_bin_get_by_name (GST_BIN (renderer->pipeline), "video_source");
    renderer->sink = gst_bin_get_by_name (GST_BIN (renderer->pipeline), "video_sink");

    return renderer;
}

void video_renderer_start(video_renderer_t *renderer) {
    //g_signal_connect( renderer->pipeline, "deep-notify", G_CALLBACK(gst_object_default_deep_notify ), NULL );
    gst_element_set_state (renderer->pipeline, GST_STATE_PLAYING);
    renderer->bus = gst_element_get_bus(renderer->pipeline);
}

void video_renderer_render_buffer(video_renderer_t *renderer, raop_ntp_t *ntp, unsigned char* data, int data_len, uint64_t pts, int type) {
    GstBuffer *buffer;

    assert(data_len != 0);

    buffer = gst_buffer_new_and_alloc(data_len);
    assert(buffer != NULL);
    GST_BUFFER_DTS(buffer) = (GstClockTime)pts;
    gst_buffer_fill(buffer, 0, data, data_len);
    gst_app_src_push_buffer (GST_APP_SRC(renderer->appsrc), buffer);

#ifdef X_DISPLAY_FIX
    fix_x_window_name();
#endif
}

void video_renderer_flush(video_renderer_t *renderer) {

}

bool video_renderer_listen(video_renderer_t *renderer) {
    GstMessage *msg = NULL;

    /* listen  on the gstreamer pipeline bus for an error or EOS.   */
    /* return true if this occurs, and false if 100 millisecs have */
    /* elapsed with no such event occuring.                         */
    
    msg = gst_bus_timed_pop_filtered(renderer->bus, 100 * GST_MSECOND,
                                  GST_MESSAGE_ERROR | GST_MESSAGE_EOS);
    /* parse message */
    if (msg != NULL)  {
        GError *err;
        gchar *debug_info;

        switch (GST_MESSAGE_TYPE (msg)) {
	case GST_MESSAGE_ERROR:
            gst_message_parse_error (msg, &err, &debug_info);
            g_printerr("GStreamer: %s\n", err->message);
            g_clear_error (&err);
            g_free (debug_info);
            break;
        case GST_MESSAGE_EOS:
            g_print("End-Of-Stream reached.\n");
            break;
        default:
            g_printerr("unexpected message\n");
            break;
        }
        gst_message_unref(msg);
        return true;
    }
    return false;
}

void video_renderer_destroy(video_renderer_t *renderer) {
    gst_app_src_end_of_stream (GST_APP_SRC(renderer->appsrc));
    gst_object_unref(renderer->bus);
    gst_element_set_state (renderer->pipeline, GST_STATE_NULL);
    gst_object_unref (renderer->pipeline);
    if (renderer) {
        free(renderer);
    }
}

/* not implemented for gstreamer */
void video_renderer_update_background(video_renderer_t *renderer, int type) {
}