1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * This file incorporates work covered by the following license notice:
 *
 *   Licensed to the Apache Software Foundation (ASF) under one or more
 *   contributor license agreements. See the NOTICE file distributed
 *   with this work for additional information regarding copyright
 *   ownership. The ASF licenses this file to you under the Apache
 *   License, Version 2.0 (the "License"); you may not use this file
 *   except in compliance with the License. You may obtain a copy of
 *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
 */

#include "gstframegrabber.hxx"
#include "gstplayer.hxx"

#include <cppuhelper/supportsservice.hxx>

#include <gst/gstbuffer.h>
#include <gst/video/video.h>
#include <gst/video/gstvideosink.h>
#include <o3tl/safeint.hxx>
#include <vcl/graph.hxx>
#include <vcl/BitmapTools.hxx>

#include <string>

#define AVMEDIA_GST_FRAMEGRABBER_IMPLEMENTATIONNAME "com.sun.star.comp.avmedia.FrameGrabber_GStreamer"
#define AVMEDIA_GST_FRAMEGRABBER_SERVICENAME "com.sun.star.media.FrameGrabber_GStreamer"

using namespace ::com::sun::star;

namespace avmedia::gstreamer {

void FrameGrabber::disposePipeline()
{
    if( mpPipeline != nullptr )
    {
        gst_element_set_state( mpPipeline, GST_STATE_NULL );
        g_object_unref( G_OBJECT( mpPipeline ) );
        mpPipeline = nullptr;
    }
}

FrameGrabber::FrameGrabber( const OUString &rURL ) :
    FrameGrabber_BASE()
{
    gchar *pPipelineStr;
    pPipelineStr = g_strdup_printf(
        "uridecodebin uri=%s ! videoconvert ! videoscale ! appsink "
        "name=sink caps=\"video/x-raw,format=RGB,pixel-aspect-ratio=1/1\"",
        OUStringToOString( rURL, RTL_TEXTENCODING_UTF8 ).getStr() );

    GError *pError = nullptr;
    mpPipeline = gst_parse_launch( pPipelineStr, &pError );
    if( pError != nullptr) {
        g_warning( "Failed to construct frame-grabber pipeline '%s'\n", pError->message );
        g_error_free( pError );
        disposePipeline();
    }

    if( mpPipeline ) {
        // pre-roll
        switch( gst_element_set_state( mpPipeline, GST_STATE_PAUSED ) ) {
        case GST_STATE_CHANGE_FAILURE:
        case GST_STATE_CHANGE_NO_PREROLL:
            g_warning( "failure pre-rolling media" );
            disposePipeline();
            break;
        default:
            break;
        }
    }
    if( mpPipeline &&
        gst_element_get_state( mpPipeline, nullptr, nullptr, 5 * GST_SECOND ) == GST_STATE_CHANGE_FAILURE )
        disposePipeline();
}

FrameGrabber::~FrameGrabber()
{
    disposePipeline();
}

FrameGrabber* FrameGrabber::create( const OUString &rURL )
{
    return new FrameGrabber( rURL );
}

uno::Reference< graphic::XGraphic > SAL_CALL FrameGrabber::grabFrame( double fMediaTime )
{
    uno::Reference< graphic::XGraphic > xRet;

    if( !mpPipeline )
        return xRet;

    gint64 gst_position = llround( fMediaTime * GST_SECOND );
    gst_element_seek_simple(
        mpPipeline, GST_FORMAT_TIME,
        GstSeekFlags(GST_SEEK_FLAG_KEY_UNIT | GST_SEEK_FLAG_FLUSH),
        gst_position );

    GstElement *pSink = gst_bin_get_by_name( GST_BIN( mpPipeline ), "sink" );
    if( !pSink )
        return xRet;

    GstBuffer *pBuf = nullptr;<--- Assignment 'pBuf=nullptr', assigned value is 0
    GstCaps *pCaps = nullptr;<--- Assignment 'pCaps=nullptr', assigned value is 0

    // synchronously fetch the frame
    GstSample *pSample = nullptr;
    g_signal_emit_by_name( pSink, "pull-preroll", &pSample, nullptr );

    if( pSample )
    {
        pBuf = gst_sample_get_buffer( pSample );
        pCaps = gst_sample_get_caps( pSample );
    }

    // get geometry
    int nWidth = 0, nHeight = 0;
    if( !pCaps )<--- Condition '!pCaps' is always true
        g_warning( "could not get snapshot format\n" );
    else
    {
        GstStructure *pStruct = gst_caps_get_structure( pCaps, 0 );

        /* we need to get the final caps on the buffer to get the size */
        if( !gst_structure_get_int( pStruct, "width", &nWidth ) ||
            !gst_structure_get_int( pStruct, "height", &nHeight ) )
            nWidth = nHeight = 0;
    }

    if( pBuf && nWidth > 0 && nHeight > 0 &&<--- Condition 'pBuf' is always false
        // sanity check the size
        gst_buffer_get_size( pBuf ) >= o3tl::make_unsigned( nWidth * nHeight * 3 )
        )
    {
        sal_uInt8 *pData = nullptr;
        GstMapInfo aMapInfo;
        gst_buffer_map( pBuf, &aMapInfo, GST_MAP_READ );
        pData = aMapInfo.data;

        int nStride = GST_ROUND_UP_4( nWidth * 3 );
        BitmapEx aBmp = vcl::bitmap::CreateFromData(pData, nWidth, nHeight, nStride, 24 );

        gst_buffer_unmap( pBuf, &aMapInfo );
        xRet = Graphic( aBmp ).GetXGraphic();
    }

    return xRet;
}

OUString SAL_CALL FrameGrabber::getImplementationName(  )
{
    return AVMEDIA_GST_FRAMEGRABBER_IMPLEMENTATIONNAME;
}

sal_Bool SAL_CALL FrameGrabber::supportsService( const OUString& ServiceName )
{
    return cppu::supportsService(this, ServiceName);
}

uno::Sequence< OUString > SAL_CALL FrameGrabber::getSupportedServiceNames()
{
    return { AVMEDIA_GST_FRAMEGRABBER_SERVICENAME };
}

} // namespace

/* vim:set shiftwidth=4 softtabstop=4 expandtab: */