Argus Camera Sample
Argus Camera Sample
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Friends Macros Pages
StreamConsumer.h
Go to the documentation of this file.
1 /*
2  * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * * Redistributions of source code must retain the above copyright
8  * notice, this list of conditions and the following disclaimer.
9  * * Redistributions in binary form must reproduce the above copyright
10  * notice, this list of conditions and the following disclaimer in the
11  * documentation and/or other materials provided with the distribution.
12  * * Neither the name of NVIDIA CORPORATION nor the names of its
13  * contributors may be used to endorse or promote products derived
14  * from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY
17  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
20  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
21  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
23  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
24  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #ifndef STREAM_CONSUMER_H
30 #define STREAM_CONSUMER_H
31 
32 #include <EGL/egl.h>
33 #include <EGL/eglext.h>
34 
35 #include "Thread.h"
36 #include "GLContext.h"
37 
38 // Workaround for Bug 1736040, Jira CA-167
39 // Root cause is that the StreamConsumer updates the stream texture with eglStreamConsumerAcquire
40 // while the Composer is using the same texture to render. Although the EGL spec says that
41 // textures are 'latched', e.g. updated atomically occasionally the texture is undefined (content
42 // is zero, rendered as green in YUV color space) occasionally.
43 // The workaround uses a mutex to make sure that eglStreamConsumerAcquire is called only when the
44 // Composer is *not* using the texture. The StreamConsumer polls the EGL stream and takes the
45 // mutex if a new frame is available. It latches that frame and releases the mutex. The Composer
46 // holds the mutex while using the stream texture to render.
47 #define WAR_EGL_STREAM_RACE
48 
49 #ifdef WAR_EGL_STREAM_RACE
50 #include "Mutex.h"
51 #endif // WAR_EGL_STREAM_RACE
52 
53 namespace ArgusSamples
54 {
55 
56 /**
57  * This class handles creation of a thread acquiring from an EGL stream
58  */
59 class StreamConsumer : public Thread
60 {
61 public:
62  explicit StreamConsumer(EGLStreamKHR eglStream);
64 
65  bool initialize();
66  bool shutdown();
67 
68  bool isEGLStream(EGLStreamKHR eglStream) const;
69  uint32_t getStreamTextureID() const;
70 
71  bool setStreamAspectRatio(float aspectRatio);
72  float getStreamAspectRatio() const;
73 
74 #ifdef WAR_EGL_STREAM_RACE
76 #endif // WAR_EGL_STREAM_RACE
77 
78 private:
79  GLContext m_context;
80  EGLStreamKHR m_eglStream;
81  EGLint m_streamState;
82  uint32_t m_streamTexture;
83  float m_aspectRatio; ///< aspect ration of the images transported by the stream
84 #ifdef WAR_EGL_STREAM_RACE
85  EGLSyncKHR m_sync; ///< stream sync object
86  Mutex m_mutex; ///< to protect access of the stream texture
87 #endif // WAR_EGL_STREAM_RACE
88 
89  /**
90  * Hide default constructor
91  */
93 
94  virtual bool threadInitialize();
95  virtual bool threadExecute();
96  virtual bool threadShutdown();
97 };
98 
99 }; // namespace ArgusSamples
100 
101 #endif // STREAM_CONSUMER_H