• Android 解决CameraView叠加2个以上滤镜拍照黑屏的BUG (二)


    1. 前言

    这段时间,在使用 natario1/CameraView 来实现带滤镜的预览拍照录像功能。
    由于CameraView封装的比较到位,在项目前期,的确为我们节省了不少时间。
    但随着项目持续深入,对于CameraView的使用进入深水区,逐渐出现满足不了我们需求的情况。
    特别是对于使用MultiFilter,叠加2个滤镜拍照是正常的,叠加2个以上滤镜拍照,预览时正常,拍出的照片就会全黑。
    Github中的issues中,也有不少提这个BUG的,但是作者一直没有修复该问题。

    在这里插入图片描述

    上篇文章,我们已经对带滤镜拍照的整个流程有了大概的了解,这篇文章,我们重点来看takeFrame方法,这是带滤镜拍照的核心代码。

    接下来我们就来解析takeFrame的源码

    2. 创建EGL窗口

    首先,会创建EGL窗口,这里创建了一个假的,前台不可见的一个EGL窗口,专门用来保存图片

    // 0. EGL window will need an output.
    // We create a fake one as explained in javadocs.
    final int fakeOutputTextureId = 9999;
    SurfaceTexture fakeOutputSurface = new SurfaceTexture(fakeOutputTextureId);
    fakeOutputSurface.setDefaultBufferSize(mResult.size.getWidth(), mResult.size.getHeight());
    
    • 1
    • 2
    • 3
    • 4
    • 5

    3. 创建EGL Surface

    接着,来创建EglSurface

    // 1. Create an EGL surface
    final EglCore core = new EglCore(eglContext, EglCore.FLAG_RECORDABLE);
    final EglSurface eglSurface = new EglWindowSurface(core, fakeOutputSurface);
    eglSurface.makeCurrent();
    
    • 1
    • 2
    • 3
    • 4

    3.1 EglSurface

    其中,这个com.otaliastudios.opengl.EglSurface是作者自己创建的,继承自EglNativeSurface

    public open class EglNativeSurface internal constructor(
            internal var eglCore: EglCore,
            internal var eglSurface: EglSurface) {
    
        private var width = -1
        private var height = -1
    
        /**
         * Can be called by subclasses whose width is guaranteed to never change,
         * so we can cache this value. For window surfaces, this should not be called.
         */
        @Suppress("unused")
        protected fun setWidth(width: Int) {
            this.width = width
        }
    
        /**
         * Can be called by subclasses whose height is guaranteed to never change,
         * so we can cache this value. For window surfaces, this should not be called.
         */
        @Suppress("unused")
        protected fun setHeight(height: Int) {
            this.height = height
        }
    
        /**
         * Returns the surface's width, in pixels.
         *
         * If this is called on a window surface, and the underlying surface is in the process
         * of changing size, we may not see the new size right away (e.g. in the "surfaceChanged"
         * callback).  The size should match after the next buffer swap.
         */
        @Suppress("MemberVisibilityCanBePrivate")
        public fun getWidth(): Int {
            return if (width < 0) {
                eglCore.querySurface(eglSurface, EGL_WIDTH)
            } else {
                width
            }
        }
    
        /**
         * Returns the surface's height, in pixels.
         */
        @Suppress("MemberVisibilityCanBePrivate")
        public fun getHeight(): Int {
            return if (height < 0) {
                eglCore.querySurface(eglSurface, EGL_HEIGHT)
            } else {
                height
            }
        }
    
        /**
         * Release the EGL surface.
         */
        public open fun release() {
            eglCore.releaseSurface(eglSurface)
            eglSurface = EGL_NO_SURFACE
            height = -1
            width = -1
        }
    
        /**
         * Whether this surface is current on the
         * attached [EglCore].
         */
        @Suppress("MemberVisibilityCanBePrivate")
        public fun isCurrent(): Boolean {
            return eglCore.isSurfaceCurrent(eglSurface)
        }
    
        /**
         * Makes our EGL context and surface current.
         */
        @Suppress("unused")
        public fun makeCurrent() {
            eglCore.makeSurfaceCurrent(eglSurface)
        }
    
        /**
         * Makes no surface current for the attached [eglCore].
         */
        @Suppress("unused")
        public fun makeNothingCurrent() {
            eglCore.makeCurrent()
        }
    
        /**
         * Sends the presentation time stamp to EGL.
         * [nsecs] is the timestamp in nanoseconds.
         */
        @Suppress("unused")
        public fun setPresentationTime(nsecs: Long) {
            eglCore.setSurfacePresentationTime(eglSurface, nsecs)
        }
    }
    
    • 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

    3.2 EglCore

    可以看到EglNativeSurface内部其实基本上就是调用的EglCoreEglCore内部封装了EGL相关的方法。
    这里的具体实现我们不需要细看,只需要知道EglSurface是作者自己实现的一个Surface就可以了,内部封装了EGL,可以实现和GlSurfaceView类似的一些功能,在这里使用的EglSurface是专门给拍照准备的。

    这样做的好处在于拍照的时候,预览界面(GLSurfaceView)不会出现卡顿的现象,但是坏处也显而易见,就是可能会出现预览效果和拍照的实际效果不一致的情况。(也就是本文所遇到的BUG的情况)

    OpenGL是一个跨平台的操作GPUAPIOpenGL需要本地视窗系统进行交互,就需要一个中间控制层。
    EGL就是连接OpenGL ES和本地窗口系统的接口,引入EGL就是为了屏蔽不同平台上的区别。

    public expect class EglCore : EglNativeCore
    
    public open class EglNativeCore internal constructor(sharedContext: EglContext = EGL_NO_CONTEXT, flags: Int = 0) {
    
        private var eglDisplay: EglDisplay = EGL_NO_DISPLAY
        private var eglContext: EglContext = EGL_NO_CONTEXT
        private var eglConfig: EglConfig? = null
        private var glVersion = -1 // 2 or 3
    
        init {
            eglDisplay = eglGetDefaultDisplay()
            if (eglDisplay === EGL_NO_DISPLAY) {
                throw RuntimeException("unable to get EGL14 display")
            }
    
            if (!eglInitialize(eglDisplay, IntArray(1), IntArray(1))) {
                throw RuntimeException("unable to initialize EGL14")
            }
    
            // Try to get a GLES3 context, if requested.
            val chooser = EglNativeConfigChooser()
            val recordable = flags and FLAG_RECORDABLE != 0
            val tryGles3 = flags and FLAG_TRY_GLES3 != 0
            if (tryGles3) {
                val config = chooser.getConfig(eglDisplay, 3, recordable)
                if (config != null) {
                    val attributes = intArrayOf(EGL_CONTEXT_CLIENT_VERSION, 3, EGL_NONE)
                    val context = eglCreateContext(eglDisplay, config, sharedContext, attributes)
                    try {
                        Egloo.checkEglError("eglCreateContext (3)")
                        eglConfig = config
                        eglContext = context
                        glVersion = 3
                    } catch (e: Exception) {
                        // Swallow, will try GLES2
                    }
                }
            }
    
            // If GLES3 failed, go with GLES2.
            val tryGles2 = eglContext === EGL_NO_CONTEXT
            if (tryGles2) {
                val config = chooser.getConfig(eglDisplay, 2, recordable)
                if (config != null) {
                    val attributes = intArrayOf(EGL_CONTEXT_CLIENT_VERSION, 2, EGL_NONE)
                    val context = eglCreateContext(eglDisplay, config, sharedContext, attributes)
                    Egloo.checkEglError("eglCreateContext (2)")
                    eglConfig = config
                    eglContext = context
                    glVersion = 2
                } else {
                    throw RuntimeException("Unable to find a suitable EGLConfig")
                }
            }
        }
    
        /**
         * Discards all resources held by this class, notably the EGL context.  This must be
         * called from the thread where the context was created.
         * On completion, no context will be current.
         */
        internal open fun release() {
            if (eglDisplay !== EGL_NO_DISPLAY) {
                // Android is unusual in that it uses a reference-counted EGLDisplay.  So for
                // every eglInitialize() we need an eglTerminate().
                eglMakeCurrent(eglDisplay, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT)
                eglDestroyContext(eglDisplay, eglContext)
                eglReleaseThread()
                eglTerminate(eglDisplay)
            }
            eglDisplay = EGL_NO_DISPLAY
            eglContext = EGL_NO_CONTEXT
            eglConfig = null
        }
    
        /**
         * Makes this context current, with no read / write surfaces.
         */
        internal open fun makeCurrent() {
            if (!eglMakeCurrent(eglDisplay, EGL_NO_SURFACE, EGL_NO_SURFACE, eglContext)) {
                throw RuntimeException("eglMakeCurrent failed")
            }
        }
    
        /**
         * Destroys the specified surface.  Note the EGLSurface won't actually be destroyed if it's
         * still current in a context.
         */
        internal fun releaseSurface(eglSurface: EglSurface) {
            eglDestroySurface(eglDisplay, eglSurface)
        }
    
        /**
         * Creates an EGL surface associated with a Surface.
         * If this is destined for MediaCodec, the EGLConfig should have the "recordable" attribute.
         */
        internal fun createWindowSurface(surface: Any): EglSurface {
            // Create a window surface, and attach it to the Surface we received.
            val surfaceAttribs = intArrayOf(EGL_NONE)
            val eglSurface = eglCreateWindowSurface(eglDisplay, eglConfig!!, surface, surfaceAttribs)
            Egloo.checkEglError("eglCreateWindowSurface")
            if (eglSurface === EGL_NO_SURFACE) throw RuntimeException("surface was null")
            return eglSurface
        }
    
        /**
         * Creates an EGL surface associated with an offscreen buffer.
         */
        internal fun createOffscreenSurface(width: Int, height: Int): EglSurface {
            val surfaceAttribs = intArrayOf(EGL_WIDTH, width, EGL_HEIGHT, height, EGL_NONE)
            val eglSurface = eglCreatePbufferSurface(eglDisplay, eglConfig!!, surfaceAttribs)
            Egloo.checkEglError("eglCreatePbufferSurface")
            if (eglSurface === EGL_NO_SURFACE) throw RuntimeException("surface was null")
            return eglSurface
        }
    
        /**
         * Makes our EGL context current, using the supplied surface for both "draw" and "read".
         */
        internal fun makeSurfaceCurrent(eglSurface: EglSurface) {
            if (eglDisplay === EGL_NO_DISPLAY) logv("EglCore", "NOTE: makeSurfaceCurrent w/o display")
            if (!eglMakeCurrent(eglDisplay, eglSurface, eglSurface, eglContext)) {
                throw RuntimeException("eglMakeCurrent failed")
            }
        }
    
        /**
         * Makes our EGL context current, using the supplied "draw" and "read" surfaces.
         */
        internal fun makeSurfaceCurrent(drawSurface: EglSurface, readSurface: EglSurface) {
            if (eglDisplay === EGL_NO_DISPLAY) logv("EglCore", "NOTE: makeSurfaceCurrent w/o display")
            if (!eglMakeCurrent(eglDisplay, drawSurface, readSurface, eglContext)) {
                throw RuntimeException("eglMakeCurrent(draw,read) failed")
            }
        }
    
        /**
         * Calls eglSwapBuffers. Use this to "publish" the current frame.
         * @return false on failure
         */
        internal fun swapSurfaceBuffers(eglSurface: EglSurface): Boolean {
            return eglSwapBuffers(eglDisplay, eglSurface)
        }
    
        /**
         * Sends the presentation time stamp to EGL.  Time is expressed in nanoseconds.
         */
        internal fun setSurfacePresentationTime(eglSurface: EglSurface, nsecs: Long) {
            eglPresentationTime(eglDisplay, eglSurface, nsecs)
        }
    
        /**
         * Returns true if our context and the specified surface are current.
         */
        internal fun isSurfaceCurrent(eglSurface: EglSurface): Boolean {
            return eglContext == eglGetCurrentContext()
                    && eglSurface == eglGetCurrentSurface(EGL_DRAW)
        }
    
        /**
         * Performs a simple surface query.
         */
        internal fun querySurface(eglSurface: EglSurface, what: Int): Int {
            val value = IntArray(1)
            eglQuerySurface(eglDisplay, eglSurface, what, value)
            return value[0]
        }
    
        public companion object {
            /**
             * Constructor flag: surface must be recordable.  This discourages EGL from using a
             * pixel format that cannot be converted efficiently to something usable by the video
             * encoder.
             */
            internal const val FLAG_RECORDABLE = 0x01
    
            /**
             * Constructor flag: ask for GLES3, fall back to GLES2 if not available.  Without this
             * flag, GLES2 is used.
             */
            internal const val FLAG_TRY_GLES3 = 0x02
        }
    }
    
    • 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
    • 177
    • 178
    • 179
    • 180
    • 181
    • 182
    • 183

    4. 修改transform

    这里的mTextureDrawerGlTextureDrawerGlTextureDrawer是一个绘制的管理类,无论是GlCameraPreview(预览)还是SnapshotGlPictureRecorder(带滤镜拍照),都是调用GlTextureDrawer.draw()来渲染openGL的。

    public class GlTextureDrawer {
    	//...省略了不重要的代码...
    
        private final GlTexture mTexture;
        private float[] mTextureTransform = Egloo.IDENTITY_MATRIX.clone();
    
        public void draw(final long timestampUs) {
            //...省略了不重要的代码...
            
            if (mProgramHandle == -1) {
                mProgramHandle = GlProgram.create(
                        mFilter.getVertexShader(),
                        mFilter.getFragmentShader());
                mFilter.onCreate(mProgramHandle);
            }
    
            GLES20.glUseProgram(mProgramHandle);
            mTexture.bind();
            mFilter.draw(timestampUs, mTextureTransform);
            mTexture.unbind();
            GLES20.glUseProgram(0);
        }
    
        public void release() {
            if (mProgramHandle == -1) return;
            mFilter.onDestroy();
            GLES20.glDeleteProgram(mProgramHandle);
            mProgramHandle = -1;
        }
    }
    
    • 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

    transform ,也就是mTextureTransform,会传到Filter.draw()中,最终会改变OpenGL绘制的坐标矩阵,也就是GLSL中的uMVPMatrix变量。
    而这边就是修改transform 的值,从而对图像进行镜像、旋转等操作。

    final float[] transform = mTextureDrawer.getTextureTransform();
    
    // 2. Apply preview transformations
    surfaceTexture.getTransformMatrix(transform);
    float scaleTranslX = (1F - scaleX) / 2F;
    float scaleTranslY = (1F - scaleY) / 2F;
    Matrix.translateM(transform, 0, scaleTranslX, scaleTranslY, 0);
    Matrix.scaleM(transform, 0, scaleX, scaleY, 1);
    
    // 3. Apply rotation and flip
     // If this doesn't work, rotate "rotation" before scaling, like GlCameraPreview does.
     Matrix.translateM(transform, 0, 0.5F, 0.5F, 0); // Go back to 0,0
     Matrix.rotateM(transform, 0, rotation + mResult.rotation, 0, 0, 1); // Rotate to OUTPUT
     Matrix.scaleM(transform, 0, 1, -1, 1); // Vertical flip because we'll use glReadPixels
     Matrix.translateM(transform, 0, -0.5F, -0.5F, 0); // Go back to old position
    
    • 1
    • 2
    • 3
    • 4
    • 5
    • 6
    • 7
    • 8
    • 9
    • 10
    • 11
    • 12
    • 13
    • 14
    • 15

    5. 绘制Overlay

    这个没有研究过,似乎是用来绘制覆盖层。这不重要,这里跳过,一般也不会进入这个逻辑。

    // 4. Do pretty much the same for overlays
    if (mHasOverlay) {
        // 1. First we must draw on the texture and get latest image
        mOverlayDrawer.draw(Overlay.Target.PICTURE_SNAPSHOT);
    
        // 2. Then we can apply the transformations
        Matrix.translateM(mOverlayDrawer.getTransform(), 0, 0.5F, 0.5F, 0);
        Matrix.rotateM(mOverlayDrawer.getTransform(), 0, mResult.rotation, 0, 0, 1);
        Matrix.scaleM(mOverlayDrawer.getTransform(), 0, 1, -1, 1); // Vertical flip because we'll use glReadPixels
        Matrix.translateM(mOverlayDrawer.getTransform(), 0, -0.5F, -0.5F, 0);
    }
    mResult.rotation = 0;
    
    • 1
    • 2
    • 3
    • 4
    • 5
    • 6
    • 7
    • 8
    • 9
    • 10
    • 11
    • 12

    6. 绘制并保存

    这里就是带滤镜拍照部分,核心中的核心代码了。
    这里主要分为两步

    • mTextureDrawer.draw : 绘制滤镜
    • eglSurface.toByteArray : 将画面保存为JPEG格式的Byte数组
    // 5. Draw and save
    long timestampUs = surfaceTexture.getTimestamp() / 1000L;
    LOG.i("takeFrame:", "timestampUs:", timestampUs);
    mTextureDrawer.draw(timestampUs);
    if (mHasOverlay) mOverlayDrawer.render(timestampUs);
    mResult.data = eglSurface.toByteArray(Bitmap.CompressFormat.JPEG);
    
    • 1
    • 2
    • 3
    • 4
    • 5
    • 6

    这部分具体的代码具体详见下篇文章

    7. 释放资源

    // 6. Cleanup
    eglSurface.release();
    mTextureDrawer.release();
    fakeOutputSurface.release();
    if (mHasOverlay) mOverlayDrawer.release();
    core.release();
    dispatchResult();
    
    • 1
    • 2
    • 3
    • 4
    • 5
    • 6
    • 7

    8. 其他

    8.1 解决CameraView滤镜黑屏系列

    Android 解决CameraView叠加2个以上滤镜拍照黑屏的BUG (一)_氦客的博客-CSDN博客
    Android 解决CameraView叠加2个以上滤镜拍照黑屏的BUG (二)_氦客的博客-CSDN博客
    Android 解决CameraView叠加2个以上滤镜拍照黑屏的BUG (三)_氦客的博客-CSDN博客

    8.2 Android Camera2 系列

    更多Camera2相关文章,请看
    十分钟实现 Android Camera2 相机预览_氦客的博客-CSDN博客
    十分钟实现 Android Camera2 相机拍照_氦客的博客-CSDN博客
    十分钟实现 Android Camera2 视频录制_氦客的博客-CSDN博客

    8.3 Android 相机相关文章

    Android 使用CameraX实现预览/拍照/录制视频/图片分析/对焦/缩放/切换摄像头等操作_氦客的博客-CSDN博客
    Android 从零开发一个简易的相机App_android开发简易app_氦客的博客-CSDN博客
    Android 使用Camera1实现相机预览、拍照、录像_android 相机预览_氦客的博客-CSDN博客

  • 相关阅读:
    搭建hadoop集群
    【C++ STL】-- 二叉搜索树
    明峰医疗冲刺科创板:年营收3.5亿元 拟募资6.24亿
    【学习笔记】无线通信与安全
    unix安装ANT
    nodejs+vue大学食堂订餐系统
    【设计模式深度剖析】【6】【结构型】【外观模式】| 以电脑开关按钮为例,并结合微服务架构的API网关加深理解
    Halcon实现3维点云平面拟合
    [附源码]Python计算机毕业设计Django基于Java的日用品在线电商平台
    linux--进度条
  • 原文地址:https://blog.csdn.net/EthanCo/article/details/134310244