我从LogCat收到这些错误：
10-30 00:31:51.494: D/CameraHal(1205): CameraHal setOverlay/1/00000000/00000000
10-30 00:31:51.494: E/CameraHal(1205): Trying to set overlay, but overlay is null!, line:3472
10-30 00:31:51.494: W/CameraService(1205): Overlay create failed - retrying
...
10-30 00:31:52.526: E/CameraService(1205): Overlay Creation Failed!
...
10-30 00:31:52.588: E/AndroidRuntime(5040): FATAL EXCEPTION: main
10-30 00:31:52.588: E/AndroidRuntime(5040): java.lang.RuntimeException: startPreview failed
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.hardware.Camera.startPreview(Native Method)
10-30 00:31:52.588: E/AndroidRuntime(5040): at com.matthewmitchell.nightcam.CameraSurfaceView.surfaceCreated(CameraSurfaceView.java:47)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.view.SurfaceView.updateWindow(SurfaceView.java:544)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.view.SurfaceView.dispatchDraw(SurfaceView.java:341)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.view.ViewGroup.drawChild(ViewGroup.java:1638)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1367)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.view.View.draw(View.java:6743)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.widget.FrameLayout.draw(FrameLayout.java:352)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.view.ViewGroup.drawChild(ViewGroup.java:1640)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1367)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.view.ViewGroup.drawChild(ViewGroup.java:1638)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1367)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.view.View.draw(View.java:6743)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.widget.FrameLayout.draw(FrameLayout.java:352)
10-30 00:31:52.588: E/AndroidRuntime(5040): at com.android.internal.policy.impl.PhoneWindow$DecorView.draw(PhoneWindow.java:1876)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.view.ViewRoot.draw(ViewRoot.java:1407)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.view.ViewRoot.performTraversals(ViewRoot.java:1163)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.view.ViewRoot.handleMessage(ViewRoot.java:1727)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.os.Handler.dispatchMessage(Handler.java:99)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.os.Looper.loop(Looper.java:123)
10-30 00:31:52.588: E/AndroidRuntime(5040): at android.app.ActivityThread.main(ActivityThread.java:4627)
10-30 00:31:52.588: E/AndroidRuntime(5040): at java.lang.reflect.Method.invokeNative(Native Method)
10-30 00:31:52.588: E/AndroidRuntime(5040): at java.lang.reflect.Method.invoke(Method.java:521)
10-30 00:31:52.588: E/AndroidRuntime(5040): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
10-30 00:31:52.588: E/AndroidRuntime(5040): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
10-30 00:31:52.588: E/AndroidRuntime(5040): at dalvik.system.NativeStart.main(Native Method)
这是Activity类：
public class NightCamActivity extends Activity {
private GLSurfaceView mGLView;
CameraSurfaceView surface_view;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Create a GLSurfaceView instance and set it
// as the ContentView for this Activity
Debug.out("Welcome");
surface_view = new CameraSurfaceView(this);
mGLView = new MySurfaceView(this);
setContentView(mGLView);
addContentView(surface_view, new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));
}
@Override
protected void onPause() {
super.onPause();
// The following call pauses the rendering thread.
// If your OpenGL application is memory intensive,
// you should consider de-allocating objects that
// consume significant memory here.
mGLView.onPause();
}
@Override
protected void onResume() {
super.onResume();
// The following call resumes a paused rendering thread.
// If you de-allocated graphic objects for onPause()
// this is a good place to re-allocate them.
mGLView.onResume();
}
}
MySurfaceView类：
class MySurfaceView extends GLSurfaceView{
public MySurfaceView(NightCamActivity context){
super(context);
// Create an OpenGL ES 2.0 context.
Debug.out("Mysurfaceview welcome");
setEGLContextClientVersion(2);
// Set the Renderer for drawing on the GLSurfaceView
MyRenderer renderer = new MyRenderer();
renderer.takeContext(context);
context.surface_view.renderer = renderer;
setRenderer(renderer);
}
}
CameraSurfaceView类：
public class CameraSurfaceView extends SurfaceView implements SurfaceHolder.Callback, PreviewCallback {
private Camera camera;
Camera.Size use_size;
MyRenderer renderer;
public CameraSurfaceView(Context context) {
super(context);
SurfaceHolder holder = getHolder();
holder.addCallback(this);
Debug.out("Init CSV");
camera = Camera.open();
}
public void surfaceCreated(SurfaceHolder holder) {
Debug.out("SC");
try {
camera.setPreviewDisplay(holder);
} catch (IOException e) {
Debug.out("Could not set preview display for camera.");
}
camera.setPreviewCallback(this);
}
public void surfaceDestroyed(SurfaceHolder holder) {
// Surface will be destroyed when we return, so stop the preview.
// Because the CameraDevice object is not a shared resource, it's very
// important to release it when the activity is paused.
try {
if (camera != null) {
camera.stopPreview();
camera.release();
}
} catch (Exception e) {
Debug.out("Camera release failure.");
}
}
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
Camera.Parameters parameters = camera.getParameters();
List<Camera.Size> supportedPreviewSizes = parameters.getSupportedPreviewSizes();
Camera.Size optimalPreviewSize = getOptimalPreviewSize(supportedPreviewSizes, w, h);
if (optimalPreviewSize != null) {
parameters.setPreviewSize(optimalPreviewSize.width, optimalPreviewSize.height);
camera.setParameters(parameters);
camera.startPreview();
}
}
static Camera.Size getOptimalPreviewSize(List<Camera.Size> sizes, int w, int h) {
final double ASPECT_TOLERANCE = 0.1;
final double MAX_DOWNSIZE = 1.5;
double targetRatio = (double) w / h;
if (sizes == null) return null;
Camera.Size optimalSize = null;
double minDiff = Double.MAX_VALUE;
int targetHeight = h;
// Try to find an size match aspect ratio and size
for (Camera.Size size : sizes) {
double ratio = (double) size.width / size.height;
double downsize = (double) size.width / w;
if (downsize > MAX_DOWNSIZE) {
//if the preview is a lot larger than our display surface ignore it
//reason - on some phones there is not enough heap available to show the larger preview sizes
continue;
}
if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE) continue;
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
// Cannot find the one match the aspect ratio, ignore the requirement
//keep the max_downsize requirement
if (optimalSize == null) {
minDiff = Double.MAX_VALUE;
for (Camera.Size size : sizes) {
double downsize = (double) size.width / w;
if (downsize > MAX_DOWNSIZE) {
continue;
}
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
}
//everything else failed, just take the closest match
if (optimalSize == null) {
minDiff = Double.MAX_VALUE;
for (Camera.Size size : sizes) {
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
}
return optimalSize;
}
public void onPreviewFrame(byte[] data, Camera arg1) {
Debug.out("PREVIEW FRAME:");
byte[] pixels = new byte[use_size.width * use_size.height * 3]; ;
decodeYUV420SP(pixels, data, use_size.width, use_size.height);
renderer.bindCameraTexture(pixels, use_size.width, use_size.height);
}
void decodeYUV420SP(byte[] rgb, byte[] yuv420sp, int width, int height) {
final int frameSize = width * height;
for (int j = 0, yp = 0; j < height; j++) {
int uvp = frameSize + (j >> 1) * width, u = 0, v = 0;
for (int i = 0; i < width; i++, yp++) {
int y = (0xff & ((int) yuv420sp[yp])) - 16;
if (y < 0){
y = 0;
}
if ((i & 1) == 0) {
v = (0xff & yuv420sp[uvp++]) - 128;
u = (0xff & yuv420sp[uvp++]) - 128;
}
int y1192 = 1192 * y;
int r = (y1192 + 1634 * v);
int g = (y1192 - 833 * v - 400 * u);
int b = (y1192 + 2066 * u);
if (r < 0){
r = 0;
}else if (r > 262143){
r = 262143;
}
if (g < 0){
g = 0;
}else if (g > 262143){
g = 262143;
}
if (b < 0){
b = 0;
}else if (b > 262143){
b = 262143;
}
rgb[yp*3] = (byte) (b << 6);
rgb[yp*3 + 1] = (byte) (b >> 2);
rgb[yp*3 + 2] = (byte) (b >> 10);
}
}
}
}
最后是MyRender类：
public class MyRenderer implements GLSurfaceView.Renderer{
private FloatBuffer vertices;
private FloatBuffer texcoords;
private int mProgram;
private int maPositionHandle;
private int gvTexCoordHandle;
private int gvSamplerHandle;
private static Context context;
int[] camera_texture;
public void onSurfaceCreated(GL10 unused, EGLConfig config) {
initShapes();
GLES20.glClearColor(0.0f, 1.0f, 0.2f, 1.0f);
Debug.out("Hello init.");
//Shaders
int vertexShader = 0;
int fragmentShader = 0;
try {
vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, readFile("vertex.vsh"));
fragmentShader = loadShader(GLES20.GL_FRAGMENT_SHADER, readFile("fragment.fsh"));
} catch (IOException e) {
Debug.out("The shaders could not be found.");
e.printStackTrace();
}
mProgram = GLES20.glCreateProgram(); // create empty OpenGL Program
GLES20.glAttachShader(mProgram, vertexShader); // add the vertex shader to program
GLES20.glAttachShader(mProgram, fragmentShader); // add the fragment shader to program
GLES20.glLinkProgram(mProgram); // creates OpenGL program executables
// get handles
maPositionHandle = GLES20.glGetAttribLocation(mProgram, "vPosition");
gvTexCoordHandle = GLES20.glGetAttribLocation(mProgram, "a_texCoord");
gvSamplerHandle = GLES20.glGetAttribLocation(mProgram, "s_texture");
GLES20.glPixelStorei(GLES20.GL_UNPACK_ALIGNMENT, 1);
camera_texture = null;
}
private void initShapes(){
float triangleCoords[] = {
// X, Y, Z
-1.0f, -1.0f, 0.0f,
1.0f, -1.0f, 0.0f,
-1.0f, 1.0f, 0.0f,
1.0f, 1.0f, 0.0f,
};
float texcoordf[] = {
// X, Y, Z
-1.0f,-1.0f,
1.0f,-1.0f,
-1.0f,1.0f,
1.0f,1.0f,
};
// initialize vertex Buffer for vertices
ByteBuffer vbb = ByteBuffer.allocateDirect(triangleCoords.length * 4);
vbb.order(ByteOrder.nativeOrder());// use the device hardware's native byte order
vertices = vbb.asFloatBuffer(); // create a floating point buffer from the ByteBuffer
vertices.put(triangleCoords); // add the coordinates to the FloatBuffer
vertices.position(0); // set the buffer to read the first coordinate
// initialize vertex Buffer for texcoords
vbb = ByteBuffer.allocateDirect(texcoordf.length * 4);
vbb.order(ByteOrder.nativeOrder());// use the device hardware's native byte order
texcoords = vbb.asFloatBuffer(); // create a floating point buffer from the ByteBuffer
texcoords.put(texcoordf); // add the coordinates to the FloatBuffer
texcoords.position(0); // set the buffer to read the first coordinate
}
private static String readFile(String path) throws IOException {
AssetManager assetManager = context.getAssets();
InputStream stream = assetManager.open(path);
try {
return new Scanner(stream).useDelimiter("\\A").next();
}
finally {
stream.close();
}
}
private int loadShader(int type, String shaderCode){
// create a vertex shader type (GLES20.GL_VERTEX_SHADER)
// or a fragment shader type (GLES20.GL_FRAGMENT_SHADER)
int shader = GLES20.glCreateShader(type);
// add the source code to the shader and compile it
GLES20.glShaderSource(shader, shaderCode);
GLES20.glCompileShader(shader);
return shader;
}
public void onDrawFrame(GL10 unused) {
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);
if(camera_texture == null){
return;
}
// Add program to OpenGL environment
GLES20.glUseProgram(mProgram);
// Prepare the triangle data
GLES20.glVertexAttribPointer(maPositionHandle, 3, GLES20.GL_FLOAT, false, 0, vertices);
GLES20.glVertexAttribPointer(gvTexCoordHandle, 2, GLES20.GL_FLOAT, false, 0, texcoords);
GLES20.glEnableVertexAttribArray(maPositionHandle);
GLES20.glEnableVertexAttribArray(gvTexCoordHandle);
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, camera_texture[0]);
GLES20.glUniform1i(gvSamplerHandle, 0);
// Draw the triangle
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
GLES20.glDisableVertexAttribArray(maPositionHandle);
GLES20.glDisableVertexAttribArray(gvTexCoordHandle);
}
public void onSurfaceChanged(GL10 unused, int width, int height) {
GLES20.glViewport(0, 0, width, height);
}
public void takeContext(Context ocontext) {
Debug.out("Take context");
context = ocontext;
}
void bindCameraTexture(byte[] data,int w,int h) {
byte[] pixels = new byte[256*256*3];
for(int x = 0;x < 256;x++){
for(int y = 0;x < 256;x++){
pixels[x*256+y] = data[x*w+y];
}
}
if (camera_texture==null){
camera_texture=new int[1];
}else{
GLES20.glDeleteTextures(1, camera_texture, 0);
}
GLES20.glGenTextures(1, camera_texture, 0);
int tex = camera_texture[0];
GLES20.glBindTexture(GL10.GL_TEXTURE_2D, tex);
GLES20.glTexImage2D(GL10.GL_TEXTURE_2D, 0, GL10.GL_RGB, 256, 256, 0, GL10.GL_RGB, GL10.GL_UNSIGNED_BYTE, ByteBuffer.wrap(pixels));
GLES20.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_LINEAR);
}
}
答案 0 :(得分：36)
我拿了你的代码并得到了和你一样的错误。但是，在调试时，在我看来预览可能会失败，因为看起来宽度和高度尺寸是错误的，但它不仅仅是切换它们的情况，因为我认为方向也起作用。
无论如何，我已用我自己的CameraSurfaceView替换（见下文），我认为它现在有效。没有例外，但屏幕是完全亮绿色（我想这可能是因为我没有vertex.vsh或fragment.vsh文件。
package stackOverflow.test;
import java.io.IOException;
import java.util.List;
import android.content.Context;
import android.hardware.Camera;
import android.hardware.Camera.Size;
import android.util.AttributeSet;
import android.util.Log;
import android.view.Display;
import android.view.Surface;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.ViewGroup;
import android.view.WindowManager;
public class CameraSurfaceView extends ViewGroup implements SurfaceHolder.Callback
{
private Size mPreviewSize;
private List<Size> mSupportedPreviewSizes;
private Context mContext;
private SurfaceView mSurfaceView;
private SurfaceHolder mHolder;
private final String TAG = "CameraSurfaceView";
private Camera mCamera;
private List<String> mSupportedFlashModes;
public CameraSurfaceView(Context context)
{
super(context);
mContext = context;
mCamera = Camera.open();
setCamera(mCamera);
mSurfaceView = new SurfaceView(context);
addView(mSurfaceView, 0);
mHolder = mSurfaceView.getHolder();
mHolder.addCallback(this);
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
mHolder.setKeepScreenOn(true);
}
public CameraSurfaceView(Context context, AttributeSet attrs)
{
super(context, attrs);
mContext = context;
}
public void setSupportedPreviewSizes(List<Size> supportedPreviewSizes)
{
mSupportedPreviewSizes = supportedPreviewSizes;
}
public Size getPreviewSize()
{
return mPreviewSize;
}
public void setCamera(Camera camera)
{
mCamera = camera;
if (mCamera != null)
{
mSupportedPreviewSizes = mCamera.getParameters().getSupportedPreviewSizes();
mSupportedFlashModes = mCamera.getParameters().getSupportedFlashModes();
// Set the camera to Auto Flash mode.
if (mSupportedFlashModes.contains(Camera.Parameters.FLASH_MODE_AUTO))
{
Camera.Parameters parameters = mCamera.getParameters();
parameters.setFlashMode(Camera.Parameters.FLASH_MODE_AUTO);
mCamera.setParameters(parameters);
}
}
requestLayout();
}
@Override
public void surfaceDestroyed(SurfaceHolder holder)
{
// Surface will be destroyed when we return, so stop the preview.
if (mCamera != null)
{
mCamera.stopPreview();
}
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height)
{
// Now that the size is known, set up the camera parameters and begin
// the preview.
if (mCamera != null)
{
Camera.Parameters parameters = mCamera.getParameters();
Size previewSize = getPreviewSize();
parameters.setPreviewSize(previewSize.width, previewSize.height);
mCamera.setParameters(parameters);
mCamera.startPreview();
}
}
@Override
public void surfaceCreated(SurfaceHolder holder)
{
// The Surface has been created, acquire the camera and tell it where
// to draw.
try
{
if (mCamera != null)
{
mCamera.setPreviewDisplay(holder);
}
}
catch (IOException exception)
{
Log.e(TAG, "IOException caused by setPreviewDisplay()", exception);
}
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
{
final int width = resolveSize(getSuggestedMinimumWidth(), widthMeasureSpec);
final int height = resolveSize(getSuggestedMinimumHeight(), heightMeasureSpec);
setMeasuredDimension(width, height);
if (mSupportedPreviewSizes != null)
{
mPreviewSize = getOptimalPreviewSize(mSupportedPreviewSizes, width, height);
}
}
@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom)
{
if (changed)
{
final View cameraView = getChildAt(0);
final int width = right - left;
final int height = bottom - top;
int previewWidth = width;
int previewHeight = height;
if (mPreviewSize != null)
{
Display display = ((WindowManager)mContext.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
switch (display.getRotation())
{
case Surface.ROTATION_0:
previewWidth = mPreviewSize.height;
previewHeight = mPreviewSize.width;
mCamera.setDisplayOrientation(90);
break;
case Surface.ROTATION_90:
previewWidth = mPreviewSize.width;
previewHeight = mPreviewSize.height;
break;
case Surface.ROTATION_180:
previewWidth = mPreviewSize.height;
previewHeight = mPreviewSize.width;
break;
case Surface.ROTATION_270:
previewWidth = mPreviewSize.width;
previewHeight = mPreviewSize.height;
mCamera.setDisplayOrientation(180);
break;
}
}
final int scaledChildHeight = previewHeight * width / previewWidth;
cameraView.layout(0, height - scaledChildHeight, width, height);
}
}
private Size getOptimalPreviewSize(List<Size> sizes, int width, int height)
{
Size optimalSize = null;
final double ASPECT_TOLERANCE = 0.1;
double targetRatio = (double) height / width;
// Try to find a size match which suits the whole screen minus the menu on the left.
for (Size size : sizes)
{
if (size.height != width) continue;
double ratio = (double) size.width / size.height;
if (ratio <= targetRatio + ASPECT_TOLERANCE && ratio >= targetRatio - ASPECT_TOLERANCE)
{
optimalSize = size;
}
}
// If we cannot find the one that matches the aspect ratio, ignore the requirement.
if (optimalSize == null)
{
// TODO : Backup in case we don't get a size.
}
return optimalSize;
}
public void previewCamera()
{
try
{
mCamera.setPreviewDisplay(mHolder);
mCamera.startPreview();
}
catch(Exception e)
{
Log.d(TAG, "Cannot start preview.", e);
}
}
/*public void onPreviewFrame(byte[] data, Camera arg1) {
Log.d("CameraSurfaceView", "PREVIEW FRAME:");
byte[] pixels = new byte[use_size.width * use_size.height * 3]; ;
decodeYUV420SP(pixels, data, use_size.width, use_size.height);
renderer.bindCameraTexture(pixels, use_size.width, use_size.height);
}*/
void decodeYUV420SP(byte[] rgb, byte[] yuv420sp, int width, int height) {
final int frameSize = width * height;
for (int j = 0, yp = 0; j < height; j++) {
int uvp = frameSize + (j >> 1) * width, u = 0, v = 0;
for (int i = 0; i < width; i++, yp++) {
int y = (0xff & ((int) yuv420sp[yp])) - 16;
if (y < 0){
y = 0;
}
if ((i & 1) == 0) {
v = (0xff & yuv420sp[uvp++]) - 128;
u = (0xff & yuv420sp[uvp++]) - 128;
}
int y1192 = 1192 * y;
int r = (y1192 + 1634 * v);
int g = (y1192 - 833 * v - 400 * u);
int b = (y1192 + 2066 * u);
if (r < 0){
r = 0;
}else if (r > 262143){
r = 262143;
}
if (g < 0){
g = 0;
}else if (g > 262143){
g = 262143;
}
if (b < 0){
b = 0;
}else if (b > 262143){
b = 262143;
}
rgb[yp*3] = (byte) (b << 6);
rgb[yp*3 + 1] = (byte) (b >> 2);
rgb[yp*3 + 2] = (byte) (b >> 10);
}
}
}
}
你会注意到我注释了你的onPreviewFrame（）方法只是为了让它运行而且行context.surface_view.renderer = renderer。
我不熟悉OpenGL库，但也许这足以让你重新开始。
答案 1 :(得分：17)
我遇到了同样的问题，删除/播放预览大小设置对我来说不起作用。我通过下一行代码修复它：
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
现在它适用于我！
答案 2 :(得分：7)
在您的例外之前检查您的logcat是否有类似的内容：
11-02 09:25:44.305: ERROR/QualcommCameraHardware(56): failed to construct master heap for pmem pool /dev/pmem_adsp
11-02 09:25:44.305: ERROR/QualcommCameraHardware(56): initPreview X: could not initialize preview heap.
11-02 09:25:44.305: ERROR/QualcommCameraHardware(56): startPreview X initPreview failed. Not starting preview.
当我尝试将预览尺寸设置为1024x768时，这种情况会在我的手机横向上发生。 getSupportedPreviewSizes（）方法表示支持此大小，但操作系统似乎无法为此预览分配足够的内存。设置较小的尺寸确实有效。
另外，请尝试下面的代码。您应该从surfaceChanged（）方法调用startPreview（），此时SurfaceView的尺寸已知。从surfaceCreated（）调用它太早了。
使用此选项确定特定尺寸SurfaceView的最佳预览尺寸（改编自Google CameraPreview示例）
static Size getOptimalPreviewSize(List<Size> sizes, int w, int h) {
final double ASPECT_TOLERANCE = 0.1;
final double MAX_DOWNSIZE = 1.5;
double targetRatio = (double) w / h;
if (sizes == null) return null;
Size optimalSize = null;
double minDiff = Double.MAX_VALUE;
int targetHeight = h;
// Try to find an size match aspect ratio and size
for (Size size : sizes) {
double ratio = (double) size.width / size.height;
double downsize = (double) size.width / w;
if (downsize > MAX_DOWNSIZE) {
//if the preview is a lot larger than our display surface ignore it
//reason - on some phones there is not enough heap available to show the larger preview sizes
continue;
}
if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE) continue;
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
// Cannot find the one match the aspect ratio, ignore the requirement
//keep the max_downsize requirement
if (optimalSize == null) {
minDiff = Double.MAX_VALUE;
for (Size size : sizes) {
double downsize = (double) size.width / w;
if (downsize > MAX_DOWNSIZE) {
continue;
}
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
}
//everything else failed, just take the closest match
if (optimalSize == null) {
minDiff = Double.MAX_VALUE;
for (Size size : sizes) {
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
}
return optimalSize;
}
您可以使用surfaceChanged（）方法调用它，如下所示：
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
Camera.Parameters parameters = camera.getParameters();
List<Size> supportedPreviewSizes = parameters.getSupportedPreviewSizes();
Size optimalPreviewSize = getOptimalPreviewSize(supportedPreviewSizes, w, h);
if (optimalPreviewSize != null) {
parameters.setPreviewSize(optimalPreviewSize.width, optimalPreviewSize.height);
camera.setParameters(parameters);
camera.startPreview();
}
}
答案 3 :(得分：7)
尝试在initCamera（）中设置Surface的类型。
private void initCamera() {
mCamSV = (SurfaceView)findViewById(R.id.surface_camera);
mCamSH = mCamSV.getHolder();
mCamSH.addCallback(this);
**mCamSH.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);**
}
编辑1
我正在使用android 2.2 sdk复制所有适用于我的文件
活动
package com.stack.camera;
import java.io.IOException;
import android.app.Activity;
import android.hardware.Camera;
import android.os.Bundle;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.WindowManager;
import android.widget.FrameLayout;
public class CameraStackActivity extends Activity implements SurfaceHolder.Callback {
private Camera mCam;
private SurfaceView mCamSV;
private SurfaceHolder mCamSH;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.main);
initCamera();
}
@Override
public void onDestroy() {
stopCamera();
}
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
startCamera(holder, width, height);
}
public void surfaceCreated(SurfaceHolder holder) {
// TODO Auto-generated method stub
mCam = Camera.open();
try {
mCam.setPreviewDisplay(holder);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void surfaceDestroyed(SurfaceHolder holder) {
// TODO Auto-generated method stub
}
private void initCamera() {
mCamSV = (SurfaceView)findViewById(R.id.surface_camera);
mCamSH = mCamSV.getHolder();
mCamSH.addCallback(this);
mCamSH.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}
private void startCamera(SurfaceHolder sh, int width, int height) {
Camera.Parameters p = mCam.getParameters();
// Camera.Size s = p.getSupportedPreviewSizes().get(0);
p.setPreviewSize(width, height);
mCam.setParameters(p);
try {
mCam.setPreviewDisplay(sh);
} catch (Exception e) {
}
mCam.startPreview();
}
private void stopCamera() {
mCamSH.removeCallback(this);
mCam.stopPreview();
mCam.release();
}
}
布局
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="fill_parent"
android:layout_height="fill_parent">
<SurfaceView android:id="@+id/surface_camera"
android:layout_width="fill_parent" android:layout_height="fill_parent" />
</FrameLayout>
清单文件
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.stack.camera"
android:versionCode="1"
android:versionName="1.0">
<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" />
<uses-feature android:name="android.hardware.camera.autofocus" />
<application android:icon="@drawable/icon" android:label="@string/app_name">
<activity android:name="CameraStackActivity"
android:label="@string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
答案 4 :(得分：1)
简单解决方案：在CameraSurfaceView课程中添加以下行：
holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
以下这些行：
SurfaceHolder holder = getHolder();
holder.addCallback(this);
答案 5 :(得分：1)
与OP问题没有关系，但不过......
我看到以下问题给了我java.io.IOException: setPreviewDisplay failed：
如果同时执行视频和照片，则有两个功能， camera.unlock（）和 camera.reconnect（）。在录制视频之前，您必须 camera.unlock（），然后在拍照前使用 camera.reconnect（）。
答案 6 :(得分：0)
我对这个游戏有点迟了，但我正在运行cordova，并且有两个插件试图同时注册相机。
不确定这是否会对除我以外的任何人使用。