我创建了一个CameraSurfaceView类，它提供了实现相机预览的逻辑。在我尝试的设备上一切正常。 Nexus 5，Nexus 5X，Nexus 6P甚至三星Galaxy S5。
但由于某些原因在三星Galaxy S6 Edge上，我得到了
的运行时例外android.hardware.Camera.native_setParameters（原生方法）
我已将其缩小到类
中的以下内容parameters.setPictureSize（mPreviewSize.width，mPreviewSize.height）;
这是我的班级：
public class CameraSurfaceView extends SurfaceView implements SurfaceHolder.Callback {
private Camera mCamera;
private SurfaceHolder mSurfaceHolder;
private List<Camera.Size> mSupportedPreviewSizes;
private Camera.Size mPreviewSize;
public CameraSurfaceView(Context context, Camera camera) {
super(context);
mCamera = camera;
mSurfaceHolder = getHolder();
mSurfaceHolder.addCallback(this);
mSupportedPreviewSizes = mCamera.getParameters().getSupportedPreviewSizes();
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
if (mSurfaceHolder.getSurface() == null) {
// preview surface does not exist
return;
}
try {
// stop preview before making changes
mCamera.stopPreview();
} catch (Exception e) {
Timber.e(e, e.getMessage());
}
// set preview size and make any resize, rotate or reformatting changes here
// start preview with new settings
try {
Camera.Parameters parameters = mCamera.getParameters();
parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
parameters.setPictureSize(mPreviewSize.width, mPreviewSize.height);
if (parameters.getSupportedFocusModes()
.contains(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE)) {
parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE);
}
mCamera.setParameters(parameters);
mCamera.setPreviewDisplay(mSurfaceHolder);
mCamera.startPreview();
} catch (Exception e) {
Timber.e(e, "Error starting camera preview: " + e.getMessage());
}
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
final int width = resolveSize(getSuggestedMinimumWidth(), widthMeasureSpec);
final int height = resolveSize(getSuggestedMinimumHeight(), heightMeasureSpec);
if (mSupportedPreviewSizes != null) {
mPreviewSize = getOptimalPreviewSize(mSupportedPreviewSizes, width, height);
}
float ratio;
if (mPreviewSize.height >= mPreviewSize.width) {
ratio = (float) mPreviewSize.height / (float) mPreviewSize.width;
} else {
ratio = (float) mPreviewSize.width / (float) mPreviewSize.height;
}
// One of these methods should be used, second method squishes preview slightly
setMeasuredDimension(width, (int) (width * ratio));
// setMeasuredDimension((int) (width * ratio), height);
}
private Camera.Size getOptimalPreviewSize(List<Camera.Size> sizes, int w, int h) {
final double aspectTolerance = 0.1;
double targetRatio = (double) h / w;
if (sizes == null) {
return null;
}
Camera.Size optimalSize = null;
double minDiff = Double.MAX_VALUE;
int targetHeight = h;
for (Camera.Size size : sizes) {
double ratio = (double) size.height / size.width;
if (Math.abs(ratio - targetRatio) > aspectTolerance) {
continue;
}
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
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;
}
}
如何正确设置此设备或其他具有相同问题的图片尺寸？
有没有人有一个适用于大多数设备的Camera SurfaceView逻辑的好例子？
感谢。
答案 0 :(得分：0)
原来我使用supportedPreviewSizes设置图片大小而不是相机参数中的supportedPictureSizes。
下面是我的新CameraSurfaceView类：
public class CameraSurfaceView extends SurfaceView implements SurfaceHolder.Callback {
private Camera mCamera;
private SurfaceHolder mSurfaceHolder;
private List<Camera.Size> mSupportedPreviewSizes;
private List<Camera.Size> mSupportedPictureSizes;
private Camera.Size mPreviewSize;
private Camera.Size mPictureSize;
public CameraSurfaceView(Context context, Camera camera) {
super(context);
mSurfaceHolder = getHolder();
mSurfaceHolder.addCallback(this);
mCamera = camera;
Camera.Parameters parameters = mCamera.getParameters();
mSupportedPreviewSizes = parameters.getSupportedPreviewSizes();
mSupportedPictureSizes = parameters.getSupportedPictureSizes();
if (parameters.getSupportedFocusModes()
.contains(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE)) {
parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE);
}
mCamera.setParameters(parameters);
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
if (mSurfaceHolder.getSurface() == null) {
// preview surface does not exist
return;
}
try {
// stop preview before making changes
mCamera.stopPreview();
} catch (Exception e) {
Timber.e(e, e.getMessage());
}
// set preview size and make any resize, rotate or reformatting changes here
// start preview with new settings
try {
Camera.Parameters parameters = mCamera.getParameters();
parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
parameters.setPictureSize(mPictureSize.width, mPictureSize.height);
mCamera.setParameters(parameters);
mCamera.setPreviewDisplay(mSurfaceHolder);
mCamera.startPreview();
} catch (Exception e) {
Timber.e(e, "Error starting camera preview: " + e.getMessage());
}
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
final int width = resolveSize(getSuggestedMinimumWidth(), widthMeasureSpec);
final int height = resolveSize(getSuggestedMinimumHeight(), heightMeasureSpec);
if (mSupportedPreviewSizes != null) {
mPreviewSize = getOptimalPreviewSize(mSupportedPreviewSizes, width, height);
}
if (mSupportedPictureSizes != null) {
mPictureSize = getOptimalPreviewSize(mSupportedPictureSizes, mPreviewSize.width,
mPreviewSize.height);
}
float ratio;
if (mPreviewSize.height >= mPreviewSize.width) {
ratio = (float) mPreviewSize.height / (float) mPreviewSize.width;
} else {
ratio = (float) mPreviewSize.width / (float) mPreviewSize.height;
}
setMeasuredDimension(width, (int) (width * ratio));
}
private Camera.Size getOptimalPreviewSize(List<Camera.Size> sizes, int w, int h) {
final double aspectTolerance = 0.1;
double targetRatio = (double) h / w;
if (sizes == null) {
return null;
}
Camera.Size optimalSize = null;
double minDiff = Double.MAX_VALUE;
int targetHeight = h;
for (Camera.Size size : sizes) {
double ratio = (double) size.height / size.width;
if (Math.abs(ratio - targetRatio) > aspectTolerance) {
continue;
}
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
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;
}
}