Question

我在使用目标sdk 22构建的应用程序中使用自定义相机。我在许多设备上通过我的应用程序测试了相机，包括三星S5，三星Note 4和华为登高伙伴7，图像预览很好。

但是当我在Samsung Galaxy S4（Android 5.0.1）中通过我的应用程序打开相机时，我的相机预览失真了。以下是预览图片：

我在stackoverflow上看过很多帖子，但是他们在捕获图像之后发现了我的问题是在捕获图片之前。

以下是我用于预览的代码：

surfaceChanged方法

     public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
        try {
         holder.addCallback(this);
            holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
            Camera.Parameters parameters = camera.getParameters();
            try {
            List<Camera.Size> supportedSizes = null;
            supportedSizes = Compatibility.getSupportedPreviewSizes(parameters);

            //preview form factor
            float ff = (float)w/h;
            Log.d("", "Screen res: w:"+ w + " h:" + h + " aspect ratio:" + ff);

            //holder for the best form factor and size
            float bff = 0;
            int bestw = 0;
            int besth = 0;
            Iterator<Camera.Size> itr = supportedSizes.iterator();

            while(itr.hasNext()) {
                Camera.Size element = itr.next();
                //current form factor
                float cff = (float)element.width/element.height;

                Log.d("Camera", "Candidate camera element: w:"+ element.width + " h:" + element.height + " aspect ratio:" + cff);
                int currentRes = element.width*element.height;
                //ff = Asp ratio of current Screen
                // cff =  Asp ratio of current Size from Size list
                // bff =  Asp ratio of current best aspect ratio selected
                if ((Math.abs(ff-cff) <= Math.abs(ff-bff) ) ) {
                      bff=cff;
                      bestw = element.width;
                      besth = element.height;
                     }
            } 

            Log.d("Camera", "Chosen camera element: w:"+ bestw + " h:" + besth + " aspect ratio:" + bff);
            if ((bestw == 0) || (besth == 0)){
                Log.d("Camera", "Using default camera parameters!");
                bestw = 480;
                besth = 320;
                Log.d("Camera","Using default camera parameters! aspect ratio "+480/320);
            }
            parameters.setPreviewSize(bestw, besth);

            //Handling camera angle
            switch(this.getWindowManager().getDefaultDisplay().getRotation()){
            case 0:
                camera.setDisplayOrientation(90);
                break;
            case 1:
                camera.setDisplayOrientation(0);
                break;
            case 2:
            case 3:
                camera.setDisplayOrientation(180);
                break;
            }

        } catch (Exception ex) {
            parameters.setPreviewSize(480 , 320);
        }

        camera.setParameters(parameters);
        camera.startPreview();
    } catch (Exception ex) {
        ex.printStackTrace();
    }
}

Compatibility.getSupportedPreviewSizes（参数）方法

 @SuppressWarnings("unchecked")
 public static List<Camera.Size> getSupportedPreviewSizes(Camera.Parameters params) {
List<Camera.Size> retList = null;

try {
    Object retObj = mParameters_getSupportedPreviewSizes.invoke(params);
    if (retObj != null) {
        retList = (List<Camera.Size>)retObj;
    }
}
catch (InvocationTargetException ite) {
    /* unpack original exception when possible */
    Throwable cause = ite.getCause();
    if (cause instanceof RuntimeException) {
        throw (RuntimeException) cause;
    } else if (cause instanceof Error) {
        throw (Error) cause;
    } else {
        /* unexpected checked exception; wrap and re-throw */
        throw new RuntimeException(ite);
    }
} catch (IllegalAccessException ie) {
    //System.err.println("unexpected " + ie);
}
return retList;
}

我会感激任何帮助。

提前致谢。

Answer 1

在Samsung Note IV上，我意识到你不应该使用setPreviewSize（），即使从getSupportedPreviewSizes()获得的大小应该合法且可用。

三星的低级相机软件是一个尴尬的错误。 Uncool，三星！它仅使用某些设备进行复制。

但是，拍摄仍然无可挑剔。所以，这是我的代码：

    Camera.Parameters parameters = camera.getParameters();

    boolean currentPreviewSettingsAreValid = parameters != null;
    currentPreviewSettingsAreValid = currentPreviewSettingsAreValid && parameters.getPreviewSize() != null;
    currentPreviewSettingsAreValid = currentPreviewSettingsAreValid && parameters.getPreviewSize().width > 0 && parameters.getPreviewSize().height > 0;

    if (parameters != null && !currentPreviewSettingsAreValid) {
        Camera.Size bestSize = getBestSizeOfSupported(parameters.getSupportedPreviewSizes(), width, height);

        if (bestSize != null) {
            parameters.setPreviewSize(bestSize.width, bestSize.height);
        }
    }

希望它可以帮助任何人

Android三星Galaxy S4自定义相机预览扭曲

1 个答案: