如何解决Android Camera2预览被拉伸
我正在尝试学习Camera2 API,并且已经构建了一个简单的相机应用程序仅用于拍照,但是我面临的问题是预览在某些分辨率下会被拉伸。我浏览了许多不同的帖子,所有这些帖子都暗示我的宽高比可能是错误的,但是我使用了Google推荐的AutoFitTextureView,但正确的宽高比仍然使我的预览被拉伸了。我从playstore下载了一些开源相机应用程序,其中很多也与我的前置相机(EXCEPT OPEN CAMERA)存在相同的问题,但有趣的是我在另一台设备上使用了相同的应用程序,并且预览效果绝对完美。所以最后我决定用不同的分辨率测试我的应用程序并观察结果,但是我找不到任何模式可以帮助任何人使我从中受益吗?
my device display size is 720x1280
Front camera results:
SurfaceTexture AutoFitTextureView Result
buffer size size
2576x1932 720x960 Normal
2560x1440 720x1280 Normal
2048x1536 720x960 Normal
2048x1152 720x1280 Normal
1920x1920 720x720 Normal
1920x1080 720x1280 Normal
1440x1080 720x960 Horizontally Stretched
1280x720 720x1280 Horizontally Stretched
1072x1072 720x720 Normal
960x720 720x960 Normal
720x480 720x1080 Horizontally Stretched
640x480 720x960 Horizontally Stretched
352x288 720x880 Normal
320x240 720x960 Normal
256x144 720x1280 Horizontally Stretched
176x144 720x880 Normal
解决方法
Camera2作为初学者很难学习。考虑使用功能最强大的相机库。这是我发现的最好的一个:https://camerakit.io/docs。这真的很容易,它将解决您现在面临的所有问题。
(请注意,我不是这个项目的所有者,无论如何我都不会推广它。我已经尝试使用camera2 API,但确实很难,这就是为什么我建议了一个更简单的解决方案。
这实际上可能是设备错误-摄像头实现无法从完整的传感器尺寸进行缩放。这种情况通常发生在大多数应用程序不使用的异常大小上。
在您的情况下,相机管线的某些部分可能会将1440x1080视为1920x1080,从而导致拉伸。有时,可以通过添加第二种输出(例如,JPEG)以不同的分辨率(有时甚至是相同的分辨率)来“修复”。
当然,您的代码(或AutoFitTextureView)中仍然可能存在逻辑错误。但是,这些很难为您提供有用的建议-这是检查所有布局并逐步缩放数学的问题。
您还可以尝试使用Google的官方相机支持库CameraX。它处于测试阶段,可以很好地用于基本用例,例如预览,静止图像捕获和图像分析。
,他们的关键是在您渲染预览的 TextureView 上设置正确的变换。 TextureView 的宽度和高度设置为匹配其父布局。
TextureView textureView;
void setTextureTransform(CameraCharacteristics characteristics) {
Size previewSize = getPreviewSize(characteristics);
int width = previewSize.getWidth();
int height = previewSize.getHeight();
int sensorOrientation = getCameraSensorOrientation(characteristics);
// Indicate the size of the buffer the texture should expect
textureView.getSurfaceTexture().setDefaultBufferSize(width,height);
// Save the texture dimensions in a rectangle
RectF viewRect = new RectF(0,textureView.getWidth(),textureView.getHeight());
// Determine the rotation of the display
float rotationDegrees = 0;
try {
rotationDegrees = (float)getDisplayRotation();
} catch (Exception ignored) {
}
float w,h;
if ((sensorOrientation - rotationDegrees) % 180 == 0) {
w = width;
h = height;
} else {
// Swap the width and height if the sensor orientation and display rotation don't match
w = height;
h = width;
}
float viewAspectRatio = viewRect.width()/viewRect.height();
float imageAspectRatio = w/h;
final PointF scale;
// This will make the camera frame fill the texture view,if you'd like to fit it into the view swap the "<" sign for ">"
if (viewAspectRatio < imageAspectRatio) {
// If the view is "thinner" than the image constrain the height and calculate the scale for the texture width
scale = new PointF((viewRect.height() / viewRect.width()) * ((float) height / (float) width),1f);
} else {
scale = new PointF(1f,(viewRect.width() / viewRect.height()) * ((float) width / (float) height));
}
if (rotationDegrees % 180 != 0) {
// If we need to rotate the texture 90º we need to adjust the scale
float multiplier = viewAspectRatio < imageAspectRatio ? w/h : h/w;
scale.x *= multiplier;
scale.y *= multiplier;
}
Matrix matrix = new Matrix();
// Set the scale
matrix.setScale(scale.x,scale.y,viewRect.centerX(),viewRect.centerY());
if (rotationDegrees != 0) {
// Set rotation of the device isn't upright
matrix.postRotate(0 - rotationDegrees,viewRect.centerY());
}
// Transform the texture
textureView.setTransform(matrix);
}
int getDisplayRotation() {
switch (textureView.getDisplay().getRotation()) {
case Surface.ROTATION_0:
default:
return 0;
case Surface.ROTATION_90:
return 90;
case Surface.ROTATION_180:
return 180;
case Surface.ROTATION_270:
return 270;
}
}
Size getPreviewSize(CameraCharacteristics characteristics) {
StreamConfigurationMap map = characteristics.get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP);
Size[] previewSizes = map.getOutputSizes(SurfaceTexture.class);
// TODO: decide on which size fits your view size the best
return previewSizes[0];
}
int getCameraSensorOrientation(CameraCharacteristics characteristics) {
Integer cameraOrientation = characteristics.get(CameraCharacteristics.SENSOR_ORIENTATION);
return (360 - (cameraOrientation != null ? cameraOrientation : 0)) % 360;
}