相机 2 预览被拉伸答案

【问题标题】：Camera 2 Preview is stretched相机 2 预览被拉伸
【发布时间】：2019-05-14 06:14:54
【问题描述】：

我目前正在使用 Camera2 API 制作一个 android 应用程序。我遇到了 AutoFitTextureView 的问题，图像显示为拉伸。我的 AutoFitTextureView 代码如下

public class AutoFitTextureView extends TextureView {
private int mRatioWidth = 0;
private int mRatioHeight = 0;
private boolean mWithMargin = false;
public AutoFitTextureView(Context context) {
    this(context, null);
}
public AutoFitTextureView(Context context, AttributeSet attrs) {
    this(context, attrs, 0);
}
public AutoFitTextureView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
}

public void setAspectRatio(int width, int height) {
    if (width < 0 || height < 0) {
        throw new IllegalArgumentException("Size cannot be negative.");
    }
    mRatioWidth = width;
    mRatioHeight = height;
    requestLayout();
}

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    int width = MeasureSpec.getSize(widthMeasureSpec);
    int height = MeasureSpec.getSize(heightMeasureSpec);
    if (0 == mRatioWidth || 0 == mRatioHeight) {
        setMeasuredDimension(width, height);
    } else {
        if (width < height * mRatioWidth / mRatioHeight) {
            setMeasuredDimension(width, width * mRatioHeight / mRatioWidth);
        } else {
            setMeasuredDimension(height * mRatioWidth / mRatioHeight, height);
        }
    }
}

XML 代码-

拉伸图像：

我正在使用的 XML 代码如下所示，预览即将拉长-

 <com.qopius.AutoFitTextureViewNew
        android:id="@+id/texture"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
         />

【问题讨论】：

仍在寻找有效的答案

标签： android android-camera2 textureview

【解决方案1】：

试试这个代码

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    int width = MeasureSpec.getSize(widthMeasureSpec);
    int height = MeasureSpec.getSize(heightMeasureSpec);
    if (0 == mRatioWidth || 0 == mRatioHeight) {
        setMeasuredDimension(width, height);
    } else {
            if (width < height * mRatioWidth / mRatioHeight) {
            if (width > height * mRatioWidth / mRatioHeight) {
                setMeasuredDimension(width, width * mRatioHeight / mRatioWidth);
            } else {
                setMeasuredDimension(height * mRatioWidth / mRatioHeight, height);
}
}

【讨论】：

请同时分享 AutoFitTextureView XML
@Bjha 尝试将其设为 wrap_content
试过了，但没有任何反应图片被拉长了

【解决方案2】：

试试这个

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    int width = MeasureSpec.getSize(widthMeasureSpec);
    int height = MeasureSpec.getSize(heightMeasureSpec);
    if (0 == mRatioWidth || 0 == mRatioHeight) {
        setMeasuredDimension(width, height);
    } else {
        if (width > height * mRatioWidth / mRatioHeight) {
            setMeasuredDimension(width, width * mRatioHeight / mRatioWidth);
        } else {
            setMeasuredDimension(height * mRatioWidth / mRatioHeight, height);
        }
    }
}

【讨论】：

【解决方案3】：

您需要将 AutoFitTextureView 放置在允许其调整大小的父视图/容器中。如果父视图不允许这样做，无论您在其 onMeasure 中做什么，它都会调整纹理视图的大小。

例如，Camera2Basic 示例将 AutoFitTextureView 放置在 RelativeLayout 中：

https://github.com/googlesamples/android-Camera2Basic/blob/master/Application/src/main/res/layout/fragment_camera2_basic.xml

【讨论】：

我已将 AutoFitTextureView 放在 relativeLayout 中，并为其指定宽度和高度匹配父级，但仍然无法调整预览，并且似乎被挤压了

【解决方案4】：

1.) 你的纵向除数和除数错误地颠倒了：

setMeasuredDimension(width, width * mRatioHeight / mRatioWidth);

2.) AutoFitTextureView 示例在 onMeasure(..) 中区分纹理方向的逻辑具有误导性：

if (width > height * mRatioWidth / mRatioHeight)

虽然它在 4:3 左右（模拟器、S2、S4）运行良好，但在更大的纵横比下会失败（Essential PH-1）。将纹理方向添加到 setAspectRatio(..) 方法可提供所需的信息。

注意：下面的示例忽略了 180° 和 270° 的方向。

import android.util.AttributeSet;
class AutoFitTextureView extends TextureView {
    private int mRatioWidth = 0;
    private int mRatioHeight = 0;
    private int mTextureOrientation = 0;

    public AutoFitTextureView(Context context) {
        this(context, null);
    }
    public AutoFitTextureView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }
    public AutoFitTextureView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }
    public void setAspectRatio(int width, int height, int textureOrientation) {
        if ( width < 0 || height < 0 ) {
            throw new IllegalArgumentException("Size cannot be negative.");
        }
        mRatioWidth = width;
        mRatioHeight = height;
        mTextureOrientation = textureOrientation;
        requestLayout();
    }
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        int width = MeasureSpec.getSize(widthMeasureSpec);
        int height = MeasureSpec.getSize(heightMeasureSpec);
        if ( 0 == mRatioWidth || 0 == mRatioHeight ) {
            setMeasuredDimension(width, height);
        } else {
            if ( mTextureOrientation == 0 ) { // 0 == portrait, 1 == landscape
                setMeasuredDimension(width, width * mRatioWidth/mRatioHeight);
            } else {
                setMeasuredDimension(height * mRatioWidth/mRatioHeight, height);
            }
        }
    }
}

【讨论】：