如何在 Android 中调整图像大小？

Posted 2023-02-14

【中文标题】如何在 Android 中调整图像大小？

【英文标题】：How to resize Image in Android?

【发布时间】：2012-05-11 22:07:49

【问题描述】：

我正在创建一个应用程序并想设置一个画廊视图。我不希望画廊视图中的图像是全尺寸的。

【问题讨论】：

如果图片你想缩小尺寸还是只想显示小？

【参考方案1】：

试试：

Bitmap yourBitmap;
Bitmap resized = Bitmap.createScaledBitmap(yourBitmap, newWidth, newHeight, true);

或：

resized = Bitmap.createScaledBitmap(yourBitmap,(int)(yourBitmap.getWidth()*0.8), (int)(yourBitmap.getHeight()*0.8), true);

【参考方案2】：

public Bitmap resizeBitmap(String photoPath, int targetW, int targetH) 
    BitmapFactory.Options bmOptions = new BitmapFactory.Options();
    bmOptions.inJustDecodeBounds = true;
    BitmapFactory.decodeFile(photoPath, bmOptions);
    int photoW = bmOptions.outWidth;
    int photoH = bmOptions.outHeight;

    int scaleFactor = 1;
    if ((targetW > 0) || (targetH > 0)) 
            scaleFactor = Math.min(photoW/targetW, photoH/targetH);        
    

    bmOptions.inJustDecodeBounds = false;
    bmOptions.inSampleSize = scaleFactor;
    bmOptions.inPurgeable = true; //Deprecated API 21

    return BitmapFactory.decodeFile(photoPath, bmOptions);            

【参考方案3】：

捕获图像并调整其大小。

Bitmap image2 = (Bitmap) data.getExtras().get("data");
img.setImageBitmap(image2);
String incident_ID = IncidentFormActivity.incident_id;

imagepath="/sdcard/RDMS/"+incident_ID+ x + ".PNG";
File file = new File(imagepath);
    try 
        double xFactor = 0;
        double width = Double.valueOf(image2.getWidth());
        Log.v("WIDTH", String.valueOf(width));
        double height = Double.valueOf(image2.getHeight());
        Log.v("height", String.valueOf(height));
        if(width>height)
        xFactor = 841/width;
    
    else
        xFactor = 595/width;
    


Log.v("Nheight", String.valueOf(width*xFactor));
Log.v("Nweight", String.valueOf(height*xFactor));
int Nheight = (int) ((xFactor*height));
int NWidth =(int) (xFactor * width) ; 

bm = Bitmap.createScaledBitmap( image2,NWidth, Nheight, true);
file.createNewFile();
FileOutputStream ostream = new FileOutputStream(file);
bm.compress(CompressFormat.PNG, 100, ostream);
ostream.close(); 

【参考方案4】：

您可以使用 Matrix 调整相机图像的大小 ....

BitmapFactory.Options options=new BitmapFactory.Options();
InputStream is = getContentResolver().openInputStream(currImageURI);
bm = BitmapFactory.decodeStream(is,null,options);
int Height = bm.getHeight();
int Width = bm.getWidth();
int newHeight = 300;
int newWidth = 300;
float scaleWidth = ((float) newWidth) / Width;
float scaleHeight = ((float) newHeight) / Height;
Matrix matrix = new Matrix();
matrix.postScale(scaleWidth, scaleHeight);
Bitmap resizedBitmap = Bitmap.createBitmap(bm, 0, 0,Width, Height, matrix, true);
BitmapDrawable bmd = new BitmapDrawable(resizedBitmap);

【参考方案5】：

bm = Bitmap.createScaledBitmap(bitmapSource, width, height, true);

:)

【参考方案6】：

//照片为位图图片

Bitmap btm00 = Utils.getResizedBitmap(photo, 200, 200);

 setimage.setImageBitmap(btm00);

  And in Utils class :

public static Bitmap getResizedBitmap(Bitmap bm, int newHeight, int newWidth) 
    int width = bm.getWidth();
    int height = bm.getHeight();
    float scaleWidth = ((float) newWidth) / width;
    float scaleHeight = ((float) newHeight) / height;
    Matrix matrix = new Matrix();
    // RESIZE THE BIT MAP
    matrix.postScale(scaleWidth, scaleHeight);
    // RECREATE THE NEW BITMAP
    Bitmap resizedBitmap = Bitmap.createBitmap(bm, 0, 0, width, height,
            matrix, false);
    return resizedBitmap;

【参考方案7】：

BitmapFactory.Options options=new BitmapFactory.Options();
options.inSampleSize=2; //try to decrease decoded image 
Bitmap bitmap=BitmapFactory.decodeStream(is, null, options); 
bitmap.compress(Bitmap.CompressFormat.JPEG, 70, fos); //compressed bitmap to file 

【参考方案8】：

以下是通过保持相同的纵横比来调整位图大小的功能。在这里，我还写了一篇关于该主题的详细博客文章来解释这种方法。 Resize a Bitmap by Keeping the Same Aspect Ratio.

   public static Bitmap resizeBitmap(Bitmap source, int maxLength) 
       try 
           if (source.getHeight() >= source.getWidth()) 
               int targetHeight = maxLength;
               if (source.getHeight() <= targetHeight)  // if image already smaller than the required height
                   return source;
               

               double aspectRatio = (double) source.getWidth() / (double) source.getHeight();
               int targetWidth = (int) (targetHeight * aspectRatio);

               Bitmap result = Bitmap.createScaledBitmap(source, targetWidth, targetHeight, false);
               if (result != source) 
               
               return result;
            else 
               int targetWidth = maxLength;

               if (source.getWidth() <= targetWidth)  // if image already smaller than the required height
                   return source;
               

               double aspectRatio = ((double) source.getHeight()) / ((double) source.getWidth());
               int targetHeight = (int) (targetWidth * aspectRatio);

               Bitmap result = Bitmap.createScaledBitmap(source, targetWidth, targetHeight, false);
               if (result != source) 
               
               return result;

           
       
       catch (Exception e)
       
           return source;
       
   

【参考方案9】：

resized = Bitmap.createScaledBitmap(yourImageBitmap,(int)(yourImageBitmap.getWidth()*0.9), (int)(yourBitmap.getHeight()*0.9), true);

【参考方案10】：

BitmapFactory.Options options=new BitmapFactory.Options();
            options.inSampleSize = 10;
            FixBitmap = BitmapFactory.decodeFile(ImagePath, options);
            //FixBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.gv);

           byteArrayOutputStream = new ByteArrayOutputStream();
           FixBitmap.compress(Bitmap.CompressFormat.JPEG, 80, byteArrayOutputStream); //compress to 50% of original image quality
           byteArray = byteArrayOutputStream.toByteArray();

           ConvertImage = Base64.encodeToString(byteArray, Base64.DEFAULT);