Android拍照並在保存在SD卡上之前調整大小

Question

我希望我的代碼在保存前調整圖像大小，但在Google上找不到它。 你能幫我嗎？

這是代碼（從Android電子文檔）：

private void galleryAddPic() { 
    Intent mediaScanIntent = new Intent("android.intent.action.MEDIA_SCANNER_SCAN_FILE"); 
    File f = new File(mCurrentPhotoPath); 

    picturePathForUpload = mCurrentPhotoPath; 

    Uri contentUri = Uri.fromFile(f); 
    mediaScanIntent.setData(contentUri); 
    this.sendBroadcast(mediaScanIntent); 
} 

在那之後，我必須把它上傳到服務器。

非常感謝。

Answer 1

您可以保存位圖圖像下面的代碼

Bitmap photo = (Bitmap) "your Bitmap image"; 
photo = Bitmap.createScaledBitmap(photo, 100, 100, false); 
ByteArrayOutputStream bytes = new ByteArrayOutputStream(); 
photo.compress(Bitmap.CompressFormat.JPEG, 40, bytes); 

File f = new File(Environment.getExternalStorageDirectory() 
     + File.separator + "Imagename.jpg"); 
f.createNewFile(); 
FileOutputStream fo = new FileOutputStream(f); 
fo.write(bytes.toByteArray()); 
fo.close(); 

Answer 2

首先轉換您的圖像以位圖，則使用此代碼：

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

Answer 3

See this將有助於充分。一般來說，如果你是通過相機中使用的意圖拍攝的圖像，你會得到圖像的uri的結果你讀它的規模縮小圖像，並將其存儲在同一個地方

Answer 4

如果你想捕捉一個完整大小的圖像，那麼你別無選擇，只能將其保存到SD購物車，然後更改圖像的大小。

但是，如果縮略圖圖像足夠，則不需要將其保存到SD卡，並且可以從返回的意圖的附加內容中提取它。

你可以看一下這個指南我寫的攝像頭Activity採取使用構建圖像兩種方法：

Guide: Android: Use Camera Activity for Thumbnail and Full Size Image

Answer 5

閱讀其他的答案，並沒有找到正是我想要的以後，這裏是我的方法獲取適當縮放的位圖。這是Prabu答案的改編。

它可以確保您的圖片是在不變形的照片尺寸的方式縮放：

public saveScaledPhotoToFile() { 
    //Convert your photo to a bitmap 
    Bitmap photoBm = (Bitmap) "your Bitmap image"; 
    //get its orginal dimensions 
    int bmOriginalWidth = photoBm.getWidth(); 
    int bmOriginalHeight = photoBm.getHeight(); 
    double originalWidthToHeightRatio = 1.0 * bmOriginalWidth/bmOriginalHeight; 
    double originalHeightToWidthRatio = 1.0 * bmOriginalHeight/bmOriginalWidth; 
    //choose a maximum height 
    int maxHeight = 1024; 
    //choose a max width 
    int maxWidth = 1024; 
    //call the method to get the scaled bitmap 
    photoBm = getScaledBitmap(photoBm, bmOriginalWidth, bmOriginalHeight, 
      originalWidthToHeightRatio, originalHeightToWidthRatio, 
      maxHeight, maxWidth); 

    /**********THE REST OF THIS IS FROM Prabu's answer*******/ 
    //create a byte array output stream to hold the photo's bytes 
    ByteArrayOutputStream bytes = new ByteArrayOutputStream(); 
    //compress the photo's bytes into the byte array output stream 
    photoBm.compress(Bitmap.CompressFormat.JPEG, 40, bytes); 

    //construct a File object to save the scaled file to 
    File f = new File(Environment.getExternalStorageDirectory() 
      + File.separator + "Imagename.jpg"); 
    //create the file 
    f.createNewFile(); 

    //create an FileOutputStream on the created file 
    FileOutputStream fo = new FileOutputStream(f); 
    //write the photo's bytes to the file 
    fo.write(bytes.toByteArray()); 

    //finish by closing the FileOutputStream 
    fo.close(); 
} 

private static Bitmap getScaledBitmap(Bitmap bm, int bmOriginalWidth, int bmOriginalHeight, double originalWidthToHeightRatio, double originalHeightToWidthRatio, int maxHeight, int maxWidth) { 
    if(bmOriginalWidth > maxWidth || bmOriginalHeight > maxHeight) { 
     Log.v(TAG, format("RESIZING bitmap FROM %sx%s ", bmOriginalWidth, bmOriginalHeight)); 

     if(bmOriginalWidth > bmOriginalHeight) { 
      bm = scaleDeminsFromWidth(bm, maxWidth, bmOriginalHeight, originalHeightToWidthRatio); 
     } else { 
      bm = scaleDeminsFromHeight(bm, maxHeight, bmOriginalHeight, originalWidthToHeightRatio); 
     } 

     Log.v(TAG, format("RESIZED bitmap TO %sx%s ", bm.getWidth(), bm.getHeight())); 
    } 
    return bm; 
} 

private static Bitmap scaleDeminsFromHeight(Bitmap bm, int maxHeight, int bmOriginalHeight, double originalWidthToHeightRatio) { 
    int newHeight = (int) Math.min(maxHeight, bmOriginalHeight * .55); 
    int newWidth = (int) (newHeight * originalWidthToHeightRatio); 
    bm = Bitmap.createScaledBitmap(bm, newWidth, newHeight, true); 
    return bm; 
} 

private static Bitmap scaleDeminsFromWidth(Bitmap bm, int maxWidth, int bmOriginalWidth, double originalHeightToWidthRatio) { 
    //scale the width 
    int newWidth = (int) Math.min(maxWidth, bmOriginalWidth * .75); 
    int newHeight = (int) (newWidth * originalHeightToWidthRatio); 
    bm = Bitmap.createScaledBitmap(bm, newWidth, newHeight, true); 
    return bm; 
} 

這裏有一個對應的鏈接到我的GitHub的要點是：https://gist.github.com/Lwdthe1/2d1cd0a12f30c18db698

Answer 6

BitmapFactory.Options optionsSignature = new BitmapFactory.Options(); 
final Bitmap bitmapSignature = BitmapFactory.decodeFile(
fileUriSignature.getPath(), optionsSignature); 
Bitmap resizedSignature = Bitmap.createScaledBitmap(
       bitmapSignature, 256, 128, true); 
signature.setImageBitmap(resizedSignature);