安卓压缩图像小尺寸和良好的质量从相机的意图

Question

在我的应用程序中，用户可以根据相机意图拍照，然后我将此图像保存为全尺寸图像而不是缩略图。然后我想做的是使用这个保存的图像来压缩它并将其发送到服务器。

相机拍摄的图像大小约为7-8 MB，分辨率为5664x4248。

要求是实现相同大小和质量的whatsapp图像，这是40-80KB

我尝试了不同的解决方案，但无法达到同样好的质量和尺寸。

为此，我使用了id.zelory:compressor:2.1.1库

有什么想法吗？

在这里，我在保存图像后调用此方法来调整其大小

private File customCompressImage (File imgFile) {
String destinationDirectoryPath=  Environment.getExternalStorageDirectory().getPath() + "/Pictures/";
try {
return new CustomCompressor(context)
.setMaxWidth(612)
.setMaxHeight(816)
.setQuality(80)
.setCompressFormat(Bitmap.CompressFormat.JPEG)
.setDestinationDirectoryPath(destinationDirectoryPath)
.compressToFile(imgFile);
} catch (IOException e) {
e.printStackTrace();
}
return null;
}

压缩图像

static File compressImage(File imageFile, int reqWidth, int reqHeight, Bitmap.CompressFormat compressFormat, int quality, String destinationPath) throws IOException {
FileOutputStream fileOutputStream = null;
File file = new File(destinationPath).getParentFile();
if (!file.exists()) {
file.mkdirs();
}
try {
fileOutputStream = new FileOutputStream(destinationPath);
// write the compressed bitmap at the destination specified by destinationPath.
decodeSampledBitmapFromFile(imageFile, reqWidth, reqHeight).compress(compressFormat, quality, fileOutputStream);
} finally {
if (fileOutputStream != null) {
fileOutputStream.flush();
fileOutputStream.close();
}
}
return new File(destinationPath);
}

static Bitmap decodeSampledBitmapFromFile(File imageFile, int reqWidth, int reqHeight) throws IOException {
// First decode with inJustDecodeBounds=true to check dimensions
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(imageFile.getAbsolutePath(), options);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
Bitmap scaledBitmap = BitmapFactory.decodeFile(imageFile.getAbsolutePath(), options);
//check the rotation of the image and display it properly
ExifInterface exif;
exif = new ExifInterface(imageFile.getAbsolutePath());
int orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, 0);
Matrix matrix = new Matrix();
if (orientation == 6) {
matrix.postRotate(90);
} else if (orientation == 3) {
matrix.postRotate(180);
} else if (orientation == 8) {
matrix.postRotate(270);
}
scaledBitmap = Bitmap.createBitmap(scaledBitmap, 0, 0, scaledBitmap.getWidth(), scaledBitmap.getHeight(), matrix, true);
return scaledBitmap;
}

private static int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) {
// Raw height and width of image
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
final int halfHeight = height / 2;
final int halfWidth = width / 2;
// Calculate the largest inSampleSize value that is a power of 2 and keeps both
// height and width larger than the requested height and width.
while ((halfHeight / inSampleSize) >= reqHeight && (halfWidth / inSampleSize) >= reqWidth) {
inSampleSize *= 2;
}
}
return inSampleSize;
}

我试着通过不同的最大宽度、高度和质量，但我从未达到小尺寸和高质量的

Answer 1

您可以尝试这段代码。

public static Bitmap getCompressed( Bitmap imageBitmap) {
ByteArrayOutputStream bytes = new ByteArrayOutputStream();
imageBitmap.compress(Bitmap.CompressFormat.JPEG, 100, bytes);
return imageBitmap;
}

//100是质量，根据您的需要更改

Answer 2

@最终用户不应该是这样的吗(这至少是我从阅读文档中得到的(：

public static Bitmap getCompressed(Bitmap imageBitmap) {
ByteArrayOutputStream out = new ByteArrayOutputStream();
if (!imageBitmap.compress(Bitmap.CompressFormat.JPEG, 100, out))
throw new IllegalStateException("Unable to compress image");
ByteArrayInputStream in = new ByteArrayInputStream(out.toByteArray());
return BitmapFactory.decodeStream(in);
}