Question

我正在尝试创建一个应用程序，我需要在SQLite数据库中存储和检索图像。我得到的程序使用BLOB将图像存储为字节数组，我也能够检索字节数组，但在将数组解码为位图时，BitmapFactory返回null。请帮忙。这是我用来解码数组的代码。

Cursor c=db.rawQuery("SELECT * FROM student WHERE name='"+"1"+"'", null);
                if(c.moveToFirst())
                {
                    byte[] outImage=c.getBlob(1);
                    Log.d("The out image is", String.valueOf(outImage));
                    Bitmap bitmap = BitmapFactory.decodeByteArray(outImage , 0, outImage .length);
                    iv.setImageBitmap(bitmap);
                }

这就是我在数据库中插入byte []的方法：

if(requestCode==CAMERA_REQUEST && resultCode==RESULT_OK){

                Bitmap yourImage = (Bitmap) data.getExtras().get("data");
                // convert bitmap to byte
                ByteArrayOutputStream stream = new ByteArrayOutputStream();
                yourImage.compress(Bitmap.CompressFormat.JPEG, 100, stream);
                byte[] imageInByte = stream.toByteArray();
                Log.e("output before conversion", imageInByte.toString());
                // Inserting Contacts
                Log.d("Insert: ", "Inserting ..");
                db.execSQL("INSERT INTO student VALUES('"+"1"+"','"+imageInByte+"');");
                Log.d("Success: ", "Image Saved");       
        }

logcat读取类似这样的内容

12-24 23:39:49.777: E/output before conversion(22523): [B@13fd7069
12-24 23:39:49.778: D/Insert:(22523): Inserting ..
12-24 23:39:49.840: D/Success:(22523): Image Saved
12-24 23:39:51.579: D/The out image is(22523): [B@155f0aee
12-24 23:39:51.580: D/skia(22523): --- SkImageDecoder::Factory returned null

Answer 1

解码器返回null，因为您没有传递有效数据。首先将blob转换为byteArray

Blob blob = c.getBlob(1);
int blobLength = (int) blob.length();  
byte[] outImage = blob.getBytes(1, blobLength);
Log.d("The out image is", String.valueOf(outImage));
                Bitmap bitmap = BitmapFactory.decodeByteArray(outImage , 0, outImage .length);
                iv.setImageBitmap(bitmap);

blob.free();

BitmapFactory返回null

1 个答案: