對於在專案中，經常對圖片進行處理，來滿足不同功能需要，整理了部分常見需求程式碼，分享一下，後續不斷更新中

bitmap轉位元組陣列

public static byte[] bitmap2Bytes(final Bitmap bitmap, final CompressFormat format) {
        if (bitmap == null) return null;
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        bitmap.compress(format, 100, baos);
        return
 
 baos.toByteArray();
}

位元組陣列轉成bitmap

public static Bitmap bytes2Bitmap(final byte[] bytes) {
        return (bytes == null || bytes.length == 0)
                ? null
                : BitmapFactory.decodeByteArray(bytes, 0, bytes.length);
}

drawable轉成bitmap

public static Bitmap drawable2Bitmap(final Drawable drawable) {
        if (drawable instanceof BitmapDrawable) {
            BitmapDrawable bitmapDrawable = (BitmapDrawable) drawable;
 

            if (bitmapDrawable.getBitmap() != null) {
                return bitmapDrawable.getBitmap();
            }
        }
        Bitmap bitmap;
        if (drawable.getIntrinsicWidth() <= 0 || drawable.getIntrinsicHeight() <= 0) {
            bitmap = Bitmap.createBitmap(1, 1,
                    drawable.getOpacity
 
() != PixelFormat.OPAQUE
                            ? Bitmap.Config.ARGB_8888
                            : Bitmap.Config.RGB_565);
        } else {
            bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(),
                    drawable.getIntrinsicHeight(),
                    drawable.getOpacity() != PixelFormat.OPAQUE
                            ? Bitmap.Config.ARGB_8888
                            : Bitmap.Config.RGB_565);
        }
        Canvas canvas = new Canvas(bitmap);
        drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
        drawable.draw(canvas);
        return bitmap;
}

bitmap轉成Drawable

public static Drawable bitmap2Drawable(final Bitmap bitmap) {
        return bitmap == null ? null : new BitmapDrawable(Utils.getApp().getResources(), bitmap);
}

drawable轉位元組陣列

public static byte[] drawable2Bytes(final Drawable drawable, final CompressFormat format) {
        return drawable == null ? null : bitmap2Bytes(drawable2Bitmap(drawable), format);
}

位元組陣列轉 drawable

public static Drawable bytes2Drawable(final byte[] bytes) {
        return bitmap2Drawable(bytes2Bitmap(bytes));
}

view轉bitmap

public static Bitmap view2Bitmap(final View view) {
        if (view == null) return null;
        Bitmap ret = Bitmap.createBitmap(view.getWidth(),
                view.getHeight(),
                Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(ret);
        Drawable bgDrawable = view.getBackground();
        if (bgDrawable != null) {
            bgDrawable.draw(canvas);
        } else {
            canvas.drawColor(Color.WHITE);
        }
        view.draw(canvas);
        return ret;
}

新增文字水印

public static Bitmap addTextWatermark(final Bitmap src,
       final String content,final float textSize,@ColorInt final int color,final float x,final float y,final boolean recycle) {
        if (isEmptyBitmap(src) || content == null) return null;
        Bitmap ret = src.copy(src.getConfig(), true);
        Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
        Canvas canvas = new Canvas(ret);
        paint.setColor(color);
        paint.setTextSize(textSize);
        Rect bounds = new Rect();
        paint.getTextBounds(content, 0, content.length(), bounds);
        canvas.drawText(content, x, y + textSize, paint);
        if (recycle && !src.isRecycled()) src.recycle();
        return ret;
}

新增圖片水印

public static Bitmap addImageWatermark(final Bitmap src,
                                           final Bitmap watermark,
                                           final int x,
                                           final int y,
                                           final int alpha,
                                           final boolean recycle) {
        if (isEmptyBitmap(src)) return null;
        Bitmap ret = src.copy(src.getConfig(), true);
        if (!isEmptyBitmap(watermark)) {
            Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
            Canvas canvas = new Canvas(ret);
            paint.setAlpha(alpha);
            canvas.drawBitmap(watermark, x, y, paint);
        }
        if (recycle && !src.isRecycled()) src.recycle();
        return ret;
 }

透明bitmap

public static Bitmap toAlpha(final Bitmap src, final Boolean recycle) {
        if (isEmptyBitmap(src)) return null;
        Bitmap ret = src.extractAlpha();
        if (recycle && !src.isRecycled()) src.recycle();
        return ret;
}

灰色bitmap

public static Bitmap toGray(final Bitmap src, final boolean recycle) {
        if (isEmptyBitmap(src)) return null;
        Bitmap ret = Bitmap.createBitmap(src.getWidth(), src.getHeight(), src.getConfig());
        Canvas canvas = new Canvas(ret);
        Paint paint = new Paint();
        ColorMatrix colorMatrix = new ColorMatrix();
        colorMatrix.setSaturation(0);
        ColorMatrixColorFilter colorMatrixColorFilter = new ColorMatrixColorFilter(colorMatrix);
        paint.setColorFilter(colorMatrixColorFilter);
        canvas.drawBitmap(src, 0, 0, paint);
        if (recycle && !src.isRecycled()) src.recycle();
        return ret;
}

判斷是否是圖片

public static boolean isImage(final String filePath) {
        String path = filePath.toUpperCase();
        return path.endsWith(".PNG") || path.endsWith(".JPG")
                || path.endsWith(".JPEG") || path.endsWith(".BMP")
                || path.endsWith(".GIF") || path.endsWith(".WEBP");
}