Bộ công cụ web xử lý ảnh và PDF hoàn toàn trên trình duyệt, không tải file lên máy chủ

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Nhiều trang công cụ trực tuyến miễn phí tải file nhạy cảm như ảnh hộ chiếu hay hợp đồng PDF lên máy chủ từ xa, gây rủi ro bảo mật đáng kể. Một số công cụ che thông tin PDF chỉ phủ hình chữ nhật đen lên văn bản mà không xóa dữ liệu bên dưới, khiến người khác vẫn có thể sao chép thông tin ẩn. Nhóm phát triển OnDevice Desk đề xuất bộ 4 công cụ miễn phí chạy hoàn toàn cục bộ bằng Web Workers và OffscreenCanvas, dữ liệu không rời khỏi máy người dùng. Bài viết cũng mô tả kỹ thuật tạo ảnh 300 DPI đáp ứng yêu cầu của các cổng nộp hồ sơ hộ chiếu, thị thực và CCCD, cùng thuật toán tạo viền sticker hiệu quả.

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