qpdf 命令

常用示例

说明

qpdf is a command-line tool for structural, content-preserving transformations of PDF files. Unlike tools that rasterize or re-render, qpdf manipulates PDF structure directly. Primary uses include encryption management (decrypting, encrypting, changing passwords), linearization (optimizing for web delivery), and page manipulation (merging, splitting, reordering). Page specification uses flexible syntax: ranges (1-10), specific pages (1,3,5), reverse (z-1), and rotation (1-5:90). Multiple files can contribute pages using --pages with file:range pairs. The --check option validates PDF structure without modifying, useful for identifying damaged files. JSON output exposes internal structure for analysis or custom processing. QDF mode produces "normalized" PDFs that can be edited with text editors, enabling debugging and manual fixes. Stream decompression reveals human-readable content. Linearization reorganizes PDFs for efficient byte-serving over HTTP, enabling page-at-a-time loading without downloading entire files.

参数

--decrypt

Remove encryption.

--linearize

Optimize for web viewing.

--encrypt _user_ _owner_ _bits_ --

Add encryption (bits: 40, 128, or 256).

--pages _spec_

Page selection specification.

--collate=_n_

Collate pages from multiple files rather than concatenating.

--rotate _+|-__angle_:_pages_

Rotate pages.

--empty

Use empty PDF as input base.

--replace-input

Overwrite input file with output instead of writing to a separate file.

--check

Check PDF structure.

--show-encryption

Display encryption details.

--password _PASS_

Input file password.

--compress-streams=_y|n_

Compress/decompress streams.

--object-streams=_mode_

Control object streams: preserve, disable, or generate.

--decode-level _LEVEL_

Stream decoding: none, generalized, specialized, all.

--normalize-content=_y|n_

Normalize content streams.

--split-pages=_n_

Split into n-page files.

--overlay _file_

Overlay pages from file.

--underlay _file_

Underlay pages from file.

--flatten-rotation

Make rotation permanent.

--flatten-annotations=_parameter_

Flatten annotation appearances.

--coalesce-contents

Combine multiple content streams per page into one.

--optimize-images

Use efficient compression for images.

--remove-unreferenced-resources=_auto|yes|no_

Remove unused resources from page dictionaries.

--json

Output PDF structure as JSON.