JclCompression

Abbrevia

ZLib

TZipFile

Compression Formats

Zip, 7z, GZip, Tar, ....

Zip, Cab, tar, gzip

zlib

zip

Can vary compression

Yes: 0 (Store), 1,3,5,7,9

Do not know

none, fastest, default, max

Yes. Multiple options, not all supported.

Encryption

AES-256 for 7z,

AES-128, 256,  ZipCrypto for zip.

Do not know, pdf has chapter dedicated to Compression

No

No

Can handle multiple volumes.

Yes for Compression.

Probably for extraction, but I haven't worked out how to do it.

Yes (but have not tried it)

No - Single File

No

32-bit and 64-bit

Yes

Yes

Yes

Yes

Cross Platform

No. Appears not.

Win, OS X

Yes

Yes

Can handle files > 4GB

Yes.

Yes

?

Yes, but untested

Requirements

7z.dll required in path or app directory. Must match 32-bit or 64-bit.

\source in path

no external dependencies

no external dependencies

Documentation

Non-existent.

Pdf from original product

Delphi

Delphi Help

Sample Code

Covers basics well.

Yes, plenty

Yes

Yes. Full source code

Pros

Good functionality, including encryption.

Good compression ratios.

7z format stores dates as UTC- good for file transfrs

Compiles to EXE.

Good documentation.

* Compiles to EXE

* Cross platform

Comes with Delphi

Compiles into EXE

Cons

7z.dll required.

Not cross platform.

Lack of Documentation.

 

* No encryption

* Only core functionality:

- Works on buffers, strings, streams

- Not multiple files as a package

* Mediocre compression (~30% for text)

No encryption.

Bug unzipping zero length files. See QC99443. Claims fixed in XE3 and above.

 

 

Links

 

JclCompression

http://sourceforge.net/projects/jcl/

( the download link from http://www.delphi-jedi.org/ is an old version).

 

Abbrevia

http://sourceforge.net/projects/tpabbrevia/

http://tpabbrevia.sourceforge.net/

 

ZLib

Comes with Delphi.

 

TZipFile
Included with Delphi since XE?