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digitalmars.D.announce - pure D JPEG decoder, with progressive JPEG support, public domain

reply ketmar <ketmar ketmar.no-ip.org> writes:
finally, the thing you all waited for years is here! pure D 
no-frills JPEG decoder with progressive JPEG support! Public 
Domain! one file! no Phobos or other external dependecies! it 
even has some DDoc! grab it[1] now while it's hot!

[1] http://repo.or.cz/iv.d.git/blob_plain/HEAD:/jpegd.d
Jun 17 2016
next sibling parent reply John Colvin <john.loughran.colvin gmail.com> writes:
On Friday, 17 June 2016 at 13:05:47 UTC, ketmar wrote:

 finally, the thing you all waited for years is here! pure D 
 no-frills JPEG decoder with progressive JPEG support! Public 
 Domain! one file! no Phobos or other external dependecies! it 
 even has some DDoc! grab it[1] now while it's hot!

 [1] http://repo.or.cz/iv.d.git/blob_plain/HEAD:/jpegd.d


awesome.

Without wanting to start a huge thing about this, see 
http://linuxmafia.com/faq/Licensing_and_Law/public-domain.html 
and http://www.rosenlaw.com/lj16.htm and please at least add an 
optional licencing under a traditional permissive open-source 
license (boost would be nice, who knows, maybe phobos should have 
jpeg support?).
Jun 17 2016
next sibling parent reply Kagamin <spam here.lot> writes:
On Friday, 17 June 2016 at 13:35:58 UTC, John Colvin wrote:

 Without wanting to start a huge thing about this, see 
 http://linuxmafia.com/faq/Licensing_and_Law/public-domain.html 
 and http://www.rosenlaw.com/lj16.htm and please at least add an 
 optional licencing under a traditional permissive open-source 
 license (boost would be nice, who knows, maybe phobos should 
 have jpeg support?).


Uh oh, a license is revokable? What happens when boost license is 
revoked?
Jun 17 2016
parent ag0aep6g <anonymous example.com> writes:
On 06/17/2016 04:08 PM, Kagamin wrote:

 Uh oh, a license is revokable? What happens when boost license is revoked?


No, it's not, but you can publish stuff under multiple licenses at the 
same time.
Jun 17 2016
prev sibling next sibling parent ketmar <ketmar ketmar.no-ip.org> writes:
On Friday, 17 June 2016 at 13:35:58 UTC, John Colvin wrote:

 Without wanting to start a huge thing about this, see 
 http://linuxmafia.com/faq/Licensing_and_Law/public-domain.html 
 and http://www.rosenlaw.com/lj16.htm and please at least add an 
 optional licencing under a traditional permissive open-source 
 license (boost would be nice, who knows, maybe phobos should 
 have jpeg support?).


ah, i know about PD caveats. but the original source was PD, so i 
don't feel like adding any other license on top of it will be 
good. not that it is legally impossible, i just want to keep it 
as the original author intended. after all, anybody can just fork 
it and add any license he wants. it is unlikely that the thing 
will get extensive upgrades anyway. ;-)
Jun 17 2016
prev sibling next sibling parent reply Rory McGuire via Digitalmars-d-announce writes:
On Fri, Jun 17, 2016 at 3:35 PM, John Colvin via Digitalmars-d-announce <
digitalmars-d-announce puremagic.com> wrote:


 On Friday, 17 June 2016 at 13:05:47 UTC, ketmar wrote:


 finally, the thing you all waited for years is here! pure D no-frills
 JPEG decoder with progressive JPEG support! Public Domain! one file! no
 Phobos or other external dependecies! it even has some DDoc! grab it[1] now
 while it's hot!

 [1] http://repo.or.cz/iv.d.git/blob_plain/HEAD:/jpegd.d


 awesome.

 Without wanting to start a huge thing about this, see
 http://linuxmafia.com/faq/Licensing_and_Law/public-domain.html and
 http://www.rosenlaw.com/lj16.htm and please at least add an optional
 licencing under a traditional permissive open-source license (boost would
 be nice, who knows, maybe phobos should have jpeg support?).


Thanks for that info. I don't think it would help if ketmar made it MIT /
Boost licensed or any other, if the original authors relatives chose to
dispute the license it the fact that the code is based on the PD code would
make it hard to protect.

I think that source code under PD might get exception to the laws in those
articles because of the way PD is used globally and what its intent is, and
what our common understanding of it is. However that would probably go to
court to settle.
Jun 17 2016
parent reply ketmar <ketmar ketmar.no-ip.org> writes:
On Friday, 17 June 2016 at 14:28:52 UTC, Rory McGuire wrote:

 Thanks for that info. I don't think it would help if ketmar 
 made it MIT / Boost licensed or any other, if the original 
 authors relatives chose to dispute the license it the fact that 
 the code is based on the PD code would make it hard to protect.


ah, just fork it and slap Boost license on top! i myself have no 
objections, and i doubt that the original author will object too.
Jun 17 2016
parent ketmar <ketmar ketmar.no-ip.org> writes:
On Friday, 17 June 2016 at 14:33:41 UTC, ketmar wrote:

 ah, just fork it and slap Boost license on top! i myself have 
 no objections, and i doubt that the original author will object 
 too.


p.s. i'm pretty sure that somebody *will* fork it soon to get it 
to code.dlang.org. i won't do that myself, but again, i have no 
objections.
Jun 17 2016
prev sibling parent reply ketmar <ketmar ketmar.no-ip.org> writes:
On Friday, 17 June 2016 at 13:35:58 UTC, John Colvin wrote:

 On Friday, 17 June 2016 at 13:05:47 UTC, ketmar wrote:

 finally, the thing you all waited for years is here! pure D 
 no-frills JPEG decoder with progressive JPEG support! Public 
 Domain! one file! no Phobos or other external dependecies! it 
 even has some DDoc! grab it[1] now while it's hot!

 [1] http://repo.or.cz/iv.d.git/blob_plain/HEAD:/jpegd.d


 awesome.

 Without wanting to start a huge thing about this, see 
 http://linuxmafia.com/faq/Licensing_and_Law/public-domain.html 
 and http://www.rosenlaw.com/lj16.htm and please at least add an 
 optional licencing under a traditional permissive open-source 
 license (boost would be nice, who knows, maybe phobos should 
 have jpeg support?).


i put it under unlicense[1], as some other works of the same 
author is using it, and it is basically the same PD.

[1] http://unlicense.org/
Jun 17 2016
parent reply Xinok <xinok live.com> writes:
On Friday, 17 June 2016 at 22:15:47 UTC, ketmar wrote:

 i put it under unlicense[1], as some other works of the same 
 author is using it, and it is basically the same PD.

 [1] http://unlicense.org/


Unfortunately, using unlicense is just as problematic as using 
public domain:

https://programmers.stackexchange.com/questions/147111/what-is-wrong-with-the-unlicense

The next best thing is the CC0 license (Creative Commons Zero) 
which is better written than unlicense but it's currently not 
recommended for software / source code.

http://copyfree.org/content/standard/licenses/cc0/license.txt

After that, the most-open licenses with good legal standing would 
be Boost and MIT but then you run into the same issues again with 
incompatible licenses.

I don't have any recommendations but I thought it was worth 
pointing out that unlicense isn't the solution here.
Jun 17 2016
parent ketmar <ketmar ketmar.no-ip.org> writes:
On Friday, 17 June 2016 at 23:17:56 UTC, Xinok wrote:

 On Friday, 17 June 2016 at 22:15:47 UTC, ketmar wrote:

 i put it under unlicense[1], as some other works of the same 
 author is using it, and it is basically the same PD.

 [1] http://unlicense.org/


 Unfortunately, using unlicense is just as problematic as using 
 public domain:

 https://programmers.stackexchange.com/questions/147111/what-is-wrong-with-the-unlicense


alas, that is all i can do without breaking the "spirit" of the 
original terms. i'm ok with it, and people still can fork the 
code and relicense in under Boost/MIT.
Jun 17 2016
prev sibling next sibling parent reply Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
On 06/17/2016 09:05 AM, ketmar wrote:

 finally, the thing you all waited for years is here! pure D no-frills
 JPEG decoder with progressive JPEG support! Public Domain! one file! no
 Phobos or other external dependecies! it even has some DDoc! grab it[1]
 now while it's hot!

 [1] http://repo.or.cz/iv.d.git/blob_plain/HEAD:/jpegd.d


Nice, thanks for this work. I see it has 3213 lines. I take it the 
source is https://github.com/richgel999/jpeg-compressor. How many lines 
from there are reflected in the D code? -- Andrei
Jun 17 2016
parent reply ketmar <ketmar ketmar.no-ip.org> writes:
On Friday, 17 June 2016 at 13:51:29 UTC, Andrei Alexandrescu 
wrote:

 Nice, thanks for this work. I see it has 3213 lines. I take it 
 the source is https://github.com/richgel999/jpeg-compressor. 
 How many lines from there are reflected in the D code? -- Andrei


it's a complete port of jpegd.h+jpegd.cpp (so, no encoder). it is 
almost 1:1 to c++ code, including fancy templated row/col 
decoders and 4x4 matrix mini-class. mostly sed work, and after i 
made it to compile (and fixed silly bug in CLAMP that i 
introduced) it "just works". i replaced stream reader class with 
delegate (we have such a great delegates in D, so let's use 'em! 
;-), but otherwise the code is unmodified.

ah, i also put `.ptr` to array access to skip bounds checking -- 
i love to build my code with bounds checking on, and i don't feel 
that i need it in this decoder -- it should be fairly well-tested.

so you may assume that all of the lines there are came from c++ 
(sans some curly brackets).

of course, one can do much better work by writing "idiomatic" D 
code, i guess, but that would be much greater work -- not a 
"port", but "rewrite".
Jun 17 2016
parent reply Observer <here inter.net> writes:
On Friday, 17 June 2016 at 14:20:14 UTC, ketmar wrote:

 ah, i also put `.ptr` to array access to skip bounds checking 
 -- i love to build my code with bounds checking on, and i don't 
 feel that i need it in this decoder -- it should be fairly 
 well-tested.


This statement stands out as a problem.  There are lots of 
security
notices out there that refer to media-decoding problems.  
Remember,
in the context of image decoding, you're often handling untrusted
data from external sources.  The security notices often talk about
"carefully crafted" files; here's just one simple example:

     http://www.videolan.org/security/sa0702.html

Here are a couple more, regarding the infamous Adobe Flashplayer:

     https://hackerone.com/reports/30567
     https://hackerone.com/reports/36279

Not convinced?  Let's not stop there; let's look specifically at
what has happened with JPEG in the past, such as:

     http://download.oracle.com/sunalerts/1000310.1.html
     http://www.theregister.co.uk/2004/09/24/jpeg_exploit_toolkit/

You need to think not just about your own code, but also about the
overall environment in which it will operate.
Jun 18 2016
next sibling parent ketmar <ketmar ketmar.no-ip.org> writes:
On Saturday, 18 June 2016 at 19:52:20 UTC, Observer wrote:

 Not convinced?


no. i believe that it's all strongly overrated. don't run 
software with full access to your system, don't feed it with 
untrusted data, use sandboxes and such, etc. this is the way to 
go, not adding endless checks for all possible corner cases.

still, anyone is free to undo that: just replace all `\.ptr\b` 
with empty string -- and voila! all the bounds checking (and mind 
you, there is little, as many arrays are just malloc'ed anyway) 
is back. it's way easier to do than to put `.ptr` into vanilla 
code.

for my use cases `.ptr` access is ok: i prefer to leave bounds 
checking on for all builds, and manually escape it in the code 
when i feel that it is necessary.

in other words: i believe that validating data and 
loading/processing data should be separated. first validate all 
your jpegs with some tool, then use loaders to actually load and 
process 'em.
Jun 18 2016
prev sibling parent Adam D. Ruppe <destructionator gmail.com> writes:
On Saturday, 18 June 2016 at 19:52:20 UTC, Observer wrote:

 in the context of image decoding, you're often handling 
 untrusted data from external sources


Not always though. The main case I'd use a little single-file 
thing is for files that I created and packaged with the 
application myself, but wanted to be small for distribution. If I 
wanted my program to do something naughty, I wrote it, I'd just 
make it do something naughty!
Jun 18 2016
prev sibling parent Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
On 06/17/2016 09:05 AM, ketmar wrote:

 finally, the thing you all waited for years is here! pure D no-frills
 JPEG decoder with progressive JPEG support! Public Domain! one file! no
 Phobos or other external dependecies! it even has some DDoc! grab it[1]
 now while it's hot!

 [1] http://repo.or.cz/iv.d.git/blob_plain/HEAD:/jpegd.d


https://www.reddit.com/r/programming/comments/4oj7ja/public_domain_jpeg_decoder_with_progressive/

Andrei
Jun 17 2016