[TAG] .SWF files (Flash)

[Benjamin A. Okopnik]

On Thu, Feb 09, 2006 at 03:29:05PM -0800, Kapil Hari Paranjape wrote:
> Hello,
> 
> This may be OT as far as the discussion on "flash or not" is concerned,
> but here goes anyway.
> 
> I saw this a couple of times.
> 
> Here:
> 
> On Wed, 08 Feb 2006, Benjamin A. Okopnik wrote:
> > Oh, and - Flash produces excellent image quality in a file size that's
> > about half the size of a very poor JPG image, as well as auto-sizing
> > itself to whatever the viewer's screen size is. Just a minor side note.
> 
> And here:
> 
> On Thu, 09 Feb 2006, Mike Orr wrote:
> > On 2/8/06, shane <shane_collinge at yahoo.com> wrote:
> > > (2) SWF are insanely small file sizes with comparably, insanely
> > > high file quality that fit ANY screen res - something JPGs don't
> > > do.
> 
> and I'm a bit puzzled. Why would people want to put cartoons in a JPEG
> format? As I understand it JPEG is for photographs, not for drawings.

I've actually spent some time reading up on image formats in the past,
and have seen the 'this format is best for $FOOBAR, while that one is
best for $BLAH' arguments. As far as I'm concerned, in practice, they're
not real distinctions. That is, it is possible to make a 16 million
color PNG in a ~60kB-size file (and a 256x256 color in 678 (!) bytes),
but that appears to bear _no_ relation to processing actual, real-life
images, where I want the image to convey maximum information in a
minimum file size. In that latter case, except for a small number of
exceptions - and I'm sad to say that I have not determined the common
factor for those - JPGs come out smaller than PNGs, by an overwhelming
majority.

In the case of one of Shane's cartoons, it looks like this:

502thumbs.swf    20269
502thumbs.jpg    53862
502thumbs.png   138759

Note that both the JPG and the PNG have been compressed as much as
possible without losing image quality (via "jpegoptim" and "pngcrush",
respectively) and are each 800x335px in size; both show up rather jaggy
on my 1280x800 screen. The SWF, despite its much smaller filesize, shows
no visible artifacts when viewed at that resolution; bringing the two
images up to an equivalent display size nearly doubles the filesize.

> PNG is a reasonable format for drawings that need to be exported in
> bitmap format. For drawings that were made in vector format and will
> be subjected to arbitrary scaling there is SVG and Java...and also
> Flash. As far as I know the latter is an open format, though the
> software most commonly used to produce and view the content is not
> free.

Thank you for bringing that up: that's precisely the point that I made
to Saul (the one person who complained about Flash last month.) The
*creator* software from Macromedia has a restrictive license; the viewer
software does not appear to have anything nearly as restrictive, and the
format itself is, AFAIK, open.

> As I pointed out earlier, there *is* software that can be used
> to view flash that is free as in libre---in fact I viewed the HelpDex
> stuff using swfplayer.

There's also FOSS software that can be used to create it - which, as far
as I'm concerned, ties down both ends of this equation.

> The only reason for leaving out PNG in the past would have been that
> there were still some browser/OS combinations out there that did not
> support it. Does that problem still persist?

Not as far as I'm aware. That problem is way in the past, AFAIK.


* Ben Okopnik * Editor-in-Chief, Linux Gazette * http://linuxgazette.net *