Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

JPG Compression - The Bandwidth Saver

Hemos posted about 12 years ago | from the cutting-down-on-bandwidth-costs dept.

Graphics 316

Mr.Tweak writes "TweakTown has posted an article entitled "JPG Compression - The Bandwidth Saver". An article for webmasters and site owners showing how they can significantly reduce the amount of bandwidth they use by compressing JPG images, one of the most common formats for web images. If you own a website and don't yet have knowledge in the field of JPG compression, you should find this very interesting indeed - Save money on bandwidth and please viewers at the same time with quicker loading webpages. They also talk briefly at JPEG2000."

cancel ×
This is a preview of your comment

No Comment Title Entered

Anonymous Coward 1 minute ago

No Comment Entered


Yatta! (-1, Offtopic)

Anonymous Coward | about 12 years ago | (#3379787)

We are the wad of dough!
Who dong hide?

Things To Do Today (-1, Troll)

Anonymous Coward | about 12 years ago | (#3379822)

1. Eat an ass

2. Eat an Altoid

Where the FUCK are the KDE3 debs??? (-1, Offtopic)

Anonymous Coward | about 12 years ago | (#3379962)

Abdullah surreptitiously crawls over the open window from which the sounds of a pizza party on a non-school night are playing. He gets beneath the window, pulls the pin out of the grenade with his quivering lips, and rolls the pineapple over the window sill...

This will definitely get me the 72 virgins, he thinks, giggling to himself.

Parent is more on-topic than you think (1, Insightful)

Anonymous Coward | about 12 years ago | (#3379897)

Yatta! We are the wad of dough! Who dong hide?

Translation [mit.edu]: "All right! We are the world! We just go to bed."

These are lyrics from "Yatta!" by Happatai (the Japanese version of the Village People), as interpreted in "Irrational Exuberance" [verylowsodium.com], a popular Flash music video of the song.

Surprisingly, the parent is somewhat on-topic because Flash videos [animutation.com] use JPEG compression technology to save bandwidth.

More advice (4, Funny)

kindbud (90044) | about 12 years ago | (#3379791)

Computers can make problems requiring complex repetitive calculations a much less onerous task to solve. I highly recommend that people apply computers to difficult scientific questions.

Re:More advice (0)

fuckthetux (234672) | about 12 years ago | (#3379838)

Humans can make problems even without making calculations. I therefor highly recommend that computers apply humans to less difficlut questions

answer: drop the mirror!

Impeach George W. Bush @# +1 ; Patriotic @# (-1, Offtopic)

Anonymous Coward | about 12 years ago | (#3379944)

While you're probably sick of hearing about Donald Rumsfeld, it is crucial that you read this letter. I guess I should start by saying that I can't follow Rumsfeld's pretzel logic. I do, however, know that as soon as his forces slow scientific progress, they will have destroyed the basis for their own existence. The mere mention of that fact guarantees that this letter will never get published in any mass-circulation periodical that Rumsfeld has any control over. But that's inconsequential, because Rumsfeld's favorite scapegoats are the government, the economy, the environment, society, parents, teachers, and just about everything else, and everyone with half a brain understands that. Rumsfeld's lapdogs are an amalgamation of vitriolic carousers, sinful unbridled-types, and other filthy masters of deceit. To top that off, several things Rumsfeld has said have brought me to the boiling point. The statement of his that made the strongest impression on me, however, was something to the effect of how a plausible excuse is a satisfactory substitute for performance. Please don't misread my words here; there's something fishy about his demands. I myself think he's up to something, something nerdy and perhaps even sinister. Contrary to what Rumsfeld would have you believe, some of the facts I'm about to present may seem shocking. This they certainly are. However, he respects nothing, honors nothing, and values nothing beyond himself -- and Rumsfeld knows it. Because "photoreconnaissance" is a word that can be interpreted in many ways, we must make it clear that he thinks that we should avoid personal responsibility. Of course, thinking so doesn't make it so.

I'm sorry if I've gotten a little off track here, but the tone of Rumsfeld's scare tactics is eerily reminiscent of that of uneducated bullies of the late 1940s, in the sense that Rumsfeld wants to empty garbage pails full of the vilest slanders and defamations on the clean garments of honorable people. Why he wants that, I don't know, but that's what he wants. Some people have compared shallow, rotten half-wits to disdainful energumens. I would like to take the comparison one step further.

Astute observers have known for years that everything I've said so far is by way of introduction to the key point I want to make in this letter. My key point is that I, for one, can undoubtedly suggest how Rumsfeld ought to behave. Ultimately, however, the burden of acting with moral rectitude lies with Rumsfeld himself. Now that I think about it, I'm not a psychiatrist. Sometimes, though, I wish I were, so that I could better understand what makes people like him want to arouse inter-ethnic suspicion. Even so, Rumsfeld is doing everything in his power to make me fall prey to Rumsfeld's rhetoric and obfuscation. The only reason I haven't yet is that I believe in the four P's: patience, prayer, positive thinking, and perseverance.

I find that I am embarrassed. Embarrassed that some people don't realize that because of his obsession with interventionism, if Rumsfeld has spurred us to take advantage of a rare opportunity to justify condemnation, constructive criticism, and ridicule of him and his headlong whinges, then Rumsfeld may have accomplished a useful thing. There's a little-known truth that isn't readily acknowledged by jaundiced cowards: Rumsfeld doesn't use words for communication or for exchanging information. He uses them to disarm, to hypnotize, to mislead, and to deceive. I, hardheaded cynic that I am, would never take a job working for him. Given his disagreeable epithets, who would want to?

Rumsfeld doesn't have any principles, or if he does, he puts them aside whenever they're inconvenient. If the only way to reveal some shocking facts about his ideals is for me to suffer from stress, frustration, and defeat, then so be it. It would indubitably be worth it, because I am certain that if I asked the next person I meet if he would want Rumsfeld to treat anyone who doesn't agree with him to a torrent of vitriol and vilification, he would say no. Yet we all stand idly by while Rumsfeld claims that he is a martyr for freedom and a victim of favoritism. Paltry adulterers (like Rumsfeld) are not born -- they are excreted. However unsavory that metaphor may be, if Rumsfeld continues to play fast and loose with the truth, crime will escalate as schools deteriorate, corruption increases, and quality of life plummets. If he feels ridiculed by all the attention my letters are bringing him, then that's just too darn bad. Rumsfeld's arrogance has brought this upon himself.

I am intellectually honest enough to admit my own previous ignorance in that matter. I only wish that Rumsfeld had the same intellectual honesty. If I am doomed to run for cover, then he will obviously provide intransigent ivory-tower academics with an irresistible temptation to deny both our individual and collective responsibility to live in harmony with each other and the world before you know it. The next time he decides to turn back the clock and repeal all the civil rights and anti-discrimination legislation now on the books, he should think to himself, cui bono? -- who benefits?

Was Rumsfeld just trying to be cute when he said that he can change his socially inept ways? I sure hope so, because he has two imperatives. The first is to play on people's conscious and unconscious belief structures. The second imperative is to blame our societal problems on handy scapegoats. By refusing to act, by refusing to institute change, we are giving him the power to pander to our worst fears. Even when Rumsfeld isn't lying, he's using facts, emphasizing facts, bearing down on facts, sliding off facts, quietly ignoring facts, and, above all, interpreting facts in a way that will enable him to create widespread hysteria.

There should be a law against this, and hence, by extension, we can never return to the past. And if we are ever to move forward to the future, we unequivocally have to exemplify the principles of honor, duty, loyalty, and courage. While it is essential -- and among my highest priorities -- to draw a picture of what we conceive of under the word "anticonfederationist", there is no such thing as evil in the abstract. It exists only in the evil deeds of evil people like Rumsfeld. You might think this is all pretty funny now, but I doubt I'll hear you laughing if, before long, he is successfully able to spoil the whole Zen Buddhist New Age mystical rock-worshipping aura of our body chakras.

Perhaps Rumsfeld's outrage at complaints about him is indicative of his self-esteem and value system, but remember that in a recent essay, he stated that hanging out with hypersensitive dorks is a wonderful, culturally enriching experience. Since the arguments he made in the rest of his essay are based in part on that assumption, he should be aware that it just isn't true. Not only that, but his idiotic claim that disorderly, stinking scalawags are more deserving of honor than our nation's war heroes is just that, an idiotic claim. While obtuse Pyrrhonism is widespread and growing stronger as it permeates school systems, universities, and the media, it's easy for us to shake our heads at his foolishness and cowardice. It's easy for us to exclaim that we should create greater public understanding of the damage caused by his inveracities. It's easy for us to say, "I draw strength and courage from knowing that most people comprehend the crusade to stop Rumsfeld and are supportive of my role in it." The point is that it's easy for us to say these things, because Rumsfeld is essentially describing a situation that does not exist. Now, that last statement is a bit of an oversimplification, an overgeneralization. But it is nevertheless substantially true.

Some people are responsible and others are not. Rumsfeld falls into the category of "not". Please humor me for a moment while I state that he asserts that his vices are the only true virtues. That assertion is not only untrue, but a conscious lie. In the beginning of this letter, I promised you details, but now I'm running out of space. So here's one detail to end with: One thing that Donald Rumsfeld does well is turn once-flourishing neighborhoods into zones of violence, decay, and moral disregard.

Re:Impeach George W. Bush @# +1 ; Patriotic @# (0)

Anonymous Coward | about 12 years ago | (#3380064)

I didn't read your message because it seemed dumb and off-topic but all I can say is I agree: I think we should use JPEG compression on Rumsfeld -- I think we'd get some good results.


Re:More advice (4, Funny)

Admiral Mouse (3430) | about 12 years ago | (#3379954)

And get this... apparently images are not the only things that computers can compress. I've just learned that there are a slew of programs out there that can compress text-data with amazing ratios.


I can not wait... (0, Offtopic)

fuckthetux (234672) | about 12 years ago | (#3379794)

i am on 14k4 :(

Parent post off topic? (1, Offtopic)

NanoGator (522640) | about 12 years ago | (#3379876)

Somebody modded the parent post here down as off-topic. Would a moderator please re-read the post?

a.) It was on topic

b.) It was funny

Re:Parent post off topic? (0)

Anonymous Coward | about 12 years ago | (#3380038)

a.) It was on topic

yes, it was. The problem is that the comment was useless and equivelant to "f1rst p0s7 d00D!"

b.) It was funny

not even close to being funny. I've seen more funny on a Martha Stewart 24 hour marathon than that.

JPG? (4, Funny)

ar1550 (544991) | about 12 years ago | (#3379813)

Compression? I'd just been renaming my .bmp's to .jpg - you mean I actually have to "compress" them to a .jpg to gain any benefit? Wow, my readers will sure be pleased. Next, you'll be telling me that my Flash-only websites should use shapes & instances instead of manually manipulating every pixel.

Re:JPG? (2)

jedrek (79264) | about 12 years ago | (#3379901)

? I'd just been renaming my .bmp's to .jpg - you mean I actually have to "compress" them to a .jpg to gain any benefit?

You laugh, but I do have a couple pictures I've gotten of people over the years (that would be 14 years at the end of this summer) that are small (res wise) .JPGs, about 400-600kb each. They are, of course, 'uncompressed JPGs', meaning BMPs and TIFFs renamed to .JPG. I also have a couple of images -- real JPGs this time -- about 3000x2000 (the size of the scanner at 150DPI) where the photo itself is about 400x300px somewhere in the middle of that.

The rest is white.

So, yeah, this article could help some people out... but still:

Worst thread ever

Re:JPG? (1)

Com2Kid (142006) | about 12 years ago | (#3379906)

Compression? I'd just been renaming my .bmp's to .jpg - you mean I actually have to "compress" them to a .jpg to gain any benefit?

Don't laugh, I have had this happen to me before, people 'compress' a .bmp by renaming it .jpg. . . .

I have had people aiming for CS degrees do this. . .

Ok admittedly it was late at night and the person in question was having a VERY bad day. ^_-

Re:JPG? (1)

wolf- (54587) | about 12 years ago | (#3380067)

Its ok when they "email" you the "compressed images". I hate it when windows based website designers actually put bmps on their websites. arg!

Re:JPG? (1)

rapidweather (567364) | about 12 years ago | (#3380021)

I make some of my images using GIMP on a Redhat Linux 7.1 machine, and in my rush to get them up, I just saved them as .gif. Next time I'll try .jpg, and see what GIMP can do in the way of file sizes for a comparable image.

Layne Staley-lead singer of Alice in Chains-dead (-1)

Patrick Bateman (175284) | about 12 years ago | (#3379815)

I just heard some sad news on the radio - "Alice in Chains" lead singer Layne Staley was found dead in his Seattle home this morning. There weren't any more details. I'm sure everyone in the Slashdot community will miss him - even if you didn't enjoy his work, there's no denying his contributions to grunge rock. Truly an American icon.

Calling a cat a cat. (1, Offtopic)

pinkpineapple (173261) | about 12 years ago | (#3379816)

It's unfortunate that the JPEG format ends up being described as the JPG, due to DOS naming constraints. Are we doom to see the usage of 3 name extension only in the future due to this lack of vision from the early implementers? I for one would tend to favor embedded MIME support and the removing of file extensions.

PPA, the girl next door.

Re:Calling a cat a cat. (0, Funny)

Anonymous Coward | about 12 years ago | (#3379871)

I wholehartely agree. Can an editor change the title to "image/jpeg Compression"?

Re:Calling a cat a cat. (0)

Anonymous Coward | about 12 years ago | (#3380065)

You mean GNU/image/jpeg

Re:Calling a cat a cat. (0)

Anonymous Coward | about 12 years ago | (#3379914)

Or maybe it's just because those guys ain't such "experts" after all.

Re:Calling a cat a cat. (0)

Anonymous Coward | about 12 years ago | (#3379929)

You guys are the best, a pointless MS slam to a pointless post... It's not as if the usage of "jpg" in an english sentence realy confused anyone out there. Or to improve readability should we always go with the long form of "Joint Photographic Experts Group"? And no I refuse to speak the full mime type in conversations either. I guess I should be glad we don't see requests for a link to the resource fork just so mac people can read it.

Re:Calling a cat a cat. (3, Funny)

Anonymous Coward | about 12 years ago | (#3379940)

Yes, but using "JPG" instead of "JPEG" saves a byte of bandwidth.

Re:Calling a cat a cat. (2)

ImaLamer (260199) | about 12 years ago | (#3379952)

It's quite a problem working on a XP/2000/9x machine which won't show me mpeg files when looking for mpg and the reverse.

There is little need for extensions what so ever when you are working in a graphical environment. The GUI can assign icons to types [if someone hasn't already monopolized on that media type and got their icon on the 'top].

In a console based environment there is also little need. Most users know what files are what and if they don't there is sometimes a color coding involved which helps you know what you can edit. [of course jpeg is little use to a console user].

As far as I know linux has no problem reading the content headers of files but I'm not an expert, just a user. I assume this is done on the interface level, somone speak up!

Re:Calling a cat a cat. (2)

Phroggy (441) | about 12 years ago | (#3379958)

It's unfortunate that the JPEG format ends up being described as the JPG, due to DOS naming constraints. Are we doom to see the usage of 3 name extension only in the future due to this lack of vision from the early implementers? I for one would tend to favor embedded MIME support and the removing of file extensions.

Here here. I'm sick of hearing people talk about HTM files. Mention assembly language, and they reply "oh, you mean ASM?" Even Windows isn't this dumb anymore; why haven't the users gotten better?

These morons are offensive to us Mac users, and they're polluting Linux too. Anyone have any suggestions for putting a stop to this?

So fucking screwey... (-1)

OsamaBinLager (532628) | about 12 years ago | (#3379995)

As if a file extension which is maintained no matter what OS you're on is the end of the world.

Fucking Mac freaks. Fuck, it doesn't even make life harder for you on Macs to use files with an extension, so why are you whining? I'll tell you why - because you're an elitist pig.

Re:Calling a cat a cat. (1)

iotaborg (167569) | about 12 years ago | (#3380019)

Just looking around on my OS X machine, I see a few extensions of type ".kext", ".component", ".dfont", ".plugin"... So, we're doing fine I suppose...

Re:Calling a cat a cat. (0)

Anonymous Coward | about 12 years ago | (#3379959)

JPEG isn't a format, JFIF is.

Intellectual property (-1)

October_30th (531777) | about 12 years ago | (#3379818)

But just like MP3, JPEG makes it so much easier for people to violate the copyright owners' intellectual property! This algorithm and all the implementations must be locked up just like it was with DeCSS.

Only the media corporations that provide the content we all love so much have real use for JPEG.

slow day at slashdot (1, Informative)

deathscythe257 (309424) | about 12 years ago | (#3379819)

umm... huh... I was hoping there might be a news article here.

Parent post a Troll? (2)

NanoGator (522640) | about 12 years ago | (#3379886)

I think he had a valid point. This article really does get filed under 'Duh'. There's a difference between having a negative opinion and trying to be offensive.

Frankly, I agree with him.

JPG Compression - Hmmmm (0)

Anonymous Coward | about 12 years ago | (#3379825)

I've started to care a lot less about server-side bandwidth with the dawn of free web-hosting.

Power Switch - The Energy Saver (5, Funny)

wadetemp (217315) | about 12 years ago | (#3379829)

In other news:

Anonymouse Cowarde has posted an article entitled "Power Switch - The Energy Saver". An article for geeks and computer owners showing how they can significantly reduce the amount of power they use by turning off your computer when you're not using it, using one of the most common buttons found on the front of most PCs. If you own a computer and don't yet have knowledge in the field of energy, you should find this very interesting indeed - Save money on electricty and please your significant other at the same time with a quieter room and lower energy bill. They also talk briefly at APM.

Re:Power Switch - The Energy Saver (0)

Anonymous Coward | about 12 years ago | (#3380054)

Question though: How many people that visit Slashdot are ever *not* using their computer? See, this could be a problem. Maybe the best way to conserve power is to have people join some sport or something (i can hear the laughing already). ;-)


Um, I thought this was common knowledge... (0, Redundant)

Millennium (2451) | about 12 years ago | (#3379834)

It's fairly simple. Use JPEG for photos, where the compression artifacts won't be noticeable and the bandwidth savings are most helpful. Use PNG for computer-generated stuff like screenshots, and run them though pngcrush (always use the highest compression for PNG's that you make available for download; because they're lossless, you don't lose any quality).

Has this become uncommon knowledge already?

Re:Um, I thought this was common knowledge... (1)

RatOmeter (468015) | about 12 years ago | (#3379935)

Yes, I thought it was common knowledge also. But I've noticed that there seems to be very little decrease in the use of GIF files in web sites. It seems like a majority of sites still use GIF's for their small images... tiled backgrounds, arrow pointers, etc. Besides not compressing the image as efficiently, GIF's also come with potential baggage [burnallgifs.org], which is even more reason to choose JPEG over GIF. What's really goofy is, when I pointed my browser to that URL on tweaktown, a banner ad for Kingston memory appear... as a GIF!

The article may have been apropos on tweaktown, given that site's intended target audience. I *don't* think the article was apropos for /.

Re:Um, I thought this was common knowledge... (2)

Ed Avis (5917) | about 12 years ago | (#3379989)

The biggest bandwidth saving on many sites would be to generate PNGs with an appropriate number of colours. Very often you can reduce your image to 8, or even 4 colours with very little loss of quality but a big reduction in image size.

When... (2)

Decimal (154606) | about 12 years ago | (#3379836)

When are we going to start evolving these algorithims? It would have to be done by a really fast computer, but it's been shown that natural selection applies to computing as well. I'd imagine that it is possible to come up with an algorithim that's lossless and still as small as any equivalent .jpg file. Nature can come up with things we never even imagined. This technique has been used to create a sorting program that is smaller works faster than any we ever created manually. And we often can't figure out how it works. Not a clue!

Re:When... (1)

Paul Komarek (794) | about 12 years ago | (#3379966)

I believe you are referring to genetic algorithms. They're not a cure-all for problem solving. There are some good applications for genetic algorithms, but I expect that finding good compression algorithms for images is not one of them. As for evolving image processing algorithms, they are always evolving. But throwing a random AI technique (genetic algorithms, neural nets, simulated annealing, whatever) at a random problems is unlikely to help that process. All of these are simply nonlinear function approximators, and choosing the right method often require a great deal of human labor. Once the model and algorithm have been chosen, there is no guarantee that any of the mentioned algorithms will converge to optimality within a finite period of time.

It's not that we're sitting on our butts, too lazy to throw our wonder algorithms at problems that would save the world. It's that we don't have any wonder algorithms. If we did, we'd probably not know how to ask the questions anyway. And there are those who think that once we had such algorithms and asked the right questions, we wouldn't understand the answer anyway -- but that's a different matter altogether. ;-)

-Paul Komarek

Re:When... (2)

Phroggy (441) | about 12 years ago | (#3380039)

When are we going to start evolving these algorithims? It would have to be done by a really fast computer, but it's been shown that natural selection applies to computing as well. I'd imagine that it is possible to come up with an algorithim that's lossless and still as small as any equivalent .jpg file.

You mean like PNG? The problem is browser support - old browsers may not render a new format consistently. Keeping two versions of every graphic and deciding which to send to the browser based on what it can handle is a pain. Having a significant percentage of potential customers see broken links all over everything is unacceptible.

*blinks* and this appears on the front page.. why? (5, Insightful)

Aanallein (556209) | about 12 years ago | (#3379846)

Short run down of the linked-to article:
Non-compressed images have a large filesize and cost a lot of bandwidth, compressed images look almost as good and cost less bandwidth.
Guide to compress images in PSP 7: save, move slider.
conclusion: compressing is good, hope you found this useful.

*shakes his head sadly* Slow down are fine, but c'mon - we're geeks you know; we can be expected to at least know *some* things...

*kicks self* (1)

Aanallein (556209) | about 12 years ago | (#3379857)

Slow days, slow days... not slow down.
Though I should slow down with typing. No time though - must read more pointless articles... :)

Gah, and then of course I replied within the two minute delay with the "Slow Down Cowboy!" message - how appropriate.

Re:*blinks* and this appears on the front page.. w (3, Insightful)

weave (48069) | about 12 years ago | (#3379885)

Really... I also found it hilarious that the pages are loaded with shockwave ads and large 256 color gif files for simple border bits that could be done in 4 colors.

Oh well, maybe I'll write an article about how to reduce size of GIF files using a smaller color pallete and turning off dithering so it can compress better... :-(

This article needs to be shown to just about every web graphics shop out there, but not to us self-righteous nerds! :)

Re:*blinks* and this appears on the front page.. w (1)

dr00g911 (531736) | about 12 years ago | (#3379994)

FWIW: slight addendum.

In PS7, choose "Save for Web-->Jpeg" and not "Save-->Jpeg"

Why? The images come out significantly smaller / more optimized -- and, specifically for those of us on the Mac, don't have the extra 16k of resource fork / icon data.


jpg vs gif (2)

terradyn (242947) | about 12 years ago | (#3379849)

Although jpg compression is definitely helpful, the article forgets to mention that two image formats are supported by all browsers. GIF being the second. GIFs should be used for vector based graphics and provides a better overall quality/size advantage when done right. Many non-professional webpages confuse the distinction and make solely jpg or gif based websites. He should also have explained the compression techniques using photoshop as that is a much more popular package (although I understand that many home grown websites might be using PSP, they are also the ones that don't really care about bandwidth since they're using geocities or other free hosts).

Re:jpg vs gif (1)

fire-eyes (522894) | about 12 years ago | (#3379919)

Too bad there's all that LZW patent / fee bullsh*t. Which is why I won't use .gif anywhere on any site that I run.

This isn't just paranoia, you can be fined for this.


GIMP anyone? (2)

Sean Clifford (322444) | about 12 years ago | (#3379955)

Uh, what about GIMP [gimp.org]?

Sure, PhotoShop is nice - if you're running a Mac or Microsoft Windows(TM) box and a grand laying around. Paint Shop Pro is pretty nice, does most of what PhotoShop does for a tenth the price - if you're suffering under a MS OS. But hey, you can download GIMP [gimp.org] for FREE. Heck, they even have a Microsoft Windows(TM) port [gimp.org]. Sure, you can't save GIFs or dick with TIFFs, nor can you do a lot of stuff you can do in PhotoShop.

However, GIMP is great for most image manipulation needs.

Re:GIMP anyone? (1)

pdiaz (262591) | about 12 years ago | (#3379998)

Of course you can save .gif/.tiff files with gimp: apt-get install gimp-non-free (or consult compilation options)

Instead of GIF, use PNG or SWF (5, Informative)

yerricde (125198) | about 12 years ago | (#3380041)

Although jpg compression is definitely helpful, the article forgets to mention that two image formats are supported by all browsers. GIF being the second.

In addition, 4.0 and newer browsers support Portable Network Graphics (PNG).

GIFs should be used for vector based graphics

No they shouldn't [burnallgifs.org]. Use PNG for still images. Use SWF (now an open format [openswf.org]) or MNG (not much browser support yet [libpng.org] but works in Mozilla and Konqueror) for animations.

and provides a better overall quality/size advantage when done right.

PNG can be 10% smaller than GIF when crushed properly [sourceforge.net].

Re:jpg vs gif (1)

Phroggy (441) | about 12 years ago | (#3380055)

He should also have explained the compression techniques using photoshop as that is a much more popular package (although I understand that many home grown websites might be using PSP, they are also the ones that don't really care about bandwidth since they're using geocities or other free hosts).

Why anyone would use a photo-editing behemoth like Photoshop for simple Web graphics has always been beyond me. I haven't really looked at Paint Shop Pro since around 1994-1995; it's Windows-only and thus useless to me.

Last I heard PSP was still shareware, but Photoshop is definitely really expensive. Two questions: 1) are these really the tools of choice for a majority of people who make Web sites? 2) what percentage of those people actually use the software LEGALLY?

Memories of JPEG (2)

Renraku (518261) | about 12 years ago | (#3379850)

JPEG has been around almost as long as I can remember the Internet. I remember spending long hours downloading single pr0n pics from Lynx using the Kermit protocol. Too bad half of 'em were zipped bitmap files instead of JPEGs.

Am I the only one annoyed by dropping the e? (0)

Anonymous Coward | about 12 years ago | (#3379854)

It's JPEG, dammit! Never has been "JPG [sic]", never will be. The dropped e is a figment of history from the days of 8.3 DOS filenames, and Unix never had that limitation (although there was 11 character limits), using "JPG" on a pro-open-source website is not only insultive, it is offensive to loyal Unix users.

Re:Am I the only one annoyed by dropping the e? (0)

Anonymous Coward | about 12 years ago | (#3379993)

This is for fast downloading!, without one letter we can economize a lot of bytes on file names !.

What's the best way to speed up your connection? (4, Funny)

NanoGator (522640) | about 12 years ago | (#3379856)

Q: What's the best way to speed up your connection?
A: Run less data through it.

I can write an article about this if Slashdot is interested.

LOL (3, Funny)

Dwedit (232252) | about 12 years ago | (#3379860)

As you can see from the 25:1 compressed image above, there is really not much of a difference in terms of image quality from the original image at 2:1 - but a save of 44.6kb in file size. Consider this as a practical example - a new piece of content you post has ten images in it, for simplicity reasons at 63.2kb each (632kb in total), we save a total of 465kb, seemingly not a great deal on an individual basis.

Now say 2000 different people read that same review uncached, we save a total of roughly 908mb in outbound data bandwidth for that single review. If 5000 people were to read that review, we are talking gigabytes of bandwidth which can be saved through compression, 2.27gb to be exact. I'll let the stunning numbers speak for themselves.

Sorta ironic how thousands of people are downloading that article right now!

This will be a common conversation... (3, Funny)

Navius Eurisko (322438) | about 12 years ago | (#3379865)

Web Designer 1: "Hey, this JPG compression will save our average 56k user about 5 seconds on load time."

Web Designer 2: "That's means we can load even more useless content on our website and they won't notice the difference!"

Web Designer 1: "As well as include more popup and banner ads, too!"

More Interesting News (1)

roryh (141204) | about 12 years ago | (#3379866)

This is hardly news for the /. crowd. Isn't it supposed to be "News for Nerds"?. More interesting, IMHO, is the fact that Photoshop is out for MacOS X. I'll be interested in what effect this has on the uptake of the OS, and whether it might ever lead to Photoshop on *NIX.

Re:More Interesting News (3)

maggard (5579) | about 12 years ago | (#3379942)

As the original subject (JEPG - a revolution!) is pretty much useless this at least is more interesting:
More interesting, IMHO, is the fact that Photoshop is out for MacOS X. I'll be interested in what effect this has on the uptake of the OS, and whether it might ever lead to Photoshop on *NIX.
Yes, I think this will increase the uptake in MacOS X. Lots of graphics folks have been holding out for this, apparently it's a great implementation and will indeed likely drive much of their marketplace (just think of all of the plug-ins that will need to be upgraded.) The spillover should be a shot in the arm for the whole Mac software market and increase pressure on everyone to make the switch.

As to this increasing the odds of Photoshop on any other Unix - I doubt it. The MacOS X port is to the proprietary backwards-compatible-with-MacOS "Carbon" layer and not writing to the BSD side of things. Thus it's really the old MacOS Photoshop rewarmed and running mostly on a cleaned-up set of APIs. The other changes that have been made are apparently mostly for interaction with the Quartz graphics layer and Aqua UI, again Apple-proprietary.

The next-gen evolution will likely be to MacOS X's Cocoa layer, yet again Apple proprietary. Thus unless someone ports Apple's Carbon library to another Unix or Apple decides to make Cocoa cross-platform along with support for a differing rendering layer we're unlikely to see any of this having any relevance to other Unix's. Of course they can all now talk seamlessly to Photoshop through scripting so they're not entirely out in the cold.

aw shit! (3, Funny)

paradesign (561561) | about 12 years ago | (#3379868)

you mean i shouldnt have been using TIFs this entire time?!? no wonder my site loads so slow.

i use LZW, if that helps?

Wayback machine (2)

freeweed (309734) | about 12 years ago | (#3379875)

Why does it feel like 1994 all over again?

JPEG'ing images has been par for the course for any competant web designer since the very incarnation of the WWW.

This is like having a 'news' article to the effect of

"Make your HTML code smaller! Learn what the tags actually are and throw out FrontPage!"

Oooo gee, wow!

Re:Wayback machine (1)

extra88 (1003) | about 12 years ago | (#3379928)

Actually in 1994, commonly used browsers did not have support for inline JPEGs.

Re:Wayback machine (2)

freeweed (309734) | about 12 years ago | (#3379992)

Good point, hell, I remember versions of Mosaic that didn't seem to support *anything* :)

Point still stands though.. JPEG support is not only VERY (relatively) old, but proper JPEG use, if anything, was far more important way back when. Try accessing a modern 400K/page site with a 14.4 :)

Re:Wayback machine (4, Funny)

GigsVT (208848) | about 12 years ago | (#3379938)

Man, now I am going to have to redesign my page to get rid of all those uncompressed TIFFs.

Watered down article? (2)

winternj (530214) | about 12 years ago | (#3379883)

For slashdot, I would expect at least something on the order of a tutorial, or perhaps some study on a better compression method for jpeg. obviously 99% of the readers here know that jpeg can be compressed.

Re:Watered down article? (0)

Anonymous Coward | about 12 years ago | (#3379937)

I would say closer to 100%. In reality, I would like to see some slashdot articles on how to setup Linux programs and hardware. We preach that Linux is so good, but the method of learning how to do anything isn't very clear.

How coincidental. (2)

Cutriss (262920) | about 12 years ago | (#3379884)

Interesting that this would be posted no less than three days after Penny Arcade [penny-arcade.com]'s screenshot rant from Wednesday.

I have to say that I agree with Tycho and Gabe on this one. All too often I'm seeing websites post crappy images claiming that they show intricate detail of upcoming software, yet they compress it to the point that it looks like it came out of one of these [goatse.cx].

Re:How coincidental. (2)

Ed Avis (5917) | about 12 years ago | (#3380011)

It's true, JPEG sucks for screenshots. Yet it can be a lot smaller than GIF or even PNG, so people may use it despite the loss of quality.

I'd like to see some kind of 'lossy PNG'. PNG files are compressed using the LZH algorithm first used in pkzip, and now used in zlib, gzip and all sorts of places as well as PNG. This works by having a 'sliding window' where the last 32Kbyte or so of data is stored, and then looking back through that window to see if the current sequence of bytes has been output previously. If so, just output a referral back to where the sequence occurred before.

But what if you modified zlib so it didn't require an exact match? You might say that having one pixel in every ten out of place, or set to a 'close enough' colour (eg dark grey instead of black), is good enough to find a match. Then you could generate PNG images which lost some of the original information, but wouldn't look quite as sucky as JPEG. And any ordinary PNG viewer would be able to display them.

I don't know whether this would work well in practice but it's worth trying. Probably for dithered images it would be great but screenshots wouldn't be helped much without losing noticeable quality.

Whoops! (5, Funny)

CaseyB (1105) | about 12 years ago | (#3379888)

Pardon me, I seem to have accidentally stepped into a conversation from 10 YEARS AGO.

What a useless post... (0)

Anonymous Coward | about 12 years ago | (#3379895)

What a useless slashdot post.

1) That website provided little to no useful info for the average webmaster - who, if they haven't heard of JPG compression, don't deserve that title.

2) Poor Tweaktown is trying to save bandwidth, so what we do... we SlashDot 'em. Poor bastards probably wish JPG2000 was out yesterday

3) They'd save even more money if they lost the banner advertizements :P

Well at least I get to write this lame post on Slashdot which will be loaded by hundreds of thousands of people each wasting exactly 560 bytes of Slashdot's bandwdith. Mwahaha

Hmm... (1)

weird mehgny (549321) | about 12 years ago | (#3379896)

In the conclusion, the author mentions GIF. But what about .PNG? Yes, I know that JPEG as a rule of thumb is better than PNG for photo-like images. But for many images... indeed for anything smaller than ~100x100 pixels, but also in random cases for bigger images, .PNG is better than JPEG. Even images that appear to be very complex, and images that don't do well at all as .GIF's, sometimes turn out EXCELLENT as .PNG's, way smaller than JPEGs and with perfect quality.

This is not the case for their sample image, but, umm, I'd just like have said anyway that some people are way too quick to save their pics as blurry JPEGs without trying the alternatives.

Damn Flash (offtopic) (0, Offtopic)

fire-eyes (522894) | about 12 years ago | (#3379898)

I tried many times to view that page with mozilla built yesterday, but it kept bothering me that I didn't have the flash plugin (ads?).

So i installed them, and it would just hang. Tried to hit stop after the text was there, after removing the plugins, and the page would go blank.

Too much trouble, so I didn't bother. Good job web page team.

Wow! I never knew that! (0)

Anonymous Coward | about 12 years ago | (#3379909)


Compressed images == less file size == less bandwidth! What an insightful discovery, I could have never figured it out myself!


Come on..... (5, Insightful)

josh crawley (537561) | about 12 years ago | (#3379923)

Now, I can understand if slashdot wants to put techie reviews or such other geek stuff. That's understandable, in the case of YRO, company product release (that april spoof about sponsoring products was true, wasnt it?), and software issues.

HOWEVER, this is a geek site, which we talk as deeply as going about SMP on x86 systems and remodding systems into other cases (mechanics and engineering, lest that be software or hardware). However, that journalistic line (if there even was that line) has been crossed with this idiotic article. Let's re-read this again to see if it doesnt state the obvious. Also, I'm going to _assume_ that techie people on this website (most all) knows that jpeg is a compression....

Compression - The Bandwidth Saver

Hell, even non-techie people still know that if I zip that file, it doesnt take as long.... This article just insults our intelligence. Slashdot is becoming more and more like TechTV for the net.

And as a last mote, moderators, pay attention to *important stuff* below every post. This article is anything but offtopic.

Old news. (0)

Anonymous Coward | about 12 years ago | (#3379930)

Come one, this is so stupid!

I thought the JPEG vs GIF and later JPEG vs PNG thing had been resolved _years_ ago!

How did this get into the front page?

This should be "News for Nerds."; does the editor honestly think that an average geek (nerd) wouldn't know this stuff already? I bet a number of ./'s readers could actually _implement_ JPEG if they where given the standard.

Choose your compression with care... (5, Interesting)

tjwhaynes (114792) | about 12 years ago | (#3379934)

While compressing your images should be right up there on the Web designer 101 course, sometimes I despair that the wrong types of compression are chosen.

JPEG is an excellent compression method for photographic images, both colour and greyscales. The image distortion is not noticeable by most people even at high compression ratios and the resulting image is close enough to the original.

JPEG is NOT an excellent compression method for line diagrams, maps and bitmaps featuring a limited colour palette - the artifacts created by the transforms used by the algorithms blur rapid changes in colour and can make text unreadable. Even worse, for most diagrams, PNG lossless compression yields smaller results because of the limited palette and large amount of redundancy inherent in the data.

JPEG 2000 promises even better compression ratios with superior image quality. Wavelet compression methods tend to reduce the amount of blur caused by the discrete cosine transforms and are better at handling rapid changes in colours. But that doesn't mean that it is a blanket solution.

I also look forward to the day when SVG is a widely available and widely supported browser option. We can all benefit when complex layouts can be described in terms of vectors and colour fills rather than overlarge and complex bitmaps for the classic web page touches like 3D colour balls and arrows. That will also save bandwidth while increasing the flexibility and variety of images on the web.


Toby Haynes

Re:Choose your compression with care... (0)

Anonymous Coward | about 12 years ago | (#3380059)

Adding my emphasis:

"Even worse, for most diagrams, PNG lossless compression yields smaller results..."

Huh? I'm tired. Please explain how it's a worse thing for a PNG to produce a smaller result?

JPEG is not appropriate for all images (4, Informative)

Ryu2 (89645) | about 12 years ago | (#3379939)

The article didn't discuss the merits of other formats vs. JPEG enough. Namely, non-photograhic images, with few colors and mostly large solid areas, such as icons, bullets, line drawings, diagrams, charts, etc. are not optimal for JPEG.

In such cases, GIF and PNG will yield much better compression than JPEG, and also look nicer, since they're lossless. Compressing such images with JPEG will give you ugly "ringing" artifacts, since the lines are essentially infinite-frequency "spikes" which you can't capture completely.

But... (1)

iONiUM (530420) | about 12 years ago | (#3379943)

We should keep this quiet. If advertisers figure it out, we'll get even more pop up windows, crammed with more crap than ever before, because it'll be cheaper. Keep them using bitmaps! Or Gifs even!

I wish we could moderate articles. (0)

Anonymous Coward | about 12 years ago | (#3379951)

Because this one would be (Score: -1, Redundant)!

Shenanigans? (0)

Anonymous Coward | about 12 years ago | (#3379964)

An article from www.tweaktown.com, submitted by Mr Tweak, who happens to be the webmaster of www.tweaktown.com. Next thing we know, we will be getting articles about stretching your anus from George Oatse, who happens to be the webmaster of goatse.cx

Now if only... (3, Funny)

ZoneGray (168419) | about 12 years ago | (#3379976)

Now if only they could convince people to build pages that have fewer than 100 GETs, it might actually make a difference.

Impeach Hemos (0)

Anonymous Coward | about 12 years ago | (#3379977)

As can be easily sdeen from this article, Hemos has no idea what a computer is and is currently on a tropical island approving stories by avain carrier(and not even ip, but Lan Mangaer 2.x). Therefore we must IMPEACH HEMOS

Quality and depth of articles (lack thereof) (0)

Anonymous Coward | about 12 years ago | (#3379978)

Has ZDTV or CNET News.com bought out Slashdot or something? I seem to have missed the annoucement...

How jpegs work. (4, Informative)

furchin (240685) | about 12 years ago | (#3379981)

I got trapped into clicking the link to the article, thinking it could be something useful about jpeg compression and how it works. The story certainly implied that. How disappointed I was, and I agree with most people that this is one of the dumbest stories ever. This kind of story belongs in a site for amateur wanna-be web designers, not geeks. Anyway, since I've gotten all caught up in this, and you're here too, maybe we can have a useful discussion on How JPEG Compression Works.

I am by no means an expert, and I believe this is a gross simplification of the process, but here is what I think happens. The jpg alg breaks the image apart into 8 pixel by 8 pixel subimages. (Don't ask how it handles pictures that are not n*8 x m*8 in size). Then it treats each of those images with a process very similar to principal component analysis, where a set of representative images are given associated multipliers of how much of that image to add into the reconstructed original image the user is trying to get. These representative images are ordered from least to most detailed, and since they are known to both the compressor and the uncompressor (depressor? :), only the associated values need to be stored. I believe the first image deals with how much darker the left half is than the right half of the image, the second does the same thing horizontally, the third deals with how much darker the leftmost quarter of the image and the third quarter of the image are darker than the other two, and so on...

So how does one adjust image quality / compression? Well every possible 8 x 8 picture can be represented with 64 of these representative images. However, since the 64th deals with *really* minute details, then you can get a decent reconstruction using just 63. It all depends on the image you are trying to compress, but can probably get away with even just the first 20 of the basis images. Oh, for the record, I'm talking about grayscale here. I think you'd need to ramp things up by a factor of 3 to do rbg.

If someone wants to fill in any gaps or factual inaccuracies, certainly do so.

Whoa there.. (1)

toby360 (524944) | about 12 years ago | (#3379983)

How'd something like this get slashdotted? Shouldn't a web site that deals with quantum mechanics, astrophysics, supercomputers, wireless networking standards, etc. be beyond "jpeg" compression? Thank you for wasting 5 minutes of my life and telling me that you can compress jpegs. Sorry if this seems like flame, but someones got to say something.

Does GIF creation require Unisys license fee? (0)

Anonymous Coward | about 12 years ago | (#3379985)

If so, when will this bloody patent expire?
I thought the patent expired last year, but I have read contradictory information all over the place.

News for NERDS (1)

eander315 (448340) | about 12 years ago | (#3379996)

"If you own a website and don't yet have knowledge in the field of JPG compression, you should find this very interesting indeed..."

If this statement is true, you probably aren't reading it on Slashdot.

compress text too (1)

lmd (413644) | about 12 years ago | (#3380000)

This is slightly off topic but almost anyone can compress text, too. Of course, JPG compression is better than text compression but every little bit counts.

You can download a copy of mod_gzip here [remotecommunications.com] for Apache [apache.org].

Hail the king ! (1)

tandr (108948) | about 12 years ago | (#3380013)

MP3 compression !

I cannot even imagine what would happens to bandwidth if all MP3 files will be uncompressed... Total slashdotting probably

Seriously people... (1)

quantax (12175) | about 12 years ago | (#3380014)

Jesus, come on here Slashdot, why the hell would you post this as a frontpage item? This is like posting 'Newbies Guide to Webpages'. Lets use a little more discression when posting stuff, esp rediculous crap like this. If your reading slashdot and you do not have any knowledge of JPEG compression, you should probably kill yourself for the greater good of humanity. This is some basic stuff that even my little bros (who only know how to browse the web, talk with friends on AIM, and make basic webpages) are familiar with. Don't insult us with this sort of material.

There should be a law (1)

rburkatpinkbike.com (445943) | about 12 years ago | (#3380017)

As an ISP company I find it very offensive that such advents in technology will cost us money in lost sales revenues.
Since reading about this revolutionary JPEG format I am appalled that the ISPs are not lobbying the government for an injunction on this technology. It says 25:1 reduction in bandwidth.....does this mean our revenues will fall by a factor of 25 if all our customers adapt this new technology? That is appalling. What can we do to stop this?
- :) Sweet article!

wow!! (1)

Morgahastu (522162) | about 12 years ago | (#3380034)

This just in: things that cost less save you money! Oh was I stating the obvious. Sound familiar though? Compression saves you bandwidth!

aol recompresses your jpegs (5, Informative)

Chaostrophy (925) | about 12 years ago | (#3380050)

At my last job, we wondered why our carefully tuned images looked like shit on AOL. We found they were recompressing our jpegs to make them much smaller (and thus lower quality). So we now send AOL really high quality jpegs so that our images don't get trashed as badly by AOL.

Evil (1)

t_allardyce (48447) | about 12 years ago | (#3380052)

Lossy compression is evil, it is the polution of our time. But, like the polution of the real world, without it we would be held back, just as without cars and planes and factories we would be held back too.

Bad compression artifacts and degredation after generations of compression and editing piss me off more than anything in the world.

Spam... (0)

Anonymous Coward | about 12 years ago | (#3380061)

A story submitted by "Mr.Tweak" about a website called TweakTown. So those Slashvertisements [slashdot.org] weren't an April fool prank, hmm? If anyone would like to personally voice their disgust with Mr. Cameron "Tweak" Wilmot over this obvious co-opting of Slashdot, why don't you give him or a call or drop by? I'm sure he'd appreciate it.

Wilmot, Cameron
295 Manifold Street
Camperdown, VIC 3260 AU
Load More Comments
Slashdot Account

Need an Account?

Forgot your password?

Don't worry, we never post anything without your permission.

Submission Text Formatting Tips

We support a small subset of HTML, namely these tags:

  • b
  • i
  • p
  • br
  • a
  • ol
  • ul
  • li
  • dl
  • dt
  • dd
  • em
  • strong
  • tt
  • blockquote
  • div
  • quote
  • ecode

"ecode" can be used for code snippets, for example:

<ecode>    while(1) { do_something(); } </ecode>
Sign up for Slashdot Newsletters
Create a Slashdot Account