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| Porn Users Forum » Can someone clue me in? |
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| 03-05-10 02:35pm - 5406 days | Original Post - #1 | |
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messmer (0)
Disabled User  Posts: 2,582 Registered: Sep 12, '07 Location: Canada |
Can someone clue me in? I keep reading in reviews about "compression artifacts" showing up in some DVDs. How would that manifest itself? I've never heard of the term before. Thanks. | |
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| 03-05-10 02:46pm - 5406 days | #2 | |
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turboshaft (0)
Active User Posts: 1,958 Registered: Apr 01, '08 |
They are the result of compressed video files being used on DVDs (and in other video formats as well), particularly from older files that have been copied from one source to another. The problem is that DVDs use a lossy file format for their videos--raw, uncompressed video files are too enormous to be practical--and errors can show up from compression of the original files into the final MPEG-2s being used for the DVDs. This can happen in JPEG images as well, especially after the file has been opened and closed numerous times (uncompressed and then compressed again), the end result is a more pixelated looking image. (Wikipedia has an entry on compression artifacts too.) "It's incredibly obvious, isn't it? A foreign substance is introduced into our precious bodily fluids without the knowledge of the individual. Certainly without any choice. That's the way your hardcore Commie works." - Gen. Jack D. Rippper, Dr. Stranglove | |
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| 03-05-10 03:00pm - 5406 days | #3 | |
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messmer (0)
Disabled User Posts: 2,582 Registered: Sep 12, '07 Location: Canada |
Thanks, turboshaft. So compression artifact showing up could mean loss of clarity or pixelation. Is that right? | |
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| 03-05-10 03:05pm - 5406 days | #4 | |
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turboshaft (0)
Active User Posts: 1,958 Registered: Apr 01, '08 |
Yup. It's going to mean those special images and video of your favorite stars doing degrading acts are going to be, well, degraded, if you follow me. ;) "It's incredibly obvious, isn't it? A foreign substance is introduced into our precious bodily fluids without the knowledge of the individual. Certainly without any choice. That's the way your hardcore Commie works." - Gen. Jack D. Rippper, Dr. Stranglove | |
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| 03-05-10 03:22pm - 5406 days | #5 | |
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Drooler (0)
Disabled User  Posts: 1,831 Registered: Mar 11, '07 Location: USA |
What Turboshaft says is true! Once I realized that about jpegs, I understood why the images look so awful in the tours of some sites that have old, non-exclusive material. It's not just pixelation, with the tell-tale "halo" effect around a model's curvy edges, but loss of original color, too. The pics wind up looking "icky" after having been passed along through so many hands. I make it a point not to open a jpeg image file more than I need to, to save extras of real favorites (opened only as a "last resort"), and to back up copies of everything newly acquired on a separate volume. I suppose I could be even more extreme and anally retentive about it by saving them as lossless uncompressed TIFFs, but I'm too miserly with my hard drive space to do that! I wanted something new, so I left England for New England. | |
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| 03-05-10 03:46pm - 5406 days | #6 | |
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messmer (0)
Disabled User Posts: 2,582 Registered: Sep 12, '07 Location: Canada |
Good Heavens, Drooler, it's worse than I thought. I never knew that jpegs could deteriorate just by being looked at too often. Thanks for that bit of information. And I agree with you about TIFFS. Impossibly large files. | |
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| 03-05-10 03:47pm - 5406 days | #7 | |
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messmer (0)
Disabled User Posts: 2,582 Registered: Sep 12, '07 Location: Canada |
LOL. Gotcha! | |
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| 03-05-10 04:16pm - 5406 days | #8 | |
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Drooler (0)
Disabled User Posts: 1,831 Registered: Mar 11, '07 Location: USA |
It takes quite a lot of opening and closing a good quality jpeg to notice the effects of degradation. As a somewhat crude indicator, I figure that any jpeg under 200 px at 1200x800 was probably compressed too much from the beginning. But this is just a partial rule of thumb since file size also depends on the complexity of the image. Lots of colors and various shapes will make it bigger; a plain background containing light-skinned model with no elaborate tattoos will consume fewer kilobytes of hard drive space. Anyway, having become something of a "nut" about these matters, I often look at file sizes to help me get a sense of image quality. Since smaller images both "stretched" on the screen and reopened X-x's risk degradation, I go for larger pic sizes. I guess that helps explain why I'm such a critic of sites that don't go at least to 1600 px. BTW, other things that will hasten the degradation of a jpeg image is cropping it in a photo editor, or flipping or rotating it, and saving the result. So anyone who likes to doodle around with the photos ought to do it on TIFFs, not JPEGs. I wanted something new, so I left England for New England. | |
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| 03-05-10 05:54pm - 5406 days | #9 | |
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Reg Berkeley (0)
Active Webmaster Posts: 22 Registered: Apr 01, '07 Location: Las Vegas, NV |
Drooler's got some good stuff in there. But I would suggest the following correction -- JPEGs cannot degrade from opening and closing --- only from editing and resaving, thereby imposing additional compression. So view all your images until you guys are blue in the face...the quality won't be affected at all. Otherwise, all us webmasters would be constantly having to redo our static assets. | |
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| 03-05-10 07:59pm - 5406 days | #10 | |
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Wittyguy (0)
Active User  Posts: 1,138 Registered: Feb 04, '08 Location: Left Coast, USA |
x Edited on Apr 20, 2023, 02:06pm | |
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| 03-05-10 08:21pm - 5406 days | #11 | |
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Reg Berkeley (0)
Active Webmaster Posts: 22 Registered: Apr 01, '07 Location: Las Vegas, NV |
If compressed files could degrade, then the digital world would be screwed. For instance, all of your MP4s, WMVs or any compressed video would degrade thru repeated playback. Not to mention, compressed Winzip files, exe's, etc. This doesn't happen because the act of uncompressing the file for usage has no impact on the source file. It remains intact. It's the instance of re-saving where the issue is. For the common user, rotating a file image can cause a re-save. Even then, the effects are not substantial but can accrue over many times. The best analogy is a photocopier. What happens when you keep copying a copy? But if you are always viewing the original, you're fine. | |
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| 03-05-10 08:48pm - 5406 days | #12 | |
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slutty (0)
Active User Posts: 475 Registered: Mar 02, '09 Location: Pennsylvania |
Reg is correct, the only time degradation of an image file should happen is if you repeatedly copy or edit the file. I have had some issues with files showing some ill effects due to hard drive problems - although this is an issue with the hard drive, not with the file itself. The best course of action is to copy things as little as possible. Bunny Lebowski: I'll suck your cock for a thousand dollars. Brandt: Ah hahahahaha! Wonderful woman. We're all, we're all very fond of her. Very free-spirited. | |
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| 03-05-10 08:58pm - 5406 days | #13 | |
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Reg Berkeley (0)
Active Webmaster Posts: 22 Registered: Apr 01, '07 Location: Las Vegas, NV |
Copying shouldn't have ill effects either. Digital files consist of 0's and 1's. A digital file can't become less crisp or blurry without modification. It might as well turn black or pink. So as long as the file data hasn't changed, neither has the output. Oh, don't get conned into buying expensive HDMI or other digital cables. Degradation is mostly an analog concept. Digital is all or none. | |
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| 03-05-10 09:04pm - 5406 days | #14 | |
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anyonebutme (0)
Active User  Posts: 294 Registered: Aug 23, '09 |
This is due to other factors, pick your favorite out of these possibilities: (1) when upgraded to a better monitor, better clarity, revealing flaws in the source image that the previous monitor did not show (2) since bandwidth is faster & cheaper, sites are putting out higher quality photos than ever before, after getting used to today's quality, yesterday's doesn't look as hot as it used to (3) you're memory is fading. There is sufficient tolerance built into digital file storage that you are not experiencing actual degradation of the file. | |
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| 03-05-10 09:07pm - 5406 days | #15 | |
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anyonebutme (0)
Active User Posts: 294 Registered: Aug 23, '09 |
Compression artifacts in jpegs usually are best seen running the lengths of edges in the image and making large areas of a solid color fuzzy. Artifacts in mpeg videos usually take the shape of a block usually around the edges in the image. Here is an image from even a Blu-ray with compression artifacts (copy & paste the link) http://www.pics-hosting.com/files/yafqp1o08knzm3l4jnoq.png Edited on Mar 05, 2010, 09:12pm | |
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| 03-05-10 10:04pm - 5405 days | #16 | |
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turboshaft (0)
Active User Posts: 1,958 Registered: Apr 01, '08 |
D'oh! You're right, my mistake. It's from opening, editing, and then saving, not opening and closing alone, that ruins the files. This one little slip of the tongue (uh, keyboard?) seems to have scared quite a few members. Sorry, guys! (Though be aware that editing and modifying your images and videos will still degrade them.) Do I get a Darwin award for this? "It's incredibly obvious, isn't it? A foreign substance is introduced into our precious bodily fluids without the knowledge of the individual. Certainly without any choice. That's the way your hardcore Commie works." - Gen. Jack D. Rippper, Dr. Stranglove | |
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| 03-07-10 04:09am - 5404 days | #17 | |
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Drooler (0)
Disabled User Posts: 1,831 Registered: Mar 11, '07 Location: USA |
Wow, that's a relief to hear. I thought the degradation (from repeated openings) would happen slowly, just an indiscernible bit at a time and that it might take 100's or more of openings and closings to have a noticeable effect. But what you say answers a question I've always had in the back of my mind, which is how to keep stuff from degrading from a server getting tons of hits by users. (But maybe that's another matter, and the process continues to mystify me.) I'd gotten this bit of information, and now some misinformation, from my reading of a "computer corner" kind of article a few years ago in the Wall Street Journal. I must have misread something in it. So fine. And suppose that I've also been misreading their constant messages against financial regulation as being completely for the good of all, too. Whew. Well, that's a relief. I was starting to mistrust them. BTW, I've got a "rider" question What's a .BridgeSort file supposed to do? I get them sometimes from extracted zips of photo galleries. I toss them out 'cause I don't think I need them for anything, but what are they doing there in the first place? I wanted something new, so I left England for New England. Edited on Mar 07, 2010, 04:16am | |
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| 03-07-10 04:19am - 5404 days | #18 | |
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Bletch (0)
Active User Posts: 9 Registered: Sep 14, '07 Location: UK |
Thank God! I nearly died when I read your opening+closing photos=drop in quality reply!! | |
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| 03-07-10 08:38am - 5404 days | #19 | |
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badandy400 (0)
Active User  Posts: 869 Registered: Mar 02, '08 Location: ohio |
Wittyguy All the reasons Justme said are true, but i will expand one of them. The reason your older pictures are not looking so hot now is because you are now comparing them to something of much higher quality. When you first downloaded them they looked great because that was the best you may have seen. Now you have seen stuff that is much better. Kinda like your first car. You always remember your first car being this super fast beast that handles like a race car, until you years later you drive a car like it again and suddenly you realize how much it sucked! It is all relative. The point of digital media is that a 1 is always a 1 and a 0 is always a 0. There is no room for confusion. During analog this was not the case. There is a reason they use the term "analog" and it is because analog is like anally taking a log. With analog there is loss during playback and transmission, as well as loss due to age and use. Go to Lowes and look at all those paint color tabs. Notice how hard it is to tell some of them apart, but as you go down the different shards of green you begin to notice a difference. Analog can lose a little o the exact color. Also analog is like washing a shirt all the time in that it can ware out and lose integrity. Just like the color design on the shirt and all politicians. Bottom line. I would not have 30 TB of porn if I though it was going to degrade. So do not worry about losing quality of that video of a midget taking it anally from a horse that you love showing to your friends. It is look just the same and disgusting in 20 years when you show it off in the senior center as it does now. "For example, badandy400 has taken it upon himself to become the one man Library of Congress for porn with a collection that surely will be in Guinness Book of World Records some day." ~Toadsith~ PU Interview | |
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| 03-07-10 08:48am - 5404 days | #20 | |
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messmer (0)
Disabled User Posts: 2,582 Registered: Sep 12, '07 Location: Canada |
Thanks, Reg. That's good to know. | |
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| 03-07-10 09:00am - 5404 days | #21 | |
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messmer (0)
Disabled User Posts: 2,582 Registered: Sep 12, '07 Location: Canada |
Thanks, guys, for all those enlightening posts. I really enjoyed gaining a bit of additional knowledge as well as peace of mind! | |
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| 03-07-10 12:00pm - 5404 days | #22 | |
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turboshaft (0)
Active User Posts: 1,958 Registered: Apr 01, '08 |
Assuming that's still shocking in 20 years. Just imagine: "Oh, midget-horse anal--that's so last year!" :0 (Sigh, why do so many threads degenerate this perversely this quickly?!) "It's incredibly obvious, isn't it? A foreign substance is introduced into our precious bodily fluids without the knowledge of the individual. Certainly without any choice. That's the way your hardcore Commie works." - Gen. Jack D. Rippper, Dr. Stranglove | |
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| 03-07-10 01:06pm - 5404 days | #23 | |
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exotics4me (0)
Active User  Posts: 664 Registered: Jan 12, '07 Location: USA |
Messmer, you of all PUs should know "compression artifacts" occurs when we put a BBW granny in a bikini! I think they're just trying to confuse us like when a restaurant says they have burgers with under 20 grams of fat...if you leave the cheese, meat and sauce off, in turn, eating a salad on a bun! My first time I jacked off, I thought I'd invented it. I looked down at my sloppy handful of junk and thought, This is going to make me rich. - Chuck Palahniuk | |
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| 03-07-10 06:22pm - 5404 days | #24 | |
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messmer (0)
Disabled User Posts: 2,582 Registered: Sep 12, '07 Location: Canada |
Thanks for setting me straight on that one, exotics, all those others with their techno babble threw me off completely. I got all kinds of compression artifacted grannies on my hard drive, so next time some technically challenged newbie comes along and wants to know about the subject I can send him some samples! :-) | |
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| 03-08-10 12:00pm - 5403 days | #25 | |
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Wittyguy (0)
Active User Posts: 1,138 Registered: Feb 04, '08 Location: Left Coast, USA |
x Edited on Apr 20, 2023, 02:07pm | |
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