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18

In short, Facebook is converting your image to the JPEG/JPG format (Join Photographic Experts Group). There seems to be no current way to upload images to use as a profile picture or to your photo album which Facebook will not convert to JPEG. ...a commonly used method of lossy compression for digital photography (image). The degree of compression can ...


8

Ten years ago, this would have been a great question. But in 2011, unless you are sure that a high percentage of site visitors will be on dial-up or similar low-bandwidth connections, the effort put into selective compression doesn't produce enough value to be worth it. The differences in quality and file size are so minimal, and broadband connections so ...


6

Here is an article on exactly your problem. Been having this problem as well. Hope this helps! Facebook uses a low quality jpg compression so any solid colors end up looking heavily pixelated. Solution is to add images at double the size with noise.


5

Having the same problem with a white text on a solid red background. My solution was to replace the solid red by a gradient of to reds. Afterwards I also added a Noise filter (or grain filter (7) in the filter gallery) in Photoshop. The improvement was very noticeable and the result was perfect. In attachment you can see the original and the finished result. ...


5

Everything @Scott said is true but for better understanding of the WHY and even how come RED seems to look worse, I direct you to this information (emphasis mine and edited for flow) JPEG ... is designed for compressing either full-color or gray-scale images of natural, real-world scenes [and] is a lossy compression algorithm... JPEGs are best ...


4

JPEGmini is pretty good at recompressing JPEGs to the lowest still-good quality. They claim to have a better model to predict which lossy changes are imperceptible to the human eye. This combined with ImageOptim (with jpegrescan in the latest version) gives the most efficient JPEG compression I'm aware of.


4

The one I like is called pngnq. It gives pretty good dithering, and one really really nice feature is that it lets you preserve the 8-bit alpha channel rather than quantising it to 1-bit (remember the bad ol' days of GIF?). It's command-line only, but if you don't mind that, it'll be a handy tool in your arsenal. You can choose to dither or not, of course ...


4

There were some good answers to this png compression question on SU. One or more of those might well fit the bill. Irfanview has excellent png support in its PNGOUT plug-in, and it's free for non-commercial use. It's been a while since I played with it, but iirc it did include lossy (color table) compression. That said, I'm fairly certain png output in ...


4

I'm betting that the photo of the girl is killing your size right now. To test that, remove her frame and replace it with one of the other frames of your animation. I'll bet the size drops quite a bit. Animated GIFs are best kept small by keeping their color pallets limited, and avoiding continuous tone graphics (photos, gradients, opacity shifts, etc.). ...


4

I don't work for Google so I can't speak to their method of sizing & compressing the images, but your image is very noisy which means that any modifications will significantly alter the sharpness of the textures you're using. Noting that their guidelines warn that your graphic "will be downsized to mini or micro", and even in a desktop browser the art ...


4

It's not about image compression but rather the number of HTTP-requests. Sprite sheets are a common developer technique nowadays. You can read an overview of the technique and its benefits here: http://css-tricks.com/css-sprites/


4

JPG is a lossy compression method. This means every time you save a jpg image data is thrown away in order to save file size (kb). It is important to realize that this loss of data happens each and every time you save a jpg. So if you open a jpg, then save it as a jpg you have thrown away more image data. It is in areas where the data loss has occurred that ...


3

I ended up using ImageOptim: http://imageoptim.com/ What it is is a wrapper around several different PNG optimization tools. It comes with OptiPNG, PNGCrush, AdvPNG, PNGout and a few other's you can add-on. The idea is that it picks the best tool for the particular PNG. It's not perfect in that it's still mostly automatic, so I can't fine tune more ...


3

My approach would be to use Select > Color Range: Eyedropper a clean area of the yellow to make it the foreground color. Be sure to set the sampling to 3x3 or 5x5, not single pixel. Choose Select > Color Range and click the "+" icon in the dialog. Work with the image until all the icon pixels are selected but none of the background (should be easy). ...


3

No, GIF for static images is a waste of bandwith. PNG can almost always be much smaller than GIF GIF has very poor compression algorithm, but has smaller header. PNG has few bytes more of overhead for extensible metadata, but has superior compression algorithm. So the larger the image, the bigger advantage PNG has. Basically only images like 1x1 spacer ...


3

All it really takes is a Levels, Curves, or Brightness adjustment. Almost any free or paid raster editing application has the capacity to raise the white point and lower the black point. This would, in turn, remove the grey, brighten the white, and darken the black. Images don't customarily "end up" like that without some serious alteration somewhere such ...


2

PNG is similar to GIF in many ways but even better in others. It is lossless like GIF but supports 8 and 24 bit color, unlike GIF which only supports 8. PNG supports one-color and alpha transparency, whereas GIF only supports one-color transparency. PNG uses various compression filters to minimize overall image size and can apply different filters on a ...


2

If this image is representative of your other images, with large, flat areas of color, then a simple color quantize can give a good result. In the sample images there are only three intended colors: two shades of grey, and yellow. Open the image in Photoshop, and choose Image > Mode > Indexed Color Set: Colors: 3 Forced: None Transparency: Unchecked ...


2

More tools: PNGOut Yahoo SmushIt (online) For me PNGOut seems to be the best, but in a few cases SmushIt produced lower sized images. OptiPNG produced larger files than both. There's also Google Page Speed, which tells you which images could be optimized...


2

I'm not familiar with paint.net specifically, but if you see a sharp image in the editor and it's blurry after export then it is being blurred by the program, not compression. Compression doesn't create blur, but one of the ways that a program can improve the jpeg compression ratio of an image is to give it a slight blur. In Photoshop, for example, there is ...


2

JPG is a lossy scheme. There will always be image degradation when saving as a jpg. If you started with a jpg, then save to a jpg things get even worse, fast. If a jpg set on maximum quality is not yielding the results you wish, then chances are there is no solution other than to live with the quality you are getting if the image must be a jpg. You might ...


2

I've found 3 different methods for lossy PNG (lossy averaging filter, vector quantization, median cut posterization) and implemented them in ImageAlpha. That's a Mac application, but tools for individual techniques are available for other platforms. Description and examples: http://pngmini.com/lossypng.html


2

Lately I've been using ImageOptim and ImageAlpha with very good results. ImageOptim is very good at optimizing and compressing GIF/JPEG/PNG and I'm using ImageAlpha to convert most of my images to PNG with good results: most of the times I get PNG files (full color) that are smaller than GIFs (50-60%), with very little quality loss. It even has an option ...


2

Various possible reasons: you are re-saving the images at a lower resolution. fewer pixels = less data = smaller file size your camera is likely saving JPGs with minimal compression. Your desktop software is using a higher level of JPG compression. Even if your software is using the SAME compression as your camera, each time you re-save a JPG, you lose ...


2

Google Play Store wants PNG24 not PNG8 "JPEG or 24-bit PNG (no alpha)" https://support.google.com/googleplay/android-developer/answer/1078870?hl=en auto formatting from PNG8 to 24 can cause issues like that. Try saving as PNG24 :D


2

You can't. When output from Photoshop's "Save for Web" feature, PNG-8 uses indexed transparency, like a GIF. You can get close by setting the Matte color to a similar color to the background your graphic will be on, but it won't be an actual Alpha-Transparency output. (You will still see the halo of anti-aliased pixels if you put the graphic on a background ...


2

There are a few ways to reduce the size of a TTF file, but most of them require that you know the consequences, since they are lossy. Firstly, you can subset the font, which means to remove any glyphs (character images) that you don't need. If you have a font that covers several languages and you only need to support one language, then this can be for ...


2

I'm not sure this directly answers your question, but since @AdamSchuld requested more detail ... Sprite sheets are good Sprite sheets have been around a long time and they are a wonderful tool. They can dramatically reduce the number of server requests for very small images. However, there is still a server request involved and it may not be necessary. ...


2

This could be achieved by using the function "File>Save for Web..." In the upper right corner you can select a preset and the file type. If you select JPEG and go with the settings in the picture above, you will get a small resolution picture with the same dimensions. You can play around with the settings and in the bottom left corner you can see the ...


1

The answer is obviously compression. An typical camera image is 3 long strings of numbers (between 0 and 255), one string for Red, one string for Green, and one string for Blue. The number is the brightness value for an individual pixel. The length of each string is the pixel width of the image mulitplied by the pixel height of the image. A byte is a unit ...



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