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17

Going from JPG (which is a lossy format) to any lossless one (like PNG) does not. Going from any format to a lossy one, yes, including JPG to JPG. It could be too little to notice, and using the same compression ratio loses a lot less on the second saving than on the first one, but yes, it is cumulative. But beware... Some image formats store more ...


11

You can probably do this by creating an action and then batch processing: Create the action with an open file in photoshop start recording do File > Save As > and set file type to PNG or use File > Save for Web if you need to resize or make other modifications click Save stop recording and save action as "Save As PNG" (there may also be some built in ...


10

The RAW formats store, well, the raw sensor data from the camera with information on how to decode that for image processors such as Adobe Camera Raw or similar. In that sense, the RAW format is not an image, you have to apply demosaicing algorithms to interpret the sensor data into a coherent image for display. Beyond the Adobe attempt to convince everyone ...


9

Edit: This answer is out of date. As of July 2017, PNG supports EXIF chunks. exiftool can edit PNG chunks, but Windows explorer apparently still does not support PNG chunks. See comments by posfan12 and lukeuser below. TL;DR: PNG doesn't formerly didn't support EXIF metadata (when the question was asked) While PNG can embed metadata chunks, standard ...


9

For photographic images and when a not too high level of compression is used, the loss of quality in the JPEG format is negligible and invisible. You'll pretty much only be able to notice it by directly comparing individual pixels around sharp edges or in very smooth color gradients. This is why JPEG is so popular. If it always resulted in noticeable loss ...


8

Yes, PNG is theoretically better than JPEG in preserving the ultimate image quality, but in practice this is the kind of exactness we don't really see, especially in print, where the physical properties of the paper and ink technology limits what can be achieved. For convenience, just stick with the universally accepted JPEG and be happy with smaller file ...


7

The problem is that the metadata that Windows uses as the "Date Taken" varies by file. For example, for a JPG, Windows will use Exif:DateTimeOriginal if it exists, followed by XMP:DateTimeOriginal, followed by CreateDate, followed by FileCreateDate (the system file create date). (Off topic, if anyone has a link that lists details of all the types of files ...


7

No. PNG does not support EXIF. In fact, lack of a standardized metadata block is one of its big disadvantages for photography. If you need a lossless format which preserves (very-similar-to-EXIF, since it's the basis for EXIF) metadata, try TIFF. The downside, though, is that TIFF rendering support is not as widespread as that for PNG (for web applications ...


6

If you are asking about "print shops" in the sense of printing brochures, and other primary text-based material, then yes, I can understand that they only accept PDF: they want the most precise layout possible for text-based layouts (so-called "camera-ready": they can feed your PDF straight into their workflow, generating offset plates from the pages you ...


4

To remove all the EXIF info from your photos you can use exiftool The command should looks like: exiftool -all= coolphoto_16x16_6color.png


4

It's actually a mislabelled TIFF file. The conversion with GIMP seems to have resulted in a darker outline, not sure why, but try using a different conversion software, like image magick or IrfanView.


4

TweakPNG is a free software that can edit PNG metadata (Windows only).


3

Avoid PNG-8 for photo images (it is for graphics with few colors), but PNG-24 is very good choice for photo images. Better than JPG for quality, but will be a much larger file than JPG. PNG always compresses, and compresses reasonably well, smaller than TIF LZW, but not nearly as small as JPG. Both PNG and TIF LZW are lossless compression, meaning there is ...


3

You can't. Not with a lossless format like PNG. Image compression depends on the amount of information in an image, ie. the detail present. A square of a solid blue contains little information and can thus be described simply (as i did here). If i were to describe the Mona Lisa to you, i'd need a bit more than five words. Software compression works the ...


3

In addition to what the other have said, PNGs are horribly inefficient at storing photos. Their compression scheme is designed to perform well when there are relatively few colors, large areas of the same color and/or exactly repeating patterns. A quick test with a random 18 MP photo yielded these results: Original RAW: 22 MB JPEG with 100% quality: 14 MB ...


3

ExifTool can edit PNG metadata. You can find the list of the supported tags here. Exiftool is a free command line tool, but there are GUI tools (listed on the ExifTool website) using the ExifTool engine.


3

You want to use ImageMagick, its free and open source. Get it from http://www.imagemagick.org/script/index.php Then use the "convert" function To resize a batch of photos, open a terminal window to the folder containing your photos and use the command: mogrify -resize 700x700 *.png


2

First off I am not sure if there is an easy way to create an invisible watermark in PSE without buying a Digimarc subscription. With that said there is a way to create an (almost) invisible watermark using the blue channel and layer styles but this is not possible in PSE. Here is a tutorial on how this is done in PS. (Maybe download the trial version of ...


2

I did some more tests and I think the issue is color space conversion. Here's the testing procedure I used with Photoshop CC 2014: Create a new file with 8-bit, Adobe RGB 1998 color space. Create a rainbow gradient. Save for Web as PNG; don't convert to sRGB. Place embedded the PNG file just saved. Change PNG layer blend mode to difference. There is a very ...


2

PNG metadata is poorly supported by most software, but it looks like in this case, Google has started supporting EXIF data in PNG, which it did not in my previous tests. If you write to the EXIF:DateTimeOriginal in a PNG, Google photos will correctly read the date/time, at least in my test. It also seemed to support other data written to the EXIF group, ...


2

You cannot just export a raw to TIFF, PNG or JPEG, you'll have to do some treatments, for a number of reasons. But you seem more interested in the differences between the different file formats. I'd stay away from TIFF, as there are just too many 'dialects' for that format, and in this context, it has no advantages over the other formats. For the choice ...


1

I pretty much agree with Rafael on the following points: Colorspace conversions will result in some losses (mainly rounding errors). Decreasing color depth loses color information. Transparency may be lost. Layers and effects may be lost. Metadata may not be preserved. (Even if a program doesn't remove any tags, most cannot help but to add something.) ...


1

For the following answer: when referring to a file that contains the contents of a disk image file we will use "IMG". When referring to a file that contains a picture in an actual visual image format, we will use "image". If the information in your question is taken at face value It appears to be mainly due to the limited resolution of the original image ...


1

The short answer is yes (unless you have a camera that can output PNG files (which, I believe, is very few)). The long answer is (in general) sort of. As mentioned in the comments, file conversion is, technically, a form of alteration and so, for the vast majority of photos, having a .PNG extension means that they has been altered. This does not mean that ...


1

They're really different formats to do very different jobs. PNG is intended to be a non patent-encumbered format for network use - it was not designed for photography and there are aspects of the design where this shows. Alpha Channel an extra colour channel for variable opacity ADAM7 interlacing for a quick preview or for the whole image not to be ...


1

RAW is greater than 8 bits and stores the actual sensor data rather than processed image data. RAW is actually generally losslessly compressed, or even sometimes lossy compressed. PNGs would actually be larger if uncompressed because they only hold the image data after processing, which means each pixel has 3 colors rather than 1, and is generally only 8 ...


1

If metadata is added to PNG files, such as keywords, it doesn't "stick" permanently. I found the only safe way was to use Bridge > Photoshop > Image processor and batch change the PNG to a JPEG, PSD, or TIFF file. I used tiff LZW to save space and even then it is a larger file than the png. I needed this to be able to add keywords and descriptions to pngs in ...


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