garygraphy Posted March 9, 2017 Share #1 Posted March 9, 2017 Advertisement (gone after registration) Understand that the M10 DNG file has a full sized embedded JPG within. Any ideas of how to extract that? Link to post Share on other sites More sharing options...
Advertisement Posted March 9, 2017 Posted March 9, 2017 Hi garygraphy, Take a look here Extract embedded JPG from DNG. I'm sure you'll find what you were looking for!
jaapv Posted March 9, 2017 Share #2 Posted March 9, 2017 Why should you want to, it is not much more than a thumbnail? Better shoot DNG+JPG. Link to post Share on other sites More sharing options...
luigi bertolotti Posted March 9, 2017 Share #3 Posted March 9, 2017 Time ago, for my curiosity, did download and read the complete specs of the DNG file (being an "open" standard, one can find them in the Adobe ecosystem) ... indeed, I seem to remember that (apart the "thumbnail") it anyway has inside, somewhere, also a std jpeg full res... but of course it would be not easy to extract a usable jpg file from... a very deep-level binary file manipulation program which, during development, can deserve any kind of surprise... don't see the reason to embark in such job, apart enjoiying a fine exercise of programming (but in this sense it would be more fun/interesting to write a program to extract YOUR OWN jpg from the native DNG data...playing with color tables etc... just to compare it with the std DNG+JPG output ) Link to post Share on other sites More sharing options...
digitalfx Posted March 9, 2017 Share #4 Posted March 9, 2017 or just make a JPG from the DNG...On a mac you can do this from Preview in one step, you can also batch multiple images. Link to post Share on other sites More sharing options...
ramarren Posted March 9, 2017 Share #5 Posted March 9, 2017 Get EXIFtool. Run from a command line "exiftool -s -s {filename}.dng > {filename}_EXIF.txt" In the .txt file you just made, you'll see the appropriate section of the DNG file that contains the preview JPEG data and the command required to extract that preview JPEG data into a file. Link to post Share on other sites More sharing options...
Guest Posted March 9, 2017 Share #6 Posted March 9, 2017 Get EXIFtool. Run from a command line "exiftool -s -s {filename}.dng > {filename}_EXIF.txt" In the .txt file you just made, you'll see the appropriate section of the DNG file that contains the preview JPEG data and the command required to extract that preview JPEG data into a file. Useful tool in many ways. Link to post Share on other sites More sharing options...
01af Posted March 9, 2017 Share #7 Posted March 9, 2017 Advertisement (gone after registration) The DNG files from the Leica M10 include two JPEG preview images, a thumbnail named "JpgFromRaw" (160 × 120 pixels) and a medium-sized one named "PreviewImage" (1440 × 960 pixels). As far as I can tell, a full-sized JPEG image is not included. To extract, use exiftool -b -JpgFromRaw {filename}.DNG >{filename}.JPG or exiftool -b -PreviewImage {filename}.DNG >{filename}.JPG Link to post Share on other sites More sharing options...
jdlaing Posted March 9, 2017 Share #8 Posted March 9, 2017 The DNG files from the Leica M10 include two JPEG preview images, a thumbnail named "JpgFromRaw" (160 × 120 pixels) and a medium-sized one named "PreviewImage" (1440 × 960 pixels). As far as I can tell, a full-sized JPEG image is not included. To extract, use exiftool -b -JpgFromRaw {filename}.DNG >{filename}.JPG or exiftool -b -PreviewImage {filename}.DNG >{filename}.JPG Correct. It is not included unless you set the camera for RAW + Jpeg. Link to post Share on other sites More sharing options...
scott kirkpatrick Posted March 9, 2017 Share #9 Posted March 9, 2017 Sandy McGuffog put up a simple utility called DNG Cleaner on the Apple store which 1. Removes any XMP information, including Lightroom/ACR settings 2. Removes any Lightroom/ACR profile information. (AKA non-embedded profiles) 3. Optionally removes any opcodes (e.g. for distortion correction, which LightRoom applies automatically 4. Deletes any existing preview images, and regenerates a “standard” set 5. Optionally compresses the image data. and claims that he sees shrinkages on the order of 3MB per file from steps 1-4. I have seen full sized jpegs incorporated, but since I don't have an M10 myself, I don't know if this was a side effect of outputting DNG + JPG. I presume it is there to allow checking focus and sharpness after the shot is taken. Link to post Share on other sites More sharing options...
sandymc Posted March 9, 2017 Share #10 Posted March 9, 2017 Technically, what the M10 DNG looks like is as below. So you need an app that can can extract IFD0, subIFD 1 ----------------------------------------- IFD 0: Offset = 12, Entries = 49 NewSubFileType: Main Image ImageWidth: 5984 ImageLength: 3992 SubIFD 1: Offset = 918, Entries = 12 NewSubFileType: Preview Image ImageWidth: 5952 ImageLength: 3968 SubIFD 2: Offset = 768, Entries = 12 NewSubFileType: Preview Image ImageWidth: 1440 ImageLength: 960 SubIFD 3: Offset = 618, Entries = 12 NewSubFileType: Preview Image ImageWidth: 160 ImageLength: 120 Link to post Share on other sites More sharing options...
luigi bertolotti Posted March 9, 2017 Share #11 Posted March 9, 2017 Ah...being an old-former-programmer I considered only the Do-It-Yourself way "times are changing"... you find an app for anything you like... Link to post Share on other sites More sharing options...
luigi bertolotti Posted March 9, 2017 Share #12 Posted March 9, 2017 The DNG files from the Leica M10 include two JPEG preview images... Hmmm... this (as far as I remember) is just you find from a quick analisys... I don't remember well (made my analisys of the DNG specs years ago.. at "M8 times") but the thumbnail data derived from a first jpg processing which was somewhere embedded within the DNG derived data... and you could find (didn'try, indeed) the way to extract them to obtain a full res jpg... (but... it was 2008 or 2009... haven't even saved my exercises...) Link to post Share on other sites More sharing options...
scott kirkpatrick Posted March 10, 2017 Share #13 Posted March 10, 2017 The M10 DNGs differ in quite a few ways from the M9 and M240's. To start with, they are created with DNG protocol 1.4 which allows a few more embedded types of information that any program should be able to read. There are also embedded Adobe templates, initialized with null or no values, that provide a framework for Lightroom users to insert their development profiles in the raw file. I suppose this replaces "sidecar" files, but since I am not a LR user, it is wasted on me. scott Link to post Share on other sites More sharing options...
pico Posted March 10, 2017 Share #14 Posted March 10, 2017 Oi, Kirkpatrick! Are you trying to suck the bit-twiddlers away from making pictures? Oh! Okay. Proceed. Link to post Share on other sites More sharing options...
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