Compressing M10 DNG files

[wolan]

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Hi 

the DNG files coming out of the Leica are already (lossless) compressed?

To me it looks like they are not compressed, therefore the second question: it is possible to compress them after the fact using some utility that processes the files on the file system? Of course in a way that the editing software can process them.

Thank you

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[jdlaing]

4 minutes ago, wolan said:

Hi 

the DNG files coming out of the Leica are already (lossless) compressed?

To me it looks like they are not compressed, therefore the second question: it is possible to compress them after the fact using some utility that processes the files on the file system? Of course in a way that the editing software can process them.

Thank you

https://fstoppers.com/lightroom/save-67-percent-your-disk-space-lightrooms-dng-compression-253337
 

 

[jslabovitz]

From what I can see, the DNG files from the M10 are indeed compressed. I used some command-line utilities (‘file’ and ‘tiffinfo’) to examine a recent shot from my M10-D, and those both claimed the DNG was a TIFF file using JPEG compression.

I looked up what this really means, and it’s a little hard to find useful info. But I reckon what’s happening is the image is compressed using a process similar to a normal JPEG with ‘maximum’ quality specified. In other words, the image is *lossless* and compressed (as opposed to most JPEG files you find in the wild which are *lossy* and compressed).

Different compression algorithms can compress images in a way that makes for smaller data, but there’s always a trade-off between speed (needing to write the file fairly quickly on the camera), accuracy (lossy/lossless), and space (wanting the smallest file). It’s like the old adage: Good, fast, cheap — pick two. 😉

In theory, some tool could pull apart the DNG file, uncompress the image, and recompress it with an algorithm that was more space-efficient and yet still readable by, say, Lightroom. However, in my experience you’re not going to save much — perhaps 10% — so it’s unlikely to be worth it to take these steps.

As others here have pointed out, you’re more likely to save space by deleting unwanted photos than to find a ‘goldilocks’ compression algorithm.

[Good To Be Retired]

Hi 

the DNG files coming out of the Leica are already (lossless) compressed?

To me it looks like they are not compressed, therefore the second question: it is possible to compress them after the fact using some utility that processes the files on the file system? Of course in a way that the editing software can process them.

Thank you

 

Regarding whether the file is compressed, Leica Rumors published an interview with Leica people in 2017 that I suppose is still valid.

The raw file (DNG file) is smaller than the M 240, and do we have choice of the uncompressed RAW file?

Jesko: It is not available anymore. we decided to only to offer compressed file. Because we do know it is lossless. The performance of the camera is much better because the files are smaller. We figure out that most customers use uncompressed because they don’t trust the compressed, and as a result, they don’t use the full possibility of the camera. The quality of compressed and uncompressed is the same.

Read more: https://leicarumors.com/2017/01/29/leica-m10-interview-why-no-video-where-is-the-typ-label-compressed-dng-files-and-more.aspx/#ixzz6cq9cKNST

Edited November 4, 2020 by Good To Be Retired