Corrupted RAW (NEF) file after transfer with RPD?


I’m a long time user of RPD and never had troubles when downloading RAW (NEF) file with this great program before.

Now, I’m on a Dell XPS 13 with a built-in micro SD Card reader, so I have to use a clunky set of adapters (micro-usb to regular SD card reader) to transfer pictures from my regular Nikon SD cards. With this far from perfect setup, I have experienced problems lately when transferring pictures with RPD (version 0.9.22 on Ubuntu 20.04): I get some corrupted RAW files (paired jpg’s are fine), i.e. when I try to display them with any RAW editor (darktable, gthumb, etc.), I only get a partial image (most of the frame is gray).

However, if I try to edit (develop) the RAW files (in darktable), it seems that all the content is available, so it may indicate that only the embedded jpg images within the RAW is corrupted/partially transfered.

Also, when I go back to the original RAW files on the SD card and transfer them with a file manager (i.e. Nautilus in GNOME), then they are displaying and editing fine.

So, at first sight (and I may be wrong of course…), it seems that RPD may be missing some bits of the RAW files when it tries to transfer them, considering that the problem does not occur with a “regular” file transfer with the file manager (Nautilus).

Is there anything I’m missing to solve this problem (apart from improving my SD card adapter setup…)? Is there a way to for RPD to double check for file integrity upon transfer?

I may file a bug report if necessary.

Thanks in advance for any help.

Upgrade to 0.9.24 and see if you can replicate the problem. The problem might be related to this issue.

@mlaverdiere I would appreciate an update on your findings. There is no issue more serious than file corruption. If you can replicate the problem, it could be caused by hardware or software. It’s important for the community of Rapid Photo Downloader users (and me as the developer) to know which is the case in the problem you are seeing.

I really truly don’t have time right now to go into details of why actual file verification is not an easy problem to solve. The only way I know of to truly be sure a file is copied correctly would be to copy it onto 3 different systems and then compare the results, taking the results of 2 of them when 1 differs. If all photo file formats had a checksum built into them, that would make life easier. Alas, they do not.

OK, I’ll do some testing and report back.

Here are the results of my testing with various transfers of 518 files/pictures (RAW+JPG pairs), for a total of 8,7 GB, with the same set of USB/SD card adapters reported above, on Ubuntu 20.04/Dell XPS 13 :

  • With RPD 0.9.22: 69 corrupted RAW files.

  • With RPD 0.9.24: 44 corrupted RAW files.

  • With a file manager (Nautilus), based on 2 transfers:
    - First test: 0 corrupted RAW files
    - Second test: 19 corrupted RAW files.

See here, an example of a corrupted RAW file with the corresponding JPG and the original good (not corrupted) RAW file: pCloud

I don’t have time right now to test further, but these results may suggest the following:

  • My hardware setup (bad combination of USB-C/SD card adapters) is probably the cause of the problem, not RPD. Maybe there is some kind of process interrupt going on during the transfer that is preventing all the bites to transfer…

  • I don’t know what are the technical difference between how RPD and a file manager like Nautilus proceed to files copying/transfer, but at first sight, it seems that RPD is less likely to prevent these kind of errors than Nautilus.

Hope this helps!

You can use the command journalctl on the command line to see output from the kernel regarding your hardware problem.

Rapid Photo Downloader uses standard Python library tools to copy files, whereas Nautilus uses Gnome’s GIO. GIO can be a bit slower, which might be why you’re seeing less failures with Nautilus.

If you may like to try plugging in your camera directly, assuming your hardware problem is not USB related.