Problems converting tiffs to JPG on MacOS Catalina

[caveduck]

Hi,

New forum user here, though I've been using XnConvert for quite a while (BTW thanks for fixing dark mode!!).

I've hit a few new gremlins converting some scanned .tiff files to .jpg with 1.83 on a new 2020 MacBook Pro running Catalina. The .tiffs are good sized (4Kx3K, 35-38MB) and I am doing a 100% quality conversion. They are from an Epson 4990 scanner using Image Capture on the Mac. Here are the issues:

1) [bug] With the jpg "subsampling factor" at default, many images get a big diagonal shear. However, if I set it to "best quality", the problem goes away.

2) [bug] I have at least one .tiff that kills XnConvert instantly when you add it to the Input tab (before I even try to convert it); you get the "XnConvert has quit unexpectedly" system dialog. It looks like this happens while XnConvert is generating the preview thumbnails for the input tab. I'm trying to isolate the specific file from the batch but that's tedious, though I imagine you'll want the file. I can view them all in Mac Preview so it doesn't seem fundamentally corrupt.

3) [feature] If I add metadata tags with Nikon ViewNx-i, the metadata is not copied over into the .jpg though "Preserve metadata" is on. I'm basically sure this happens because ViewNx-i now stores metadata in a sidecar file inside ./NKSC_PARAM/ and XnConvert doesn't look there. Older versions of ViewNx embedded the metadata. I have other reasons for wanting to dump ViewNx-i out of my workflow (horrible performance on network drives) but I thought I should still report this.

Regards,
Dave Cook

[caveduck]

Some more information on 2) above

The crash is sporadic and it does not actually seem to be a specific file - I have gotten it to happen maybe half a dozen times, but it won't die if I'm only dropping a single file.

During the investigation I've found some more frequent and highly repeatable anomalies in thumbnail generation. If I drop 10-30 files on it, often the very first one (top left in the list) does not get a thumbnail generated. But if I afterward drop one or a few more files, it will trigger generation of the missing thumbnail.

If I drop 30 files on the window and then grab the vertical scroll bar control and start moving it (or just mouse-scroll), it will reliably cause many of the thumbnails to not get generated, as many as 90% with aggressive mouse-scrolling. They will not fill in when I stop scrolling. Dropping additional files then will trigger most or all of the missing thumbnails to get generated, but sometimes one will still be missing.

The missing-thumbnail behavior is the same whether I add files by drag-n-drop or the "Add files..." button.

[xnview]

1) [bug] With the jpg "subsampling factor" at default, many images get a big diagonal shear. However, if I set it to "best quality", the problem goes away.

Could you send me the settings used, and sample file?

2) [bug] I have at least one .tiff that kills XnConvert instantly when you add it to the Input tab (before I even try to convert it); you get the "XnConvert has quit unexpectedly" system dialog. It looks like this happens while XnConvert is generating the preview thumbnails for the input tab. I'm trying to isolate the specific file from the batch but that's tedious, though I imagine you'll want the file. I can view them all in Mac Preview so it doesn't seem fundamentally corrupt.

could you send it to me?

3) [feature] If I add metadata tags with Nikon ViewNx-i, the metadata is not copied over into the .jpg though "Preserve metadata" is on. I'm basically sure this happens because ViewNx-i now stores metadata in a sidecar file inside ./NKSC_PARAM/ and XnConvert doesn't look there. Older versions of ViewNx embedded the metadata. I have other reasons for wanting to dump ViewNx-i out of my workflow (horrible performance on network drives) but I thought I should still report this.

i need a sample file please

[caveduck]

Hi Pierre,

For the Nikon files, I've attached a screenshot of what the directory looks like after adding metadata to a bunch of Nikon raw NEF files. Note that in the NKSC_PARAM folder there is a .nksc file for every NEF. A zip of one of these files is also attached. Nikon ViewNX-i puts all of the metadata in there, along with any image adjustments you make. (There are no image adjustments in my example file).

On the dropping-files-into-the-input-tab issue, please see my 2nd message for updated details. I've attached a screenshot of what typically happens when dropping a good number of files when it's set to "thumbnails" and the files are coming from a local file system - most of the time the first thumbnail never generates. Interestingly, this first-file problem usually does *not* happen when dropping files from a (slower) network file share. I've also included a screenshot with 9 missing thumbnails after dropping 33 .tiff files from a network drive and wiggling the scroll bar quite a bit. I also noticed tonight that this happens a lot more with the 40MB TIFF files than it does with similar sized NEFs.

The crash and shear problems stopped after a full system reboot. In the previous session I reported on, I had restarted XnConvert itself a number of times and those issues survived across the app restarts. I probably spent 3 hours last night trying to reproduce those, to no avail.

Regards,
Dave

[xnview]

See issue for current status and some details about thumbnails problem.