Linking to images

[Tony]

I’m thinking about getting TapForms to make a database of a photograph collection.

The database itself would be to record things like shoot date and location, technical info on the stuff we shoot, and so on – all pretty straightforward.

What I’m not so sure about is this. Can I have a thumbnail of the image in the database, and also a link within the database to take me to the hi-res version of the image (stored elsewhere)? Is it possible to do that?

I’d be grateful for any help you can give.

[Brendan]

Hello Tony,

Tap Forms will automatically generate a thumbnail of the image for you. If you put your Photo field as the first field in the list of fields in a form, then it will display a thumbnail image next to the other fields in your form in list view.

Photos are stored externally to the app, but not in a user defined location. They’re stored in a different folder depending on whether or not you have iCloud sync enabled.

Without iCloud sync enabled, photos are stored here:

~/Library/Containers/com.tapforms.mac/Data/Documents

With iCloud sync enabled, photos are stored here:

~/Library/Mobile Documents/FXLPHZS84D~com~clickspace~tapforms/Documents

Thanks!

Brendan

[Tony]

Hello Brendan. I appreciate you responding to my post.

I’ve now downloaded the demo for OSX and played with it a little – and it looks excellent – so I can make practical sense of what you say.

A few more questions:

1. I tried to generate a thumbnail from a .psd file, but it wouldn’t work. I had no trouble with generating a thumbnail from other image files, including a .jpg, a .png, and a .tif. Is that correct, that TF can’t make thumbnails from .psd files?

2. Using different types of image files to generate thumbnails seems to vary the size of file that’s stored in Data/Documents/Photos. A 4.8MB .tif makes an 86KB thumbnail. A 1.3MB .png makes a 105KB thumbnail. A 1.2MB .jpg makes a 1.4MB (!) thumbnail. I’m trying to minimise what I store additionally in TF’s folders, as I have a large collection. Is there a simpler way to achieve that?

3. Using “add file alias” to link to an image file on my system still seems to put an image in TF’s Data/Documents/Share/Attachments folder. I thought the point of the alias method is simply to link to a file on my system, without duplicating it? Again, my intention is to add files to my storage as rarely as possible, so I wonder if I’m doing this correctly.

Thanks again,

Tony

[Brendan]

Hi Tony,

1. The Photo field type works really only with basic image files. It doesn’t really handle Photoshop files.

2. Did you select one of the scaling options for the Photo field or are you using “Original” as the photo size? Tap Forms generates a small thumbnail for displaying in the records list views, but that’s stored in the database itself, not on disk. The files you select are converted to JPEG files with a 90% quality factor before being saved to disk. This is so that the iPhone and iPad versions of Tap Forms can view them. If you want the files untouched, then use a File Attachment field.

3. Aliases can be pretty big. I think the operating system stores a thumbnail of the image inside an Alias file. It’s not JUST a link to the original file. I’ve done a lot of research on this issue and other developers have the same issue. Alias files are more than just links now. They’re actually bookmark files which contain more than just a pointer to the original file. The dumb part of this is you could have an alias to a 100 KB file, but the alias file itself takes up 1.4 MB of disk space. It’s an issue. But if you were linking to a 10 MB file, you might still only have a 1.4 MB alias file, so you save space in that kind of case.

Here’s a discussion about this issue on Apple’s public discussion forums:

https://discussions.apple.com/thread/3988292?tstart=0

Thanks!

Brendan

[Tony]

Thanks Brendan.

2. I did choose the smallest option.

3. Interesting. I’d not noticed that aliases were getting so big until now. It does rather seem to take away the point of them, doesn’t it.

Anyway, I had further tries with sym links and aliases of aliases, in all the combinations I could think of, and then a few more, but nothing makes any difference. Size clearly does make a difference in this case.

Oh well, looks like time to buy another remote drive dedicated to all this. It’s not as if storage space is expensive any more.

One more question: is it possible to rotate the thumbnail image? Ninety degrees would be helpful.

Tony

[Brendan]

Hi Tony,

There’s no rotate functions. But there is a bug currently which affects rotation. I have fixed it for the next update. If you use any of the scaling options, the image will be rotated. But if you use Original it should be ok.

Thanks,

Brendan

[Tony]

Ok, Brendan, that’s useful to know. And thanks again for your help with this stuff.

[Author]

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