Re: PTP read-out from Fuji X-T100 extremely slow

On Thu, Jul 19, 2018 at 6:02 PM Marcus Meissner <[email protected]>
wrote:

> Hi,
>
> On Thu, Jul 19, 2018 at 04:37:41PM +0200, Thomas A wrote:
> > Hi,
> >
> > I found that listing files or just trying to pull one file from my
> Fujifilm
> > X-T100 using gphoto2 takes a very long time. (The same is true for
> whatever
> > backend Gnome uses - I did notice it was faster when there were fewer
> > images on the memory card of the camera).
>
> (From your debuglogfile you seem to have 1430 images in just one
> directory.)
>
> > I tried with both -L, to list all files, and --get-file=1. In both cases,
> > gphoto2 seems to go through the info for each file (object?) (To get
> > filenames?) and each read-out takes about 200ms. (Logs at [1]. Also tried
> > with gphoto2 2.5.15 / libgphoto2 2.5.16 on another computer)
> >
> > Is there any way to avoid these reads? I guess they are needed to map
> > filename to object?
>
> It is hard. We are doing the basic PTP directory retrieval, which should
> be used by almost all PTP applications, so all of them will likely
> be similar slow.
>
> We have on-demand retrieval, but it always needs to pull full directories,
> so this is is not useful in "all in one directory" scenarios.
>
> > Is there a 200ms wait performed by gphoto or is it my camera?
>
> This is the camera taking so long, not libgphoto2.
>
> > I tried searching for the problem. The closest I got is that the Fuji
> > PTP/IP protocol does not have unique object IDs [2]. Going by how
> > consecutive the numbering in the debug output is, this might be true for
> > PTP over USB as well?
>
> The objectids should be considered opaque, so we cannot and should not
> guess them.
>
> I think what happens is that the camera tries to access every file
> individually on the GetObjectInfo call, and due to the 1400 files
> it just takes long.
>
> I see, darn.


> > What I ultimately like to do is pulling a number of images (not all) from
> > the camera within a number of seconds. Getting previews is not necessary.
> > If necessary, I could resort to some kind of cache file and not delete
> > images from the camera (to avoid object remapping, if the non-uniqueness
> is
> > true).
> >
> > (In the long term I was thinking of only extracting images with a certain
> > "star" rating in the Exif data)
>
> Does the camera have a menu setting where it can create a new directory
> every
> 100 images? This would help the ondemand loading to make this quicker.
>

I have looked through the menus and the manual and I cannot find such an
option. I believe I read somewhere that it will create a new directory
every thousand photo.. (I believe I can have 1400 files due to shooting in
raw+jpeg mode, which creates two files for every photo.)

I found this disheartening line in the manual:
"If a memory card containing a large number of images is inserted, there
may be a delay before the software starts and you may be unable to import
or save images. Use a memory card reader to transfer pictures."


>
> Or a faster SD card?
>
> I looks like that, or a card reader, might be my only options. But I will
see if I can try the Fuji software out on a Windows computer and see what
happens.

Thanks for the informative answer!

//Thomas

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