Large images not correctly displayed about geeqie

[mowgli]

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I confirm that it happens in both directions.

More, when displayed at real size (1:1), only garbage is displayed, even in the zone < 32767. All other zoom factors display the image up to 32767, then white image.

Thumbnail is correctly displayed, so it seems to be related to display widget, not to file reading.

Original comment by: fma38

[mowgli]

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May be related to X maximum window size (which is 32767 pixels wide or tall).

From http://www.pygtk.org/pygtk2tutorial/sec-Layout.html:
"The Layout container is similar to the Fixed container except that it implements an infinite (where infinity is less than 2^32) scrolling area. The X window system has a limitation where windows can be at most 32767 pixels wide or tall. The Layout container gets around this limitation by doing some exotic stuff using window and bit gravities, so that you can have smooth scrolling even when you have many child widgets in your scrolling area."

Original comment by: zas_

[mowgli]

Perhaps a fix...

Original comment by: zas_

[mowgli]

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Frederic, please try this patch.
With it, i can display a 38000 pixels wide jpeg image.
Unsure if it is a correct fix, but please test.
File Added: pixbufrenderer_parent_class.patch

Original comment by: zas_

[mowgli]

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IMHO the most important limitation is inside gdk-pixbuf library. Max. pixbuf size that it can allocate is
widthheight3<INT_MAX, that is around 32768*21845, see source for gdk_pixbuf_new().

We can write a special image loader that reads image into multiple pixbufs. Pixbuf renderer can handle it (see source tiles) but it would need some adjustments in image.c and in other places, but that should be doable.

Original comment by: nadvornik

[mowgli]

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The patch doesn't solve the problem.

Original comment by: fma38

[mowgli]

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gdk_pixbuf_new() is using gsize type so the allocation limit is near 37800 x 37800 pixels.

BTW, in pixbuf-renderer.c, pixmap_calc_size() should return a gsize instead of int.

Original comment by: zas_

[mowgli]

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eog has the same problem.

Original comment by: nadvornik

[mowgli]

• labels: --> Image formats
• milestone: --> no target version

Original comment by: nadvornik

[mowgli]

The bug is in gdk-pixbuf, there has been a ticket upstream for 6 years : https://bugzilla.gnome.org/show\_bug.cgi?id=163090
I dig a little bit into it and proposed a workaround in the comments.

Original comment by: cyril42e

[caclark]

Probably fixed by #772