"Former" function in display cmd doesn't work as expected

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jes
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"Former" function in display cmd doesn't work as expected

Post by jes »

When using the "former" function in either the "commands", or "shortcuts" menu in display, it doesn't work in a circular fashion, as I expect it to (or at least it doesn't work like the "next" function does). I see this on an older version (the one I care about - 6.5.4-7), as well as the latest (6.7.6-9). This is on CentOS 6.2 - x86_64.

My invocation is like the following:

display image1.jpg image2.jpg image3.jpg

Using 6.7.6-9, On startup, using the next function cycles through the images from image1 to image2 to image3, then back around to image1, and so on in a circular manner. However when on image1, the former function will not loop back around to image3. The former function *does* work on image2 (goes back to image1), and image3 (goes back to image2). But it won't loop back around circularly when it hits the first image, it just stays on image1.

FYI, I get a slightly different behavior on 6.5.4-7. The former function will work *one time* when display is first started, going from image1 to image3 (and so on, through image2 and back to image1). However after that first successful use, it will not work again on image1, and just stays on that image.

For grins, I also tried on 32 bit Windows, and I get the same behavior as described for 6.7.6-9 above, so seems to be OS/arch independent.

I'm taking a look at the code, but not terribly familiar with it, so I suspect a developer that's worked on it a lot will find it much faster :). If I do figure it out, I'll post back here. If a fix is found, I'd like to have a patch so I can backport to 6.5.4, as I need to stick with that version for my use case.

Thanks,
James
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anthony
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Re: "Former" function in display cmd doesn't work as expecte

Post by anthony »

I would say check -loop and -delay attributes, but you are using JPG which does not have them.

I also noticed errors in "display" for pipelined images, when you reach the end, but have not been too concerned with them.
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
https://imagemagick.org/Usage/
jes
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Re: "Former" function in display cmd doesn't work as expecte

Post by jes »

anthony wrote:I would say check -loop and -delay attributes, but you are using JPG which does not have them.

I also noticed errors in "display" for pipelined images, when you reach the end, but have not been too concerned with them.
For version 6.7.6-9, -delay does work properly. For version 6.7.6-9, -loop does not, it just sits on the first image indefinitely.

For version 6.5.4-7, the delay option doesn't work as expected, the image1 is opened, then after 3 seconds, the display program exists (with 0 error status). For version 6.5.4-7, -loop does the same as latest, it just sits on the first image and does not loop. I tried all of these with PNG files, and it has the same results.
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