Knowledge Base (Posts about images)

Crop screenshots to same window area

bgstack15 — Fri, 11 Oct 2024 12:46:00 GMT

I had problems getting exact screenshots of some work, and was merely able to get full desktop screenshots. So I needed to crop to just the relevant portion. In my case, I wanted an 800x600 picture, from my second monitor (first being the left monitor, and second being the right monitor), starting at 1920+560 pixels by 240 pixels.

for word in *png ; do convert "${word}" -crop 800x600+2480+240 foo/${word} ; done

Really small, and dumb, but I'll need this again someday.

References

Cropping Images using Command Line Tools Only - Ask Ubuntu

Make optionMenu with images in python tkinter

bgstack15 — Sat, 27 Apr 2024 12:45:24 GMT

Here is another fantastic trick in tkinter: get images on an optionmenu (drop down, or combobox).

files/2024/listings/demo-optionmenu-with-images.py (Source)

	`#!/usr/bin/env python3`
	`# Startdate: 2024-04-08-2 13:44`
	`# Purpose: demo of the cool features of tkstackrpms`
	`# Reference:`
	`# [python - Can I possibly put an image/label into an option box in Tkinter? - Stack Overflow](https://stackoverflow.com/questions/67334913/can-i-possibly-put-an-image-label-into-an-option-box-in-tkinter/67337760#67337760)`

	`# demo 1: optionmenu with images and text`
	`import tkinter as tk`
	`import tkstackrpms as stk`

	`class App(tk.Frame):`
	`def __init__(self, master):`
	`super().__init__(master)`
	`self.master.title("Demo of tkstackrpms features")`
	`imgicon = stk.get_scaled_icon("battery",24,"default", "","apps")`
	`self.master.tk.call("wm","iconphoto",self.master._w,imgicon)`
	`self.grid()`
	`self.options = ["Blue","Green","Yellow","Purple","Red"]`
	`# prepare set of images that corresponse to the options`
	`self.img_colors = []`
	`for i in self.options:`
	`t_image = tk.PhotoImage(width=16)`
	`t_image.put(i,to=(0,0,15,15))`
	`self.img_colors.append(t_image)`
	`self.opt_choice = tk.StringVar()`
	`self.opt_menu = tk.OptionMenu(self.master,self.opt_choice,*self.options)`
	`# indicatoron=False turns off the weird second-button item within the button.`
	`# minimize the padding so the box is not huge`
	`# takefocus allows navigation to this widget with Tab`
	`# compound means when an image is present, put it to the left of the text.`
	`self.opt_menu.config(indicatoron=False,padx=1,pady=1,takefocus=1,compound="left")`
	`self.opt_choice.set(self.options[0])`
	`self.opt_menu.grid(row=0,column=1)`
	`ow = self.opt_menu.nametowidget(self.opt_menu.menuname)`
	`x = 0`
	`for i in self.options:`
	`ow.entryconfigure(i,image=self.img_colors[x],compound="left")`
	`x += 1`
	`self.opt_choice.trace("w",self.set_selected_optmenu_entry)`
	`self.set_selected_optmenu_entry()`

	`def set_selected_optmenu_entry(self, arg1 = None, arg2 = None, arg3 = None):`
	`this_color = None`
	`x = 0`
	`for i in self.options:`
	`if self.opt_choice.get() == i:`
	`self.opt_menu.config(image=self.img_colors[x])`
	`break`
	`x += 1`

	`# main`
	`root = tk.Tk()`
	`app_tk = App(root)`
	`app_tk.mainloop()`

So you have an optionMenu widget, where each option has an image associated with it. We're using very basic samples here; any real-world use of this trick would have a more complex list of images and options.

You can even set the front label of it to have an image, so you can view the currently selected image without having to open the drop-down.

Poor man's html image gallery

bgstack15 — Thu, 06 Jul 2023 13:00:10 GMT

For a personal website for which I hand-roll the html code, I wrote a small shell image link+thumbnail generator script. I shouldn't be proud, but I am.

	`#!/bin/sh`
	`# Startdate: 2020-11-27 15:09`
	`INDIR=/mnt/public/www/images`
	`DIRPREFIX="images"`
	`THUMBNAIL_SIZE=300`
	`USE_THUMBNAILS=1`
	`if test -n "${USE_THUMBNAILS}" && test "${USE_THUMBNAILS}" = 1 ;`
	`then`
	`mkdir -p "${INDIR}/.thumbnails"`
	`fi`
	`cd "${INDIR}"`
	`tfs="$( find "${INDIR}" -mindepth 1 -maxdepth 1 ! -type d ! -name '..swp' ! -name '.sh' ! -name '*.html' -printf '%T@ %f\n' \| sort -n \| awk '{print $NF}' )"`
	`for word in ${tfs} ;`
	`do`
	`tf="${DIRPREFIX}/${word}"`
	`tf_thumb_web="${tf}"`
	`if test -n "${USE_THUMBNAILS}" && test "${USE_THUMBNAILS}" = 1 ;`
	`then`
	`tf_in="${INDIR}/${word}"`
	`tf_thumb="${INDIR}/.thumbnails/${word%%.???}.jpg"`
	`tf_thumb_web="${DIRPREFIX}/.thumbnails/${word%%.???}.jpg"`
	`convert -filter Lanczos -resize "${THUMBNAIL_SIZE}x${THUMBNAIL_SIZE}" "${tf_in}" "${tf_thumb}"`
	`fi`
	`echo "<a href=\"${tf}\"><img src=\"${tf_thumb_web}\" class=\"thumb\"></a>"`
	`done`

The find | sort | awk line is my preferred method for sorting by timestamp. It is not safe for files with spaces in the name, but who does that anyways?! (Ahem. [Well, not here obviously!]). Of course there are ways to make that happen, but it would be even less clean looking, and avoiding spaces is easy enough.

So like all good unix scripts, this just prints to stdout. I then copy-paste the contents and update my html file.

I haven't done extensive testing with non-square images. I'm pretty sure most images on my gallery are non-square, but everything seems to line up adequately.

And what gives away the fact that I'm a vim user?

And of course, some applicable css:

.thumb {
   max-width: 300px;
   max-height: 300px;
}

Use Images from Google Photos album as screensaver on Linux

bgstack15 — Thu, 21 May 2020 12:41:12 GMT

Introduction

I wanted to set up a (shared) Google Photos album as my screensaver on Devuan GNU/Linux. I accomplished this with the venerable xscreensaver and a useful tool named rclone which I was already using.

Downloading images from Google Photos

On my CentOS 7 server, I already am using rclone. Starting with version 1.49, rclone supports Google Photos. EPEL provides rclone but only version 1.47. So download the upstream rpm release: Downloads page or direct link. The utility comes with a cli-based configurator. Use rclone config and add a remote. I failed to save the output of when I configured it, but it's as easy following the prompts to add a Google Photos remote. Choose the headless option, and it will show you a link to open in a browser where you can authenticate to Google Photos and then approve this application to use a token tied to your account. The browser will show you a code you paste back into the configurator. In the end, what matters is that the ~/.config/rclone/rclone.conf includes a section like so:

[photos]
type = google photos
read_only = true
token = {"access_token":"za29.a0AfH6SMC9bVDgJTPZTPfvMd5MyplOehAgldvibfrlmMwOBFUSCATEDuDd6tMuWm13YOryXXpUWP4EkHO-oNoa92I6WN7rzrS4y6hquw3zPFXOayEZv-3uv9_NfYNUyctoBq_OUQ9lrqoH3U7J40crJW2NZ","token_type":"Bearer","refresh_token":"1//013Vdw5CGVJ3zCgZIARAAGAFSNwF-L9IricqZmAio2CqpFJ8nM0OuXmsorNlVHRmX5w_KeIgvwvrxsJl5hJT30jT9ET-9mh612-0","expiry":"2020-05-19T10:49:30.709779985-04:00"}

And then my sync script is this:

#!/bin/sh
# File: /etc/installed/sync-photos.sh
# Location: storage1:/etc/installed
# Author: bgstack15@gmail.com
# Startdate: 2020-05-19
# Title: Script that Pulls Down Album from Google Drive
# Purpose: Pull photos down for a screensaver for the living room HTPC
# History:
# Usage:
#    in a cron entry:
# References:
#    man rclone(1)
#    https://rclone.org/googlephotos/
# Dependencies:
#    ~/.config/rclone/rclone.conf with a section named "photos"
# Documentation:
#    --dry-run is useful. Sync command runs from left side to right side only.
REMOTE="photos"
INDIR="shared-album/Album Name"
OUTDIR=/mnt/public/Images/google-drive/photos
LOGFILE=/mnt/public/Support/Systems/storage1/var/log/sync-photos/rclone.photos.$( date "+%F" ).log
mkdir -p "$( dirname "${LOGFILE}" )"
PLECHO="$( which plecho 2>&1 || which cat )"
time rclone -v --gphotos-read-only sync "${REMOTE}:${INDIR}" "${OUTDIR}" 2>&1 | "${PLECHO}" | tee -a "${LOGFILE}"

The script itself ran great the first time, and downloaded all images (and videos) from the album. Upon second run though, the task seems stuck. Ah, well, I'll solve that over time. For a cron job to run this daily, add file /etc/cron.d/90_google-photos-sync.cron

# File: /etc/cron.d/90_google-photos-sync.cron
# for google photos album shared by another google user. Save down all images so that HTPC can use them in the screensaver.
45 04 *  *  *  root  /etc/installed/sync-photos.sh 1>/dev/null 2>&1

And as with all good cron jobs, suppress the standard output and standard error and use the job itself to store logs.

Using images in xscreensaver

On my Devuan GNU+Linux home theater PC, I use xscreensaver. To take advantage of a simple slideshow feature, make sure to have package xscreensaver-gl installed. Select GLSlideshow and option "Only one screen saver." The Tesselimage screensaver was very entertaining when used on personal photos but not all end users agreed with me. Adjust sliders as necessary. I found that on the default settings, the slideshow would fade out and back in, on the same photo, about three times, before finally moving on to the next image. So these sliders' positions were successful in always showing a new image on each fadeout, which was also slowed down. On the advanced settings tab of GLSlideshow, the sliders were instantiated as:

glslideshow -root -delay 30081 -duration 10 -pan 10

And of course, choose the destination directory (nfs mounted in my case) on the advanced settings. For the really hardcore users, some of the relevant .xscreensaver values I could find include:

chooseRandomImages: True
imageDirectory:   /mnt/public/Images/google-drive/photos
mode:    one
selected:       143
programs:                              \
- GL:             glslideshow -root -delay 30081 -duration      \
              10 -pan 10                \n\

It is worth noting that the glslideshow entry is 143 lines below the programs: line.

Extra thoughts

Even though a Google Photos album that is shared might be accessed anonymously, the rclone utility requires an account. Linux – keep it simple.

References

Upload user photo to AD

bgstack15 — Sat, 14 Dec 2019 14:02:01 GMT

I wrote a series of Powershell functions and scripts to perform a set of tasks. The new hires get their photo taken, and those photos need to be applied to the various systems that store user photos. More will be added over time, but now, I have functions that upload to Active Directory, Azure AD, Exchange, and a SQL Server database. As you might be aware, most of those systems only accept images up to a certain size. So I ripped off a function that resizes an image. I wrote a wrapper to shrink an image a little at a time until its size is smaller than the indicated value. Check out the whole repository at https://gitlab.com/bgstack15/former- gists/tree/master/userphotos. The basic task is to upload an image to Active Directory. A workflow in a Sharepoint instance handles the image uploads from users and the approval by a security officer, but then a script downloads all the photos Apply-Photos-From- SharePoint.ps1. The images are named according to the email address of the user already, so they're just downloaded wholesale. Once the files are on the local filesystem, that script loops through them and uploads them.

ForEach ($file in Get-ChildItem $Outdir | Where-Object { -Not ( $_.Name -Match ".*(_[0-9]{2}|[0-9]{6})\.[^.]{1,6}" ) } )
{
    $null = Process-User-Photo -File $file
}

In the library, the function Process-User-Photo extracts the user in question based on the name and calls the wrapper function for uploading to all services.

        $Result = Set-Photo-All -User $samaccountname -Filename $file.Fullname
        if ($Result -eq 0)
        {
            Log "Success: ${file}"
            Move-With-Rename -Path $file.Fullname -Destination "$MoveToOutdir\"
        }

And Set-Photo-All is pretty simple. It will return an integer which represents the number of failures of the individual set-photo functions.

# Set-Photo-All -User $User -Filename $Filename
Function Set-Photo-All {
    Param(
        [Parameter(Mandatory=$true)] $User,
        [Parameter(Mandatory=$true)] $Filename
    )
    $Result = 0
    $Result -= Set-Photo-AD -User $User -Filename $Filename
    # AzureAD synchronizes from on-prem AD approximately every 15 minutes.
    #$Result -= Set-Photo-AzureAD -User $User -Filename $Filename
    $Result -= Set-Photo-Outlook -User $User -Filename $Filename
    $Result -= Set-Photo-SQLServer -User $User -Filename $Filename
    return $Result
}

Uploading to AD is actually really easy.

# Set-Photo-AD -User $User -Filename $Filename
Function Set-Photo-AD {
    Param(
        [Parameter(Mandatory=$true)] $User,
        [Parameter(Mandatory=$true)] $Filename
    )
    $Result = -1
    $newfile = Get-Photo-Below-Size -Filename $filename -MaxSize 100000
    $photo = [byte[]](Get-Content $newfile -Encoding byte)
    Try
    {
        Get-ADUser $User | Set-ADUser -Replace @{thumbnailPhoto=$photo}
        If ($newfile -ne $Filename) { Remove-Item -Path $newfile }
        Log "Set AD photo for ${User} to ${newfile}"
        $Result = 0
    }
    Catch
    {
        Write-Error $_
    }
    Remove-Variable newfile
    return $Result
}

Of course there's a getter function as well, for each service.

# Get-Photo-AD -User $user -Filename $filename
Function Get-Photo-AD {
    Param (
        [Parameter(Mandatory=$True)] $user,
        [Parameter(Mandatory=$True)] $filename
    )
    # save photo down from AD to inspect it
    # https://devblogs.microsoft.com/scripting/weekend-scripter-exporting-and-importing-photos-in-active-directory/
    $user = get-aduser $user -properties thumbnailphoto
    [System.Io.File]::WriteAllBytes($filename,$user.thumbnailphoto)
}

So the whole library is modular. You can dot-source the whole thing and run just individual statements ad-hoc, or use the library for a wholistic solution which is why I needed it.

Remove docker "none" images

bgstack15 — Sat, 15 Dec 2018 13:57:29 GMT

docker rmi $( docker images -f "dangling=true" -q )

Shamelessly stolen from: https://forums.docker.com/t/how-to-remove-none- images-after-building/7050

Irfanview on Linux

bgstack15 — Thu, 19 Jan 2017 20:00:34 GMT

Overview

Irfanview is a fantastic image viewer and batch utility for the Windows platform. But did you know that you can run Irfanview on GNU/Linux, and this post will show you how to do that. There is a caveat, though: Irfanview is not open source. It's freeware. That might turn off some people, but I still choose to use it. It's unparalleled in the GNU world. There are several ways to get Irfanview on a GNU/Linux system, and they all use Wine.

Installing Irfanview with Winetricks

Winetricks is a fancy helper script that makes repetitive tasks in wine easier. It has an option built-in for installing Irfanview. It's a piece of cake. Make sure you have wine with your package manager. dnf install wine Then download winetricks from the link above and run the install irfanview command. ./winetricks -q irfanview The -q is for unattended install. If you want to adjust the settings, run it without the -q. Observe that winetricks mentions installing mfc42.dll for you. That is needed for the installer only.

Installing Irfanview with a custom-rolled package

You can choose to install Irfanview by assembling a package from the rpm spec and debian control scripts I've assembled at https://gitlab.com/bgstack15/irfan. git pull https://gitlab.com/bgstack15/irfan.git What is in the git repository is the source for just the packaging. The actual software source code is downloaded from official web sources upon building the rpm, and upon the installation of the dpkg file. As I said above, the software itself is freeware, so the source is not available for distribution. A wrapper for rpmbuild and dpkg-deb is provided, as usr/share/irfan/build/pack. Run ./pack rpm or ./pack deb and the system will build you the type of package you specified, provided you have the rpm-build or dpkg-dev package. For the rpm, you might need to generate some directories: mkdir -p ~/rpmbuild/SOURCES ~/rpmbuild/SPECS ~/rpmbuild/RPMS ~/rpmbuild/BUILD ~/rpmbuild/BUILDROOT In fact, you should run all this, which will download from gitlab for you the package source. mkdir -p ~/rpmbuild/SOURCES ~/rpmbuild/SPECS ~/rpmbuild/RPMS ~/rpmbuild/BUILD ~/rpmbuild/BUILDROOT cd ~/rpmbuild/SOURCES mkdir irfan-4.44-1; cd irfan-4.44-1 git init git pull https://gitlab.com/bgstack15/irfan.git cd irfan-4.44-1 usr/share/irfan/inc/pack rpm The generated rpm will appear in ~/rpmbuild/RPMS/noarch. Then you can run dnf install ./irfan-4.44-1.noarch.rpm.

The benefits of rolling your own package

The package provided on gitlab includes a menu shortcut to Irfanview, as well as mimetype defaults for jpg and png. You will be able to see Irfanview in the list of applications when you select a file in the file manager, right click, and select "Open with..." The winetricks option does not include that.

Reference

Main irfanview site http://www.irfanview.info/
http://www.boekhoff.info/?pid=linux&tip=install-irfan-view-on-linux
Main wine site https://www.winehq.org/
Latest winetricks script https://raw.githubusercontent.com/Winetricks/winetricks/master/src/winetricks
Irfan rpm and deb package source https://gitlab.com/bgstack15/irfan