Resizing a boot animation.
This is the easy one to resize, first off you'll need a batch image resizer. The one I've always used is called faststone photo resizer available here,
http://www.faststone.org/FSResizerDownload.htm
Copy your downloaded bootanimation or the theme.mtz to your computer and extract it into a folder, (to extract an mtz you first need to turn it into a zip file by renaming it and adding .zip to the end instead of .mtz)
Ok so now in the folder you should have a file called desc.txt open that and change the values on the top line which relate to the size they will most likely be something like 480 800, change those 2 numbers to 240 320 which is the size of our screen, the final number relates to the speed or frames per second (fps) that the animation will play at. We are limited to 30fps so no need to go above 30 but this can be adjusted too if the animation is stuttering.
Next save this file then exit.
The next step is to resize the actual images so open the folder which contains the images, this is usually in parts named part 0 part 1 etc etc.
Start the photo resizer and a windows should open, the quickest way to load the images into it I think is to select them all in the folder then drag n drop them into the photo resizer input box.
Now click on the output folder button near the bottom right and select a folder where the new resized images will be created (I just use the same folder as where they came from, the old ones get overwritten)
Next its time to tell the resizer what to do so click on advanced options and tick the resize box, a few options should appear, we want to first choose to resize in pixels and set the width to 240 and the height to 320 then click ok or done or whatever??
It should go back to the main window now so click convert, select yes to all if it ask you if you want to overwrite images already in the folder and let it do its stuff.
Do the same for any other part folders i.e part 1.
Then zip it back up using winrar or 7zip the same way it was beforehand, named bootanimation.zip and store only.
Either adb push it to /system/media or use a file explorer and set permissions to rw__r__r__.
I will explain more about creating/adding it to an mtz file when/if I figure out why they don't seem to work for me.
Reboot and enjoy your new boot animation.
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Resizing miui clocks and photo frames.
By longpressing on the homescreen you'll find the widget selection screen, add a clock or photo frame then look in the top corner of the widget whilst still on the widget selection screen for a small black dot, tap that to go to the skin picker/download screen.
First download whichever clock you want to use and locate it in /sdcard/miui folder. Copy it to your pc and extract it into a folder.
In the folder you should have some images a description file and a manifest.xml first off we'll start by editing the manifest which tells the clocks where to place each image.
Open it with a text editor and change all the X and Y values by 50% then save it and exit.
Now we need to resize the actual images so open the image resizer and load all the images into it, choose the output folder and click advanced, this time though we should choose to resize by percentage and set it to 50% so everything lines up with the manifest.
Finally zip everything back up together same as it was before and copy it back to the relevant folder on your sdcard.
Longpress the homescreen and again choose your widget, tap the black dot and select your newly edited clock or photo frame, it should now fit but if it doesn't you'll need to extract it again and adjust it either way to get it to fit.