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tg1911
Resizing An Animated GIF



Guide Overview

The purpose of this guide is to teach you how to take an Animated GIF file, and reduce the size of it.
One of the reasons you might want to reduce the size of the GIF, you have a nice animation you want to use as an avatar on this forum. For the purpose of this tutorial, let's assume the GIF is 100 pixels wide x 100 pixels high. This forum will not support an avatar that is larger than 83 pixels high x 83 pixels wide, so it needs to be resized to work properly.

An animated GIF, is a file made up of layers of images, stacked one on top of the other.
In each layer, the image is a little bit different than the previous image.
So, when each image is "flipped through" at a given speed, the image appears to move, like a flip-book.
This is a rather simplistic explanation, but that's how it basically works.

If you try to use a GIF larger than 83 x 83, the forum's software will reduce it to those dimensions. Since the software doesn't support animation resizing, the first image that makes up the animated file will be resized. It will ignore, and discard, the other images, leaving you with an image that is not animated.

This Tutorial will be broken into 2 parts.
The first part will deal with using Irfanview, to extract the frames of the GIF, then resize and convert them.
The second part will discuss the actual re-compiling, of the extracted frames.

A short Flash presentation is also available for viewing. As there are several steps involved, and the use of 2 programs, I suggest you first read through the tutorial to familiarize yourself with the process, then watch the video,
If you still have question rereading the Tutorial, should answer most of them.
The written Tutorial, will give you a bit more detail about the Resizing operation.
Animated GIF Resizing Video

Tools NeededInstructions: Part 1
  1. Open Irfanview, click File, and select Open.

  2. Navigate to the GIF you want to resize, highlight it, and click the Open button.
    This will load the file into Irfanview.



  3. Click Options, and select Extract all frames..., which will seperate the animation into it's individual frames.



    This will open the Browse for Folder dialog box.

  4. Select the folder you want the extracted frames sent to, and click OK.



  5. Click File again, and select Batch Conversion/Rename...
    This will open the Batch conversion dialog box.



  6. Click the dropdown arrow next to the Look in: box, and navigate to the folder you extracted the GIF frames to.
    Use the dropdown arrow next to the Files of type: box, to make sure BMP/DIB/RLE is selected.

  7. Highlight the extracted files, and click the Add button.



    This will add the files to the Input files: list.



  8. In the Output directory: section, click the Browse button, which will open the Browse for Folders dialog box, and navigate to where you want the converted files saved.



  9. In the Work as: section, put a tick next to Batch conversion.



  10. In the Batch conversion settings: section, under Output format:, use the dropdown arrow to select GIF.



  11. Click the Options button.
    This will open the JPEG/GIF save options dialog box.



    In the GIF section, the only thing that should be checked is, Save interlaced.



    Click the OK button.

  12. On the right, put a check in the Use advanced options box.
    This will activate the Set advanced options button.



  13. Click the Set advanced options button.
    This will open the Settings for all images: dialog box.



  14. This is a list of what should be checked/ticked in this dialog box:
    Resize
    Set new size:
    pixels
    Set long side to: (type 83 in the box, as shown)
    Preserve aspect ratio (proportional)
    Use Resample function (better quality)

    If anything else is checked, remove the checks/ticks, then click the OK button.

    NOTE:
    These settings will remain the same, everytime you open Irfanview, unless you change them, so if you have several GIF's to convert, you won't have to reset them.

  15. Click the Start button.



  16. You'll see the files being processed.



    When it's finished, click the Exit button.

  17. Close Irfanview.
That concludes the extraction, conversion, and resizing part of the operation.
That wasn't too hard, was it?
Now, on to the making of the animated GIF.
tg1911
Instructions: Part 2
  1. Open Windows Explorer, and navigate to where you saved the converted files.



  2. Open unFREEz.

  3. Resize the window containing the converted files, so you can put unFREEz underneath it.



    If you put unFREEz on the window, and you go to select the files, it will hide unFREEz behind the window.
    When you select unFREEz to bring it to the front, it will deselect the files, so you'll end up going in circles, trying to view them both.

  4. Highlight the converted files, and grab (left click, and hold the button down) the first file.



  5. Drag them into unFREEz's window.




    NOTE:
    If you don't grab the first file, when dragging into unFREEz's window, there's a possibility of the files not being loaded in the proper order. Grabbing the first file, while dragging, will insure they are loaded properly.

  6. Make sure the Loop animation box is checked.



  7. Set the Frame delay: to what ever value you want.



    NOTE:
    This will take some "playing around" on your part. An entry of 1 (one), will give you a frame delay of 1/100 of a second, so an entry of 100, equals 1 second.
    I'll explain more about this in the following steps.

  8. Click the Make Animated GIF button.



  9. This will open the Make Animated GIF dialog box.
    In the Save in: box, pick a place to save the new GIF.
    In the File name: box, give it the name of 1 (I'll explain this in a minute), and click the Save button.



  10. Open Irfanview, and make sure you can have more than one instance of Irfanview open, at a time.
    Options / Properties... / Misc. 1 tab / uncheck Only 1 instance of Irfanview is active

  11. Click View, then Display options, and select Do not fit anything.

  12. Open the resized GIF you just made, in Irfanview.

  13. Open the original GIF in another instance of Irfanview.

  14. Put the 2 Irfanview windows side by side, so you can compare the 2 GIFS.



    Depending on what you set the Frame delay: at, in unFREEz, your new GIF will probably not be moving at the same speed, as the original. Here's where the "playing around" comes in.
    If your new GIF is moving slower than the original, the Frame delay: will have to be set to a lower number.
    If your new GIF is moving faster than the original, the Frame delay: will have to be set to a higher number.

  15. Go back to Step #4, and repeat, adjusting the value in Frame delay: up, or down, as needed.
    Each time you have to repeat these steps, name the created GIF's in sequential order; 1, 2, 3, etc.

  16. When you have an acceptable animation, delete the others, and rename the completed animation with a name of your choosing.
While reading through this, it may seem like a rather involved process, but it's not really that hard.
As you do it a few times, it becomes much easier.
Just take your time, and enjoy. smile.gif
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