Kkots GIFTools

Description

Provides command-line utilities for Windows and Linux to perform following tasks:

• Given a set of files named file1.png, file2.png, file3.png and so on, renumber them to, for example, file2.png, file3.png, file4.png;
• Given a GIF file print or modify its frames durations (careful: not all GIF files may be supported);
• Given a set of files named file1.png, file2.png, file3.png and so on, delete every second file and renumber the rest so that they are numbered consecutively.

Usage

Tools are meant to be used from the command line. On Windows you open the command line by:

• Pressing Win+R and typing cmd, then pressing Enter;
• Or pressing Win key, typing Command Prompt into the search, then pressing Enter;
• Other ways.

There are two way to speed up copying file paths into the Windows command prompt:

• Way 1:
  • Select the file in Windows Explorer;
  • Copy the file using Ctrl+C shortcut;
  • Press Win+R, which opens the Run prompt;
  • Paste the file into the Run prompt using Ctrl+V shortcut;
  • The full file path gets pasted with the quotation marks;
  • You can now copy this file path and paste it elsewhere.
• Way 2:
  • Drag and drop the file from the Windows Explorer window into the Command Prompt window.

renumber_frames usage

renumber_frames is the command that does this:

• Given a set of files named file1.png, file2.png, file3.png and so on, renumber them to, for example, file2.png, file3.png, file4.png;

Example usage:

D:\source\repos\GIFTools\Release\renumber_files.exe "D:\source\repos\GIFTools\screens\screen%.png" 48-58 49

The above example shifts frames 48-58 forward one frame, so they now become 49-59.

General syntax is:

D:\source\repos\GIFTools\Release\renumber_files.exe <path> <start>-<end> <destination>

• path - the path to the frame file, with the number part replaces with % signs. You can increase the number of % signs if you want the number to be padded with zeros on the left;
• start - this is the starting frame number to move;
• end - this is the ending frame number to move, inclusive;
• destination - this is the destination frame number to which the start frame would get moved. The start+1 frame would get moved into destination+1 and so on;

change_gif_durations

change_gif_durations is the command that does this:

• Given a GIF file print or modify its frames durations (careful: not all GIF files may be supported);

Printing GIF frame durations

Example usage:

D:\source\repos\GIFTools\Release\change_gif_durations.exe D:\source\repos\GIFTools\screens\out.gif -f > "D:\source\repos\GIFTools\screens\durations.txt"

The above example prints the duration of each frame of the GIF into the durations.txt text file that gets created. The duration is in milliseconds, and each frame duration is represented by a number on a new line.

General syntax is:

D:\source\repos\GIFTools\Release\change_gif_durations.exe [path] -f > [output]

• path - the path to the GIF file;
• output - the path to the text file that will be created and will contain the durations.

The command also supports a more human-readable output, using the -u switch. Example:

D:\source\repos\GIFTools\Release\change_gif_durations.exe D:\source\repos\GIFTools\screens\out.gif -f -u

Example output:

1-13: 50 ms (20 fps)
14: 2000 ms (1 fps)
15-57: 50 ms (20 fps)
Average duration: 84 ms
Average framerate: 12 fps
Finished successfully.

Changing GIF frame durations using -duration

Example usage:

D:\source\repos\GIFTools\Release\change_gif_durations.exe D:\source\repos\GIFTools\screens\out.gif 0-20 -duration 1000

The above example sets durations for frames 0-20 to 1000 milliseconds (or 1 second) each. Frames are labeled starting from 0.

Changing GIF frame durations using -fps

Example usage:

D:\source\repos\GIFTools\Release\change_gif_durations.exe D:\source\repos\GIFTools\screens\out.gif 0-20 -fps 30

The above example sets the framerate for frames 0-20 to 30 frames per second. The rest of the frames are unaffected. Frames are labeled starting from 0.
This is actually the same as using -duration 33 (because 33 = 1000 / 30).

Changing GIF frame durations using -durations

You can use a text file which specifies duration for each frame in order to set GIF frame durations. Such text file must contain a frame duration in milliseconds on each line for all GIF frames. You're not allowed to specify a frame range in this approach. The durations text file can be exported from the GIF file by using the -f option (described in previous sections).

Example usage:

D:\source\repos\GIFTools\Release\change_gif_durations.exe D:\source\repos\GIFTools\screens\out.gif -durations D:\source\repos\GIFTools\screens\durations.txt

This will set each frame's duration to the corresponding value in durations.txt.