Crop function now subtracts pixels instead of requiring specific window measurements

- Revamped crop functionality
- Merge pull request #43 from Daethyra/3.0.0

Author: Daethyra

README.md

@@ -64,7 +64,7 @@ Create a GIF from images or video:
 |------------------|--------|---------|--------------------------------------------------------------|
 | `--fps`          | float  | 24      | Frames per second                                            |
 | `--size`         | int int| -       | Max width and height (aspect ratio preserved)                |
-| `--crop`         | int int int int | - | Crop box: left top right bottom                         |
+| `--crop`         | int int int int | -       | Pixels to cut from each edge: left top right bottom. e.g. 0 20 0 20 trims 20px from top & bottom |
 | `--loop`         | int    | 0       | Loop count (0 = infinite)                                    |
 | `--start-time`   | float  | -       | Start time in seconds (video only)                           |
 | `--end-time`     | float  | -       | End time in seconds (video only)                             |
@@ -109,6 +109,10 @@ Reduce palette to 64 colors and turn off dithering for a crisp, retro look
 
     poetry run python -m transimage gif ./frames -o movie.gif --fps 12 --colors 64 --no-dither
 
+Remove 20px from top and bottom, resize to fit 640x480
+    
+    poetry run python -m transimage gif ./frames -o movie.gif --fps 12 --size 640 480 --crop 0 20 0 20
+
 ## Programmatic Usage
 
 Inside a script or interactive session, you can use the package directly after installing it in your environment.
@@ -184,6 +188,9 @@ Please submit issues regarding any oversight you see. Pull requests for improvem
 
 ## Changelog
 
+### 3.0.0 (25-06-2026)
+- Revamped `--crop` to be more intuitive. Crop now takes the number of pixels to cut off, instead of requiring the user to provide the exact measurements of 
+
 ### 2.1.0 (24-06-2026)
 - Added `--colors` and `--no-dither` arguments to give the user more control over a GIF's output file size.
 

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "transimage"
-version = "2.2.0"
+version = "3.0.0"
 description = "CLI tool for converting images between different formats and creating GIFs from image sequences, directories, or video files. Supports JPG, PNG, BMP, and WebP."
 authors = ["Daethyra <109057945+Daethyra@users.noreply.github.com>"]
 license = "MIT"

src/transimage/__main__.py

@@ -74,7 +74,7 @@ def main() -> None:
     )
     gif_parser.add_argument(
         "--crop", nargs=4, type=int, metavar=("L", "T", "R", "B"),
-        help="Crop box: left top right bottom"
+        help="Pixels to cut from each side: left top right bottom (e.g. --crop 0 20 0 20 removes 20px from top and bottom)"
     )
     gif_parser.add_argument("--loop", type=int, default=0, help="Loop count (0 = infinite)")
     gif_parser.add_argument("--start-time", type=float, default=None, help="Start time in seconds (video only)")

src/transimage/gif_creator.py

@@ -93,9 +93,20 @@ def _process_frames(self, images: List[Image.Image]) -> List[Image.Image]:
             if self.size:
                 img = img.copy()
                 img.thumbnail(self.size, self.resize_method)
-            # Crop if a box is given
+            # crop (cut amounts from each edge)
             if self.crop:
-                img = img.crop(self.crop)
+                left_cut, top_cut, right_cut, bottom_cut = self.crop
+                w, h = img.size
+                left = left_cut
+                top = top_cut
+                right = w - right_cut
+                bottom = h - bottom_cut
+                # Clamp to valid range (prevent zero/negative dimensions)
+                left = max(0, min(left, w))
+                top = max(0, min(top, h))
+                right = max(left, min(right, w))
+                bottom = max(top, min(bottom, h))
+                img = img.crop((left, top, right, bottom))
             # Ensure image is in RGB mode (GIF doesn't store alpha like PNG)
             if img.mode in ("RGBA", "LA", "P"):
                 background = Image.new("RGB", img.size, (255, 255, 255))