Gadgets: color based video and image cutting

1 Preface

Recently, I worked on a short video related project , I found that many of the input videos have black edges , Some may be white edges or edges of other colors . This has a great impact on downstream model processing . So I wrote an automatic judge of the color of the filling edge , A gadget that automatically cuts video or pictures according to the color . This is really convenient , So share it .

The code is visible https://github.com/zjuPeco/color_base_image_crop.

2 Brief description of the scheme

All colors will rgb Values map to hsv After space , Then map to a color table summarized in advance . Every hsv Corresponding to a name in the color table .

For video cutting ：
（1） Read the first frame of the video .
（3） If no background color is specified , According to the four corners of the picture block, Take the mode to infer the background color .block_size Can be set up .
（3） Get the color name corresponding to each pixel in the whole image , obtain mask.
（4） according to mask Select cut point , First, find it in the direction of width , And then find it according to the height .
（5） All frames of the video are cut according to the cutting point .
（6） Output the cut image to the specified size .

For image cutting ：
（1） If no background color is specified , According to the four corners of the picture block, Take the mode to infer the background color .block_size Can be set up .
（2） Get the color name corresponding to each pixel in the whole image , obtain mask.
（3） according to mask Select cut point , First, find it in the direction of width , And then find it according to the height , And then find it in the direction of width .
（4） Output the cut image to the specified size .

3 effect

（1） Cut video , And output according to the cutting size .

python3 codes/crop_video_by_color.py --input_video ./data/1.mp4 --output_video ./results/videos/1.mp4

chart 3-1 Cut to original size

（2） Cut video , And press resize after crop Output to the specified size

python3 codes/crop_video_by_color.py --input_video ./data/1.mp4 --output_video ./results/videos/1_720x1080.mp4 --output_size 720x1080

chart 3-2 resize after crop To the specified size

（3） Cut video , And press resize after pad To the specified size

python3 codes/crop_video_by_color.py --input_video ./data/1.mp4 --output_video ./results/videos/1_720x1080_pad.mp4 --output_size 720x1080 --pad_mode outside

chart 3-3 resize after pad To the specified size （4） Cut the picture , Output according to the cutting size

python3 codes/crop_image_by_color.py --input_image ./data/5.jpeg --output_image_dir ./results/images/5/

chart 3-4 Cut multiple small drawings