Does your feature request involve difficulty for you to complete a task? Please describe.
Currently, when a folder has many images and compressed by picsharp, overwrite original file mode. There is no way to indentify which one is compressed. Especially the folder maybe added more new uncompressed images.
[目前当一个文件夹的图片被压缩后，使用了覆盖原文件模式，就没有办法区分哪些是已经压缩的，哪些是未压缩。特别是该文件夹后续又更新了大量新图片]
Describe the solution you'd like
Create a .compressed file in folder, recording a compressed file list. Scan the list before compressing. Only files not in the list should be compressed.
[文件夹内新建一个.compressed文件，里面记录了该文件夹内已经压缩过的文件列表。程序压缩前先扫描此文件内的列表。如果不在此列表中，才进行压缩。]
Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.
Additional context
Idea comes from .gitignore
Does your feature request involve difficulty for you to complete a task? Please describe.
Currently, when a folder has many images and compressed by picsharp, overwrite original file mode. There is no way to indentify which one is compressed. Especially the folder maybe added more new uncompressed images.
[目前当一个文件夹的图片被压缩后，使用了覆盖原文件模式，就没有办法区分哪些是已经压缩的，哪些是未压缩。特别是该文件夹后续又更新了大量新图片]
Describe the solution you'd like
Create a .compressed file in folder, recording a compressed file list. Scan the list before compressing. Only files not in the list should be compressed.
[文件夹内新建一个.compressed文件，里面记录了该文件夹内已经压缩过的文件列表。程序压缩前先扫描此文件内的列表。如果不在此列表中，才进行压缩。]
Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.
Additional context
Idea comes from .gitignore