wkentaro
commented
9 years ago I should have written about the use cases.
I added these functions to use them when converting subscribed image msg to image which has desired encoding. If to mono8, cv_bridge automatically converts msg, but if not auto converting does not work. So in these cases, I need to convert image encoding using other methods like cv::cvtColor, and I need to know the image msg is BGR/RGB/BGRA/RGBA at this time. I thought these utility functions are useful for that. Are there any other way?
2015年5月11日月曜日、Tully Footenotifications@github.comさんは書きました:
Generally I'd prefer to avoid one line inline functions which the user can trivially reproduce. I'm not sure these methods will save the end user code complexity, since to be able to iterate you will need to know the size, so even if you use these methods you will need another conditional to operate on the data.
What are your use cases where you want to know the order but not the size of the encoding?
Exposing more semantically meaningful methods like isBGROrder which tests all 4 bgr encodings would seem more powerful.
There's also an hasAlpha method which could be used with the ordering to give the same results as the methods defined.
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vrabaud
Generally I'd prefer to avoid one line inline functions which the user can trivially reproduce. I'm not sure these methods will save the end user code complexity, since to be able to iterate you will need to know the size, so even if you use these methods you will need another conditional to operate on the data.
What are your use cases where you want to know the order but not the size of the encoding?
Exposing more semantically meaningful methods like isBGROrder which tests all 4 bgr encodings would seem more powerful.
There's also an hasAlpha method which could be used with the ordering to give the same results as the methods defined.