imwrite Compression parameters

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Lossless jpeg actually exists, that's why I was wondering. If imwrite(test.jpg,CV_IMWRITE_JPEG_QUALITY,100) is lossy, is it possible to have a lossless jpeg compression with OpenCV?

To cite wikipedia: "Lossless JPEG was developed as a late addition to JPEG in 1993, using a completely different technique from the lossy JPEG standard.[...] It is not supported by the standard Independent JPEG Group libraries, although Ken Murchison of Oceana Matrix Ltd. wrote a patch that extends the IJG library to support Lossless JPEG. Lossless JPEG has some popularity in medical imaging, and is used in DNG and some digital cameras to compress raw images, but otherwise was never widely adopted.". I extremly doubt that your system's jpeg library (afaik OpenCV uses the system's libraries for IO) uses losless jpeg! Afaik it also doesn't use JPEG2000. By the way, your downvote is not understandable and discourages me and others to help you further.

Just came across this: http://stackoverflow.com/questions/7982409/is-jpeg-lossless-when-quality-is-set-to-100 . They basically say the same, i.e. it depends on the library the System and thus OpenCV uses for compression.