Does someone can help me> My work is based on hd pictures and made some modifications on them with Photoshop CC. Then, I saved them on a JPEG2000 files but i m not sure it is the best quality to be adapted on a website and video. When I save them for the website in JPEG as presented on the Photoshop tutorials, the quality isn't that good. How can I optimize it?
If your document image quality is good after you resize the image document for the web saving a quality 10 Jpeg image should decode with good image quality. What are you exact Photoshop steps the produce the unacceptable image file.
JPEG 2000 was a nice idea when it was originally proposed in 1999. But it never really took off.
Regular JPEG format is the MIME file type we see supported most by commercial servers and web browsers. If you're saving high end graphics for other uses, I would keep a RAW file.
In PS, use the Save for Web option as optimized JPEG. See screenshot. Use the 4-up panel to compare quality vs file size. Ideally, you want the best quality with the least file size you can get away with so you're not killing mobile data plans with excessive bandwidth.