when I try to add a picture in high size or resolution, it gets HTTP ERROR 500. but there is no problem when I upload pictures at normal size. <1mb. Is there a solution?

@Şahin
Enable ImageMagick library in media settings.

Its enabled but not active in os class ? how can i active.

In ocadmin > settings >media

this is inactive

ask your hosting company

That library must be installed on hosting and speedup image conversion.

  i solve this problem. If you want to image magick, first you haveto write max siz mem. Thanx everybody