I need to convert OTF font to TTF font without losing quality. If it is possible how can I do it?
Starting from the beginning: both OpenType and TrueType fonts are SFNT based (i.e., the file formats are table-based) and very similar. What makes different an OpenType font is the presence of certain tables that enable advanced typographic features.
OpenType fonts can use one of the following to describe their glyphs:
- PostScript outlines (based on cubic bèzier curves), or
- TrueType outlines (based on quadratic curves).
TrueType fonts only use TrueType outlines.
Now I refer to my answer to another post: "...a Bézier curve of degree n can be converted into a Bézier curve of degree n+1 with the same shape (see Bézier Curve Degree Elevation). This means you can describe a TT Outline (Degree 2) exactly with a PS Outline (Degree 3), while you cannot do the same in the opposite direction (though you can do it as accurately as required)."
What this means, for your question, is:
- Talking about glyph quality, if the original OTF has TT outlines, no quality is lost. Otherwise, some quality will be lost in the conversion (I think the degradation will be minimal with a good conversion software).
- The advanced typographic features on the original OTF will be lost (if there were any).
Finally, you can do the conversion with, e.g., FontForge (which is free) or any other font editor (I can think of FontLab or Glyphs App, for example). For the specific HOW, check the corresponding software help or manual.