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PNG

The PNG format will accept either greyscale or RGB pixmaps, with or without alpha. As a special case, alpha only pixmaps are accepted and written as greyscale.


\begin{lstlisting} /* fz_save_pixmap_as_png: Save a pixmap as a PNG image file.... ...riter *fz_new_png_band_writer(fz_context *ctx, fz_output *out); \end{lstlisting}

Because PNG is such a useful and widely used format, we have another couple of functions. These take either a fz_image or a fz_pixmap and produce a fz_buffer containing a PNG encoded version. This is very useful when converting between document formats as we can frequently use a PNG version of an image as a replacement for other image formats that may not be supported.


\begin{lstlisting} /* Create a new buffer containing the image/pixmap in PNG fo... ..._buffer_from_pixmap_as_png(fz_context *ctx, fz_pixmap *pixmap); \end{lstlisting}