Constant libjxl_sys::JXL_DEC_NEED_PREVIEW_OUT_BUFFER

pub const JXL_DEC_NEED_PREVIEW_OUT_BUFFER: JxlDecoderStatus = 3;

The decoder is able to decode a preview image and requests setting a preview output buffer using JxlDecoderSetPreviewOutBuffer. This occurs if JXL_DEC_PREVIEW_IMAGE is requested and it is possible to decode a preview image from the codestream and the preview out buffer was not yet set. There is maximum one preview image in a codestream.