From dafa26435e8c5514433ac9e31459650ef56fe43d Mon Sep 17 00:00:00 2001
From: John Cupitt <jcupitt@gmail.com>
Date: Fri, 13 Jan 2017 12:37:19 +0000
Subject: [PATCH] only use webp presets in lossy mode

it seems lossless and near-lossless modes have a separate preset system

see https://github.com/jcupitt/libvips/issues/578
---
 libvips/foreign/vips2webp.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/libvips/foreign/vips2webp.c b/libvips/foreign/vips2webp.c
index 5447c24c..a50d660b 100644
--- a/libvips/foreign/vips2webp.c
+++ b/libvips/foreign/vips2webp.c
@@ -237,7 +237,18 @@ write_webp( WebPPicture *pic, VipsImage *in,
 	WebPConfig config;
 	webp_import import;
 
-	if ( !WebPConfigPreset( &config, get_preset( preset ), Q ) ) {
+	if( !WebPConfigInit( &config ) ) {
+		vips_error( "vips2webp",
+			"%s", _( "config version error" ) );
+		return( -1 );
+	}
+
+	/* These presets are only for lossy compression. There seems to be
+	 * separate API for lossless or near-lossless, see
+	 * WebPConfigLosslessPreset().
+	 */
+	if( !(lossless || near_lossless) &&
+		!WebPConfigPreset( &config, get_preset( preset ), Q ) ) {
 		vips_error( "vips2webp", "%s", _( "config version error" ) );
 		return( -1 );
 	}