From a8090ff47ecce8443b0bb0da5b19b22aaacc4f1f Mon Sep 17 00:00:00 2001
From: Nova Kwok <n0vad3v@riseup.net>
Date: Thu, 15 Jun 2023 17:10:53 +0800
Subject: [PATCH] Ignore sisze when source is GIF (#233)

* Ignore sisze when source is GIF

* error strings should not be capitalized (ST1005)
---
 encoder.go | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/encoder.go b/encoder.go
index df97fde..4e3a807 100644
--- a/encoder.go
+++ b/encoder.go
@@ -114,6 +114,17 @@ func avifEncoder(p1, p2 string, quality int, extraParams ExtraParams) error {
 		return err
 	}
 
+	// Ignore Unknown, WebP, AVIF
+	ignoreList := []vips.ImageType{vips.ImageTypeUnknown, vips.ImageTypeWEBP, vips.ImageTypeAVIF}
+
+	imageFormat := img.Format()
+	for _, ignore := range ignoreList {
+		if imageFormat == ignore {
+			// Return err to render original image
+			return errors.New("encoder: ignore image type")
+		}
+	}
+
 	if config.EnableExtraParams {
 		err = resizeImage(img, extraParams)
 		if err != nil {
@@ -175,6 +186,17 @@ func webpEncoder(p1, p2 string, quality int, extraParams ExtraParams) error {
 		return err
 	}
 
+	// Ignore Unknown, WebP, AVIF
+	ignoreList := []vips.ImageType{vips.ImageTypeUnknown, vips.ImageTypeWEBP, vips.ImageTypeAVIF}
+
+	imageFormat := img.Format()
+	for _, ignore := range ignoreList {
+		if imageFormat == ignore {
+			// Return err to render original image
+			return errors.New("encoder: ignore image type")
+		}
+	}
+
 	if config.EnableExtraParams {
 		err = resizeImage(img, extraParams)
 		if err != nil {
@@ -183,7 +205,8 @@ func webpEncoder(p1, p2 string, quality int, extraParams ExtraParams) error {
 	}
 
 	// The maximum pixel dimensions of a WebP image is 16383 x 16383.
-	if img.Metadata().Width > webpMax || img.Metadata().Height > webpMax {
+	// But GIF is exception, it can be larger than 16383
+	if (img.Metadata().Width > webpMax || img.Metadata().Height > webpMax) && imageFormat != vips.ImageTypeGIF {
 		return errors.New("WebP: image too large")
 	}