From 8c32265ae367f91f28b095a025e060e96893177b Mon Sep 17 00:00:00 2001
From: Ella Pietraroia <ella@ausocean.org>
Date: Tue, 31 Dec 2019 15:29:58 +1030
Subject: [PATCH] error message for decoding image

---
 filter/knn.go | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/filter/knn.go b/filter/knn.go
index d4eb13ed..cc65d1de 100644
--- a/filter/knn.go
+++ b/filter/knn.go
@@ -29,6 +29,7 @@ LICENSE
 package filter
 
 import (
+	"fmt"
 	"image"
 	"image/color"
 	"io"
@@ -74,7 +75,10 @@ func (m *KNNFilter) Close() error {
 // Write applies the motion filter to the video stream. Only frames with motion
 // are written to the destination encoder, frames without are discarded.
 func (m *KNNFilter) Write(f []byte) (int, error) {
-	img, _ := gocv.IMDecode(f, gocv.IMReadColor)
+	img, err := gocv.IMDecode(f, gocv.IMReadColor)
+	if err != nil {
+		return 0, fmt.Errorf("can't decode image: %w", err)
+	}
 	defer img.Close()
 
 	imgDelta := gocv.NewMat()