thumbnails: png output (#1345)

* thumbnails: png output

* fix tests

* lower resolution to 360

* fix tests

thumbnails/thumbnails.go

@@ -22,7 +22,7 @@ import (
 	"golang.org/x/sync/errgroup"
 )
 
-const resolution = "854:480"
+const resolution = "640:360"
 const vttFilename = "thumbnails.vtt"
 const outputDir = "thumbnails"
 
@@ -219,8 +219,6 @@ func processSegment(input string, thumbOut string) error {
 					"vframes": "1",
 					// video filter to resize
 					"vf": fmt.Sprintf("scale=%s:force_original_aspect_ratio=decrease", resolution),
-					// set quality
-					"q:v": "2",
 				},
 			).OverWriteOutput().WithErrorOutput(&ffmpegErr).Run()
 	}, clients.DownloadRetryBackoff())
@@ -254,5 +252,5 @@ func thumbFilename(segmentURI string, segmentOffset int64) (string, error) {
 	if err != nil {
 		return "", err
 	}
-	return fmt.Sprintf("keyframes_%d.jpg", i-segmentOffset), nil
+	return fmt.Sprintf("keyframes_%d.png", i-segmentOffset), nil
 }

thumbnails/thumbnails_test.go

@@ -104,31 +104,31 @@ func testGenerateThumbsRun(t *testing.T, outDir, input string) {
 
 	expectedVtt := `WEBVTT
 00:00:00.000 --> 00:00:10.000
-keyframes_0.jpg
+keyframes_0.png
 
 00:00:10.000 --> 00:00:20.000
-keyframes_1.jpg
+keyframes_1.png
 
 00:00:20.000 --> 00:00:30.000
-keyframes_2.jpg
+keyframes_2.png
 
 `
 
 	vtt, err := os.ReadFile(filepath.Join(outDir, "thumbnails/thumbnails.vtt"))
 	require.NoError(t, err)
 	require.Equal(t, expectedVtt, string(vtt))
 
-	files, err := filepath.Glob(filepath.Join(outDir, "thumbnails", "*.jpg"))
+	files, err := filepath.Glob(filepath.Join(outDir, "thumbnails", "*.png"))
 	require.NoError(t, err)
 	require.Len(t, files, 3)
 
 	for _, file := range files {
 		data, err := ffprobe.ProbeURL(context.Background(), file)
 		require.NoError(t, err)
-		require.Equal(t, "image2", data.Format.FormatName)
+		require.Equal(t, "png_pipe", data.Format.FormatName)
 		require.NotNil(t, data.FirstVideoStream())
-		require.Equal(t, 853, data.FirstVideoStream().Width)
-		require.Equal(t, 480, data.FirstVideoStream().Height)
+		require.Equal(t, 640, data.FirstVideoStream().Width)
+		require.Equal(t, 360, data.FirstVideoStream().Height)
 	}
 }
 
@@ -143,19 +143,19 @@ func Test_thumbFilename(t *testing.T) {
 			name:          "index",
 			segmentURI:    "index0.ts",
 			segmentOffset: 0,
-			want:          "keyframes_0.jpg",
+			want:          "keyframes_0.png",
 		},
 		{
 			name:          "clip",
 			segmentURI:    "clip_1.ts",
 			segmentOffset: 0,
-			want:          "keyframes_1.jpg",
+			want:          "keyframes_1.png",
 		},
 		{
 			name:          "clip",
 			segmentURI:    "clip_101.ts",
 			segmentOffset: 100,
-			want:          "keyframes_1.jpg",
+			want:          "keyframes_1.png",
 		},
 	}
 	for _, tt := range tests {