ffmpeg: Error out with 0x0 transcoding profiles

One side can still be nonzero since we will take the larger.

ffmpeg/ffmpeg.go

@@ -549,6 +549,10 @@ func createCOutputParams(input *TranscodeOptionsIn, ps []TranscodeOptions) ([]C.
 				return params, finalizer, err
 			}
 		}
+		if w <= 0 && h <= 0 {
+			// fail if both <= 0. if one is nonzero, we will take the larger
+			return params, finalizer, ErrTranscoderRes
+		}
 		br := strings.Replace(param.Bitrate, "k", "000", 1)
 		bitrate, err := strconv.Atoi(br)
 		if err != nil {

ffmpeg/ffmpeg_test.go

@@ -176,6 +176,8 @@ func runResolutionTests_H264(t *testing.T, accel Acceleration) {
 		target string
 		// expected width and height
 		expected string
+		// expected error
+		err error
 	}{{
 		name:     "h > w",
 		input:    "150x200",
@@ -236,6 +238,11 @@ func runResolutionTests_H264(t *testing.T, accel Acceleration) {
 		input:    "123x123",
 		target:   "426x0",
 		expected: "426x426",
+	}, {
+		name:   "zero",
+		input:  "300x200",
+		target: "0x0",
+		err:    ErrTranscoderRes,
 	}}
 
 	for i, tt := range tests {
@@ -254,11 +261,13 @@ func runResolutionTests_H264(t *testing.T, accel Acceleration) {
 				Profile: VideoProfile{Resolution: tt.target, Bitrate: "50k"},
 				Accel:   accel,
 			}})
-			assert.Nil(t, err)
+			assert.Equal(t, tt.err, err)
 			cmd = fmt.Sprintf(`
 					echo '%s'
 					ffprobe -hide_banner -show_entries stream=width,height -of csv=p=0:s=x out-test-%d.mp4 | grep %s`, tt.name, i, tt.expected)
-			run(cmd)
+			if tt.err == nil {
+				run(cmd)
+			}
 		})
 	}
 	// TODO set / check sar/dar values?