Get GPMF stream by id instead of hardcoding it (#82)

* Get GPMF stream by id instead of hardcoding it

* Test max videos

pkg/gopro/location_test.go

@@ -18,20 +18,29 @@ var videoTests = map[string]bool{
 	"hero6+ble.mp4": false,
 	"hero6.mp4":     true,
 	"hero6a.mp4":    true,
+
+	"hero7.mp4":        false,
+	"hero8.mp4":        false,
+	"max-360mode.mp4":  true,
+	"max-heromode.mp4": true,
 }
 
 func TestParseGPMF(t *testing.T) {
 	ctx := context.Background()
 
 	fs, err := gitfs.New(ctx, "github.com/gopro/gpmf-parser/samples",
-		gitfs.OptGlob("hero[5..6]*.mp4"))
+		gitfs.OptGlob("*.mp4"))
 	require.NoError(t, err)
 
 	walk := fsutil.Walk(fs, "")
 	for walk.Step() {
 		if walk.Path() == "" {
 			walk.Step()
 		}
+		if _, found := videoTests[walk.Path()]; !found {
+			walk.Step()
+		}
+
 		fmt.Printf("\tTesting [%s]", walk.Path())
 
 		remoteFile, err := fs.Open(walk.Path())
@@ -43,7 +52,7 @@ func TestParseGPMF(t *testing.T) {
 		stat, err := remoteFile.Stat()
 		require.NoError(t, err)
 
-		buf := make([]byte, stat.Size()) // roughly 290 bytes per SRT entry
+		buf := make([]byte, stat.Size())
 
 		_, err = remoteFile.Read(buf)
 		require.NoError(t, err)

pkg/utils/ffprobe.go

@@ -50,6 +50,13 @@ type GPSLocation struct {
 	} `json:"format"`
 }
 
+type StreamsResponse struct {
+	Streams []struct {
+		Index          int    `json:"index"`
+		CodecTagString string `json:"codec_tag_string"`
+	} `json:"streams"`
+}
+
 func NewFFprobe(path *string) FFprobe {
 	ff := FFprobe{}
 	if path == nil {
@@ -107,6 +114,33 @@ func (f *FFprobe) executeGetInfo(path string, entries ...string) ([]byte, error)
 	return out.Bytes(), nil
 }
 
+func (f *FFprobe) Streams(path string) (*StreamsResponse, error) {
+	result := StreamsResponse{}
+
+	args := []string{
+		"-show_streams",
+		"-of",
+		"json",
+		path,
+	}
+	_, err := os.Stat(path)
+	if err != nil {
+		return nil, err
+	}
+	cmd := exec.Command(f.ProgramPath, args...) // #nosec
+	var out bytes.Buffer
+	cmd.Stdout = &out
+	err = cmd.Run()
+	if err != nil {
+		return nil, err
+	}
+	err = json.Unmarshal(out.Bytes(), &result)
+	if err != nil {
+		return nil, err
+	}
+	return &result, nil
+}
+
 func (f *FFprobe) VideoSize(path string) (*VideoSizeResponse, error) {
 	result := VideoSizeResponse{}
 	out, err := f.executeGetInfo(path, "width", "height", "r_frame_rate")

pkg/videomanipulation/ffmpeg.go

@@ -10,6 +10,7 @@ import (
 	"strings"
 	"sync"
 
+	"github.com/konradit/mmt/pkg/utils"
 	"github.com/vbauerster/mpb/v8"
 	"github.com/xfrr/goffmpeg/ffmpeg"
 	"github.com/xfrr/goffmpeg/transcoder"
@@ -147,8 +148,19 @@ func (v *VMan) ExtractGPMF(input string) (*[]byte, error) {
 	if err != nil {
 		return nil, err
 	}
+	ffprobe := utils.NewFFprobe(nil)
 
-	v.trans.MediaFile().SetRawOutputArgs([]string{"-map", "0:3"})
+	streams, err := ffprobe.Streams(input)
+	if err != nil {
+		return nil, err
+	}
+	gpmfStream := 3
+	for _, stream := range streams.Streams {
+		if stream.CodecTagString == "gpmd" {
+			gpmfStream = stream.Index
+		}
+	}
+	v.trans.MediaFile().SetRawOutputArgs([]string{"-map", fmt.Sprintf("0:%d", gpmfStream)})
 	v.trans.MediaFile().SetOutputFormat("rawvideo")
 	v.trans.MediaFile().SetVideoCodec("copy")