use libffmpeg to parse video frame and vid information

apiGo/videoparser/thumbnail/Thumbnailparser.go

@@ -0,0 +1,22 @@
+package thumbnail
+
+import (
+	"encoding/base64"
+	"fmt"
+)
+
+type VidInfo struct {
+	Width     uint32
+	Height    uint32
+	Length    uint64
+	FrameRate float32
+	Size      int64
+}
+
+func EncodeBase64(data *[]byte, mimetype string) *string {
+	strEncPic := base64.StdEncoding.EncodeToString(*data)
+	backpic64 := fmt.Sprintf("data:%s;base64,%s", mimetype, strEncPic)
+
+	return &backpic64
+
+}

apiGo/videoparser/thumbnail/Thumbnailparser_shared_ffmpeg.go

@@ -0,0 +1,183 @@
+// +build sharedffmpeg
+
+package thumbnail
+
+import (
+	"github.com/3d0c/gmf"
+	"io"
+	"log"
+	"os"
+)
+
+func Parse(filename string, time uint64) (*string, *VidInfo, error) {
+	dta, inf, err := decodePic(filename, "png", time)
+	if len(dta) > 0 && err == nil {
+		// base64 encode picture
+		enc := EncodeBase64(dta, "image/png")
+		return enc, inf, nil
+	} else {
+		return nil, nil, err
+	}
+}
+
+func decodePic(srcFileName string, decodeExtension string, time uint64) (pic *[]byte, info *VidInfo, err error) {
+	var swsctx *gmf.SwsCtx
+
+	stat, err := os.Stat(srcFileName)
+	if err != nil {
+		// file seems to not even exist
+		return nil, nil, err
+	}
+	fileSize := stat.Size()
+
+	inputCtx, err := gmf.NewInputCtx(srcFileName)
+
+	if err != nil {
+		log.Printf("Error creating context - %s\n", err)
+		return nil, nil, err
+	}
+	defer inputCtx.Free()
+
+	srcVideoStream, err := inputCtx.GetBestStream(gmf.AVMEDIA_TYPE_VIDEO)
+	if err != nil {
+		log.Printf("No video stream found in '%s'\n", srcFileName)
+		return nil, nil, err
+	}
+
+	codec, err := gmf.FindEncoder(decodeExtension)
+	if err != nil {
+		log.Printf("%s\n", err)
+		return nil, nil, err
+	}
+
+	cc := gmf.NewCodecCtx(codec)
+	defer gmf.Release(cc)
+
+	cc.SetTimeBase(gmf.AVR{Num: 1, Den: 1})
+
+	cc.SetPixFmt(gmf.AV_PIX_FMT_RGBA).SetWidth(srcVideoStream.CodecPar().Width()).SetHeight(srcVideoStream.CodecPar().Height())
+	if codec.IsExperimental() {
+		cc.SetStrictCompliance(gmf.FF_COMPLIANCE_EXPERIMENTAL)
+	}
+
+	if err := cc.Open(nil); err != nil {
+		log.Println(err)
+		return nil, nil, err
+	}
+	defer cc.Free()
+
+	ist, err := inputCtx.GetStream(srcVideoStream.Index())
+	if err != nil {
+		log.Printf("Error getting stream - %s\n", err)
+		return nil, nil, err
+	}
+	defer ist.Free()
+
+	err = inputCtx.SeekFrameAt(int64(time), 0)
+	if err != nil {
+		log.Printf("Error while seeking file: %s\n", err.Error())
+		return
+	}
+
+	// convert source pix_fmt into AV_PIX_FMT_RGBA
+	// which is set up by codec context above
+	icc := srcVideoStream.CodecCtx()
+	if swsctx, err = gmf.NewSwsCtx(icc.Width(), icc.Height(), icc.PixFmt(), cc.Width(), cc.Height(), cc.PixFmt(), gmf.SWS_BICUBIC); err != nil {
+		panic(err)
+	}
+	defer swsctx.Free()
+
+	frameRate := float32(ist.GetRFrameRate().AVR().Num) / float32(ist.GetRFrameRate().AVR().Den)
+	inf := VidInfo{
+		Width:     uint32(icc.Width()),
+		Height:    uint32(icc.Height()),
+		FrameRate: frameRate,
+		Length:    uint64(inputCtx.Duration()),
+		Size:      fileSize,
+	}
+
+	info = &inf
+
+	var (
+		pkt        *gmf.Packet
+		frames     []*gmf.Frame
+		drain      int = -1
+		frameCount int = 0
+	)
+
+	for {
+		if drain >= 0 {
+			break
+		}
+
+		pkt, err = inputCtx.GetNextPacket()
+		if err != nil && err != io.EOF {
+			if pkt != nil {
+				pkt.Free()
+			}
+			log.Printf("error getting next packet - %s", err)
+			break
+		} else if err != nil && pkt == nil {
+			drain = 0
+		}
+
+		if pkt != nil && pkt.StreamIndex() != srcVideoStream.Index() {
+			continue
+		}
+
+		frames, err = ist.CodecCtx().Decode(pkt)
+
+		if err != nil {
+			log.Printf("Fatal error during decoding - %s\n", err)
+			break
+		}
+
+		// Decode() method doesn't treat EAGAIN and EOF as errors
+		// it returns empty frames slice instead. Countinue until
+		// input EOF or frames received.
+		if len(frames) == 0 && drain < 0 {
+			continue
+		}
+
+		if frames, err = gmf.DefaultRescaler(swsctx, frames); err != nil {
+			panic(err)
+		}
+
+		packets, err := cc.Encode(frames, drain)
+		if len(packets) == 0 {
+			continue
+		}
+
+		if err != nil {
+			continue
+		}
+
+		picdata := packets[0].Data()
+		pic = &picdata
+
+		// cleanup here
+		for _, p := range packets {
+			p.Free()
+		}
+
+		for i, _ := range frames {
+			frames[i].Free()
+			frameCount++
+		}
+
+		if pkt != nil {
+			pkt.Free()
+			pkt = nil
+		}
+
+		// we only want to encode first picture then exit
+		break
+	}
+
+	for i := 0; i < inputCtx.StreamsCnt(); i++ {
+		st, _ := inputCtx.GetStream(i)
+		st.CodecCtx().Free()
+		st.Free()
+	}
+	return
+}

apiGo/videoparser/thumbnail/Thumbnailparser_syscall.go

@@ -0,0 +1,130 @@
+// +build !sharedffmpeg
+
+package thumbnail
+
+import (
+	"encoding/json"
+	"fmt"
+	"os/exec"
+	"strconv"
+)
+
+type ExtDependencySupport struct {
+	FFMpeg    bool
+	MediaInfo bool
+}
+
+func Parse(filename string, time uint64) (*string, *VidInfo, error) {
+	// check if the extern dependencies are available
+	mExtDepsAvailable := checkExtDependencySupport()
+	fmt.Printf("FFMPEG support: %t\n", mExtDepsAvailable.FFMpeg)
+	fmt.Printf("MediaInfo support: %t\n", mExtDepsAvailable.MediaInfo)
+
+	var pic *string = nil
+	var info *VidInfo = nil
+
+	if mExtDepsAvailable.FFMpeg {
+		p, err := parseFFmpegPic(filename, time)
+		if err != nil {
+			return nil, nil, err
+		}
+		pic = EncodeBase64(p, "image/jpeg")
+	}
+
+	if mExtDepsAvailable.MediaInfo {
+		i, err := getVideoAttributes(filename)
+		if err != nil {
+			return nil, nil, err
+		}
+		info = i
+	}
+	return pic, info, nil
+}
+
+// check if a specific system command is available
+func commandExists(cmd string) bool {
+	_, err := exec.LookPath(cmd)
+	return err == nil
+}
+
+// ext dependency support check
+func checkExtDependencySupport() *ExtDependencySupport {
+	var extDepsAvailable ExtDependencySupport
+
+	extDepsAvailable.FFMpeg = commandExists("ffmpeg")
+	extDepsAvailable.MediaInfo = commandExists("mediainfo")
+
+	return &extDepsAvailable
+}
+
+func secToString(time uint64) string {
+	return fmt.Sprintf("%02d:%02d:%02d", time/3600, (time/60)%60, time%60)
+}
+
+// parse the thumbail picture from video file
+func parseFFmpegPic(path string, time uint64) (*[]byte, error) {
+	app := "ffmpeg"
+
+	cmd := exec.Command(app,
+		"-hide_banner",
+		"-loglevel", "panic",
+		"-ss", secToString(time),
+		"-i", path,
+		"-vframes", "1",
+		"-q:v", "2",
+		"-f", "singlejpeg",
+		"pipe:1")
+
+	stdout, err := cmd.Output()
+
+	if err != nil {
+		fmt.Println(err.Error())
+		fmt.Println(string(err.(*exec.ExitError).Stderr))
+		return nil, err
+	}
+
+	return &stdout, nil
+}
+
+func getVideoAttributes(path string) (*VidInfo, error) {
+	app := "mediainfo"
+
+	arg0 := path
+	arg1 := "--Output=JSON"
+
+	cmd := exec.Command(app, arg1, "-f", arg0)
+	stdout, err := cmd.Output()
+
+	var t struct {
+		Media struct {
+			Track []struct {
+				Duration string
+				FileSize string
+				Width    string
+				Height   string
+			}
+		}
+	}
+	err = json.Unmarshal(stdout, &t)
+	if err != nil {
+		return nil, err
+	}
+
+	duration, err := strconv.ParseFloat(t.Media.Track[0].Duration, 32)
+	filesize, err := strconv.Atoi(t.Media.Track[0].FileSize)
+	width, err := strconv.Atoi(t.Media.Track[1].Width)
+	height, err := strconv.Atoi(t.Media.Track[1].Height)
+	if err != nil {
+		return nil, err
+	}
+
+	ret := VidInfo{
+		Length:    uint64(duration),
+		Size:      int64(filesize),
+		Width:     uint32(width),
+		Height:    uint32(height),
+		FrameRate: 0,
+	}
+
+	return &ret, nil
+}