Add media duration to lpms_get_codec_info for GetCodecInfo

ffmpeg/extras.c

@@ -130,6 +130,31 @@ int lpms_rtmp2hls(char *listen, char *outf, char *ts_tmpl, char* seg_time, char
   return ret == AVERROR_EOF ? 0 : ret;
 }
 
+//Calculates the duration of audio stream by counting the number of audio packets
+double calculate_audio_dur(AVFormatContext *ic, int astream) {
+  AVPacket pkt;
+  av_init_packet(&pkt);
+  double duration = 0;
+  int64_t last_pts = AV_NOPTS_VALUE;
+  // Seek to the beginning of the audio stream
+  av_seek_frame(ic, astream, 0, AVSEEK_FLAG_BACKWARD);
+  while (av_read_frame(ic, &pkt) >= 0) {
+    if (pkt.stream_index == astream) {
+      if (pkt.pts != AV_NOPTS_VALUE) {
+        if (last_pts != AV_NOPTS_VALUE) {
+          // Calculate the difference between the current and last PTS
+          int64_t pts_diff = pkt.pts - last_pts;
+          // Convert the PTS difference to seconds and add to duration
+          duration += pts_diff * av_q2d(ic->streams[astream]->time_base);
+        }
+        last_pts = pkt.pts;
+      }
+      av_packet_unref(&pkt);
+    }
+  }
+  return duration;
+}
+
 #define GET_CODEC_INTERNAL_ERROR -1
 #define GET_CODEC_OK 0
 #define GET_CODEC_NEEDS_BYPASS 1
@@ -163,6 +188,13 @@ int lpms_get_codec_info(char *fname, pcodec_info out)
   if(!audio_present && !video_present) {
     // instead of returning -1
     ret = GET_CODEC_STREAMS_MISSING;
+  } else if (video_present) {
+    out->dur = ic->duration / AV_TIME_BASE;
+  }
+
+  if (out->dur <= 0) {
+    //ic->duration / AV_TIME_BASE doesn't return accurate duration for audio-only streams, so we calculate the duration manually
+    out->dur = calculate_audio_dur(ic, astream);
   }
   // Return
   if (video_present && vc->name) {
@@ -176,6 +208,7 @@ int lpms_get_codec_info(char *fname, pcodec_info out)
       }
       out->width  = ic->streams[vstream]->codecpar->width;
       out->height = ic->streams[vstream]->codecpar->height;
+      out->fps = av_q2d(ic->streams[vstream]->avg_frame_rate);
   } else {
       // Indicate failure to extract video codec from given container
       out->video_codec[0] = 0;

ffmpeg/extras.h

@@ -7,6 +7,8 @@ typedef struct s_codec_info {
   int    pixel_format;
   int    width;
   int    height;
+  double fps;
+  double dur;
 } codec_info, *pcodec_info;
 
 int lpms_rtmp2hls(char *listen, char *outf, char *ts_tmpl, char *seg_time, char *seg_start);

ffmpeg/ffmpeg.go

@@ -245,6 +245,8 @@ type MediaFormatInfo struct {
 	Acodec, Vcodec string
 	PixFormat      PixelFormat
 	Width, Height  int
+	FPS            float32
+	Dur            float32
 }
 
 func (f *MediaFormatInfo) ScaledHeight(width int) int {
@@ -277,6 +279,9 @@ func GetCodecInfo(fname string) (CodecStatus, MediaFormatInfo, error) {
 	format.PixFormat = PixelFormat{int(params_c.pixel_format)}
 	format.Width = int(params_c.width)
 	format.Height = int(params_c.height)
+	format.FPS = float32(params_c.fps)
+	format.Dur = float32(params_c.dur)
+
 	return status, format, nil
 }
 

ffmpeg/ffmpeg_test.go

@@ -1869,3 +1869,65 @@ func TestResolution_Clamp(t *testing.T) {
 	checkError = require.Error
 	test(l, Size{300, 600}, portrait, Size{300, 600})
 }
+
+func TestDuration_GetCodecInfo(t *testing.T) {
+	wd, err := os.Getwd()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	files := []string{"bunny.mp4", "duplicate-audio-dts.ts", "bunny.mp3", "bunny.webm", "bunny.flac", "bunny.m4a"}
+	for _, file := range files {
+		start := time.Now()
+		fname := path.Join(wd, "..", "data", file)
+		_, format, err := GetCodecInfo(fname)
+		data, err := ioutil.ReadFile(fname)
+		if err != nil {
+			t.Error(err)
+		}
+
+		_, format, err = GetCodecInfoBytes(data)
+		if err != nil {
+			t.Error(err)
+		}
+
+		took := time.Since(start).Milliseconds()
+		fmt.Printf("%v\ttook=%v\tdur=%v\tacodec=%v\n", fname, took, format.Dur, format.Acodec)
+		if format.Dur <= float32(0) {
+			assert.Fail(t, "Duration should be > 0", format.Dur)
+		} else {
+			assert.True(t, format.Dur > float32(0), "Duration should be > 0", format.Dur)
+		}
+	}
+}
+
+func TestFPS_GetCodecInfo(t *testing.T) {
+	wd, err := os.Getwd()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	files := []string{"bunny.mp4", "duplicate-audio-dts.ts", "bunny.webm"}
+	for _, file := range files {
+		start := time.Now()
+		fname := path.Join(wd, "..", "data", file)
+		_, format, err := GetCodecInfo(fname)
+		data, err := ioutil.ReadFile(fname)
+		if err != nil {
+			t.Error(err)
+		}
+
+		_, format, err = GetCodecInfoBytes(data)
+		if err != nil {
+			t.Error(err)
+		}
+
+		took := time.Since(start).Milliseconds()
+		fmt.Printf("%v\ttook=%v\tfps=%v\tdur=%v\tacodec=%v\n", fname, took, format.FPS, format.Dur, format.Acodec)
+		if format.FPS <= float32(0) {
+			assert.Fail(t, "FPS should be > 0", format.FPS)
+		} else {
+			assert.True(t, format.FPS > float32(0), "FPS should be > 0", format.FPS)
+		}
+	}
+}