[FFmpeg-user] Video and Audio is off-sync on Decklink SDI output

Tung Tran tung.tran at v247.com
Thu Mar 2 18:24:27 EET 2017


Dear Carl

Sorry for late response as I dont know why somehow google email filtered
your previous emails.

The reason I used vf setpts filter is, if not, the image on SDI outout will
lag alot.
I played around and found out if I use vf setpts then I can fix lagging
issue but its lipsync.

Here is the log

*Before apply vf filter*

[flv @ 0x38d33c0] audio stream discovered after head already parsed
[flv @ 0x38d33c0] video stream discovered after head already parsed
[h264 @ 0x38f4660] Increasing reorder buffer to 2
Input #0, flv, from 'rtmp://something':
  Duration: N/A, start: 26639.381000, bitrate: N/A
    Stream #0:0: Audio: aac (LC), 48000 Hz, stereo, fltp
    Stream #0:1: Video: h264 (High), yuv420p(tv, bt709, progressive),
1920x1080 [SAR 1:1 DAR 16:9], 30.30 fps, 29.97 tbr, 1k tbn, 59.94 tbc
[decklink @ 0x38f5a00] Found Decklink mode 1920 x 1080 with rate 29.97
Output #0, decklink, to 'DeckLink SDI (1)':
  Metadata:
    encoder         : Lavf57.66.102
    Stream #0:0: Video: rawvideo (UYVY / 0x59565955), uyvy422, 1920x1080
[SAR 1:1 DAR 16:9], q=2-31, 200 kb/s, 29.97 fps, 29.97 tbn, 29.97 tbc
    Metadata:
      encoder         : Lavc57.80.101 rawvideo
    Stream #0:1: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
    Metadata:
      encoder         : Lavc57.80.101 pcm_s16le
Stream mapping:
  Stream #0:1 -> #0:0 (h264 (native) -> rawvideo (native))
  Stream #0:0 -> #0:1 (aac (native) -> pcm_s16le (native))
Press [q] to stop, [?] for help
[decklink @ 0x38f5a00] Timestamps are unset in a packet for stream 0. This
is deprecated and will stop working in the future. Fix your code to set the
timestamps properly
[decklink @ 0x38f5a00] Encoder did not produce proper pts, making some up.
frame=  156 fps= 38 q=-0.0 size=N/A time=00:00:05.20 bitrate=N/A dup=35
drop=0 speed=1.33x
frame=  291 fps= 36 q=-0.0 size=N/A time=00:00:09.70 bitrate=N/A dup=35
drop=0 speed=1.19x
frame=  414 fps= 34 q=-0.0 size=N/A time=00:00:13.81 bitrate=N/A dup=35
drop=0 speed= 1.1x

*After apply vf setpts filter*


     encoder         : Lavc57.80.101 pcm_s16le
Stream mapping:
  Stream #0:1 -> #0:0 (h264 (native) -> rawvideo (native))
  Stream #0:0 -> #0:1 (aac (native) -> pcm_s16le (native))
Press [q] to stop, [?] for help
[decklink @ 0x42bd1e0] Timestamps are unset in a packet for stream 0. This
is deprecated and will stop working in the future. Fix your code to set the
timestamps properly
[decklink @ 0x42bd1e0] Encoder did not produce proper pts, making some up.
[decklink @ 0x42bd1e0] There's no buffered audio. Audio will misbehave!2
drop=0 speed=3.41x
[decklink @ 0x42bd1e0] There's no buffered audio. Audio will misbehave!2
drop=0 speed=2.97x
[decklink @ 0x42bd1e0] There's no buffered audio. Audio will misbehave!2
drop=0 speed=2.67x
[decklink @ 0x42bd1e0] There's no buffered audio. Audio will misbehave!2
drop=0 speed=2.44x
[decklink @ 0x42bd1e0] There's no buffered audio. Audio will misbehave!2
drop=0 speed=2.27x
[decklink @ 0x42bd1e0] There's no buffered audio. Audio will misbehave!2
drop=0 speed=1.68x
    Last message repeated 1 times
[decklink @ 0x42bd1e0] There's no buffered audio. Audio will misbehave!2
drop=0 speed=1.66x
[decklink @ 0x42bd1e0] There's no buffered audio. Audio will misbehave!2
drop=0 speed=1.64x
[decklink @ 0x42bd1e0] There's no buffered audio. Audio will misbehave!2
drop=0 speed=1.62x
[decklink @ 0x42bd1e0] There's no buffered audio. Audio will misbehave!2
drop=0 speed= 1.6x
[decklink @ 0x42bd1e0] There's no buffered audio. Audio will misbehave!2
drop=0 speed=1.58x
[decklink @ 0x42bd1e0] There's no buffered audio. Audio will misbehave!2
drop=0 speed=1.57x
    Last message repeated 1 times
[decklink @ 0x42bd1e0] There's no buffered audio. Audio will misbehave!2
drop=0 speed=1.55x
[decklink @ 0x42bd1e0] There's no buffered audio. Audio will misbehave!2
drop=0 speed=1.54x
    Last message repeated 2 times
[decklink @ 0x42bd1e0] There's no buffered audio. Audio will misbehave!2
drop=0 speed=1.43x
    Last message repeated 1 times
[decklink @ 0x42bd1e0] There's no buffered audio. Audio will misbehave!2
drop=0 speed=1.42x


---
Best regards,

*Tung Tran*




On Wed, Mar 1, 2017 at 2:53 AM, Carl Eugen Hoyos <ceffmpeg at gmail.com> wrote:

> 2017-02-28 23:32 GMT+01:00 Matthias, Thomas <Thomas.Matthias at dolby.com>:
> > If filters is the wrong solution for setting points for Decklink SDI
> > output, what would be the correct way to do so?
>
> What are "points" / what happens if you don't use the setpts filters?
>
> Please do not top-post here, Carl Eugen
> _______________________________________________
> ffmpeg-user mailing list
> ffmpeg-user at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>
> To unsubscribe, visit link above, or email
> ffmpeg-user-request at ffmpeg.org with subject "unsubscribe".
>


More information about the ffmpeg-user mailing list