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Questions tagged [pts]

The presentation timestamp (PTS) is a timestamp metadata field in a video stream.

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how to remove PTS gap within a file when transcoding with ffmpeg?

i have a video which is from rtmp streaming. Since the broadcasting is on and off frequently, the archived file has PTS like below (assume that this is sec) 0--10--20--30--40 120--130--140 there's discontinuity between 40 and 120 sec. duration of…
jsBaek
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ffmpeg muxing to mkv container

I'm muxing H264 frames with alaw audio frames coming from the RTP stream but I'm having some problems with setting fps for the mkv container. For the AVPacket::pts I am using the calculated presentation time (from RTCP SR reports) I am rescaling…
Pawel K
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Linux redirect input via proc fd0, dev/pts

In Ubuntu 13.04 Using VMware, I have two terminals(PID 1000 - /dev/pts0, PID 2000 - /dev/pts2) If I do this from terminal 2(/dev/pts2) ... echo 'ls -al' > /proc/1000/fd/0 I can see that 'ls -al' prompts up in terminal 0(/dev/pts0) however, this is…
daehee
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Is packet duration guaranteed to be uniform for entire stream?

I use packet duration to translate from frame index to pts and back, and I'd like to be sure that this is a reliable method of doing so. Alternatively, is there a better way to translate pts to a frame index and vice versa? A snippet showing my…
karl_
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How to synchronize audio and video using ffmpeg libraries?

Stuck writing a very basic media player in C, using SDL and ffmpeg libraries. Initially, followed the theory in this page to get an idea about the entire program and the usage of libraries. After coding from scratch, thanks to that tutorial and many…
progammer
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why there are 23 files in /dev/pts while only 8 pts are showed using who command?

only 8 pts files are used [root@home tmp]# who root pts/2 2012-08-15 18:36 (:pts/1:S.0) root pts/6 2012-08-21 16:36 (10.10.11.168) root pts/3 2012-08-15 19:24 (:pts/1:S.1) root pts/10 2012-08-15 21:04…
hugemeow
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Can't get the right formula to set frame pts for a stream using libav

I'm trying to save a stream of frames as mp4. Source framerate is not fixed and it stay in the range [15,30] Encoder params: ... eCodec.time_base = AVRational(1,3000); eCodec.framerate = AVRational(30, 1); ... Stream params: eStream =…
user1365836
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Use "Clock Time" instead of Running Time for GStreamer Pipeline

I have a two GStreamer pipelines, one is like a "source" pipeline streaming a live camera feed into an external channel, and the second pipeline is like a "sink" pipeline that reads from the other end of that channel and outputs the live video to…
Garrit Strenge
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How to properly concatenate mp4 videos with GStreamer

We are relatively new to GStreamer. We are running GStreamer 1.18.4 on a Linux-based custom board and we have a pipeline receiving video from an IP camera using rtspsrc and creating MP4 video clips of 10 seconds. We faced the missing PTS issue and…
Aldanajaramillo
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Questons about the relation of PTS and DTS in H.264

Why is PTS = DTS when there is no B frame in H264? Why is DTS not always smaller than PTS, because decoding takes time, even if PTS - DTS is a very small number? I think the frame must be decoded before playing or is there something wrong with my…
DJI_lover
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How to set pts, dts and duration in ffmpeg library?

I want to pack some compressed video packets(h.264) to ".mp4" container. One word, Muxing, no decoding and no encoding. And I have no idea how to set pts, dts and duration. I get the packets with "pcap" library. I removed headers before compressed…
hslee
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How can I detect whether the mouse is in a certain part of the screen?

So I'm trying to change the value of a variable based on the Y coordinate of the pointer, and I'm not sure how I would do this. I tried this: var righttext = mousemove.clientY; switch(righttext){ case //not sure what to put here } but…
Jodast
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Why am I unable to scale a 4-second 60 fps clip down to exactly 1 second?

I'm currently using the setpts filter to speed up or slow down different clips and accuracy is very important to me ( context: I'm concatenating these into a final clip that needs to be perfectly in sync with a separate video.) I've been using this…
joeycato
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swift 4 - avfoundation AVAssetWriter incorrect PTS/DTS

I'm changing Aperture code to be able set custom video bitrate. When I recorded video, the quality and framerate is good, but i see problems with metadata. When I run ffmpeg converting, i see the folowing errors: DTS 96841521, next:14266523 st:0…
Matho
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ffmpeg PTS calculation

i im using ffmpeg to save stream in memory and then restream to my html5 web page...i would like to know how can i manually calculate PTS value like xtream panel codes does have (PTS/Network Speed 1.00x or 1.34x or 0.94x)....i can't get output from…
user2631534
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