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The pirate bay depuis la Belgique
1er avril 2013, par
Mis à jour : Avril 2013
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Publier sur MédiaSpip
13 juin 2013Puis-je poster des contenus à partir d’une tablette Ipad ?
Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir -
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Video files are encoded in MP4, Ogv and WebM (supported by HTML5) and MP4 (supported by Flash).
Audio files are encoded in MP3 and Ogg (supported by HTML5) and MP3 (supported by Flash).
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Sur d’autres sites (6405)
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Artifacts in ffmpeg fifo, low fps, stream ends
11 août 2020, par Ben GardnerI'm using a Raspberry Pi 3B and 4 for this, neither works.


I'm trying to both pass my capture card's input (
/dev/video0
) through a fifo file so I can play it on the screen via omxplayer (1080p/30fps), and also grab frames of/dev/video0
out to a series of jpgs (1920x1080 right now, but I'd like it to be 640x480) so I can do analysis on it while it's being played. The input to the capture card is television via HDMI.

This is the command I use to make the stream go to the fifo and jpgs.


ffmpeg -y -f v4l2 -input_format mjpeg -framerate 30 -video_size 1920x1080 \
-thread_queue_size 16384 -i /dev/video0 -f alsa -ac 1 \
-thread_queue_size 16384 -i hw:CARD=U0x534d0x2109,DEV=0 \
-c:v copy -b:v 32000k -preset faster -x264opts keyint=50 \
-g 25 -pix_fmt yuvj422p -c:a aac -b:a 128k -codec:v copy -f tee \
-map 0:v -map 1:a "fifo.mkv|output_%3d.jpg"



Here is my output, which gives me 30fps originally, sometimes dipping into 29-28 fps, and then skipping (both audio and video) and artifacts in the video after around 5-10 minutes with the severity eventually increasing until it stops :


[mjpeg @ 0x1504490] EOI missing, emulating
Input #0, video4linux2,v4l2, from '/dev/video0':
 Duration: N/A, start: 27151.039849, bitrate: N/A
 Stream #0:0: Video: mjpeg, yuvj422p(pc, bt470bg/unknown/unknown), 1920x1080, 30 fps, 30 tbr, 1000k tbn, 1000k tbc
Guessed Channel Layout for Input Stream #1.0 : mono
Input #1, alsa, from 'hw:CARD=U0x534d0x2109,DEV=0':
 Duration: N/A, start: 1596773777.825328, bitrate: 1536 kb/s
 Stream #1:0: Audio: pcm_s16le, 96000 Hz, mono, s16, 1536 kb/s
Stream mapping:
 Stream #0:0 -> #0:0 (copy)
 Stream #1:0 -> #0:1 (pcm_s16le (native) -> aac (native))
Press [q] to stop, [?] for help
Output #0, tee, to 'fifo.mkv|output_%3d.jpg':
 Metadata:
 encoder : Lavf58.20.100
 Stream #0:0: Video: mjpeg, yuvj422p(pc, bt470bg/unknown/unknown), 1920x1080, q=2-31, 32000 kb/s, 30 fps, 30 tbr, 1000k tbn, 1000k tbc
 Stream #0:1: Audio: aac (LC), 96000 Hz, mono, fltp, 128 kb/s
 Metadata:
 encoder : Lavc58.35.100 aac
[alsa @ 0x1507300] Thread message queue blocking; consider raising the thread_queue_size option (current value: 16384)
[alsa @ 0x1507300] ALSA buffer xrun.time=00:13:55.89 bitrate=N/A speed=0.972x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:14:16.02 bitrate=N/A speed=0.974x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:14:27.25 bitrate=N/A speed=0.972x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:14:33.35 bitrate=N/A speed=0.97x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:14:44.71 bitrate=N/A speed=0.969x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:14:49.71 bitrate=N/A speed=0.97x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:15:01.51 bitrate=N/A speed=0.967x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:15:07.78 bitrate=N/A speed=0.969x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:15:14.27 bitrate=N/A speed=0.962x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:15:26.44 bitrate=N/A speed=0.96x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:15:32.40 bitrate=N/A speed=0.96x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:15:38.63 bitrate=N/A speed=0.963x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:15:45.60 bitrate=N/A speed=0.959x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:15:50.93 bitrate=N/A speed=0.957x
 Last message repeated 1 times
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:00.79 bitrate=N/A speed=0.951x
 Last message repeated 1 times
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:05.29 bitrate=N/A speed=0.949x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:07.19 bitrate=N/A speed=0.949x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:11.72 bitrate=N/A speed=0.945x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:16.02 bitrate=N/A speed=0.944x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:26.39 bitrate=N/A speed=0.953x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:30.22 bitrate=N/A speed=0.938x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:30.98 bitrate=N/A speed=0.937x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:37.66 bitrate=N/A speed=0.941x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:41.28 bitrate=N/A speed=0.935x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:42.95 bitrate=N/A speed=0.934x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:45.82 bitrate=N/A speed=0.933x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:46.76 bitrate=N/A speed=0.932x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:47.05 bitrate=N/A speed=0.931x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:50.74 bitrate=N/A speed=0.927x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:57.05 bitrate=N/A speed=0.927x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:16:58.91 bitrate=N/A speed=0.927x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:17:09.41 bitrate=N/A speed=0.92x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:17:12.04 bitrate=N/A speed=0.917x
[alsa @ 0x1507300] ALSA buffer xrun.time=00:17:12.61 bitrate=N/A speed=0.916x
Killed31579 fps= 28 q=-1.0 size=N/A time=00:17:32.56 bitrate=N/A speed=0.919x



I also occasionally get this error :


[tee @ 0x17001c0] Non-monotonous DTS in output stream 0:1; previous: 99251754, current: 99247503; changing to 99251755. This may result in incorrect timestamps in the output file.



I'm assuming this has something to do with the audio getting routed to the jpg. I've tried
[select=\'v\']
in front of the jpg, which doesn't change the behavior as well as[map=\'1\:a\']
in front of the mkv, which says[matroska @ 0xe446f0] Unknown option 'map'
.

I should also disclaim that I don't have much of an idea of what this command is doing compression-wise, I basically just copy/pasted that part.


What edits do I need to make to get this into a fifo and series of jpgs at the same time ?


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How to set profile compatibility and level indication of an fMP4 using ffmpeg ?
27 novembre 2014, par Pablo MontillaI’m using ffmpeg to generate a fragmented mp4 stream that will be consumed by an HTML5 player using MSE. I think I have a correctly formatted mp4 stream of data with an empty moov at the start and a series of moof+mdat for the video fragments. What I’m stuck is with the codec that’s being received by Chrome.
chrome ://media-internals has this to say :
00:00:00 00 pipeline_state kCreated
00:00:00 00 EVENT PIPELINE_CREATED
00:00:00 00 EVENT WEBMEDIAPLAYER_CREATED
00:00:00 00 url blob:http%3A//localhost/3388b7f1-5567-4d76-a585-0b247affd16a
00:00:00 00 pipeline_state kInitDemuxer
00:00:07 68 error Video codec: avc1.4d401eFrom which I gather the problem is with the encoded data, which should be in
avc1.4d0020
as its specified in the javascript.I’ve seen the answer to html5 video tag codecs attribute, which tells me I need to reset
profile_compatibility
andAVCLevelIndication
, but I couldn’t find an option to do that.Here’s the command line I’m using (the pipe is read and sent to the web page using web sockets) :
ffmpeg -re -i Input.mp4 -map 0:0 -y -c:v libx264 -preset veryslow -x264opts intra-refresh=1 -tune psnr -refs 1 -b:v 1500k -bf 0 -g 8 -b-pyramid none -f mp4 -movflags empty_moov+omit_tfhd_offset+frag_keyframe -frag_duration 1000000 -profile:v main -iods_video_profile 0 -flags +loop \\.\pipe\FeedPipe
So the question is, can I set the
profile_compatiblity
andAVCLevelIndictation
in the ffmpeg command line ? -
Using FFMPEG/RaspiVid streams in C++ program
24 octobre 2020, par NaveenI need to capture the video coming from CSI/Webcam on my Rpi either using FFMPEG or Raspivid. I can do this in commandline using this command.


ffmpeg -i /dev/video0 -f avi - | ./videocapture



I have written a C++ program which uses read() and write() systemcalls. read() to read the STDIN(O/P from ffmpeg). This is copied to a series of buffers(each 65K). . Then another threads reads the buffer and writes the buffer content to a file. So basically I want to create a video file at the end. But when I play the video file it does not work because of file formatting. This is my thread code which writes to the file. Does this look good ? Could you please suggest what I might be doing wrong ? I am sure that the output of ffmpeg is correct.


void WriteToFile(buff_t *buff, char *filename){
// std::cout<<"Starting the thread!!"</ std::cout<<"Couldn't open file, Exiting !!!!!"</ std::cout<<"Buffer Empty!!"</ std::cout<<"Writing To File!!!"<code>