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Autres articles (79)
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Organiser par catégorie
17 mai 2013, parDans MédiaSPIP, une rubrique a 2 noms : catégorie et rubrique.
Les différents documents stockés dans MédiaSPIP peuvent être rangés dans différentes catégories. On peut créer une catégorie en cliquant sur "publier une catégorie" dans le menu publier en haut à droite ( après authentification ). Une catégorie peut être rangée dans une autre catégorie aussi ce qui fait qu’on peut construire une arborescence de catégories.
Lors de la publication prochaine d’un document, la nouvelle catégorie créée sera proposée (...) -
Récupération d’informations sur le site maître à l’installation d’une instance
26 novembre 2010, parUtilité
Sur le site principal, une instance de mutualisation est définie par plusieurs choses : Les données dans la table spip_mutus ; Son logo ; Son auteur principal (id_admin dans la table spip_mutus correspondant à un id_auteur de la table spip_auteurs)qui sera le seul à pouvoir créer définitivement l’instance de mutualisation ;
Il peut donc être tout à fait judicieux de vouloir récupérer certaines de ces informations afin de compléter l’installation d’une instance pour, par exemple : récupérer le (...) -
Emballe Médias : Mettre en ligne simplement des documents
29 octobre 2010, parLe plugin emballe médias a été développé principalement pour la distribution mediaSPIP mais est également utilisé dans d’autres projets proches comme géodiversité par exemple. Plugins nécessaires et compatibles
Pour fonctionner ce plugin nécessite que d’autres plugins soient installés : CFG Saisies SPIP Bonux Diogène swfupload jqueryui
D’autres plugins peuvent être utilisés en complément afin d’améliorer ses capacités : Ancres douces Légendes photo_infos spipmotion (...)
Sur d’autres sites (7271)
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How to concatenate two MP4 files, which require http basic Authorization : Bearer , using ffmpeg ?
8 juillet 2023, par Jeff StrongmanHello dear ffmpeg experts ! 🧠 🎯


I ran the following command, which worked perfectly :


ffmpeg -protocol_whitelist https,concat,tls,tcp -i "concat :https://dash.akamaized.net/akamai/bbb_30fps/bbb_30fps_1280x720_4000k/bbb_30fps_1280x720_4000k_0.m4v|https://dash.akamaized.net/akamai/bbb_30fps/bbb_30fps_1280x720_4000k/bbb_30fps_1280x720_4000k_1.m4v|https://dash.akamaized.net/akamai/bbb_30fps/bbb_30fps_1280x720_4000k/bbb_30fps_1280x720_4000k_2.m4v" -c:v copy -vframes 180 -y Movie_of_6_seconds.mp4


I followed the recommended solution of the following post :
How to concatenate two MP4 files using FFmpeg ?


You can execute the command on your local computer and see that it should run just fine...


I used 3. concat protocol, which does indeed concat init + progressive segments


However... when every segment on a server I refer to, is password protected, it fails with 401 Unauthorized, even though I added the following line :
-headers "Authorization : Bearer bas64user:password" , before specifying the -i "concat :...".


It seems to me... that the headers don't pass to the concat command inside of the input of ffmpeg... and it simply ignores them. When I used the same -headers command, on a single file, without concat, it passed the authorization successfully


Notes :


- 

- Even though every segment has a length of 120 frames (So in maximum, I could have generated 2*120 = 240 frames... I wanted a movie of 6 seconds and not 8... And by this way, to test that ffmpeg is smart enough to stop processing the whole input). To do that, I used -vframes 180, where 180 / 30 (FPS) = 6 seconds
- I used -c:v copy, to get without re-encoding, only the video part (No audio !)
- I used -y to override existing file...
- 0.m4v, is the init file ! it is a small file, that has metadata of the original video which was produced with mpeg-dash
- 1.m4v and 2.m4v, are the progressive segments












Is there a way, to pass the http basic headers (Authorization : Bearer) to all of the chained files ?


Like :


- 

- Via a json content type on the ffmpeg request
- Or user:password@video_segment (Although... it seems to me it's not a header ?)
- Somehow specify header inside the concat command ?








I don't want to first download all files and then get rid of the password protected... as it both takes ridiculous time & other resources... and I would like to record from a segment that is "endless", meaning a camera that keeps streaming data.


Thanks in advance 🙏🏻,


FFmpeg noobie 🙈


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Is there an efficient way to retrieve frames from a video in Android ?
28 mars 2015, par NaveedI have an app which requires me to retrieve frames from a video and do some processing with them. However it seems like that the frame retrieval is very slow to the point where it is unacceptable. Sometimes it is taking upto 2.5 second to retrieve a single frame. I am using the MediaMetadataRetriever as most stackoverflow questions suggested. However the performance is very bad. Here is what I have :
private List<bitmap> retrieveFrames() {
MediaMetadataRetriever fmmr = new MediaMetadataRetriever();
fmmr.setDataSource("/path/to/some/video.mp4");
String strLength = fmmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_DURATION);
long milliSecs = Long.parseLong(strLength);
long microSecLength = milliSecs * 1000;
Log.d("TAG", "length: " + microSecLength);
long one_sec = 1000000; // one sec in micro seconds
ArrayList<bitmap> frames = new ArrayList<>();
int j = 0;
for (int i = 0; i < microSecLength; i += (one_sec / 5)) {
long time = System.currentTimeMillis();
Bitmap frame = fmmr.getFrameAtTime(i, MediaMetadataRetriever.OPTION_CLOSEST);
j++;
Log.d("TAG", "Frame number: " + j + " Time taken: " + (System.currentTimeMillis() - time));
// commented out because each frame would be written to disk instead of holding them in memory
// frames.add(frame);
}
fmmr.release();
return frames;
}
</bitmap></bitmap>The above will logs :
03-26 21:49:29.781 13213-13239/com.example.naveed.myapplication D/TAG﹕ length: 4949000
03-26 21:49:30.187 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 1 Time taken: 406
03-26 21:49:30.779 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 2 Time taken: 592
03-26 21:49:31.578 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 3 Time taken: 799
03-26 21:49:32.632 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 4 Time taken: 1054
03-26 21:49:33.895 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 5 Time taken: 1262
03-26 21:49:35.382 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 6 Time taken: 1486
03-26 21:49:37.128 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 7 Time taken: 1746
03-26 21:49:39.077 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 8 Time taken: 1948
03-26 21:49:41.287 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 9 Time taken: 2210
03-26 21:49:43.717 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 10 Time taken: 2429
03-26 21:49:44.093 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 11 Time taken: 376
03-26 21:49:44.707 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 12 Time taken: 614
03-26 21:49:45.539 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 13 Time taken: 831
03-26 21:49:46.597 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 14 Time taken: 1057
03-26 21:49:47.875 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 15 Time taken: 1278
03-26 21:49:49.384 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 16 Time taken: 1508
03-26 21:49:51.112 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 17 Time taken: 1728
03-26 21:49:53.096 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 18 Time taken: 1983
03-26 21:49:55.315 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 19 Time taken: 2218
03-26 21:49:57.711 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 20 Time taken: 2396
03-26 21:49:58.065 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 21 Time taken: 354
03-26 21:49:58.640 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 22 Time taken: 574
03-26 21:49:59.369 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 23 Time taken: 728
03-26 21:50:00.112 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 24 Time taken: 742
03-26 21:50:00.834 13213-13239/com.example.naveed.myapplication D/TAG﹕ Frame number: 25 Time taken: 721As you can see from above, it is taking about 18 - 25 sec to retrieve 25 frames from a 4 sec long video.
I have also tried this which uses FFmpeg underneath to do the same. I am not sure how well this library is implemented but it only improves the over all performance by a couple of seconds meaning it takes about 15-20 sec to do the same.
So my question is : is there a way to do it quicker ? My friend has an iOS app where he does something similar but it only takes couple of seconds and he is grabbing even more frames however he is not sure how to do it on android.
Is there anything on android that would speed up the process. Am I approaching this wrong ?
The end goal is to stitch those frames together into a gif.
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Split h.264 stream into multiple parts in python
31 janvier 2023, par BillPlayzMy objective is to split an h.264 stream into multiple parts, meaning while reading the stream from a pipe i would like to save it into x second long packages (in my case 10).


I am using a libcamera-vid subprocess on my Raspberry Pi that outputs the h.264 stream into stdout.

Might be irrelevant, depends : libcamera-vid outputs a message every frame and I am able to locate it at isFrameStopLine
To convert the stream, I use an ffmpeg subprocess, as you can see in the code below.

Imagine it like that :

Stream is running...

- Start recording to a file

- Sleep x seconds

- Finish recording to file

- Start recording a new file

- Sleep x seconds

- Finish recording the new file

- and so on...

Here is my current code, however upon running the first export succeeds, and after the second or third the ffmpeg-subprocess is terminating with the error :

pipe:: Invalid data found when processing input

And shortly after, the python process, because of the ffmpeg termination i believe.
Traceback (most recent call last): File "/home/survpi-camera/main.py", line 56, in <module> processStreamLine(readData) File "/home/survpi-camera/main.py", line 16, in processStreamLine streamInfo["process"].stdin.write(data) BrokenPipeError: [Errno 32] Broken pipe</module>


recentStreamProcesses = []
streamInfo = {
 "lastStreamStart": -1,
 "process": None
}

def processStreamLine(data):
 isInfoLine = ((data.startswith(b"[") and (b"INFO" in data)) or (data == b"Preview window unavailable"))
 isFrameStopLine = (data.startswith(b"#") and (b" fps) exp" in data))
 if ((not isInfoLine) and (not isFrameStopLine)):
 streamInfo["process"].stdin.write(data)
 
 if (isFrameStopLine):
 if (time.time() - streamInfo["lastStreamStart"] >= 10):
 print("10 seconds passed, exporting...")
 exportStream()
 createNewStream()

def createNewStream():
 streamInfo["lastStreamStart"] = time.time()
 streamInfo["process"] = subprocess.Popen([
 "ffmpeg",
 "-r","30",
 "-i","-",
 "-c","copy",("/home/survpi-camera/" + str(round(time.time())) + ".mp4")
 ],stdin=subprocess.PIPE,stderr=subprocess.STDOUT)
 print("Created new streamProcess.")

def exportStream():
 print("Exporting...")
 streamInfo["process"].stdin.close()
 recentStreamProcesses.append(streamInfo["process"])


cameraProcess = subprocess.Popen([
 "libcamera-vid",
 "-t","0",
 "--width","1920",
 "--height","1080",
 "--codec","h264",
 "--inline",
 "--listen",
 "-o","-"
],stdout=subprocess.PIPE,stdin=subprocess.PIPE,stderr=subprocess.STDOUT)

createNewStream()

while True:
 readData = cameraProcess.stdout.readline()
 
 processStreamLine(readData)



Thank you in advance !