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Médias (91)
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Head down (wav version)
26 septembre 2011, par
Mis à jour : Avril 2013
Langue : English
Type : Audio
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Echoplex (wav version)
26 septembre 2011, par
Mis à jour : Avril 2013
Langue : English
Type : Audio
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Discipline (wav version)
26 septembre 2011, par
Mis à jour : Avril 2013
Langue : English
Type : Audio
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Letting you (wav version)
26 septembre 2011, par
Mis à jour : Avril 2013
Langue : English
Type : Audio
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1 000 000 (wav version)
26 septembre 2011, par
Mis à jour : Avril 2013
Langue : English
Type : Audio
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999 999 (wav version)
26 septembre 2011, par
Mis à jour : Avril 2013
Langue : English
Type : Audio
Autres articles (61)
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Gestion des droits de création et d’édition des objets
8 février 2011, parPar défaut, beaucoup de fonctionnalités sont limitées aux administrateurs mais restent configurables indépendamment pour modifier leur statut minimal d’utilisation notamment : la rédaction de contenus sur le site modifiables dans la gestion des templates de formulaires ; l’ajout de notes aux articles ; l’ajout de légendes et d’annotations sur les images ;
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Supporting all media types
13 avril 2011, parUnlike most software and media-sharing platforms, MediaSPIP aims to manage as many different media types as possible. The following are just a few examples from an ever-expanding list of supported formats : images : png, gif, jpg, bmp and more audio : MP3, Ogg, Wav and more video : AVI, MP4, OGV, mpg, mov, wmv and more text, code and other data : OpenOffice, Microsoft Office (Word, PowerPoint, Excel), web (html, CSS), LaTeX, Google Earth and (...)
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Dépôt de média et thèmes par FTP
31 mai 2013, parL’outil MédiaSPIP traite aussi les média transférés par la voie FTP. Si vous préférez déposer par cette voie, récupérez les identifiants d’accès vers votre site MédiaSPIP et utilisez votre client FTP favori.
Vous trouverez dès le départ les dossiers suivants dans votre espace FTP : config/ : dossier de configuration du site IMG/ : dossier des média déjà traités et en ligne sur le site local/ : répertoire cache du site web themes/ : les thèmes ou les feuilles de style personnalisées tmp/ : dossier de travail (...)
Sur d’autres sites (8183)
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Transcode HLS Segments individually using FFMPEG
27 mai 2013, par rayhI am recording a continuous, live stream to a high-bitrate HLS stream. I then want to asynchronously transcode this to different formats/bitrates. I have this working, mostly, except audio artefacts are appearing between each segment (gaps and pops).
Here is an example ffmpeg command line :
ffmpeg -threads 1 -nostdin -loglevel verbose \
-nostdin -y -i input.ts -c:a libfdk_aac \
-ac 2 -b:a 64k -y -metadata -vn output.tsInspecting an example sound file shows that there is a gap at the end of the audio :
And the start of the file looks suspiciously attenuated (although this may not be an issue) :
My suspicion is that these artefacts are happening because transcoding are occurring without the context of the stream as a whole.
Any ideas on how to convince FFMPEG to produce audio that will fit back into a HLS stream ?
** UPDATE 1 **
Here are the start/end of the original segment. As you can see, the start still appears the same, but the end is cleanly ended at 30s. I expect some degree of padding with lossy encoding, but I there is some way that HLS manages to do gapless playback (is this related to iTunes method with custom metadata ?)
** UPDATED 2 **
So, I converted both the original (128k aac in MPEG2 TS) and the transcoded (64k aac in aac/adts container) to WAV and put the two side-by-side. This is the result :
I'm not sure if this is representative of how a client will play it back, but it seems a bit odd that decoding the transcoded one introduces a gap at the start and makes the segment longer. Given they are both lossy encoding, I would have expected padding to be equally present in both (if at all).
** UPDATE 3 **
According to http://en.wikipedia.org/wiki/Gapless_playback - Only a handful of encoders support gapless - for MP3, I've switched to lame in ffmpeg, and the problem, so far, appears to have gone.
For AAC (see http://en.wikipedia.org/wiki/FAAC), I have tried libfaac (as opposed to libfdk_aac) and it also seems to produce gapless audio. However, the quality of the latter isn't that great and I'd rather use libfdk_aac is possible.
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Flutter video_compress and then ffmpeg trim video to 30s fails with endless logs
7 mars 2021, par Charles BassI am trying to make a simple app in Flutter. A user can either take or pick a video and then upload it. However, I wanted to compress the video for storage purposes on firebase storage, and also trim it to only get the first 30 seconds.


I am facing a very puzzling problem. I am able to compress the video, but with the resultant file, FFmpeg fails to trim it and I get endless logs which result in me having to stop the app and re-run. Alternatively, I am able to trim the video, but with the resultant file, I am unable to compress it getting the error :
Failed to open file '/data/user/0/live.roots.roots/app_flutter/TRIMMED.mp4'. (No such file or directory) PlatformException(error, java.io.IOException: Failed to instantiate extractor., null, java.lang.RuntimeException: java.io.IOException: Failed to instantiate extractor.

This is my code below :




//! function that controls file compression and trimming
static Future<file> compressFile(File file) async {
 print('[COMPRESSING FILE]');

 String mimeStr = lookupMimeType(file.path);
 var fileType = mimeStr.split('/');

 if (fileType.contains("image")) {
 print('[COMPRESSING FILE] - file is image');
 String tempPath = (await getTemporaryDirectory()).path;
 String targetPath = '$tempPath/${DateTime.now().toIso8601String()}.jpg';
 return await compressImageAndGetFile(file, targetPath);
 } else {
 print('[COMPRESSING FILE] - file is video');

 final compressedVideoFile = await compressVideoAndGetFile(file);
 print('[VIDEO FILE COMPRESSED]');
 return await trimVideoGetFile(compressedVideoFile);
 }
 }
 
 
//! function to compress video
static Future<file> compressVideoAndGetFile(File file) async {
 print('[COMPRESSING VIDEO]');

 var result = await VideoCompress.compressVideo(
 file.absolute.path,
 quality: VideoQuality.DefaultQuality,
 deleteOrigin: true,
 );

 print('[COMPRESSED VIDEO TO]: ${result.file.path}');

 return result.file;
 }
 
//! function to trim video
static Future<file> trimVideoGetFile(File file) async {
 print('[TRIMMING VIDEO]');

 Directory appDocumentDir = await getApplicationDocumentsDirectory();
 String rawDocumentPath = appDocumentDir.path;
 String outputPath = rawDocumentPath + "/TRIMMED.mp4";

 final newFile = File(outputPath);

 if (await newFile.exists()) {
 await newFile.delete();
 }

 _flutterFFmpeg
 .execute(
 "-ss 00:00:00 -i ${file.path} -to 00:00:30 -c copy $outputPath")
 .then((rt) async {
 print('[TRIMMED VIDEO RESULT] : $rt');
 if (rt == -1) {
 throw Exception("Something went wrong when trimming the video");
 }
 });

 return File(outputPath);
 }</file></file></file>






Thank you in advance


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Lego Mindstorms RSO Format
14 juillet 2010, par Multimedia Mike — GeneralI recently read a magazine article about Lego Mindstorms. Naturally, the item that caught my eye was the mention of a bit of Lego software that converts various audio file formats to a custom format called RSO that can be downloaded into a Mindstorms project to make the creation output audio. To read different sources, one might be left with the impression that there is something super-duper top secret proprietary about the format. Such impressions do not hold up under casual analysis of a sample file.
A Google search for "filetype:rso" yielded a few pre-made sample that I have mirrored into the samples archive. The format appears to be an 8-byte header followed by unsigned, 8-bit PCM. More on the wiki. If FFmpeg could gain an RSO file muxer, that would presumably be a heroic feat to the Lego hacking community.
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